Whenever an upsert/deletion of a config entry happens, within the open
state store transaction we speculatively test compile all discovery
chains that may be affected by the pending modification to verify that
the write would not create an erroneous scenario (such as splitting
traffic to a subset that did not exist).
If a single discovery chain evaluation references two config entries
with the same kind and name in different namespaces then sometimes the
upsert/deletion would be falsely rejected. It does not appear as though
this bug would've let invalid writes through to the state store so the
correction does not require a cleanup phase.
This commit refactors the state store usage code to track unique service
name changes on transaction commit. This means we only need to lookup
usage entries when reading the information, as opposed to iterating over
a large number of service indices.
- Take into account a service instance's name being changed
- Do not iterate through entire list of service instances, we only care
about whether there is 0, 1, or more than 1.
We add a WriteTxn interface for use in updating the usage memdb table,
with the forward-looking prospect of incrementally converting other
functions to accept interfaces.
As well, we use the ReadTxn in new usage code, and as a side effect
convert a couple of existing functions to use that interface as well.
Using the newly provided state store methods, we periodically emit usage
metrics from the servers.
We decided to emit these metrics from all servers, not just the leader,
because that means we do not have to care about leader election flapping
causing metrics turbulence, and it seems reasonable for each server to
emit its own view of the state, even if they should always converge
rapidly.
And into token.Store. This change isolates any awareness of token
persistence in a single place.
It is a small step in allowing Agent.New to accept its dependencies.
This test was only passing because t.Parallel was causing every subtest to run with the last value in the iteration,
which sets a value for all tokens. The test started to fail once t.Parallel was removed, but the same failure could
have been produced by adding 'tt := tt' to the t.Run() func.
These tests run in under 10ms, so there is no reason to use t.Parallel.
This will apply cache throttling parameters are properly applied:
* cache.EntryFetchMaxBurst
* cache.EntryFetchRate
When values are updated, a log is displayed in info.
This might be better handled by allowing configuration for the InMemSink interval and retail, and disabling
the global. For now this is a smaller change to remove the goroutine leak caused by tests because go-metrics
does not provide any way of shutting down the global goroutine.
With this change, Agent.New() accepts many of the dependencies instead
of creating them in New. Accepting fully constructed dependencies from
a constructor makes the type easier to test, and easier to change.
There are still a number of dependencies created in Start() which can
be addressed in a follow up.
During gossip encryption key rotation it would be nice to be able to see if all nodes are using the same key. This PR adds another field to the json response from `GET v1/operator/keyring` which lists the primary keys in use per dc. That way an operator can tell when a key was successfully setup as primary key.
Based on https://github.com/hashicorp/serf/pull/611 to add primary key to list keyring output:
```json
[
{
"WAN": true,
"Datacenter": "dc2",
"Segment": "",
"Keys": {
"0OuM4oC3Os18OblWiBbZUaHA7Hk+tNs/6nhNYtaNduM=": 6,
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 6
},
"PrimaryKeys": {
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 6
},
"NumNodes": 6
},
{
"WAN": false,
"Datacenter": "dc2",
"Segment": "",
"Keys": {
"0OuM4oC3Os18OblWiBbZUaHA7Hk+tNs/6nhNYtaNduM=": 8,
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 8
},
"PrimaryKeys": {
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 8
},
"NumNodes": 8
},
{
"WAN": false,
"Datacenter": "dc1",
"Segment": "",
"Keys": {
"0OuM4oC3Os18OblWiBbZUaHA7Hk+tNs/6nhNYtaNduM=": 3,
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 8
},
"PrimaryKeys": {
"SINm887hKTzmMWeBNKTJReaTLX3mBEJKriDyt88Ad+g=": 8
},
"NumNodes": 8
}
]
```
I intentionally did not change the CLI output because I didn't find a good way of displaying this information. There are a couple of options that we could implement later:
* add a flag to show the primary keys
* add a flag to show json output
Fixes#3393.
Previsouly it was done in Agent.Start, which is much later then it needs to be.
The new 'dns' package was required, because otherwise there would be an
import cycle. In the future we should move more of the dns server into
the dns package.
- unexport testing shims, and document their purpose
- resolve a TODO by moving validation to NewBuilder and storing the one
field that is used instead of all of Options
- create a slice with the correct size to avoid extra allocations
While working on another change I caused a bunch of these tests to fail.
Unfortunately the failure messages were not super helpful at first.
