When there is an node name conflicts, such messages are displayed within Consul:
`consul.fsm: EnsureRegistration failed: failed inserting node: Error while renaming Node ID: "e1d456bc-f72d-98e5-ebb3-26ae80d785cf": Node name node001 is reserved by node 05f10209-1b9c-b90c-e3e2-059e64556d4a with name node001`
While it is easy to find the node that has reserved the name, it is hard to find
the node trying to aquire the name since it is not registered, because it
is not part of `consul members` output
This PR will display the IP of the offender and solve far more easily those issues.
The embedded `Server` field on a `DNSServer` is only set inside of the
`ListenAndServe` method. If that method fails for reasons like the
address being in use and is not bindable, then the `Server` field will
not be set and the overall `Agent.Start()` will fail.
This will trigger the inner loop of `TestAgent.Start()` to invoke
`ShutdownEndpoints` which will attempt to pretty print the DNS servers
using fields on that inner `Server` field. Because it was never set,
this causes a nil pointer dereference and crashes the test.
Previously `verify_incoming` was required when turning on `auto_encrypt.allow_tls`, but that doesn't work together with HTTPS UI in some scenarios. Adding `verify_incoming_rpc` to the allowed configurations.
AutoEncrypt needs the server-port because it wants to talk via RPC. Information from gossip might not be available at that point and thats why the server-port is being used.
- Bootstrap escape hatches are OK.
- Public listener/cluster escape hatches are OK.
- Upstream listener/cluster escape hatches are not supported.
If an unsupported escape hatch is configured and the discovery chain is
activated log a warning and act like it was not configured.
Fixes#6160
Compiling this will set an optional SNI field on each DiscoveryTarget.
When set this value should be used for TLS connections to the instances
of the target. If not set the default should be used.
Setting ExternalSNI will disable mesh gateway use for that target. It also
disables several service-resolver features that do not make sense for an
external service.
If the entry is updated for reasons other than protocol it is surprising
that the value is explicitly persisted as 'tcp' rather than leaving it
empty and letting it fall back dynamically on the proxy-defaults value.
Since generated envoy clusters all are named using (mostly) SNI syntax
we can have envoy read the various fields out of that structure and emit
it as stats labels to the various telemetry backends.
I changed the delimiter for the 'customization hash' from ':' to '~'
because ':' is always reencoded by envoy as '_' when generating metrics
keys.
Add parameter local-only to operator keyring list requests to force queries to only hit local servers (no WAN traffic).
HTTP API: GET /operator/keyring?local-only=true
CLI: consul keyring -list --local-only
Sending the local-only flag with any non-GET/list request will result in an error.
Failover is pushed entirely down to the data plane by creating envoy
clusters and putting each successive destination in a different load
assignment priority band. For example this shows that normally requests
go to 1.2.3.4:8080 but when that fails they go to 6.7.8.9:8080:
- name: foo
load_assignment:
cluster_name: foo
policy:
overprovisioning_factor: 100000
endpoints:
- priority: 0
lb_endpoints:
- endpoint:
address:
socket_address:
address: 1.2.3.4
port_value: 8080
- priority: 1
lb_endpoints:
- endpoint:
address:
socket_address:
address: 6.7.8.9
port_value: 8080
Mesh gateways route requests based solely on the SNI header tacked onto
the TLS layer. Envoy currently only lets you configure the outbound SNI
header at the cluster layer.
If you try to failover through a mesh gateway you ideally would
configure the SNI value per endpoint, but that's not possible in envoy
today.
This PR introduces a simpler way around the problem for now:
1. We identify any target of failover that will use mesh gateway mode local or
remote and then further isolate any resolver node in the compiled discovery
chain that has a failover destination set to one of those targets.
2. For each of these resolvers we will perform a small measurement of
comparative healths of the endpoints that come back from the health API for the
set of primary target and serial failover targets. We walk the list of targets
in order and if any endpoint is healthy we return that target, otherwise we
move on to the next target.
3. The CDS and EDS endpoints both perform the measurements in (2) for the
affected resolver nodes.
4. For CDS this measurement selects which TLS SNI field to use for the cluster
(note the cluster is always going to be named for the primary target)
5. For EDS this measurement selects which set of endpoints will populate the
cluster. Priority tiered failover is ignored.
One of the big downsides to this approach to failover is that the failover
detection and correction is going to be controlled by consul rather than
deferring that entirely to the data plane as with the prior version. This also
means that we are bound to only failover using official health signals and
cannot make use of data plane signals like outlier detection to affect
failover.
In this specific scenario the lack of data plane signals is ok because the
effectiveness is already muted by the fact that the ultimate destination
endpoints will have their data plane signals scrambled when they pass through
the mesh gateway wrapper anyway so we're not losing much.
Another related fix is that we now use the endpoint health from the
underlying service, not the health of the gateway (regardless of
failover mode).
In addition to exposing compilation over the API cleaned up the structures that would be exchanged to be cleaner and easier to support and understand.
Also removed ability to configure the envoy OverprovisioningFactor.
This should make them better for sending over RPC or the API.
Instead of a chain implemented explicitly like a linked list (nodes
holding pointers to other nodes) instead switch to a flat map of named
nodes with nodes linking other other nodes by name. The shipped
structure is just a map and a string to indicate which key to start
from.
Other changes:
* inline the compiler option InferDefaults as true
* introduce compiled target config to avoid needing to send back
additional maps of Resolvers; future target-specific compiled state
can go here
* move compiled MeshGateway out of the Resolver and into the
TargetConfig where it makes more sense.
* connect: reconcile how upstream configuration works with discovery chains
The following upstream config fields for connect sidecars sanely
integrate into discovery chain resolution:
- Destination Namespace/Datacenter: Compilation occurs locally but using
different default values for namespaces and datacenters. The xDS
clusters that are created are named as they normally would be.
- Mesh Gateway Mode (single upstream): If set this value overrides any
value computed for any resolver for the entire discovery chain. The xDS
clusters that are created may be named differently (see below).
- Mesh Gateway Mode (whole sidecar): If set this value overrides any
value computed for any resolver for the entire discovery chain. If this
is specifically overridden for a single upstream this value is ignored
in that case. The xDS clusters that are created may be named differently
(see below).
- Protocol (in opaque config): If set this value overrides the value
computed when evaluating the entire discovery chain. If the normal chain
would be TCP or if this override is set to TCP then the result is that
we explicitly disable L7 Routing and Splitting. The xDS clusters that
are created may be named differently (see below).
- Connect Timeout (in opaque config): If set this value overrides the
value for any resolver in the entire discovery chain. The xDS clusters
that are created may be named differently (see below).
