Add Data Connect resolver snippets (#422)

* Add Data Connect resolver snippets

* Update lock file

Author: kevinthecheung

functions/dataconnect-resolver/fwdChatToEmail.ts

@@ -0,0 +1,58 @@
+// Stub Data Connect function. Normally, this would be generated by the Firebase CLI.
+async function getChatMessage({ chatMessageId }: { chatMessageId: string }): Promise<{ data: { chatMessage?: { content?: string } } }> {
+  return {
+    data: {
+      chatMessage: {
+        content: ""
+      }
+    }
+  };
+}
+
+// [START fdc_forward_to_email_resolver]
+import { getAuth } from "firebase-admin/auth";
+import {
+    FirebaseContext,
+    GraphqlServerOptions,
+    onGraphRequest
+} from "firebase-functions/dataconnect/graphql";
+
+const opts: GraphqlServerOptions = {
+ schemaFilePath: "dataconnect/schema_resolver/schema.gql",
+ resolvers: {
+   query: {
+     async forwardToEmail(
+       _parent: unknown,
+       args: Record<string, unknown>,
+       _contextValue: FirebaseContext,
+       _info: unknown
+     ) {
+       const chatMessageId = args.chatMessageId as string;
+
+       let decodedToken;
+       try {
+         decodedToken = await getAuth().verifyIdToken(_contextValue.auth.token ?? "");
+       } catch (error) {
+         return false;
+       }
+
+       const email = decodedToken.email;
+       if (!email) {
+         return false;
+       }
+
+       // Call generated admin SDK.
+       const response = await getChatMessage({chatMessageId});
+       const messageContent = response.data.chatMessage?.content;
+
+       // Here you call the cloud service of your choice to send the email with
+       // the message content.
+
+       return true;
+     }
+   },
+ },
+};
+
+export const resolver = onGraphRequest(opts);
+// [END fdc_forward_to_email_resolver]

functions/dataconnect-resolver/index.ts

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+// [START fdc_resolver_skeleton]
+import {
+  FirebaseContext,
+  GraphqlServerOptions,
+  onGraphRequest,
+} from "firebase-functions/dataconnect/graphql";
+
+const opts: GraphqlServerOptions = {
+  // Points to the schema you defined earlier, relative to the root of your
+  // Firebase project.
+  schemaFilePath: "dataconnect/schema_resolver/schema.gql",
+  resolvers: {
+    query: {
+      // This resolver function populates the data for the "publicProfile" field
+      // defined in your GraphQL schema located at schemaFilePath.
+      publicProfile(
+        _parent: unknown,
+        args: Record<string, unknown>,
+        _contextValue: FirebaseContext,
+        _info: unknown
+      ) {
+        const userId = args.userId;
+
+        // Here you would use the user ID to retrieve the user profile from your data
+        // store. In this example, we just return a hard-coded value.
+
+        return {
+          name: "Ulysses von Userberg",
+          photoUrl: "https://example.com/profiles/12345/photo.jpg",
+          bioLine: "Just a guy on a mountain. Ski fanatic.",
+        };
+      },
+    },
+    mutation: {
+      // This resolver function updates data for the "updatePublicProfile" field
+      // defined in your GraphQL schema located at schemaFilePath.
+      updatePublicProfile(
+        _parent: unknown,
+        args: Record<string, unknown>,
+        _contextValue: FirebaseContext,
+        _info: unknown
+      ) {
+        const { userId, name, photoUrl, bioLine } = args;
+
+        // Here you would update in your datastore the user's profile using the
+        // arguments that were passed. In this example, we just return the profile
+        // as though the operation had been successful.
+
+        return { name, photoUrl, bioLine };
+      },
+    },
+  },
+};
+
+export const resolver = onGraphRequest(opts);
+// [END fdc_resolver_skeleton]

functions/dataconnect-resolver/package.json

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+{
+  "name": "dataconnect-resolver",
+  "version": "1.0.0",
+  "description": "Skeleton implementations of Data Connect custom resolvers",
+  "main": "index.js",
+  "license": "Apache-2.0",
+  "scripts": {
+    "compile": "cp ../../tsconfig.template.json ./tsconfig.json && tsc"
+  },
+  "dependencies": {
+    "firebase-admin": "^11.11.1",
+    "firebase-functions": "^7.1.0"
+  }
+}

functions/dataconnect-resolver/sendEmail.ts

@@ -0,0 +1,30 @@
+// [START fdc_send_email_resolver]
+import {
+  FirebaseContext,
+  GraphqlServerOptions,
+  onGraphRequest,
+} from "firebase-functions/dataconnect/graphql";
+
+const opts: GraphqlServerOptions = {
+  schemaFilePath: "dataconnect/schema_resolver/schema.gql",
+  resolvers: {
+    mutation: {
+      sendEmail(
+        _parent: unknown,
+        args: Record<string, unknown>,
+        _contextValue: FirebaseContext,
+        _info: unknown
+      ) {
+        const { friendId, content } = args;
+
+        // Look up the friend's email address and call the cloud service of your
+        // choice to send the friend an email with the given content.
+
+       return true;
+      },
+    },
+  },
+};
+
+export const resolver = onGraphRequest(opts);
+// [END fdc_send_email_resolver]