One problem was that the request and response were created outside of
the retry. This meant that when the second attempt happened, the request
body was empty (because the buffer had been consumed), and so the
request was not actually being retried. This was fixed by moving more of
the request creation into the retry block.
Another problem was that these functions can return errors in two ways, and
are not consistent about which way they use. Some errors are returned to
the response writer, but the tests were not checking those errors, which
was causing a panic later on. This was fixed by adding a check for the
response code.
Also adds some missing t.Helper(), and has assertIndex use checkIndex so
that it is clear these are the same implementation.
I saw this test flake locally, and it was easy to reproduce with -count=10.
The failure was: 'TestAgent.dns: rpc error: error=No known Consul servers'.
Waiting for the agent seems to fix it.
This commit fixes a test that I saw flake locally while running tests. The test output from the monitor
started immediately after the line the test was looking for.
To fix the problem a channel is closed when the goroutine starts. Shutdown is not called until this channel
is closed, which seems to greatly reduce the chance of a flake.
TestAgent.Key was only used by 3 tests. Extracting it from the common helper that is used in hundreds of
tests helps keep the shared part small and more focused.
This required a second change (which I was planning on making anyway), which was to change the behaviour of
DataDir. Now in all cases the TestAgent will use the DataDir, and clean it up once the test is complete.
There are a couple reasons for this change:
1. agent.go is way too big. Smaller files makes code eaasier to read
because tools that show usage also include filename which can give
a lot more context to someone trying to understand which functions
call other functions.
2. these two functions call into a large number of functions already in
keyring.go.
This is a small step to allowing Agent to accept its dependencies
instead of creating them in New.
There were two fields in autoconfig.Config that were used exclusively
to load config. These were replaced with a single function, allowing us
to move LoadConfig back to the config package.
Also removed the WithX functions for building a Config. Since these were
simple assignment, it appeared we were not getting much value from them.
Making these functions allows us to cleanup how an agent is initialized. They only make use of a config and a logger, so they do not need to be agent methods.
Also cleanup the testing to use t.Run and require.
Fixes#8466
Since Consul 1.8.0 there was a bug in how ingress gateway protocol
compatibility was enforced. At the point in time that an ingress-gateway
config entry was modified the discovery chain for each upstream was
checked to ensure the ingress gateway protocol matched. Unfortunately
future modifications of other config entries were not validated against
existing ingress-gateway definitions, such as:
1. create tcp ingress-gateway pointing to 'api' (ok)
2. create service-defaults for 'api' setting protocol=http (worked, but not ok)
3. create service-splitter or service-router for 'api' (worked, but caused an agent panic)
If you were to do these in a different order, it would fail without a
crash:
1. create service-defaults for 'api' setting protocol=http (ok)
2. create service-splitter or service-router for 'api' (ok)
3. create tcp ingress-gateway pointing to 'api' (fail with message about
protocol mismatch)
This PR introduces the missing validation. The two new behaviors are:
1. create tcp ingress-gateway pointing to 'api' (ok)
2. (NEW) create service-defaults for 'api' setting protocol=http ("ok" for back compat)
3. (NEW) create service-splitter or service-router for 'api' (fail with
message about protocol mismatch)
In consideration for any existing users that may be inadvertently be
falling into item (2) above, that is now officiall a valid configuration
to be in. For anyone falling into item (3) above while you cannot use
the API to manufacture that scenario anymore, anyone that has old (now
bad) data will still be able to have the agent use them just enough to
generate a new agent/proxycfg error message rather than a panic.
Unfortunately we just don't have enough information to properly fix the
config entries.
* changes some functions to return data instead of modifying pointer
arguments
* renames globalRPC() to keyringRPCs() to make its purpose more clear
* restructures KeyringOperation() to make it more understandable
* update bindata_assetfs.go
* Release v1.8.2
* Putting source back into Dev Mode
* changelog: add entries for 1.7.6, 1.7.5 and 1.6.7
Co-authored-by: hashicorp-ci <hashicorp-ci@users.noreply.github.com>
NotifyShutdown was only used for testing. Now that t.Cleanup exists, we
can use that instead of attaching cleanup to the Server shutdown.
The Autopilot test which used NotifyShutdown doesn't need this
notification because Shutdown is synchronous. Waiting for the function
to return is equivalent.
AutoConfig will generate local tokens for clients and the ability to use local tokens is gated off of token replication being enabled and being configured with a replication token. Therefore we already have a hard requirement on having token replication enabled, this commit just makes sure to surface that to the operator instead of having to discern what the issue is from RPC errors.