If any of the above overrides affect the actual result of compiling the
discovery chain (i.e. "tcp" becomes "grpc" instead of being a no-op
override to "tcp") then the relevant parameters are hashed and provided
to the xDS layer as a prefix for use in naming the Clusters. This is to
ensure that if one Upstream discovery chain has no overrides and
tangentially needs a cluster named "api.default.XXX", and another
Upstream does have overrides for "api.default.XXX" that they won't
cross-pollinate against the operator's wishes.
Fixes#6159
* connect: validate upstreams and prevent duplicates
* Actually run Upstream.Validate() instead of ignoring it as dead code.
* Prevent two upstreams from declaring the same bind address and port.
It wouldn't work anyway.
* Prevent two upstreams from being declared that use the same
type+name+namespace+datacenter. Due to how the Upstream.Identity()
function worked this ended up mostly being enforced in xDS at use-time,
but it should be enforced more clearly at register-time.
Secondary CA initialization steps are:
• Wait until the primary will be capable of signing intermediate certs. We use serf metadata to check the versions of servers in the primary which avoids needing a token like the previous implementation that used RPCs. We require at least one alive server in the primary and the all alive servers meet the version requirement.
• Initialize the secondary CA by getting the primary to sign an intermediate
When a primary dc is configured, if no existing CA is initialized and for whatever reason we cannot initialize a secondary CA the secondary DC will remain without a CA. As soon as it can it will initialize the secondary CA by pulling the primaries roots and getting the primary to sign an intermediate.
This also fixes a segfault that can happen during leadership revocation. There was a spot in the secondaryCARootsWatch that was getting the CA Provider and executing methods on it without nil checking. Under normal circumstances it wont be nil but during leadership revocation it gets nil'ed out. Therefore there is a period of time between closing the stop chan and when the go routine is actually stopped where it could read a nil provider and cause a segfault.
Auto-encrypt meant to fallback to the default port when it wasn't provided, but it hadn't been because of an issue with the error handling. We were checking against an incomplete error value:
"missing port in address" vs "address $HOST: missing port in address"
Additionally, all RPCs to AutoEncrypt.Sign were using a.config.ServerPort, so those were updated to use ports resolved by resolveAddrs, if they are available.
* Allow setting the mesh gateway mode for an upstream in config files
* Add envoy integration test for mesh gateways
This necessitated many supporting changes in most of the other test cases.
Add remote mode mesh gateways integration test
The main change is that we no longer filter service instances by health,
preferring instead to render all results down into EDS endpoints in
envoy and merely label the endpoints as HEALTHY or UNHEALTHY.
When OnlyPassing is set to true we will force consul checks in a
'warning' state to render as UNHEALTHY in envoy.
Fixes#6171
* Display nicely Networks (CIDR) in runtime configuration
CIDR mask is displayed in binary in configuration.
This add support for nicely displaying CIDR in runtime configuration.
Currently, if a configuration contains the following lines:
"http_config": {
"allow_write_http_from": [
"127.0.0.0/8",
"::1/128"
]
}
A call to `/v1/agent/self?pretty` would display
"AllowWriteHTTPFrom": [
{
"IP": "127.0.0.0",
"Mask": "/wAAAA=="
},
{
"IP": "::1",
"Mask": "/////////////////////w=="
}
]
This PR fixes it and it will now display:
"AllowWriteHTTPFrom": [ "127.0.0.0/8", "::1/128" ]
* Added test for cidr nice rendering in `TestSanitize()`.
* Update go-bexpr to v0.1.1
This brings in:
• `in`/`not in` operators to do substring matching
• `matches` / `not matches` operators to perform regex string matching.
* Add the capability to auto-generate the filtering selector ops tables for our docs
This fixes pathological cases where the write throughput and snapshot size are both so large that more than 10k log entries are written in the time it takes to restore the snapshot from disk. In this case followers that restart can never catch up with leader replication again and enter a loop of constantly downloading a full snapshot and restoring it only to find that snapshot is already out of date and the leader has truncated its logs so a new snapshot is sent etc.
In general if you need to adjust this, you are probably abusing Consul for purposes outside its design envelope and should reconsider your usage to reduce data size and/or write volume.
All these changes should have no side-effects or change behavior:
- Use bytes.Buffer's String() instead of a conversion
- Use time.Since and time.Until where fitting
- Drop unnecessary returns and assignment
I can only assume we want to check for the retrieved `updatedToken` to not be
nil, before accessing it below.
`token` can't possibly be nil at this point, as we accessed `token.AccessorID`
just before.
* Ensure the mesh gateway configuration comes back in the api within each upstream
* Add a test for the MeshGatewayConfig in the ToAPI functions
* Ensure we don’t use gateways for dc local connections
* Update the svc kind index for deletions
* Replace the proxycfg.state cache with an interface for testing
Also start implementing proxycfg state testing.
* Update the state tests to verify some gateway watches for upstream-targets of a discovery chain.
Also:
- add back an internal http endpoint to dump a compiled discovery chain for debugging purposes
Before the CompiledDiscoveryChain.IsDefault() method would test:
- is this chain just one resolver step?
- is that resolver step just the default?
But what I forgot to test:
- is that resolver step for the same service that the chain represents?
This last point is important because if you configured just one config
entry:
kind = "service-resolver"
name = "web"
redirect {
service = "other"
}
and requested the chain for "web" you'd get back a **default** resolver
for "other". In the xDS code the IsDefault() method is used to
determine if this chain is "empty". If it is then we use the
pre-discovery-chain logic that just uses data embedded in the Upstream
object (and still lets the escape hatches function).
In the example above that means certain parts of the xDS code were going
to try referencing a cluster named "web..." despite the other parts of
the xDS code maintaining clusters named "other...".
Both 'consul config write' and server bootstrap config entries take a
decoding detour through mapstructure on the way from HCL to an actual
struct. They both may take in snake_case or CamelCase (for consistency)
so need very similar handling.
Unfortunately since they are operating on mirror universes of structs
(api.* vs structs.*) the code cannot be identitical, so try to share the
kind-configuration and duplicate the rest for now.
* Ensure we MapWalk the proxy config in the NodeService and ServiceNode structs
This gets rid of some json encoder errors in the catalog endpoints
* Allow passing explicit bind addresses to envoy
* Move map walking to the ConnectProxyConfig struct
Any place where this struct gets JSON encoded will benefit as opposed to having to implement it everywhere.
* Fail when a non-empty address is provided and not bindable
* camel case
* Update command/connect/envoy/envoy.go
Co-Authored-By: Paul Banks <banks@banksco.de>
* Retry the creation of the test server three times.
