Add #set and #toJSON to RC ServerTemplate (#2522)

* Add #set on ServerTemplate to allow for setting and caching a server template

* Simplify initServerTemplate to make use of the new setter

* Update tests

* Address comments and feedback

* Update API docs

* Add export for new type ServerTemplateDataType to index.ts

* Update some inline comments

Author: trekforever

etc/firebase-admin.remote-config.api.md

@@ -45,7 +45,7 @@ export interface InAppDefaultValue {
 
 // @public
 export interface InitServerTemplateOptions extends GetServerTemplateOptions {
-    template?: ServerTemplateData | string;
+    template?: ServerTemplateDataType;
 }
 
 // @public
@@ -183,9 +183,10 @@ export interface ServerConfig {
 
 // @public
 export interface ServerTemplate {
-    cache: ServerTemplateData;
     evaluate(context?: EvaluationContext): ServerConfig;
     load(): Promise<void>;
+    set(template: ServerTemplateDataType): void;
+    toJSON(): ServerTemplateData;
 }
 
 // @public
@@ -198,6 +199,9 @@ export interface ServerTemplateData {
     version?: Version;
 }
 
+// @public
+export type ServerTemplateDataType = ServerTemplateData | string;
+
 // @public
 export type TagColor = 'BLUE' | 'BROWN' | 'CYAN' | 'DEEP_ORANGE' | 'GREEN' | 'INDIGO' | 'LIME' | 'ORANGE' | 'PINK' | 'PURPLE' | 'TEAL';
 

src/remote-config/index.ts

@@ -50,6 +50,7 @@ export {
   ServerConfig,
   ServerTemplate,
   ServerTemplateData,
+  ServerTemplateDataType,
   TagColor,
   Value,
   ValueSource,

src/remote-config/remote-config-api.ts

@@ -364,6 +364,13 @@ export interface GetServerTemplateOptions {
   defaultConfig?: DefaultConfig;
 }
 
+/**
+ * Represents the type of a Remote Config server template that can be set on
+ * {@link ServerTemplate}. This can either be a {@link ServerTemplateData} object
+ * or a template JSON string.
+ */
+export type ServerTemplateDataType = ServerTemplateData | string;
+
 /**
  * Represents optional arguments that can be used when instantiating
  * {@link ServerTemplate} synchonously.
@@ -375,22 +382,14 @@ export interface InitServerTemplateOptions extends GetServerTemplateOptions {
    * example, customers can reduce initialization latency by pre-fetching and
    * caching template data and then using this option to initialize the SDK with
    * that data.
-   * The template can be initialized with either a {@link ServerTemplateData}
-   * object or a JSON string.
    */
-  template?: ServerTemplateData|string,
+  template?: ServerTemplateDataType,
 }
 
 /**
  * Represents a stateful abstraction for a Remote Config server template.
  */
 export interface ServerTemplate {
-
-  /**
-   * Cached {@link ServerTemplateData}.
-   */
-  cache: ServerTemplateData;
-
   /**
    * Evaluates the current template to produce a {@link ServerConfig}.
    */
@@ -401,6 +400,17 @@ export interface ServerTemplate {
    * project's {@link ServerTemplate}.
    */
   load(): Promise<void>;
+
+  /**
+   * Sets and caches a {@link ServerTemplateData} or a JSON string representing
+   * the server template
+   */
+  set(template: ServerTemplateDataType): void;
+
+  /**
+   * Returns a JSON representation of {@link ServerTemplateData}
+   */
+  toJSON(): ServerTemplateData;
 }
 
 /**

src/remote-config/remote-config.ts

@@ -40,6 +40,7 @@ import {
   DefaultConfig,
   GetServerTemplateOptions,
   InitServerTemplateOptions,
+  ServerTemplateDataType,
 } from './remote-config-api';
 import { isString } from 'lodash';
 
@@ -200,20 +201,9 @@ export class RemoteConfig {
   public initServerTemplate(options?: InitServerTemplateOptions): ServerTemplate {
     const template = new ServerTemplateImpl(
       this.client, new ConditionEvaluator(), options?.defaultConfig);
+
     if (options?.template) {
-      // Check and instantiates the template via a json string
-      if (isString(options?.template)) {
-        try {
-          template.cache = new ServerTemplateDataImpl(JSON.parse(options?.template));
-        } catch (e) {
-          throw new FirebaseRemoteConfigError(
-            'invalid-argument',
-            `Failed to parse the JSON string: ${options?.template}. ` + e
-          );
-        }
-      } else {
-        template.cache = options?.template;
-      }
+      template.set(options?.template);
     }
     return template;
   }
@@ -307,7 +297,7 @@ class RemoteConfigTemplateImpl implements RemoteConfigTemplate {
  * Remote Config dataplane template data implementation.
  */
 class ServerTemplateImpl implements ServerTemplate {
-  public cache: ServerTemplateData;
+  private cache: ServerTemplateData;
   private stringifiedDefaultConfig: {[key: string]: string} = {};
 
   constructor(
@@ -333,6 +323,27 @@ class ServerTemplateImpl implements ServerTemplate {
       });
   }
 
+  /**
+   * Parses a {@link ServerTemplateDataType} and caches it.
+   */
+  public set(template: ServerTemplateDataType): void {
+    let parsed;
+    if (isString(template)) {
+      try {
+        parsed = JSON.parse(template);
+      } catch (e) {
+        // Transforms JSON parse errors to Firebase error.
+        throw new FirebaseRemoteConfigError(
+          'invalid-argument',
+          `Failed to parse the JSON string: ${template}. ` + e);
+      }
+    } else {
+      parsed = template;
+    }
+    // Throws template parse errors.
+    this.cache = new ServerTemplateDataImpl(parsed);
+  }
+
   /**
    * Evaluates the current template in cache to produce a {@link ServerConfig}.
    */
@@ -402,6 +413,13 @@ class ServerTemplateImpl implements ServerTemplate {
 
     return new ServerConfigImpl(configValues);
   }
+
+  /**
+   * @returns JSON representation of the server template
+   */
+  public toJSON(): ServerTemplateData {
+    return this.cache;
+  }
 }
 
 class ServerConfigImpl implements ServerConfig {