This code started as an optimization to avoid doing an RPC Ping to
itself. But in a single server cluster the rebalancing was led to
believe that there were no healthy servers because foundHealthyServer
was not set. Now this is being set properly.
Fixes#8401 and #8403.
Now that it is no longer used, we can remove this unnecessary field. This is a pre-step in cleanup up RuntimeConfig->Consul.Config, which is a pre-step to adding a gRPCHandler component to Server for streaming.
Removing this field also allows us to remove one of the return values from logging.Setup.
The main bug was fixed in cb050b280c, but the return value of 'result' is still misleading.
Change the return value to nil to make the code more clear.
Related changes:
- hard-fail the xDS connection attempt if the envoy version is known to be too old to be supported
- remove the RouterMatchSafeRegex proxy feature since all supported envoy versions have it
- stop using --max-obj-name-len (due to: envoyproxy/envoy#11740)
Ensure that enabling AutoConfig sets the tls configurator properly
This also refactors the TLS configurator a bit so the naming doesn’t imply only AutoEncrypt as the source of the automatically setup TLS cert info.
Most of the groundwork was laid in previous PRs between adding the cert-monitor package to extracting the logic of signing certificates out of the connect_ca_endpoint.go code and into a method on the server.
This also refactors the auto-config package a bit to split things out into multiple files.
There were several PRs that while all passed CI independently, when they all got merged into the same branch caused compilation errors in test code.
The main changes that caused issues where changing agent/cache.Cache.New to require a concrete options struct instead of a pointer. This broke the cert monitor tests and the catalog_list_services_test.go. Another change was made to unembed the http.Server from the agent.HTTPServer struct. That coupled with another change to add a test to ensure cache rate limiting coming from HTTP requests was working as expected caused compilation failures.
This implements a solution for #7863
It does:
Add a new config cache.entry_fetch_rate to limit the number of calls/s for a given cache entry, default value = rate.Inf
Add cache.entry_fetch_max_burst size of rate limit (default value = 2)
The new configuration now supports the following syntax for instance to allow 1 query every 3s:
command line HCL: -hcl 'cache = { entry_fetch_rate = 0.333}'
in JSON
{
"cache": {
"entry_fetch_rate": 0.333
}
}
Replaces #7559
Running tests in parallel, with background goroutines, results in test output not being associated with the correct test. `go test` does not make any guarantees about output from goroutines being attributed to the correct test case.
Attaching log output from background goroutines also cause data races. If the goroutine outlives the test, it will race with the test being marked done. Previously this was noticed as a panic when logging, but with the race detector enabled it is shown as a data race.
The previous solution did not address the problem of correct test attribution because test output could still be hidden when it was associated with a test that did not fail. You would have to look at all of the log output to find the relevant lines. It also made debugging test failures more difficult because each log line was very long.
This commit attempts a new approach. Instead of printing all the logs, only print when a test fails. This should work well when there are a small number of failures, but may not work well when there are many test failures at the same time. In those cases the failures are unlikely a result of a specific test, and the log output is likely less useful.
All of the logs are printed from the test goroutine, so they should be associated with the correct test.
Also removes some test helpers that were not used, or only had a single caller. Packages which expose many functions with similar names can be difficult to use correctly.
Related:
https://github.com/golang/go/issues/38458 (may be fixed in go1.15)
https://github.com/golang/go/issues/38382#issuecomment-612940030
The rationale behind removing them is that all of our own code (xDS, builtin connect proxy) use the cache notification mechanism. This ensures that the blocking fetch behind the scenes is always executing. Therefore the only way you might go to get a certificate and have to wait is when 1) the request has never been made for that cert before or 2) you are using the v1/agent/connect/ca/leaf API for retrieving the cert yourself.
In the first case, the refresh change doesn’t alter the behavior. In the second case, it can be mitigated by using blocking queries with that API which just like normal cache notification mechanism will cause the blocking fetch to be initiated and to get leaf certs as soon as needed.
If you are not using blocking queries, or Envoy/xDS, or the builtin connect proxy but are retrieving the certs yourself then the HTTP endpoint might take a little longer to respond.
This also renames the RefreshTimeout field on the register options to QueryTimeout to more accurately reflect that it is used for any type that supports blocking queries.
The fallback method would still work but it would get into a state where it would let the certificate expire for 10s before getting a new one. And the new one used the less secure RPC endpoint.