* Reduce the retry timeout for the API wait to 2 seconds, opting to fail faster and start over.
* Remove wait for leader from server creation. This wait can be added on a test by test basis now that the function is being exported.
* Remove wait for anti-entropy sync. This is built into the existing WaitForSerfCheck func, so that can be used if the anti-entropy wait is needed
Previously a sequence of events like:
Start
Stop
Start
Stop
would segfault on the second stop because the original ctx and cancel func were only initialized during the constructor and not during Start.
* Make cluster names SNI always
* Update some tests
* Ensure we check for prepared query types
* Use sni for route cluster names
* Proper mesh gateway mode defaulting when the discovery chain is used
* Ignore service splits from PatchSliceOfMaps
* Update some xds golden files for proper test output
* Allow for grpc/http listeners/cluster configs with the disco chain
* Update stats expectation
* connect: allow overriding envoy listener bind_address
* Update agent/xds/config.go
Co-Authored-By: Kyle Havlovitz <kylehav@gmail.com>
* connect: allow overriding envoy listener bind_port
* envoy: support unix sockets for grpc in bootstrap
Add AgentSocket BootstrapTplArgs which if set overrides the AgentAddress
and AgentPort to generate a bootstrap which points Envoy to a unix
socket file instead of an ip:port.
* Add a test for passing the consul addr as a unix socket
* Fix config formatting for envoy bootstrap tests
* Fix listeners test cases for bind addr/port
* Update website/source/docs/connect/proxies/envoy.md
maxIndexWatchTxn was only watching the IndexEntry of the max index of all the entries. It needed to watch all of them regardless of which was the max.
Also plumbed the query source through in the proxy config to help better track requests.
The clusters/endpoints test were still relying on deterministic ordering of clusters/endpoints which cannot be relied upon due to golang purposefully not providing any guarantee about consistent interation ordering of maps.
Also fixed a small bug in the connect proxy cluster generation that was causing the clusters slice to be double the size it needed to with the first half being all nil pointers.
* Fix some tests that I broke when refactoring the ConfigSnapshot
* Make sure the MeshGateway config is added to all the right api structs
* Fix some more tests
The general problem was that a the CA config which contained the trust domain was happening outside of the blocking mechanism so if the client started the blocking query before the primary dcs roots had been set then a state trust domain was being pushed down.
This was fixed here but in the future we should probably fixup the CA initialization code to not initialize the CA config twice when it doesn’t need to.
* Prune Servers from WAN and LAN
* cleaned up and fixed LAN to WAN
* moving things around
* force-leave remove from serfWAN, create pruneSerfWAN
* removed serfWAN remove, reduced complexity, fixed comments
* add another place to remove from serfWAN
* add nil check
* Update agent/consul/server.go
Co-Authored-By: Paul Banks <banks@banksco.de>
With this you should be able to fetch all of the relevant discovery
chain config entries from the state store in one query and then feed
them into the compiler outside of a transaction.
There are a lot of TODOs scattered through here, but they're mostly
around handling fun edge cases and can be deferred until more of the
plumbing works completely.
With ACLs enabled if an agent is wiped and restarted without a leave
it can no longer deregister the services it had previously registered
because it no longer has the tokens the services were registered with.
To remedy that we allow service deregistration from tokens with node
write permission.
* Add ui-content-path flag
* tests complete, regex validator on string, index.html updated
* cleaning up debugging stuff
* ui: Enable ember environment configuration to be set via the go binary at runtime (#5934)
* ui: Only inject {{.ContentPath}} if we are makeing a prod build...
...otherwise we just use the current rootURL
This gets injected into a <base /> node which solves the assets path
problem but not the ember problem
* ui: Pull out the <base href=""> value and inject it into ember env
See previous commit:
The <base href=""> value is 'sometimes' injected from go at index
serve time. We pass this value down to ember by overwriting the ember
config that is injected via a <meta> tag. This has to be done before
ember bootup.
Sometimes (during testing and development, basically not production)
this is injected with the already existing value, in which case this
essentially changes nothing.
The code here is slightly abstracted away from our specific usage to
make it easier for anyone else to use, and also make sure we can cope
with using this same method to pass variables down from the CLI through
to ember in the future.
* ui: We can't use <base /> move everything to javascript (#5941)
Unfortuantely we can't seem to be able to use <base> and rootURL
together as URL paths will get doubled up (`ui/ui/`).
This moves all the things that we need to interpolate with .ContentPath
to the `startup` javascript so we can conditionally print out
`{{.ContentPath}}` in lots of places (now we can't use base)
* fixed when we serve index.html
* ui: For writing a ContentPath, we also need to cope with testing... (#5945)
...and potentially more environments
Testing has more additional things in a separate index.html in `tests/`
This make the entire thing a little saner and uses just javascriopt
template literals instead of a pseudo handbrake synatx for our
templating of these files.
Intead of just templating the entire file this way, we still only
template `{{content-for 'head'}}` and `{{content-for 'body'}}`
in this way to ensure we support other plugins/addons
* build: Loosen up the regex for retrieving the CONSUL_VERSION (#5946)
* build: Loosen up the regex for retrieving the CONSUL_VERSION
1. Previously the `sed` replacement was searching for the CONSUL_VERSION
comment at the start of a line, it no longer does this to allow for
indentation.
2. Both `grep` and `sed` where looking for the omment at the end of the
line. We've removed this restriction here. We don't need to remove it
right now, but if we ever put the comment followed by something here the
searching would break.
3. Added `xargs` for trimming the resulting version string. We aren't
using this already in the rest of the scripts, but we are pretty sure
this is available on most systems.
* ui: Fix erroneous variable, and also force an ember cache clean on build
1. We referenced a variable incorrectly here, this fixes that.
2. We also made sure that every `make` target clears ember's `tmp` cache
to ensure that its not using any caches that have since been edited
everytime we call a `make` target.
* added docs, fixed encoding
* fixed go fmt
* Update agent/config/config.go
Co-Authored-By: R.B. Boyer <public@richardboyer.net>
* Completed Suggestions
* run gofmt on http.go
* fix testsanitize
* fix fullconfig/hcl by setting correct 'want'
* ran gofmt on agent/config/runtime_test.go
* Update website/source/docs/agent/options.html.md
Co-Authored-By: Hans Hasselberg <me@hans.io>
* Update website/source/docs/agent/options.html.md
Co-Authored-By: kaitlincarter-hc <43049322+kaitlincarter-hc@users.noreply.github.com>
* remove contentpath from redirectFS struct
* Support for maximum size for Output of checks
This PR allows users to limit the size of output produced by checks at the agent
and check level.
