feat(http): expose list of available telegraf plugins (#16233)

http/api_handler.go

@@ -184,6 +184,7 @@ func NewAPIHandler(b *APIBackend, opts ...APIHandlerOptFn) *APIHandler {
 
 	telegrafBackend := NewTelegrafBackend(b.Logger.With(zap.String("handler", "telegraf")), b)
 	telegrafBackend.TelegrafService = authorizer.NewTelegrafConfigService(b.TelegrafService, b.UserResourceMappingService)
+	h.Mount(prefixTelegrafPlugins, NewTelegrafHandler(b.Logger, telegrafBackend))
 	h.Mount(prefixTelegraf, NewTelegrafHandler(b.Logger, telegrafBackend))
 
 	userBackend := NewUserBackend(b.Logger.With(zap.String("handler", "user")), b)
@@ -241,6 +242,7 @@ var apiLinks = map[string]interface{}{
 	"tasks":     "/api/v2/tasks",
 	"checks":    "/api/v2/checks",
 	"telegrafs": "/api/v2/telegrafs",
+	"plugins":   "/api/v2/telegraf/plugins",
 	"users":     "/api/v2/users",
 	"write":     "/api/v2/write",
 	"delete":    "/api/v2/delete",

http/swagger.yml

@@ -339,6 +339,29 @@ paths:
             application/json:
               schema:
                 $ref: "#/components/schemas/Error"
+  /telegraf/plugins:
+    get:
+      operationId: GetTelegrafPlugins
+      parameters:
+          - $ref: '#/components/parameters/TraceSpan'
+          - in: query
+            name: type
+            description: The type of plugin desired.
+            schema:
+              type: string
+      responses:
+        '200':
+          description: A list of Telegraf plugins.
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/TelegrafPlugins"
+        default:
+          description: Unexpected error
+          content:
+            application/json:
+              schema:
+                $ref: "#/components/schemas/Error"
   /telegrafs:
     get:
       operationId: GetTelegrafs
@@ -9635,6 +9658,28 @@ components:
           type: array
           items:
             $ref: "#/components/schemas/Telegraf"
+    TelegrafPlugin:
+      type: object
+      properties:
+        type:
+          type: string
+        name:
+          type: string
+        description:
+          type: string
+        config:
+          type: string
+    TelegrafPlugins:
+      type: object
+      properties:
+        version:
+          type: string
+        os:
+          type: string
+        plugins:
+          type: array
+          items:
+            $ref: "#/components/schemas/TelegrafPlugin"
     TelegrafPluginInputDockerConfig:
       type: object
       required:

http/telegraf.go

@@ -65,6 +65,9 @@ const (
 	telegrafsIDOwnersIDPath  = "/api/v2/telegrafs/:id/owners/:userID"
 	telegrafsIDLabelsPath    = "/api/v2/telegrafs/:id/labels"
 	telegrafsIDLabelsIDPath  = "/api/v2/telegrafs/:id/labels/:lid"
+
+	prefixTelegrafPlugins = "/api/v2/telegraf"
+	telegrafPluginsPath   = "/api/v2/telegraf/plugins"
 )
 
 // NewTelegrafHandler returns a new instance of TelegrafHandler.
@@ -86,6 +89,8 @@ func NewTelegrafHandler(log *zap.Logger, b *TelegrafBackend) *TelegrafHandler {
 	h.HandlerFunc("DELETE", telegrafsIDPath, h.handleDeleteTelegraf)
 	h.HandlerFunc("PUT", telegrafsIDPath, h.handlePutTelegraf)
 
+	h.HandlerFunc("GET", telegrafPluginsPath, h.handleGetTelegrafPlugins)
+
 	memberBackend := MemberBackend{
 		HTTPErrorHandler:           b.HTTPErrorHandler,
 		log:                        b.log.With(zap.String("handler", "member")),
@@ -189,6 +194,29 @@ type telegrafResponses struct {
 	TelegrafConfigs []*telegrafResponse `json:"configurations"`
 }
 
+func getTelegrafPlugins(t string) (*plugins.TelegrafPlugins, error) {
+	if len(t) == 0 {
+		return plugins.AvailablePlugins()
+	}
+
+	return plugins.ListAvailablePlugins(t)
+}
+
+func (h *TelegrafHandler) handleGetTelegrafPlugins(w http.ResponseWriter, r *http.Request) {
+	ctx := r.Context()
+
+	telPlugins, err := getTelegrafPlugins(r.URL.Query().Get("type"))
+	if err != nil {
+		h.HandleHTTPError(ctx, err, w)
+		return
+	}
+
+	if err := encodeResponse(ctx, w, http.StatusOK, telPlugins); err != nil {
+		logEncodingError(h.log, r, err)
+		return
+	}
+}
+
 func newTelegrafResponse(tc *platform.TelegrafConfig, labels []*platform.Label) *telegrafResponse {
 	res := &telegrafResponse{
 		TelegrafConfig: tc,