This is also a pretty large refactoring of the auto encrypt code. I was going to write some tests around the certificate monitoring but it was going to be impossible to get a TestAgent configured in such a way that I could write a test that ran in less than an hour or two to exercise the functionality.
Moving the certificate monitoring into its own package will allow for dependency injection and in particular mocking the cache types to control how it hands back certificates and how long those certificates should live. This will allow for exercising the main loop more than would be possible with it coupled so tightly with the Agent.
CheckAlias already had a waitGroup, but the Add() call was happening too late, which was causing a race in tests. The add must happen before the goroutine is started.
CheckHTTP did not have a waitGroup, so I added it to match CheckAlias.
It looks like a lot of the implementation could be shared, and may not need all of channel, waitgroup and bool, but I will leave that refactor for another time.
When the race detector is enabled we see this test fail occasionally. The reordering of execution seems to make it possible for the snapshot splice to happen before any events are published to the topicBuffers.
We can handle this case in the test the same way it is handled by a subscription, by proceeding to the next event.
This change was mostly automated with the following
First generate a list of functions with:
git grep -o 'Store) \([^(]\+\)(tx \*txn' ./agent/consul/state | awk '{print $2}' | grep -o '^[^(]\+'
Then the list was curated a bit with trial/error to remove and add funcs
as necessary.
Finally the replacement was done with:
dir=agent/consul/state
file=${1-funcnames}
while read fn; do
echo "$fn"
sed -i -e "s/(s \*Store) $fn(/$fn(/" $dir/*.go
sed -i -e "s/s\.$fn(/$fn(/" $dir/*.go
sed -i -e "s/s\.store\.$fn(/$fn(/" $dir/*.go
done < $file
Making these functions allows them to be used without introducing
an artificial dependency on the struct. Many of these will be called
from streaming Event processors, which do not have a store.
This change is being made ahead of the streaming work to get to reduce
the size of the streaming diff.
Move the subscription context to Next. context.Context should generally
never be stored in a struct because it makes that struct only valid
while the context is valid. This is rarely obvious from the caller.
Adds a forceClosed channel in place of the old context, and uses the new
context as a way for the caller to stop the Subscription blocking.
Remove some recursion out of bufferImte.Next. The caller is already looping so we can continue
in that loop instead of recursing. This ensures currentItem is updated immediately (which probably
does not matter in practice), and also removes the chance that we overflow the stack.
NextNoBlock and FollowAfter do not need to handle bufferItem.Err, the caller already
handles it.
Moves filter to a method to simplify Next, and more explicitly separate filtering from looping.
Also improve some godoc
Only unwrap itemBuffer.Err when necessary
EventPublisher was receiving TopicHandlers, which had a couple of
problems:
- ChangeProcessors were being grouped by Topic, but they completely
ignored the topic and were performed on every change
- ChangeProcessors required EventPublisher to be aware of database
changes
By moving ChangeProcesors out of EventPublisher, and having Publish
accept events instead of changes, EventPublisher no longer needs to
be aware of these things.
Handlers is now only SnapshotHandlers, which are still mapped by Topic.
Also allows us to remove the small 'db' package that had only two types.
They can now be unexported types in state.
The EventPublisher is the central hub of the PubSub system. It is toughly coupled with much of
stream. Some stream internals were exported exclusively for EventPublisher.
The two Subscribe cases (with or without index) were also awkwardly split between two packages. By
moving EventPublisher into stream they are now both in the same package (although still in different files).
Also store the index in Changes instead of the Txn.
This change is in preparation for movinng EventPublisher to the stream package, and
making handleACLUpdates async once again.
It is critical that Unsubscribe be called with the same pointer to a
SubscriptionRequest that was used to create the Subscription. The
docstring made that clear, but it sill allowed a caler to get it wrong by
creating a new SubscriptionRequest.
By hiding this detail from the caller, and only exposing an Unsubscribe
method, it should be impossible to fail to Unsubscribe.
Also update some godoc strings.
Use a separate lock for subscriptions.ByToken to allow it to happen synchronously
in the commit flow.
This removes the need to create a new txn for the goroutine, and removes
the need for EventPublisher to contain a reference to DB.
Many of the fields are only needed in one place, and by using a closure
they can be removed from the struct. This reduces the scope of the variables
making it esier to see how they are used.
Otherwise the test will run with exactly the same values each time.