When set at the agent level, it will limit the output for all checks monitored
by the agent.
When set at the check level, it can override the agent max for a specific check but
only if it is lower than the agent max.
Default value is 4k, and input must be at least 1.
If a KVSet is performed but does not update the entry, do not trigger
watches for this key.
This avoids releasing blocking queries for KV values that did not
actually changed.
Read requests performed during anti antropy full sync currently target
the leader only. This generates a non-negligible load on the leader when
the DC is large enough and can be offloaded to the followers following
the "eventually consistent" policy for the agent state.
We switch the AE read calls to use stale requests with a small (2s)
MaxStaleDuration value and make sure we do not read too fast after a
write.
This allows addresses to be tagged at the service level similar to what we allow for nodes already. The address translation that can be enabled with the `translate_wan_addrs` config was updated to take these new addresses into account as well.
* Upgrade xDS (go-control-plane) API to support Envoy 1.10.
This includes backwards compatibility shim to work around the ext_authz package rename in 1.10.
It also adds integration test support in CI for 1.10.0.
* Fix go vet complaints
* go mod vendor
* Update Envoy version info in docs
* Update website/source/docs/connect/proxies/envoy.md
The observed bug was that a full restart of a consul datacenter (servers
and clients) in conjunction with a restart of a connect-flavored
application with bring-your-own-service-registration logic would very
frequently cause the envoy sidecar service check to never reflect the
aliased service.
Over the course of investigation several bugs and unfortunate
interactions were corrected:
(1)
local.CheckState objects were only shallow copied, but the key piece of
data that gets read and updated is one of the things not copied (the
underlying Check with a Status field). When the stock code was run with
the race detector enabled this highly-relevant-to-the-test-scenario field
was found to be racy.
Changes:
a) update the existing Clone method to include the Check field
b) copy-on-write when those fields need to change rather than
incrementally updating them in place.
This made the observed behavior occur slightly less often.
(2)
If anything about how the runLocal method for node-local alias check
logic was ever flawed, there was no fallback option. Those checks are
purely edge-triggered and failure to properly notice a single edge
transition would leave the alias check incorrect until the next flap of
the aliased check.
The change was to introduce a fallback timer to act as a control loop to
double check the alias check matches the aliased check every minute
(borrowing the duration from the non-local alias check logic body).
This made the observed behavior eventually go away when it did occur.
(3)
Originally I thought there were two main actions involved in the data race:
A. The act of adding the original check (from disk recovery) and its
first health evaluation.
B. The act of the HTTP API requests coming in and resetting the local
state when re-registering the same services and checks.
It took awhile for me to realize that there's a third action at work:
C. The goroutines associated with the original check and the later
checks.
The actual sequence of actions that was causing the bad behavior was
that the API actions result in the original check to be removed and
re-added _without waiting for the original goroutine to terminate_. This
means for brief windows of time during check definition edits there are
two goroutines that can be sending updates for the alias check status.
In extremely unlikely scenarios the original goroutine sees the aliased
check start up in `critical` before being removed but does not get the
notification about the nearly immediate update of that check to
`passing`.
This is interlaced wit the new goroutine coming up, initializing its
base case to `passing` from the current state and then listening for new
notifications of edge triggers.
If the original goroutine "finishes" its update, it then commits one
more write into the local state of `critical` and exits leaving the
alias check no longer reflecting the underlying check.
The correction here is to enforce that the old goroutines must terminate
before spawning the new one for alias checks.
* Improve startup message to avoid confusing users when no error occurs
Several times, some users not very familiar with Consul get confused
by error message at startup:
`[INFO] agent: (LAN) joined: 1 Err: <nil>`
Having `Err: <nil>` seems weird to many users, I propose to have the
following instead:
* Success: `[INFO] agent: (LAN) joined: 1`
* Error: `[WARN] agent: (LAN) couldn't join: %d Err: ERROR`
Logic updated to evaluate with a boolean after the type assertion.
This allows us to check if the type assertion succeeded and be
more clear with errors.
* Fix race condition during a cache get
Check the entry we pulled out of the cache while holding the lock had Fetching set.
If it did then we should use the existing Waiter instead of calling fetch. The reason
this is better than just calling fetch is that fetch re-gets the entry out of the
entries map and the previous fetch may have finished. Therefore this prevents
erroneously starting a new fetch because we just missed the last update.
* Fix race condition fully
The first commit still allowed for the following scenario:
• No entry existing when checked in getWithIndex while holding the read lock
• Then by time we had reached fetch it had been created and finished.
* always use ok when returning
* comment mentioning the reading from entries.
* use cacheHit consistently
* Add integration test for central config; fix central config WIP
* Add integration test for central config; fix central config WIP
* Set proxy protocol correctly and begin adding upstream support
* Add upstreams to service config cache key and start new notify watcher if they change.
This doesn't update the tests to pass though.
* Fix some merging logic get things working manually with a hack (TODO fix properly)
* Simplification to not allow enabling sidecars centrally - it makes no sense without upstreams anyway
* Test compile again and obvious ones pass. Lots of failures locally not debugged yet but may be flakes. Pushing up to see what CI does
* Fix up service manageer and API test failures
* Remove the enable command since it no longer makes much sense without being able to turn on sidecar proxies centrally
* Remove version.go hack - will make integration test fail until release
* Remove unused code from commands and upstream merge
* Re-bump version to 1.5.0
* Add HTTP endpoints for config entry management
* Finish implementing decoding in the HTTP Config entry apply endpoint
* Add CAS operation to the config entry apply endpoint
Also use this for the bootstrapping and move the config entry decoding function into the structs package.
* First pass at the API client for the config entries
* Fixup some of the ConfigEntry APIs
Return a singular response object instead of a list for the ConfigEntry.Get RPC. This gets plumbed through the HTTP API as well.
Dont return QueryMeta in the JSON response for the config entry listing HTTP API. Instead just return a list of config entries.
* Minor API client fixes
* Attempt at some ConfigEntry api client tests
These don’t currently work due to weak typing in JSON
* Get some of the api client tests passing
* Implement reflectwalk magic to correct JSON encoding a ProxyConfigEntry
Also added a test for the HTTP endpoint that exposes the problem. However, since the test doesn’t actually do the JSON encode/decode its still failing.
* Move MapWalk magic into a binary marshaller instead of JSON.
* Add a MapWalk test
* Get rid of unused func
* Get rid of unused imports
* Fixup some tests now that the decoding from msgpack coerces things into json compat types
* Stub out most of the central config cli
Fully implement the config read command.
* Basic config delete command implementation
* Implement config write command
* Implement config list subcommand
Not entirely sure about the output here. Its basically the read output indented with a line specifying the kind/name of each type which is also duplicated in the indented output.
