feat: some tweaks to the actions registry and implementing some of the actions client

Signed-off-by: benjdlambert <ben@blam.sh>

packages/backend-plugin-api/src/services/definitions/ActionsRegistryService.ts

@@ -23,25 +23,6 @@ export type ActionsRegistryActionContext<TInputSchema extends ZodType> = {
   credentials: BackstageCredentials;
 };
 
-// todo: opaque type?
-export type ActionsRegistryAction<
-  TInputSchema extends ZodType,
-  TOutputSchema extends ZodType,
-> = {
-  id: string;
-  name: string;
-  title: string;
-  description: string;
-  // todo: what about additional metadata?
-  schema?: {
-    input?: TInputSchema;
-    output?: TOutputSchema;
-  };
-  action: (
-    context: ActionsRegistryActionContext<TInputSchema>,
-  ) => Promise<TOutputSchema extends ZodType ? z.infer<TOutputSchema> : void>;
-};
-
 export type ActionsRegistryActionOptions<
   TInputSchema extends ZodType,
   TOutputSchema extends ZodType,
@@ -49,14 +30,15 @@ export type ActionsRegistryActionOptions<
   name: string;
   title: string;
   description: string;
-  // todo: what about additional metadata?
   schema?: {
     input?: (zod: typeof z) => TInputSchema;
     output?: (zod: typeof z) => TOutputSchema;
   };
   action: (
     context: ActionsRegistryActionContext<TInputSchema>,
-  ) => Promise<TOutputSchema extends ZodType ? z.infer<TOutputSchema> : void>;
+  ) => Promise<
+    TOutputSchema extends ZodType ? { output: z.infer<TOutputSchema> } : void
+  >;
 };
 
 export interface ActionsRegistryService {

packages/backend-plugin-api/src/services/definitions/ActionsService.ts

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2025 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import { JsonObject, JsonValue } from '@backstage/types';
+import { JSONSchema7 } from 'json-schema';
+
+export type ActionsServiceAction = {
+  id: string;
+  name: string;
+  title: string;
+  description: string;
+  schema?: {
+    input?: JSONSchema7;
+    output?: JSONSchema7;
+  };
+};
+
+export interface ActionsService {
+  listActions: () => Promise<{ actions: ActionsServiceAction[] }>;
+  invokeAction(opts: {
+    id: string;
+    input?: JsonObject;
+  }): Promise<{ output: JsonValue }>;
+}

packages/backend-plugin-api/src/services/definitions/coreServices.ts

@@ -36,7 +36,22 @@ export namespace coreServices {
   });
 
   /**
-   * Service for registering and managing actions.
+   * Service for calling distributed actions
+   *
+   * See {@link ActionsService}
+   * and {@link https://backstage.io/docs/backend-system/core-services/actions | the service docs}
+   * for more information.
+   *
+   * @public
+   */
+  export const actions = createServiceRef<
+    import('./ActionsService').ActionsService
+  >({
+    id: 'core.actions',
+  });
+
+  /**
+   * Service for registering and managing distributed actions.
    *
    * See {@link ActionsRegistryService}
    * and {@link https://backstage.io/docs/backend-system/core-services/actions-registry | the service docs}

packages/backend-plugin-api/src/services/definitions/index.ts

@@ -18,8 +18,9 @@ export type {
   ActionsRegistryService,
   ActionsRegistryActionOptions,
   ActionsRegistryActionContext,
-  ActionsRegistryAction,
 } from './ActionsRegistryService';
+
+export type { ActionsService, ActionsServiceAction } from './ActionsService';
 export type {
   AuditorService,
   AuditorServiceCreateEventOptions,