By printing the seed we can attempt to reproduce the test by adding an env var to override the seed
Make topicRegistry use functions instead of unbound methods
Use a regular memDB in EventPublisher to remove a reference cycle
Removes the need for EventPublisher to use a store
Also remove secretHash, which was used to hash tokens. We don't expose
these tokens anywhere, so we can use the string itself instead of a
Hash.
Fix acl_events_test.go for storing a structs type.
This is instead of having the AutoConfigBackend interface provide functions for retrieving them.
NOTE: the config is not reloadable. For now this is fine as we don’t look at any reloadable fields. If that changes then we should provide a way to make it reloadable.
A port can be sent in the Host header as defined in the HTTP RFC, so we
take any hosts that we want to match traffic to and also add another
host with the listener port added.
Also fix an issue with envoy integration tests not running the
case-ingress-gateway-tls test.
In all cases (oss/ent, client/server) this method was returning a value from config. Since the
value is consistent, it doesn't need to be part of the delegate interface.
Fixes#7527
I want to highlight this and explain what I think the implications are and make sure we are aware:
* `HTTPConnStateFunc` closes the connection when it is beyond the limit. `Close` does not block.
* `HTTPConnStateFuncWithDefault429Handler(10 * time.Millisecond)` blocks until the following is done (worst case):
1) `conn.SetDeadline(10*time.Millisecond)` so that
2) `conn.Write(429error)` is guaranteed to timeout after 10ms, so that the http 429 can be written and
3) `conn.Close` can happen
The implication of this change is that accepting any new connection is worst case delayed by 10ms. But only after a client reached the limit already.
The embedded HTTPServer struct is not used by the large HTTPServer
struct. It is used by tests and the agent. This change is a small first
step in the process of removing that field.
The eventual goal is to reduce the scope of HTTPServer making it easier
to test, and split into separate packages.
A query made with AllowNotModifiedResponse and a MinIndex, where the
result has the same Index as MinIndex, will return an empty response
with QueryMeta.NotModified set to true.
Co-authored-by: Pierre Souchay <pierresouchay@users.noreply.github.com>
Also fix a bug where Consul could segfault if TLS was enabled but no client certificate was provided. How no one has reported this as a problem I am not sure.
The initial auto encrypt CSR wasn’t containing the user supplied IP and DNS SANs. This fixes that. Also We were configuring a default :: IP SAN. This should be ::1 instead and was fixed.
Highlights:
- add new endpoint to query for intentions by exact match
- using this endpoint from the CLI instead of the dump+filter approach
- enforcing that OSS can only read/write intentions with a SourceNS or
DestinationNS field of "default".
- preexisting OSS intentions with now-invalid namespace fields will
delete those intentions on initial election or for wildcard namespaces
an attempt will be made to downgrade them to "default" unless one
exists.
- also allow the '-namespace' CLI arg on all of the intention subcommands
- update lots of docs
Split up unused key validation in config entry decode for oss/ent.
This is needed so that we can return an informative error in OSS if namespaces are provided.
Previously, we were only returning a single ListenerPort for a single
service. However, we actually allow a single service to be serviced over
multiple ports, as well as allow users to define what hostnames they
expect their services to be contacted over. When no hosts are defined,
we return the default ingress domain for any configured DNS domain.
To show this in the UI, we modify the gateway-services-nodes API to
return a GatewayConfig.Addresses field, which is a list of addresses
over which the specific service can be contacted.
This is in its own separate package so that it will be a separate test binary that runs thus isolating the go runtime from other tests and allowing accurate go routine leak checking.
This test would ideally use goleak.VerifyTestMain but that will fail 100% of the time due to some architectural things (blocking queries and net/rpc uncancellability).
This test is not comprehensive. We should enable/exercise more features and more cluster configurations. However its a start.
The old test case was a very specific regresion test for a case that is no longer possible.
Replaced with a new test that checks the default coordinate is returned.
We needed to pass a cancellable context into the limiter.Wait instead of context.Background. So I made the func take a context instead of a chan as most places were just passing through a Done chan from a context anyways.
Fix go routine leak in the gateway locator
This will allow to increase cache value when DC is not valid (aka
return SOA to avoid too many consecutive requests) and will
distinguish DC being temporarily not available from DC not existing.
Implements https://github.com/hashicorp/consul/issues/8102
On the servers they must have a certificate.
On the clients they just have to set verify_outgoing to true to attempt TLS connections for RPCs.