* Update command usage
* Update some help usage formatting
* Add the connect enable helper cli command
* Update list command output
* Rename the config entry API client methods.
* Use renamed apis
* Implement config write tests
Stub the others with the noTabs tests.
* Change list output format
Now just simply output 1 line per named config
* Add config read tests
* Add invalid args write test.
* Add config delete tests
* Add config list tests
* Add connect enable tests
* Update some CLI commands to use CAS ops
This also modifies the HTTP API for a write op to return a boolean indicating whether the value was written or not.
* Fix up the HTTP API CAS tests as I realized they weren’t testing what they should.
* Update config entry rpc tests to properly test CAS
* Fix up a few more tests
* Fix some tests that using ConfigEntries.Apply
* Update config_write_test.go
* Get rid of unused import
Also update some snapshot agent docs
* Enforce correct permissions when registering a check
Previously we had attempted to enforce service:write for a check associated with a service instead of node:write on the agent but due to how we decoded the health check from the request it would never do it properly. This commit fixes that.
* Update website/source/docs/commands/snapshot/agent.html.markdown.erb
Co-Authored-By: mkeeler <mkeeler@users.noreply.github.com>
* Add support for HTTP proxy listeners
* Add customizable bootstrap configuration options
* Debug logging for xDS AuthZ
* Add Envoy Integration test suite with basic test coverage
* Add envoy command tests to cover new cases
* Add tracing integration test
* Add gRPC support WIP
* Merged changes from master Docker. get CI integration to work with same Dockerfile now
* Make docker build optional for integration
* Enable integration tests again!
* http2 and grpc integration tests and fixes
* Fix up command config tests
* Store all container logs as artifacts in circle on fail
* Add retries to outer part of stats measurements as we keep missing them in CI
* Only dump logs on failing cases
* Fix typos from code review
* Review tidying and make tests pass again
* Add debug logs to exec test.
* Fix legit test failure caused by upstream rename in envoy config
* Attempt to reduce cases of bad TLS handshake in CI integration tests
* bring up the right service
* Add prometheus integration test
* Add test for denied AuthZ both HTTP and TCP
* Try ANSI term for Circle
When receiving a serf faild message for a node which is not in the
catalog, do not perform a register request to set is serf heath to
critical as it could overwrite the node information and services if it
was renamed.
Fixes : #5518
Roles are named and can express the same bundle of permissions that can
currently be assigned to a Token (lists of Policies and Service
Identities). The difference with a Role is that it not itself a bearer
token, but just another entity that can be tied to a Token.
This lets an operator potentially curate a set of smaller reusable
Policies and compose them together into reusable Roles, rather than
always exploding that same list of Policies on any Token that needs
similar permissions.
This also refactors the acl replication code to be semi-generic to avoid
3x copypasta.
This is mainly to avoid having the API return "0001-01-01T00:00:00Z" as
a value for the ExpirationTime field when it is not set. Unfortunately
time.Time doesn't respect the json marshalling "omitempty" directive.
These act like a special cased version of a Policy Template for granting
a token the privileges necessary to register a service and its connect
proxy, and read upstreams from the catalog.
* Move the watch package into the api module
It was already just a thin wrapper around the API anyways. The biggest change was to the testing. Instead of using a test agent directly from the agent package it now uses the binary on the PATH just like the other API tests.
The other big changes were to fix up the connect based watch tests so that we didn’t need to pull in the connect package (and therefore all of Consul)
The DNS config parameters `recursors` and `dns_config.*` are now hot
reloaded on SIGHUP or `consul reload` and do not need an agent restart
to be modified.
Config is stored in an atomic.Value and loaded at the beginning of each
request. Reloading only affects requests that start _after_ the
reload. Ongoing requests are not affected. To match the current
behavior the recursor handler is loaded and unloaded as needed on config
reload.
Due to an unintended order of operations issue with integer division
TestSessionTTLRenew was sleeping for 0s every time.
Also add explicit failures for when the various session renewal returns
nil unexpectedly.
Fixes: #4222
# Data Filtering
This PR will implement filtering for the following endpoints:
## Supported HTTP Endpoints
- `/agent/checks`
- `/agent/services`
- `/catalog/nodes`
- `/catalog/service/:service`
- `/catalog/connect/:service`
- `/catalog/node/:node`
- `/health/node/:node`
- `/health/checks/:service`
- `/health/service/:service`
- `/health/connect/:service`
- `/health/state/:state`
- `/internal/ui/nodes`
- `/internal/ui/services`
More can be added going forward and any endpoint which is used to list some data is a good candidate.
## Usage
When using the HTTP API a `filter` query parameter can be used to pass a filter expression to Consul. Filter Expressions take the general form of:
```
<selector> == <value>
<selector> != <value>
<value> in <selector>
<value> not in <selector>
<selector> contains <value>
<selector> not contains <value>
<selector> is empty
<selector> is not empty
not <other expression>
<expression 1> and <expression 2>
<expression 1> or <expression 2>
```
Normal boolean logic and precedence is supported. All of the actual filtering and evaluation logic is coming from the [go-bexpr](https://github.com/hashicorp/go-bexpr) library
## Other changes
Adding the `Internal.ServiceDump` RPC endpoint. This will allow the UI to filter services better.
* First conversion
* Use serf 0.8.2 tag and associated updated deps
* * Move freeport and testutil into internal/
* Make internal/ its own module
* Update imports
* Add replace statements so API and normal Consul code are
self-referencing for ease of development
* Adapt to newer goe/values
* Bump to new cleanhttp
* Fix ban nonprintable chars test
* Update lock bad args test
The error message when the duration cannot be parsed changed in Go 1.12
(ae0c435877d3aacb9af5e706c40f9dddde5d3e67). This updates that test.
* Update another test as well
* Bump travis
* Bump circleci
* Bump go-discover and godo to get rid of launchpad dep
* Bump dockerfile go version
* fix tar command
* Bump go-cleanhttp
* Connect: Fix Envoy getting stuck during load
Also in this PR:
- Enabled outlier detection on upstreams which will mark instances unhealthy after 5 failures (using Envoy's defaults)
- Enable weighted load balancing where DNS weights are configured
* Fix empty load assignments in the right place
* Fix import names from review
* Move millisecond parse to a helper function
* Make Connect health queryies unblock correctly in all cases and use optimal number of watch chans. Fixes#5506.
* Node check test cases and clearer bug test doc
* Comment update
Refs #4984.
Watching chans for every node we touch in a health query is wasteful. In #4984 it shows that if there are more than 682 service instances we always fallback to watching all services which kills performance.
