Documentation
¶
Overview ¶
Package host implements the plugin hosting functionality.
Index ¶
- Variables
- type AdmissionPlugin
- type Controller
- type Host
- func (h *Host) Close(ctx context.Context)
- func (h *Host) Config() plugin.Config
- func (h *Host) Initialize(cfg plugin.Config) error
- func (h *Host) LaunchPlugin(ctx context.Context, args []string, ctrl *Controller) (*PluginProcess, error)
- func (h *Host) NewAdmissionPlugin(cmdLine []string) (plugin.AdmissionPlugin, error)
- type PluginProcess
- type Promise
Constants ¶
This section is empty.
Variables ¶
var ErrAborted = errors.Reason("the admission plugin is terminating").Err()
ErrAborted is returned by CheckAdmission promise when the plugin terminates.
var ErrTerminated = errors.Reason("terminated with 0 exit code").Err()
ErrTerminated is returned by PluginProcess.Err() if the plugin process exited with 0 exit code.
Functions ¶
This section is empty.
Types ¶
type AdmissionPlugin ¶
type AdmissionPlugin struct {
// contains filtered or unexported fields
}
AdmissionPlugin launches and communicates with an admission plugin.
It is instantiated by the CIPD client if it detects there's an admission plugin configured.
Implements plugin.AdmissionPlugin interface.
func NewAdmissionPlugin ¶
func NewAdmissionPlugin(ctx context.Context, host *Host, args []string) *AdmissionPlugin
NewAdmissionPlugin returns a host-side representation of an admission plugin.
The returned *AdmissionPlugin can be used right away to enqueue admission checks. The plugin subprocess will lazily be started on the first CheckAdmission call. All enqueued checks will eventually be processed by the plugin or rejected if the plugin fails to start.
The context is used for logging from the plugin.
func (*AdmissionPlugin) CheckAdmission ¶
func (p *AdmissionPlugin) CheckAdmission(pin common.Pin) plugin.Promise
CheckAdmission enqueues an admission check to be performed by the plugin.
The plugin will be asked if it's OK to deploy a package with the given pin hosted on the CIPD service used by the running CIPD client.
Returns a promise which is resolved when the result is available. If such check is already pending (or has been done before), returns an existing (perhaps already resolved) promise.
func (*AdmissionPlugin) ClearCache ¶
func (p *AdmissionPlugin) ClearCache()
ClearCache drops all resolved promises to free up some memory.
func (*AdmissionPlugin) Close ¶
func (p *AdmissionPlugin) Close(ctx context.Context)
Close terminates the plugin (if it was running) and aborts all pending checks.
Tries to gracefully terminate the plugin, killing it with SIGKILL on the context timeout or after 5 sec.
Note that calling Close is not necessary if the plugin host itself terminates. The plugin subprocess will be terminated by the host in this case.
func (*AdmissionPlugin) Executable ¶
func (p *AdmissionPlugin) Executable() string
Executable is a path to this plugin's executable.
type Controller ¶
type Controller struct {
Admissions protocol.AdmissionsServer // non-nil for deployment admission plugins
}
Controller lives in the host process and manages communication with a plugin.
Each instance of a plugin has a Controller associated with it. The controller exposes a subset of gRPC services that the particular plugin is allowed to call. That way it's possible to have different kinds of plugins by exposing different services to them.
type Host ¶
type Host struct {
// PluginsContext is used for asynchronous logging from plugins.
PluginsContext context.Context
// contains filtered or unexported fields
}
Host launches plugin subprocesses and accepts connections from them.
Implements plugin.Host interface.
func (*Host) Close ¶
Close terminates all plugins and releases all resources.
Waits for the plugins to terminate gracefully. On context deadline kills them with SIGKILL.
It is a part of plugin.Host interface.
func (*Host) Initialize ¶
Initialize is called when the CIPD client starts before any other call.
It is a part of plugin.Host interface.
func (*Host) LaunchPlugin ¶
func (h *Host) LaunchPlugin(ctx context.Context, args []string, ctrl *Controller) (*PluginProcess, error)
LaunchPlugin launches a plugin subprocesses.
Does not wait for it to connect. Returns a handle that can be used to control the process.
Uses the given context for logging from the plugin.
func (*Host) NewAdmissionPlugin ¶
func (h *Host) NewAdmissionPlugin(cmdLine []string) (plugin.AdmissionPlugin, error)
NewAdmissionPlugin returns a handle to an admission plugin.
It is a part of plugin.Host interface.
type PluginProcess ¶
type PluginProcess struct {
// contains filtered or unexported fields
}
PluginProcess represents a plugin subprocess.
func (*PluginProcess) Done ¶
func (p *PluginProcess) Done() <-chan struct{}
Done returns a channel that closes when the plugin terminates.
func (*PluginProcess) Err ¶
func (p *PluginProcess) Err() error
Err returns an error if the plugin terminated (gracefully or not).
Valid only if Done() is already closed, nil otherwise.
func (*PluginProcess) Terminate ¶
func (p *PluginProcess) Terminate(ctx context.Context) error
Terminate tries to gracefully terminate the plugin process, killing it with SIGKILL on the context expiration or after 5 sec.
Returns the same value as Err(). Does nothing if the process is already terminated.
Source Files