Eventually we may relax these restrictions but right now all of the settings we push down (acl tokens, acl related settings, certificates, gossip key) are sensitive and shouldn’t be transmitted over an unencrypted connection. Our guides and docs should recoommend verify_server_hostname on the clients as well.
Another reason to do this is weird things happen when making an insecure RPC when TLS is not enabled. Basically it tries TLS anyways. We should probably fix that to make it clearer what is going on.
The envisioned changes would allow extra settings to enable dynamically defined auth methods to be used instead of or in addition to the statically defined one in the configuration.
There are a couple of things in here.
First, just like auto encrypt, any Cluster.AutoConfig RPC will implicitly use the less secure RPC mechanism.
This drastically modifies how the Consul Agent starts up and moves most of the responsibilities (other than signal handling) from the cli command and into the Agent.
All commands which read config (agent, services, and validate) will now
print warnings when one of the config files is skipped because it did
not match an expected format.
Also ensures that config validate prints all warnings.
Right now this is only hooked into the insecure RPC server and requires JWT authorization. If no JWT authorizer is setup in the configuration then we inject a disabled “authorizer” to always report that JWT authorization is disabled.
While upgrading servers to a new version, I saw that metadata of
existing servers are not upgraded, so the version and raft meta
is not up to date in catalog.
The only way to do it was to:
* update Consul server
* make it leave the cluster, then metadata is accurate
That's because the optimization to avoid updating catalog does
not take into account metadata, so no update on catalog is performed.
And fix the 'value not used' issues.
Many of these are not bugs, but a few are tests not checking errors, and
one appears to be a missed error in non-test code.
A Node Identity is very similar to a service identity. Its main targeted use is to allow creating tokens for use by Consul agents that will grant the necessary permissions for all the typical agent operations (node registration, coordinate updates, anti-entropy).
Half of this commit is for golden file based tests of the acl token and role cli output. Another big updates was to refactor many of the tests in agent/consul/acl_endpoint_test.go to use the same style of tests and the same helpers. Besides being less boiler plate in the tests it also uses a common way of starting a test server with ACLs that should operate without any warnings regarding deprecated non-uuid master tokens etc.
Previously the logic for reading ConfigFiles and produces Sources was split
between NewBuilder and Build. This commit moves all of the logic into NewBuilder
so that Build() can operate entirely on Sources.
This change is in preparation for logging warnings when files have an
unsupported extension.
It also reduces the scope of BuilderOpts, and gets us very close to removing
Builder.options.
The nil value was never used. We can avoid a bunch of complications by
making the field a string value instead of a pointer.
This change is in preparation for fixing a silent config failure.
Flags is an overloaded term in this context. It generally is used to
refer to command line flags. This struct, however, is a data object
used as input to the construction.
It happens to be partially populated by command line flags, but
otherwise has very little to do with them.
Renaming this struct should make the actual responsibility of this struct
more obvious, and remove the possibility that it is confused with
command line flags.
This change is in preparation for adding additional fields to
BuilderOpts.
This field was populated for one reason, to test that it was empty.
Of all the callers, only a single one used this functionality. The rest
constructed a `Flags{}` struct which did not set Args.
I think this shows that the logic was in the wrong place. Only the agent
command needs to care about validating the args.
This commit removes the field, and moves the logic to the one caller
that cares.
Also fix some comments.
Passing the channel to the function which uses it significantly
reduces the scope of the variable, and makes its usage more explicit. It
also moves the initialization of the channel closer to where it is used.
Also includes a couple very small cleanups to remove a local var and
read the error from `ctx.Err()` directly instead of creating a channel
to check for an error.
This field was always read by the same function that populated the field,
so it does not need to be a field. Passing the value as an argument to
functions makes it more obvious where the value comes from, and also reduces
the scope of the variable significantly.
[The documentation for context](https://golang.org/pkg/context/)
recommends not storing context in a struct field:
> Do not store Contexts inside a struct type; instead, pass a Context
> explicitly to each function that needs it. The Context should be the
> first parameter, typically named ctx...
Sometimes there are good reasons to not follow this recommendation, but
in this case it seems easy enough to follow.
Also moved the ctx argument to be the first in one of the function calls
to follow the same recommendation.
freddygv
R.B. Boyer
Chris Piraino
Daniel Nephin
Matt Keeler
Pierre Souchay
Jack
Kyle Havlovitz
André Cruz
Hans Hasselberg
Freddy
Mike Morris
Matt Keeler
Pierre Souchay
Paul Coignet
André
Yury Evtikhov
gitforbit
Paul Banks