We already have a record in MemDB that is reliably update whenever the service health result should change thanks to per-service watch indexes.
So in general, provided there is at least one service instances and we actually have a service index for it (we always do now) we only ever need to watch a single channel.
This saves us from ever falling back to the general index and causing the performance cliff in #4984, but it also means fewer goroutines and work done for every blocking health query.
It also saves some allocations made during the query because we no longer have to populate a WatchSet with 3 chans per service instance which saves the internal map allocation.
This passes all state store tests except the one that explicitly checked for the fallback behaviour we've now optimized away and in general seems safe.
acl: reduce complexity of token resolution process with alternative singleflighting
Switches acl resolution to use golang.org/x/sync/singleflight. For the
identity/legacy lookups this is a drop-in replacement with the same
overall approach to request coalescing.
For policies this is technically a change in behavior, but when
considered holistically is approximately performance neutral (with the
benefit of less code).
There are two goals with this blob of code (speaking specifically of
policy resolution here):
1) Minimize cross-DC requests.
2) Minimize client-to-server LAN requests.
The previous iteration of this code was optimizing for the case of many
possibly different tokens being resolved concurrently that have a
significant overlap in linked policies such that deduplication would be
worth the complexity. While this is laudable there are some things to
consider that can help to adjust expectations:
1) For v1.4+ policies are always replicated, and once a single policy
shows up in a secondary DC the replicated data is considered
authoritative for requests made in that DC. This means that our
earlier concerns about minimizing cross-DC requests are irrelevant
because there will be no cross-DC policy reads that occur.
2) For Server nodes the in-memory ACL policy cache is capped at zero,
meaning it has no caching. Only Client nodes run with a cache. This
means that instead of having an entire DC's worth of tokens (what a
Server might see) that can have policy resolutions coalesced these
nodes will only ever be seeing node-local token resolutions. In a
reasonable worst-case scenario where a scheduler like Kubernetes has
"filled" a node with Connect services, even that will only schedule
~100 connect services per node. If every service has a unique token
there will only be 100 tokens to coalesce and even then those requests
have to occur concurrently AND be hitting an empty consul cache.
Instead of seeing a great coalescing opportunity for cutting down on
redundant Policy resolutions, in practice it's far more likely given
node densities that you'd see requests for the same token concurrently
than you would for two tokens sharing a policy concurrently (to a degree
that would warrant the overhead of the current variation of
singleflighting.
Given that, this patch switches the Policy resolution process to only
singleflight by requesting token (but keeps the cache as by-policy).
This PR introduces reloading tls configuration. Consul will now be able to reload the TLS configuration which previously required a restart. It is not yet possible to turn TLS ON or OFF with these changes. Only when TLS is already turned on, the configuration can be reloaded. Most importantly the certificates and CAs.
Node updates were not updating the service indexes, which are used for
service related queries. This caused the X-Consul-Index to stay the same
after a node update as seen from a service query even though the node
data is returned in heath queries. If that happened in between queries
the client would miss this change.
We now update the indexes of the services on the node when it is
updated.
Fixes: #5450
In TestServer_LANReap autopilot is running, so the alternate flow
through the serf reaping function is possible. In that situation the
ReconnectTimeout is not relevant so for parity also override the
TombstoneTimeout value as well.
For additional parity update the TestServer_WANReap and
TestClient_LANReap versions of this test in the same way even though
autopilot is irrelevant here .
Fix error in detecting raft replication errors.
Detect redacted token secrets and prevent attempting to insert.
Add a Redacted field to the TokenBatchRead and TokenRead RPC endpoints
This will indicate whether token secrets have been redacted.
Ensure any token with a redacted secret in secondary datacenters is removed.
Test that redacted tokens cannot be replicated.
Prevent race between register and deregister requests by saving them
together in the local state on registration.
Also adds more cleaning in case of failure when registering services
/ checks.
Previously we were fixing up the token links directly on the *ACLToken returned by memdb. This invalidated some assumptions that a snapshot is immutable as well as potentially being able to cause a crash.
The fix here is to give the policy link fixing function copy on write semantics. When no fixes are necessary we can return the memdb object directly, otherwise we copy it and create a new list of links.
Eventually we might find a better way to keep those policy links in sync but for now this fixes the issue.
* Fix race condition in DNS when using cache
The healty node filtering was modifying the result from the cache, which
caused a crash when multiple queries were made to the same service
simultaneously.
We now copy the node slice before filtering to ensure we do not modify
the data stored in the cache.
* Fix wording in dns cache config doc
s/dns_max_age/cache_max_age/
This PR adds two features which will be useful for operators when ACLs are in use.
1. Tokens set in configuration files are now reloadable.
2. If `acl.enable_token_persistence` is set to `true` in the configuration, tokens set via the `v1/agent/token` endpoint are now persisted to disk and loaded when the agent starts (or during configuration reload)
Note that token persistence is opt-in so our users who do not want tokens on the local disk will see no change.
Some other secondary changes:
* Refactored a bunch of places where the replication token is retrieved from the token store. This token isn't just for replicating ACLs and now it is named accordingly.
* Allowed better paths in the `v1/agent/token/` API. Instead of paths like: `v1/agent/token/acl_replication_token` the path can now be just `v1/agent/token/replication`. The old paths remain to be valid.
* Added a couple new API functions to set tokens via the new paths. Deprecated the old ones and pointed to the new names. The names are also generally better and don't imply that what you are setting is for ACLs but rather are setting ACL tokens. There is a minor semantic difference there especially for the replication token as again, its no longer used only for ACL token/policy replication. The new functions will detect 404s and fallback to using the older token paths when talking to pre-1.4.3 agents.
* Docs updated to reflect the API additions and to show using the new endpoints.
* Updated the ACL CLI set-agent-tokens command to use the non-deprecated APIs.
This PR is based on #5366 and continues to centralise the tls configuration in order to be reloadable eventually!
This PR is another refactoring. No tests are changed, beyond calling other functions or cosmetic stuff. I added a bunch of tests, even though they might be redundant.
In order to be able to reload the TLS configuration, we need one way to generate the different configurations.
This PR introduces a `tlsutil.Configurator` which holds a `tlsutil.Config`. Afterwards it is responsible for rendering every `tls.Config`. In this particular PR I moved `IncomingHTTPSConfig`, `IncomingTLSConfig`, and `OutgoingTLSWrapper` into `tlsutil.Configurator`.
This PR is a pure refactoring - not a single feature added. And not a single test added. I only slightly modified existing tests as necessary.
