init

server/plugin/configuration.go

@@ -0,0 +1,75 @@
+package plugin
+
+import (
+	"reflect"
+
+	"github.com/pkg/errors"
+)
+
+type Configuration struct {
+	// Add your configuration fields here
+}
+
+// Clone shallow copies the Configuration. Your implementation may require a deep copy if
+// your Configuration has reference types.
+func (c *Configuration) Clone() *Configuration {
+	var clone = *c
+	return &clone
+}
+
+// GetConfiguration retrieves the active Configuration under lock, making it safe to use
+// concurrently. The active Configuration may change underneath the client of this method, but
+// the struct returned by this API call is considered immutable.
+func (p *Plugin) GetConfiguration() *Configuration {
+	p.configurationLock.RLock()
+	defer p.configurationLock.RUnlock()
+
+	if p.configuration == nil {
+		return &Configuration{}
+	}
+
+	return p.configuration
+}
+
+// SetConfiguration replaces the active Configuration under lock.
+//
+// Do not call SetConfiguration while holding the configurationLock, as sync.Mutex is not
+// reentrant. In particular, avoid using the plugin API entirely, as this may in turn trigger a
+// hook back into the plugin. If that hook attempts to acquire this lock, a deadlock may occur.
+//
+// This method panics if SetConfiguration is called with the existing Configuration. This almost
+// certainly means that the Configuration was modified without being cloned and may result in
+// an unsafe access.
+func (p *Plugin) SetConfiguration(configuration *Configuration) {
+	p.configurationLock.Lock()
+	defer p.configurationLock.Unlock()
+	p.API.LogInfo("Setting configuration")
+
+	if configuration != nil && p.configuration == configuration {
+		// Ignore assignment if the Configuration struct is empty. Go will optimize the
+		// allocation for same to point at the same memory address, breaking the check
+		// above.
+		if reflect.ValueOf(*configuration).NumField() == 0 {
+			return
+		}
+
+		p.API.LogInfo("Panic in SetConfiguration")
+		panic("SetConfiguration called with the existing Configuration")
+	}
+
+	p.configuration = configuration
+}
+
+// OnConfigurationChange is invoked when Configuration changes may have been made.
+func (p *Plugin) OnConfigurationChange() error {
+	p.API.LogInfo("OnConfigurationChange")
+	var configuration = new(Configuration)
+	// Load the public Configuration fields from the Mattermost server Configuration.
+	err := p.API.LoadPluginConfiguration(configuration)
+	if err == nil {
+		p.SetConfiguration(configuration)
+		return nil
+	} else {
+		return errors.Wrap(err, "failed to load plugin Configuration")
+	}
+}