[POC] feature: manage stack mappings to unblock api expansion over time

packages/amplify-category-api/amplify-plugin.json

@@ -12,7 +12,9 @@
     "rebuild",
     "remove",
     "update",
-    "help"
+    "help",
+    "snapshot-stack-mappings",
+    "assign-stack-mappings"
   ],
   "commandAliases": {
     "configure": "update"

packages/amplify-category-api/src/commands/api.ts

@@ -56,6 +56,14 @@ export const run = async (context: $TSContext) => {
       name: 'override',
       description: 'Generates overrides file to apply custom modifications to CloudFormation',
     },
+    {
+      name: 'snapshot-stack-mappings',
+      description: 'Snapshots the stack mappings for the current project',
+    },
+    {
+      name: 'assign-stack-mappings',
+      description: 'Assign stack mappings for the newly built resources',
+    },
   ];
 
   context.amplify.showHelp(header, commands);

packages/amplify-category-api/src/commands/api/assign-stack-mappings.ts

@@ -0,0 +1,15 @@
+import { $TSContext} from '@aws-amplify/amplify-cli-core';
+import { assignStackMappings } from '../../provider-utils/awscloudformation/stack-mapping-manager';
+
+/**
+ * Pull all resolver and functions from the current cloud backend and snapshot them in the transform.conf.json file.
+ * `amplify pull` may need to be run first.
+ */
+export const run = async (context: $TSContext): Promise<void> => {
+  const stackName = context.parameters?.options?.['stack-name'];
+  if (!stackName) {
+    throw new Error('need to provide --stack-name <STACK NAME>');
+  }
+
+  return assignStackMappings(stackName);
+};

packages/amplify-category-api/src/commands/api/snapshot-stack-mappings.ts

@@ -0,0 +1,8 @@
+import { $TSContext } from '@aws-amplify/amplify-cli-core';
+import { snapshotStackMappings } from '../../provider-utils/awscloudformation/stack-mapping-manager';
+
+/**
+ * Pull all resolver and functions from the current cloud backend and snapshot them in the transform.conf.json file.
+ * `amplify pull` may need to be run first.
+ */
+export const run = async (context: $TSContext): Promise<void> => snapshotStackMappings();

packages/amplify-category-api/src/provider-utils/awscloudformation/stack-mapping-manager.ts

@@ -0,0 +1,108 @@
+import { pathManager, stateManager } from '@aws-amplify/amplify-cli-core';
+import { getAppSyncResourceName } from '../../provider-utils/awscloudformation/utils/amplify-meta-utils';
+import { readFromPath } from 'graphql-transformer-core/lib/util/fileUtils';
+import { loadConfig, writeConfig } from 'graphql-transformer-core';
+import * as fs from 'fs-extra';
+import * as path from 'path';
+
+/**
+ * Pull all resolver and functions from the current cloud backend and snapshot them in the transform.conf.json file.
+ * `amplify pull` may need to be run first.
+ */
+export const snapshotStackMappings = async (): Promise<void> => {
+  const apiName = getAppSyncResourceName(stateManager.getMeta());
+  if (!apiName) {
+    throw new Error('Could not find api name.');
+  }
+
+  const currentApiStacksPath = path.join(pathManager.getCurrentCloudBackendDirPath(), 'api', apiName, 'build', 'stacks');
+  if (!fs.pathExistsSync(currentApiStacksPath)) {
+    throw new Error('Could not find current cloud backend api stacks path.');
+  }
+
+  const apiPath = path.join(pathManager.getAmplifyDirPath(), 'backend', 'api', apiName);
+  if (!fs.pathExistsSync(apiPath)) {
+    throw new Error('Could not find api path.');
+  }
+
+  const currentApiStacks: Record<string, string> = await readFromPath(currentApiStacksPath);
+
+  const getResourceIdsForTypes = (stackDefinition: any, resourceTypes: string[]): string[] => {
+    const resourceTypeSet = new Set(resourceTypes);
+    return Object.entries(stackDefinition.Resources)
+      .filter(([_, resource]: [string, any]) => resourceTypeSet.has(resource.Type))
+      .map(([resourceName, _]) => resourceName);
+  };
+
+  const stackMappings = Object.fromEntries(Object.entries(currentApiStacks).flatMap(([stackFileName, stackContentsString]) => {
+    const stackName = stackFileName.split('.')[0];
+    const stackContents = JSON.parse(stackContentsString);
+    return getResourceIdsForTypes(stackContents, ['AWS::AppSync::FunctionConfiguration', 'AWS::AppSync::Resolver'])
+      .map(id => [id, stackName]);
+  }));
+
+  const config: any = await loadConfig(apiPath);
+
+  Object.entries(stackMappings).forEach(([resourceId, stackName]) => {
+    if (!config.StackMapping) {
+      config.StackMapping = {};
+    }
+    if (!(resourceId in config.StackMapping)) {
+      config.StackMapping[resourceId] = stackName;
+    }
+  });
+
+  await writeConfig(apiPath, config);
+};
+
+/**
+ * Pull all resolver and functions from the current cloud backend and snapshot them in the transform.conf.json file.
+ * `amplify pull` may need to be run first.
+ */
+export const assignStackMappings = async (stackNameAssignment: string): Promise<void> => {
+  await snapshotStackMappings();
+
+  const apiName = getAppSyncResourceName(stateManager.getMeta());
+  if (!apiName) {
+    throw new Error('Could not find api name.');
+  }
+
+  const apiPath = path.join(pathManager.getAmplifyDirPath(), 'backend', 'api', apiName);
+  if (!fs.pathExistsSync(apiPath)) {
+    throw new Error('Could not find api path.');
+  }
+
+  const buildApiStacksPath = path.join(apiPath, 'build', 'stacks');
+  if (!fs.pathExistsSync(buildApiStacksPath)) {
+    throw new Error('need to build first, run `amplify api gql-compile`');
+  }
+
+  const apiStacks: Record<string, string> = await readFromPath(buildApiStacksPath);
+
+  const getResourceIdsForTypes = (stackDefinition: any, resourceTypes: string[]): string[] => {
+    const resourceTypeSet = new Set(resourceTypes);
+    return Object.entries(stackDefinition.Resources)
+      .filter(([_, resource]: [string, any]) => resourceTypeSet.has(resource.Type))
+      .map(([resourceName, _]) => resourceName);
+  };
+
+  const stackMappings = Object.fromEntries(Object.entries(apiStacks).flatMap(([stackFileName, stackContentsString]) => {
+    const stackName = stackFileName.split('.')[0];
+    const stackContents = JSON.parse(stackContentsString);
+    return getResourceIdsForTypes(stackContents, ['AWS::AppSync::FunctionConfiguration', 'AWS::AppSync::Resolver'])
+      .map(id => [id, stackName]);
+  }));
+
+  const config: any = await loadConfig(apiPath);
+
+  Object.entries(stackMappings).forEach(([resourceId, stackName]) => {
+    if (!config.StackMapping) {
+      config.StackMapping = {};
+    }
+    if (!(resourceId in config.StackMapping)) {
+      config.StackMapping[resourceId] = stackNameAssignment;
+    }
+  });
+
+  await writeConfig(apiPath, config);
+};