Adds two new configuration parameters "dns_config.use_cache" and
"dns_config.cache_max_age" controlling how DNS requests use the agent
cache when querying servers.
* Start adding tests for cluster override
* Refactor tests for clusters
* Passing tests for custom upstream cluster override
* Added capability to customise local app cluster
* Rename config for local cluster override
Also in acl_endpoint_test.go:
* convert logical blocks in some token tests to subtests
* remove use of require.New
This removes a lot of noise in a later PR.
This way we can avoid unnecessary panics which cause other tests not to run.
This doesn't remove all the possibilities for panics causing other tests not to run, it just fixes the TestAgent
Currently the gRPC server assumes that if you have configured TLS
certs on the agent (for RPC) that you want gRPC to be encrypted.
If gRPC is bound to localhost this can be overkill. For the API we
let the user choose to offer HTTP or HTTPS API endpoints
independently of the TLS cert configuration for a similar reason.
This setting will let someone encrypt RPC traffic with TLS but avoid
encrypting local gRPC traffic if that is what they want to do by only
enabling TLS on gRPC if the HTTPS API port is enabled.
There was an errant early-return in PolicyDelete() that bypassed the
rest of the function. This was ok because the only caller of this
function ignores the results.
This removes the early-return making it structurally behave like
TokenDelete() and for both PolicyDelete and TokenDelete clarify the lone
callers to indicate that the return values are ignored.
We may wish to avoid the entire return value as well, but this patch
doesn't go that far.
`establishLeadership` invoked during leadership monitoring may use autopilot to do promotions etc. There was a race with doing that and having autopilot initialized and this fixes it.
Given a query like:
```
{
"Name": "tagged-connect-query",
"Service": {
"Service": "foo",
"Tags": ["tag"],
"Connect": true
}
}
```
And a Consul configuration like:
```
{
"services": [
"name": "foo",
"port": 8080,
"connect": { "sidecar_service": {} },
"tags": ["tag"]
]
}
```
If you executed the query it would always turn up with 0 results. This was because the sidecar service was being created without any tags. You could instead make your config look like:
```
{
"services": [
"name": "foo",
"port": 8080,
"connect": { "sidecar_service": {
"tags": ["tag"]
} },
"tags": ["tag"]
]
}
```
However that is a bit redundant for most cases. This PR ensures that the tags and service meta of the parent service get copied to the sidecar service. If there are any tags or service meta set in the sidecar service definition then this copying does not take place. After the changes, the query will now return the expected results.
A second change was made to prepared queries in this PR which is to allow filtering on ServiceMeta just like we allow for filtering on NodeMeta.
When tests fail, only the logs for the failing run are dumped to the
console which helps in diagnosis. This is easily added to other test
scenarios as they come up.
* Fix 2 remote ACL policy resolution issues
1 - Use the right method to fire async not found errors when the ACL.PolicyResolve RPC returns that error. This was previously accidentally firing a token result instead of a policy result which would have effectively done nothing (unless there happened to be a token with a secret id == the policy id being resolved.
2. When concurrent policy resolution is being done we single flight the requests. The bug before was that for the policy resolution that was going to piggy back on anothers RPC results it wasn’t waiting long enough for the results to come back due to looping with the wrong variable.
* Fix a handful of other edge case ACL scenarios
The main issue was that token specific issues (not able to access a particular policy or the token being deleted after initial fetching) were poisoning the policy cache.
A second issue was that for concurrent token resolutions, the first resolution to get started would go fetch all the policies. If before the policies were retrieved a second resolution request came in, the new request would register watchers for those policies but then never block waiting for them to complete. This resulted in using the default policy when it shouldn't have.
* Support rate limiting and concurrency limiting CSR requests on servers; handle CA rotations gracefully with jitter and backoff-on-rate-limit in client
* Add CSR rate limiting docs
* Fix config naming and add tests for new CA configs
For established xDS gRPC streams recheck ACLs for each DiscoveryRequest
or DiscoveryResponse. If more than 5 minutes has elapsed since the last
ACL check, recheck even without an incoming DiscoveryRequest or
DiscoveryResponse. ACL failures will terminate the stream.
Fixes#4969
This implements non-blocking request polling at the cache layer which is currently only used for prepared queries. Additionally this enables the proxycfg manager to poll prepared queries for use in envoy proxy upstreams.
* Store leaf cert indexes in raft and use for the ModifyIndex on the returned certs
This ensures that future certificate signings will have a strictly greater ModifyIndex than any previous certs signed.
## Background
When making a blocking query on a missing service (was never registered, or is not registered anymore) the query returns as soon as any service is updated.
On clusters with frequent updates (5~10 updates/s in our DCs) these queries virtually do not block, and clients with no protections againt this waste ressources on the agent and server side. Clients that do protect against this get updates later than they should because of the backoff time they implement between requests.
## Implementation
While reducing the number of unnecessary updates we still want :
* Clients to be notified as soon as when the last instance of a service disapears.
* Clients to be notified whenever there's there is an update for the service.
* Clients to be notified as soon as the first instance of the requested service is added.
To reduce the number of unnecessary updates we need to block when a request to a missing service is made. However in the following case :
1. Client `client1` makes a query for service `foo`, gets back a node and X-Consul-Index 42
2. `foo` is unregistered
3. `client1` makes a query for `foo` with `index=42` -> `foo` does not exist, the query blocks and `client1` is not notified of the change on `foo`
We could store the last raft index when each service was last alive to know wether we should block on the incoming query or not, but that list could grow indefinetly.
We instead store the last raft index when a service was unregistered and use it when a query targets a service that does not exist.
When a service `srv` is unregistered this "missing service index" is always greater than any X-Consul-Index held by the clients while `srv` was up, allowing us to immediatly notify them.
1. Client `client1` makes a query for service `foo`, gets back a node and `X-Consul-Index: 42`
2. `foo` is unregistered, we set the "missing service index" to 43
3. `client1` makes a blocking query for `foo` with `index=42` -> `foo` does not exist, we check against the "missing service index" and return immediatly with `X-Consul-Index: 43`
4. `client1` makes a blocking query for `foo` with `index=43` -> we block
5. Other changes happen in the cluster, but foo still doesn't exist and "missing service index" hasn't changed, the query is still blocked
6. `foo` is registered again on index 62 -> `foo` exists and its index is greater than 43, we unblock the query
This adds a MaxQueryTime field to the connect ca leaf cache request type and populates it via the wait query param. The cache will then do the right thing and timeout the operation as expected if no new leaf cert is available within that time.
Fixes#4462
The reproduction scenario in the original issue now times out appropriately.
Fixes#4897
Also apparently token deletion could segfault in secondary DCs when attempting to delete non-existant tokens. For that reason both checks are wrapped within the non-nil check.
