Add ability to reference UserPool and IdentityPool resources from another stack.

README.md

@@ -48,11 +48,17 @@ Each entry in the `amplify` section must consist of two parts, with two optional
     * `schema.json` (the AWS AppSync schema in JSON format),
     * `graphql` (a sample GraphQL operations file for codegen),
     * `appsync` (generated code for AppSync - the format is based on the extension)
-* `appClient` is the name of the Amazon Cognito user pool app client configured within the `resources` section of the `serverless.yml` file.  It is optional.
+* `appClient` is the name of the Amazon Cognito user pool app client configured within the `resources` section of the `serverless.yml` file. Define the individual properties for resources on a different stack. It is optional.
+  * `UserPoolId` (reference to a UserPool in another stack)
+  * `ClientId` (the ClientId of a UserPoolClient in another stack)
+  * `ClientSecret` (optional ClientSecret. **Must be entered manually.** CF doesn't support the export of this value.)
+* `identityPool` (optional reference to an IdentityPool in another stack)
 * `s3bucket` is the name of the S3 Bucket used for the S3 transfer utility.  It is optional.  If `disabled`, no S3 bucket information is written to the configuration file.  If not included, the first non-deployed S3 bucket will be used.
 
 For the `appsync` type, the extension of the file is checked.  Supported formats include `flow`, `ts` (for TypeScript), `scala`, and `swift`.
 
+Cross stack `appClient` / `identityPool` configuration only supports `Amazon Cognito User Pools`. Other providers like Google are not tested or implemented yet.
+
 See the `example` directory for a complete sample of an AWS AppSync client deployment with Amazon Cognito user pools.
 
 ### Another Example

index.js

@@ -248,7 +248,14 @@ class ServerlessAmplifyPlugin {
         };
 
         if (fileDetails.hasOwnProperty('appClient')) {
-            const appClient = resources.find(r => r.ResourceType === 'AWS::Cognito::UserPoolClient' && r.LogicalResourceId === fileDetails.appClient);
+            // Look for manually defined appClient configuration
+            // when none is available in the resources because
+            // it is defined in a different stack.
+            let appClient = resources.find(
+                r => r.ResourceType === 'AWS::Cognito::UserPoolClient'
+                && r.LogicalResourceId === fileDetails.appClient
+            ) || this.getManuallyDefinedAppClientConfiguration(fileDetails);
+
             if (typeof appClient !== 'undefined') {
                 config.CognitoUserPool = {
                     Default: {
@@ -271,7 +278,9 @@ class ServerlessAmplifyPlugin {
                 r.metadata.CognitoIdentityProviders.some(({ClientId}) => ClientId === config.CognitoUserPool.Default.AppClientId)
             )
             : undefined;
-        const identityPool = identityPoolForUserPool || identityPools[0];
+
+        const identityPool = identityPoolForUserPool || identityPools[0] || this.getManuallyDefinedIdentityPoolConfiguration(fileDetails);
+
         if (typeof identityPool !== 'undefined') {
             config.CredentialsProvider = {
                 CognitoIdentity: {
@@ -282,7 +291,7 @@ class ServerlessAmplifyPlugin {
                 }
             };
 
-            if (typeof identityPool.metadata.SupportedLoginProviders == 'object') {
+            if (identityPool.metadata.SupportedLoginProviders !== null && typeof identityPool.metadata.SupportedLoginProviders == 'object') {
                 const providers = identityPool.metadata.SupportedLoginProviders;
 
