feat(cdk): add AppSync GraphQLSchema and pipeline resolvers as hot swappable (#27197)

1. Add GraphQLSchema as another AppSync resource that can be hotswapped
2. For all AppSync resources, accept the change in S3 assets/files instead of just inline code as a candidate for hotswap
3. Make pipeline resolvers hotswappable by resolving the functionId of AppSync functions.

Closes #2659, #24112, #24113.

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: Amplifiyer

packages/aws-cdk/README.md

@@ -421,7 +421,8 @@ Hotswapping is currently supported for the following changes
 - Container asset changes of AWS ECS Services.
 - Website asset changes of AWS S3 Bucket Deployments.
 - Source and Environment changes of AWS CodeBuild Projects.
-- VTL mapping template changes for AppSync Resolvers and Functions
+- VTL mapping template changes for AppSync Resolvers and Functions.
+- Schema changes for AppSync GraphQL Apis.
 
 **⚠ Note #1**: This command deliberately introduces drift in CloudFormation stacks in order to speed up deployments.
 For this reason, only use it for development purposes.

packages/aws-cdk/lib/api/evaluate-cloudformation-template.ts

@@ -413,6 +413,8 @@ const RESOURCE_TYPE_ATTRIBUTES_FORMATS: { [type: string]: { [attribute: string]:
   },
   'AWS::DynamoDB::Table': { Arn: stdSlashResourceArnFmt },
   'AWS::AppSync::GraphQLApi': { ApiId: appsyncGraphQlApiApiIdFmt },
+  'AWS::AppSync::FunctionConfiguration': { FunctionId: appsyncGraphQlFunctionIDFmt },
+  'AWS::AppSync::DataSource': { Name: appsyncGraphQlDataSourceNameFmt },
 };
 
 function iamArnFmt(parts: ArnParts): string {
@@ -440,6 +442,16 @@ function appsyncGraphQlApiApiIdFmt(parts: ArnParts): string {
   return parts.resourceName.split('/')[1];
 }
 
+function appsyncGraphQlFunctionIDFmt(parts: ArnParts): string {
+  // arn:aws:appsync:us-east-1:111111111111:apis/<apiId>/functions/<functionId>
+  return parts.resourceName.split('/')[3];
+}
+
+function appsyncGraphQlDataSourceNameFmt(parts: ArnParts): string {
+  // arn:aws:appsync:us-east-1:111111111111:apis/<apiId>/datasources/<name>
+  return parts.resourceName.split('/')[3];
+}
+
 interface Intrinsic {
   readonly name: string;
   readonly args: any;

packages/aws-cdk/lib/api/hotswap-deployments.ts

@@ -28,6 +28,7 @@ const RESOURCE_DETECTORS: { [key:string]: HotswapDetector } = {
   // AppSync
   'AWS::AppSync::Resolver': isHotswappableAppSyncChange,
   'AWS::AppSync::FunctionConfiguration': isHotswappableAppSyncChange,
+  'AWS::AppSync::GraphQLSchema': isHotswappableAppSyncChange,
 
   'AWS::ECS::TaskDefinition': isHotswappableEcsServiceChange,
   'AWS::CodeBuild::Project': isHotswappableCodeBuildProjectChange,

packages/aws-cdk/lib/api/hotswap/appsync-mapping-templates.ts

@@ -1,29 +1,32 @@
-import { ChangeHotswapResult, classifyChanges, HotswappableChangeCandidate, lowerCaseFirstCharacter, reportNonHotswappableChange, transformObjectKeys } from './common';
+import { GetSchemaCreationStatusRequest, GetSchemaCreationStatusResponse } from 'aws-sdk/clients/appsync';
+import { ChangeHotswapResult, classifyChanges, HotswappableChangeCandidate, lowerCaseFirstCharacter, transformObjectKeys } from './common';
 import { ISDK } from '../aws-auth';
+
 import { EvaluateCloudFormationTemplate } from '../evaluate-cloudformation-template';
 
 export async function isHotswappableAppSyncChange(
   logicalId: string, change: HotswappableChangeCandidate, evaluateCfnTemplate: EvaluateCloudFormationTemplate,
 ): Promise<ChangeHotswapResult> {
   const isResolver = change.newValue.Type === 'AWS::AppSync::Resolver';
   const isFunction = change.newValue.Type === 'AWS::AppSync::FunctionConfiguration';
+  const isGraphQLSchema = change.newValue.Type === 'AWS::AppSync::GraphQLSchema';
 
-  if (!isResolver && !isFunction) {
+  if (!isResolver && !isFunction && !isGraphQLSchema) {
     return [];
   }
 
   const ret: ChangeHotswapResult = [];
-  if (isResolver && change.newValue.Properties?.Kind === 'PIPELINE') {
-    reportNonHotswappableChange(
-      ret,
-      change,
-      undefined,
-      'Pipeline resolvers cannot be hotswapped since they reference the FunctionId of the underlying functions, which cannot be resolved',
-    );
-    return ret;
-  }
 