* Add State storage and LastResult argument into Cache so that cache.Types can safely store additional data that is eventually expired.
* New Leaf cache type working and basic tests passing. TODO: more extensive testing for the Root change jitter across blocking requests, test concurrent fetches for different leaves interact nicely with rootsWatcher.
* Add multi-client and delayed rotation tests.
* Typos and cleanup error handling in roots watch
* Add comment about how the FetchResult can be used and change ca leaf state to use a non-pointer state.
* Plumb test override of root CA jitter through TestAgent so that tests are deterministic again!
* Fix failing config test
* Add default weights when adding a service with no weights to local state to prevent constant AE re-sync.
This fix was contributed by @42wim in https://github.com/hashicorp/consul/pull/5096 but was merged against the wrong base. This adds it to master and adds a test to cover the behaviour.
* Fix tests that broke due to comparing internal state which now has default weights
* Fixes#4480. Don't leave old errors around in cache that can be hit in specific circumstances.
* Move error reset to cover extreme edge case of nil Value, nil err Fetch
* Avoid to have infinite recursion in DNS lookups when resolving CNAMEs
This will avoid killing Consul when a Service.Address is using CNAME
to a Consul CNAME that creates an infinite recursion.
This will fix https://github.com/hashicorp/consul/issues/4907
* Use maxRecursionLevel = 3 to allow several recursions
* bugfix: use ServiceTags to generate cahce key hash
* update unit test
* update
* remote print log
* Update .gitignore
* Completely deprecate ServiceTag field internally for clarity
* Add explicit test for CacheInfo cases
Fixes point `#2` of: https://github.com/hashicorp/consul/issues/4903
When registering a service each healthcheck status is saved and restored (https://github.com/hashicorp/consul/blob/master/agent/agent.go#L1914) to avoid unnecessary flaps in health state.
This change extends this feature to single check registration by moving this protection in `AddCheck()` so that both `PUT /v1/agent/service/register` and `PUT /v1/agent/check/register` behave in the same idempotent way.
#### Steps to reproduce
1. Register a check :
```
curl -X PUT \
http://127.0.0.1:8500/v1/agent/check/register \
-H 'Content-Type: application/json' \
-d '{
"Name": "my_check",
"ServiceID": "srv",
"Interval": "10s",
"Args": ["true"]
}'
```
2. The check will initialize and change to `passing`
3. Run the same request again
4. The check status will quickly go from `critical` to `passing` (the delay for this transission is determined by https://github.com/hashicorp/consul/blob/master/agent/checks/check.go#L95)
This adds the `agent/connect/ca/plugin` library for consuming/serving Connect CA providers as [go-plugin](https://github.com/hashicorp/go-plugin) plugins. This **does not** wire this up in any way to Consul itself, so this will not enable using these plugins yet.
## Why?
We want to enable CA providers to be pluggable without modifying Consul so that any CA or PKI system can potentially back the Connect certificates. This CA system may also be used in the future for easier bootstrapping and internal cluster security.
### go-plugin
The benefit of `go-plugin` is that for the plugin consumer, the fact that the interface implementation is communicating over multi-process RPC is invisible. Internals of Consul will continue to just use `ca.Provider` interface implementations as if they're local. For plugin _authors_, they simply have to implement the interface. The network/transport/process management issues are handled by go-plugin itself.
The CA provider plugins support both `net/rpc` and gRPC transports. This enables easy authoring in any language. go-plugin handles the actual protocol handshake and connection. This is just a feature of go-plugin.
`go-plugin` is already in production use for years by Packer, Terraform, Nomad, Vault, and Sentinel. We've shown stability for both desktop and server-side software. It is very mature.
## Implementation Details
### `map[string]interface{}`
The `Configure` method passes a `map[string]interface{}`. This map contains only Go primitives and containers of primitives (no funcs, chans, etc.). For `net/rpc` we encode as-is using Gob. For gRPC we marshal to JSON and transmit as a `bytes` type. This is the same approach we take with Vault and other software.
Note that this is just the transport protocol, the end software views it fully decoded.
### `x509.Certificate` and `CertificateRequest`
We transmit the raw ASN.1 bytes and decode on the other side. Unit tests are verifying we get the same cert/csrs across the wire.
### Testing
`go-plugin` exposes test helpers that enable testing the full plugin RPC over real loopback network connections. We test all endpoints for success and error for both `net/rpc` and gRPC.
### Vendoring
This PR doesn't introduce vendoring for two reasons:
1. @banks's `f-envoy` branch introduces a lot of these and I didn't want conflict.
2. The library isn't actually used yet so it doesn't introduce compile-time errors (it does introduce test errors).
## Next Steps
With this in place, we need to figure out the proper way to actually hook these up to Consul, load them, etc. This discussion can happen elsewhere, since regardless of approach this plugin library implementation is the exact same.
This endpoint aggregates all checks related to <service id> on the agent
and return an appropriate http code + the string describing the worst
check.
This allows to cleanly expose service status to other component, hiding
complexity of multiple checks.
This is especially useful to use consul to feed a load balancer which
would delegate health checking to consul agent.
Exposing this endpoint on the agent is necessary to avoid a hit on
consul servers and avoid decreasing resiliency (this endpoint will work
even if there is no consul leader in the cluster).
Fixes: https://github.com/hashicorp/consul/issues/3676
This fixes a bug were registering an agent with a non-existent ACL token can prevent other
services registered with a good token from being synced to the server when using
`acl_enforce_version_8 = false`.
## Background
When `acl_enforce_version_8` is off the agent does not check the ACL token validity before
storing the service in its state.
When syncing a service registered with a missing ACL token we fall into the default error
handling case (https://github.com/hashicorp/consul/blob/master/agent/local/state.go#L1255)
and stop the sync (https://github.com/hashicorp/consul/blob/master/agent/local/state.go#L1082)
without setting its Synced property to true like in the permission denied case.
This means that the sync will always stop at the faulty service(s).
The order in which the services are synced is random since we iterate on a map. So eventually
all services with good ACL tokens will be synced, this can however take some time and is influenced
by the cluster size, the bigger the slower because retries are less frequent.
Having a service in this state also prevent all further sync of checks as they are done after
the services.
## Changes
This change modify the sync process to continue even if there is an error.
This fixes the issue described above as well as making the sync more error tolerant: if the server repeatedly refuses
a service (the ACL token could have been deleted by the time the service is synced, the servers
were upgraded to a newer version that has more strict checks on the service definition...).
Then all services and check that can be synced will, and those that don't will be marked as errors in
the logs instead of blocking the whole process.