                 // Each authentication provider that is supported for federation  has an entry in
@@ -362,7 +371,14 @@ class ServerlessAmplifyPlugin {
         config.aws_project_region = this.provider.getRegion();
 
         if (fileDetails.hasOwnProperty('appClient')) {
-            const appClient = resources.find(r => r.ResourceType === 'AWS::Cognito::UserPoolClient' && r.LogicalResourceId === fileDetails.appClient);
+            // Look for manually defined appClient configuration
+            // when none is available in the resources because
+            // it is defined in a different stack.
+            let appClient = resources.find(
+                r => r.ResourceType === 'AWS::Cognito::UserPoolClient'
+                && r.LogicalResourceId === fileDetails.appClient
+            ) || this.getManuallyDefinedAppClientConfiguration(fileDetails);
+
             if (typeof appClient !== 'undefined') {
                 config.aws_cognito_region = appClient.metadata.UserPoolClient.UserPoolId.split('_')[0];
                 config.aws_user_pools_id = appClient.metadata.UserPoolClient.UserPoolId;
@@ -382,14 +398,16 @@ class ServerlessAmplifyPlugin {
                 r.metadata.CognitoIdentityProviders.some(({ClientId}) => ClientId === config.aws_user_pools_web_client_id)
             )
             : undefined;
-        const identityPool = identityPoolForUserPool || identityPools[0];
+
+        const identityPool = identityPoolForUserPool || identityPools[0] || this.getManuallyDefinedIdentityPoolConfiguration(fileDetails);
+
         if (typeof identityPool !== 'undefined') {
             if (!config.hasOwnProperty("aws_cognito_region")) {
                 config.aws_cognito_region = identityPool.PhysicalResourceId.split(':')[0];
             }
             config.aws_cognito_identity_pool_id = identityPool.PhysicalResourceId;
 
-            if (typeof identityPool.metadata.SupportedLoginProviders == 'object') {
+            if (identityPool.metadata.SupportedLoginProviders !== null && typeof identityPool.metadata.SupportedLoginProviders == 'object') {
                 const providers = identityPool.metadata.SupportedLoginProviders;
                 const federated = {};
                 let hasFederated = false;
@@ -586,6 +604,67 @@ class ServerlessAmplifyPlugin {
             }
         });
     }
+
+    /**
+     * Checks for and returns a manually defined AppClient cofiguration
+     * 
+     * If the appClient information is defined in a different stack,
+     * we need to be able to define the UserPoolId and ClientId
+     * manually, using available cross stack variable references.
+     * 
+     * @param {FileDetails} fileDetails the file details
+     */
+    getManuallyDefinedAppClientConfiguration(fileDetails) {
+        let appClient;
+
+        try {
+            if (
+                fileDetails.appClient.UserPoolId 
+                && fileDetails.appClient.ClientId
+            ) {
+                appClient = {
+                    metadata: {
+                        UserPoolClient: fileDetails.appClient
+                    }
+                };
+            }
+        } catch (e) {
+            console.log('No manual appClient configuration available.');
+        }
+
+        return appClient;
+    }
+
+    /**
+     * Checks for and returns a manually defined IdentityPool cofiguration
+     * 
+     * If the IdentityPool information is defined in a different stack,
+     * we need to be able to define the IdentityPoolId manually, 
+     * using available cross stack variable references.
+     * 
+     * @param {FileDetails} fileDetails the file details
+     */
+    getManuallyDefinedIdentityPoolConfiguration(fileDetails) {
+        let identityPool;
+
+        try {
+            if (fileDetails.identityPool) {
+                identityPool = {
+                    PhysicalResourceId: fileDetails.identityPool,
+                    metadata: {
+                        // This is not yet supported for manual
+                        // specification of identityPool config.
+                        // Please add.
+                        SupportedLoginProviders: null
+                    }
+                };
+            }
+        } catch (e) {
+            console.log('No manual identityPool configuration available.');
+        }
+
+        return identityPool;
+    }
 }
 
 module.exports = ServerlessAmplifyPlugin;

package.json

@@ -1,6 +1,6 @@
 {
   "name": "aws-amplify-serverless-plugin",
-  "version": "1.4.0",
+  "version": "1.4.2",
   "description": "A plugin for the Serverless Framework that outputs AWS Amplify artifacts based on the deployed resources.",
   "keywords": [
     "serverless",