Fix code issues in channel_test.go
Fix Channel Test Issues detected by Megacheck
Fix API Emoji Test Issues detected by Megacheck
Fixed API Issues Reported by Megacheck
Fixed App issues reported by megacheck
Remaining fixes
removed test added by mistake from old HEAD
gofmt
Store Fixes
simplified returns
Fix test for multi member channel delete
revert to delete unused function
* ensure plugin is always shutdown
Once we call `.client.Client()` the plugin has started, and must be shut
down. `newSupervisor` sometimes returned with an error (and without a
reference to the supervisor), leaving the client running indefinitely.
* Clarify the documentation to explain that plugin hooks will not trigger until `OnActivate` returns successfully, and will stop triggering just before `OnDeactivate` is called.
* test for plugin deadlock
* plugin/environment.go: switch to sync.Map
From: https://golang.org/pkg/sync/#Map
> If a goroutine holds a RWMutex for reading and another goroutine might call Lock, no goroutine should expect to be able to acquire a read lock until the initial read lock is released. In particular, this prohibits recursive read locking. This is to ensure that the lock eventually becomes available; a blocked Lock call excludes new readers from acquiring the lock.
The previous `RWMutex` was not safe given that we effectively acquired read locks recursively (hook -> api -> hook). This worked up until we activated or deactivated plugins, tried to acquire a write lock, and the plugin used the API to effectively trigger another hook.
Switching to sync.Map avoids this by divesting the need to lock at all, avoiding the potential for a recursive lock in the first place.
* clean up plugins GoDoc:
- eliminate plugin.NewBlankContext() as unnecessary
- export ValidIdRegex as a string vs. the less readable var
- add/update various documentation strings
- hide everything by default, except where used by client plugins or the mattermost-server. The exception to this rule are the `*(Args|Returns)` structs which must be public for go-plugin, but are now prefixed with `Z_` with a warning not to use.
- include a top-level example to get plugin authors started
This is not a breaking change for existing plugins compiled against
plugins-v2.
* remove commented out ServeHTTPResponseWriter
* update examples to match developer docs
* add missing plugin/doc.go license header
* allow `Wait()`ing on the supervisor
In the event the plugin supervisor shuts down a plugin for crashing too
many times, the new `Wait()` interface allows the `ActivatePlugin` to
accept a callback function to trigger when `supervisor.Wait()` returns.
If the supervisor shuts down normally, this callback is invoked with
a nil error, otherwise any error reported by the supervisor is passed
along.
* improve plugin activation/deactivation logic
Avoid triggering activation of previously failed-to-start plugins just
becase something in the configuration changed. Now, intelligently
compare the global enable bit as well as the each individual plugin's
enabled bit.
* expose store to manipulate PluginStatuses
* expose API to fetch plugin statuses
* keep track of whether or not plugin sandboxing is supported
* transition plugin statuses
* restore error on plugin activation if already active
* don't initialize test plugins until successfully loaded
* emit websocket events when plugin statuses change
* skip pruning if already initialized
* MM-8622: maintain plugin statuses in memory
Switch away from persisting plugin statuses to the database, and
maintain in memory instead. This will be followed by a cluster interface
to query the in-memory status of plugin statuses from all cluster nodes.
At the same time, rename `cluster_discovery_id` on the `PluginStatus`
model object to `cluster_id`.
* MM-8622: aggregate plugin statuses across cluster
* fetch cluster plugin statuses when emitting websocket notification
* address unit test fixes after rebasing
* relax (poor) racey unit test re: supervisor.Wait()
* make store-mocks
* begin backend plugin wip
* flesh out rpcplugin. everything done except for minor supervisor stubs
* done with basic plugin infrastructure
* simplify tests
* remove unused test lines
