This turns out to have a lot more subtelty than we accounted for. The test suite is especially prone to races now we can only poll the child and many extra levels of indirectoin are needed to correctly run daemon process without it becoming a Zombie.
I ran this test suite in a loop with parallel enabled to verify for races (-race doesn't find any as they are logical inter-process ones not actual data races). I made it through ~50 runs before hitting an error due to timing which is much better than before. I want to go back and see if we can do better though. Just getting this up.
Uses struct/interface embedding with the embedded structs/interfaces being empty for oss. Also methods on the server/client types are defaulted to do nothing for OSS
Previously a change was made to make the file writing atomic,
but that wasn't enough to cover something like an OS crash so we
needed something here to handle the situation more gracefully.
Fixes#1221.
Since commit 9685bdcd0b, service tags are added to the health checks.
Otherwise, when adding a service, tags are not added to its check.
In updateSyncState, we compare the checks of the local agent with the checks of the catalog.
It appears that the service tags are different (missing in one case), and so the check is synchronized.
That increase the ModifyIndex periodically when nothing changes.
Fixed it by adding serviceTags to the check.
Note that the issue appeared in version 0.8.2.
Looks related to #3259.
* Refactors the HTTP listen path to create servers in the same spot.
* Adds HTTP/2 support to Consul's HTTPS server.
* Vendors Go HTTP/2 library and associated deps.
The state of the service and health check records was spread out over
multiple maps guarded by a single lock. Access to the maps has to happen
in a coordinated effort and the tests often violated this which made
them brittle and racy.
This patch replaces the multiple maps with a single one for both checks
and services to make the code less fragile.
This is also necessary since moving the local state into its own package
creates circular dependencies for the tests. To avoid this the tests can
no longer access internal data structures which they should not be doing
in the first place.
The tests still don't compile but this is a ncessary step in that
direction.
The anti-entropy code manages background synchronizations of the local
state on a regular basis or on demand when either the state has changed
or a new consul server has been added.
This patch moves the anti-entropy code into its own package and
decouples it from the local state code since they are performing
two different functions.
To simplify code-review this revision does not make any optimizations,
renames or refactorings. This will happen in subsequent commits.
The state of the service and health check records was spread out over
multiple maps guarded by a single lock. Access to the maps has to happen
in a coordinated effort and the tests often violated this which made
them brittle and racy.
This patch replaces the multiple maps with a single one for both checks
and services to make the code less fragile.
This is also necessary since moving the local state into its own package
creates circular dependencies for the tests. To avoid this the tests can
no longer access internal data structures which they should not be doing
in the first place.
The tests still don't compile but this is a ncessary step in that
direction.
The anti-entropy code manages background synchronizations of the local
state on a regular basis or on demand when either the state has changed
or a new consul server has been added.
This patch moves the anti-entropy code into its own package and
decouples it from the local state code since they are performing
two different functions.
To simplify code-review this revision does not make any optimizations,
renames or refactorings. This will happen in subsequent commits.
* agent: add option to discard health output
In high volatile environments consul will have checks with "noisy"
output which changes every time even though the status does not change.
Since the output is stored in the raft log every health check update
unblocks a blocking call on health checks since the raft index has
changed even though the status of the health checks may not have changed
at all. By discarding the output of the health checks the users can
choose a different tradeoff. Less visibility on why a check failed in
exchange for a reduced change rate on the raft log.
* agent: discard output also when adding a check
* agent: add test for discard check output
* agent: update docs
* go vet
* Adds discard_check_output to reloadable config table.
* Updates the change log.
* Fixes agent error handling when check definition is invalid. Distinguishes between empty checks vs invalid checks
* Made CheckTypes return Checks from service definition struct rather than a new copy, and other changes from code review. This also errors when json payload contains empty structs
* Simplify and improve validate method, and make sure that CheckTypes always returns a new copy of validated check definitions
* Tweaks some small style things and error messages.
* Updates the change log.
* Adds client-side retry for no leader errors.
This paves over the case where the client was connected to the leader
when it loses leadership.
* Adds a configurable server RPC drain time and a fail-fast path for RPCs.
When a server leaves it gets removed from the Raft configuration, so it will
never know who the new leader server ends up being. Without this we'd be
doomed to wait out the RPC hold timeout and then fail. This makes things fail
a little quicker while a sever is draining, and since we added a client retry
AND since the server doing this has already shut down and left the Serf LAN,
clients should retry against some other server.
* Makes the RPC hold timeout configurable.
* Reorders struct members.
* Sets the RPC hold timeout default for test servers.
* Bumps the leave drain time up to 5 seconds.
* Robustifies retries with a simpler client-side RPC hold.
* Reverts untended delete.