-  const classifiedChanges = classifyChanges(change, ['RequestMappingTemplate', 'ResponseMappingTemplate']);
+  const classifiedChanges = classifyChanges(change, [
+    'RequestMappingTemplate',
+    'RequestMappingTemplateS3Location',
+    'ResponseMappingTemplate',
+    'ResponseMappingTemplateS3Location',
+    'Code',
+    'CodeS3Location',
+    'Definition',
+    'DefinitionS3Location',
+  ]);
   classifiedChanges.reportNonHotswappablePropertyChanges(ret);
 
   const namesOfHotswappableChanges = Object.keys(classifiedChanges.hotswappableProps);
@@ -49,25 +52,86 @@ export async function isHotswappableAppSyncChange(
 
         const sdkProperties: { [name: string]: any } = {
           ...change.oldValue.Properties,
+          Definition: change.newValue.Properties?.Definition,
+          DefinitionS3Location: change.newValue.Properties?.DefinitionS3Location,
           requestMappingTemplate: change.newValue.Properties?.RequestMappingTemplate,
+          requestMappingTemplateS3Location: change.newValue.Properties?.RequestMappingTemplateS3Location,
           responseMappingTemplate: change.newValue.Properties?.ResponseMappingTemplate,
+          responseMappingTemplateS3Location: change.newValue.Properties?.ResponseMappingTemplateS3Location,
+          code: change.newValue.Properties?.Code,
+          codeS3Location: change.newValue.Properties?.CodeS3Location,
         };
         const evaluatedResourceProperties = await evaluateCfnTemplate.evaluateCfnExpression(sdkProperties);
         const sdkRequestObject = transformObjectKeys(evaluatedResourceProperties, lowerCaseFirstCharacter);
 
+        // resolve s3 location files as SDK doesn't take in s3 location but inline code
+        if (sdkRequestObject.requestMappingTemplateS3Location) {
+          sdkRequestObject.requestMappingTemplate = (await fetchFileFromS3(sdkRequestObject.requestMappingTemplateS3Location, sdk))?.toString('utf8');
+          delete sdkRequestObject.requestMappingTemplateS3Location;
+        }
+        if (sdkRequestObject.responseMappingTemplateS3Location) {
+          sdkRequestObject.responseMappingTemplate = (await fetchFileFromS3(sdkRequestObject.responseMappingTemplateS3Location, sdk))?.toString('utf8');
+          delete sdkRequestObject.responseMappingTemplateS3Location;
+        }
+        if (sdkRequestObject.definitionS3Location) {
+          sdkRequestObject.definition = await fetchFileFromS3(sdkRequestObject.definitionS3Location, sdk);
+          delete sdkRequestObject.definitionS3Location;
+        }
+        if (sdkRequestObject.codeS3Location) {
+          sdkRequestObject.code = await fetchFileFromS3(sdkRequestObject.codeS3Location, sdk);
+          delete sdkRequestObject.codeS3Location;
+        }
+
         if (isResolver) {
           await sdk.appsync().updateResolver(sdkRequestObject).promise();
-        } else {
+        } else if (isFunction) {
+
           const { functions } = await sdk.appsync().listFunctions({ apiId: sdkRequestObject.apiId }).promise();
           const { functionId } = functions?.find(fn => fn.name === physicalName) ?? {};
-          await sdk.appsync().updateFunction({
-            ...sdkRequestObject,
-            functionId: functionId!,
-          }).promise();
+          await simpleRetry(
+            () => sdk.appsync().updateFunction({ ...sdkRequestObject, functionId: functionId! }).promise(),
+            3,
+            'ConcurrentModificationException');
+        } else {
+          let schemaCreationResponse: GetSchemaCreationStatusResponse = await sdk.appsync().startSchemaCreation(sdkRequestObject).promise();
+          while (schemaCreationResponse.status && ['PROCESSING', 'DELETING'].some(status => status === schemaCreationResponse.status)) {
+            await sleep(1000); // poll every second
+            const getSchemaCreationStatusRequest: GetSchemaCreationStatusRequest = {
+              apiId: sdkRequestObject.apiId,
+            };
+            schemaCreationResponse = await sdk.appsync().getSchemaCreationStatus(getSchemaCreationStatusRequest).promise();
+          }
+          if (schemaCreationResponse.status === 'FAILED') {
+            throw new Error(schemaCreationResponse.details);
+          }
         }
       },
     });
   }
 
   return ret;
 }
+
+async function fetchFileFromS3(s3Url: string, sdk: ISDK) {
+  const s3PathParts = s3Url.split('/');
+  const s3Bucket = s3PathParts[2]; // first two are "s3:" and "" due to s3://
+  const s3Key = s3PathParts.splice(3).join('/'); // after removing first three we reconstruct the key
+  return (await sdk.s3().getObject({ Bucket: s3Bucket, Key: s3Key }).promise()).Body;
+}
+
+async function simpleRetry(fn: () => Promise<any>, numOfRetries: number, errorCodeToRetry: string) {
+  try {
+    await fn();
+  } catch (error: any) {
+    if (error && error.code === errorCodeToRetry && numOfRetries > 0) {
+      await sleep(500); // wait half a second
+      await simpleRetry(fn, numOfRetries - 1, errorCodeToRetry);
+    } else {
+      throw error;
+    }
+  }
+}
+
+async function sleep(ms: number) {
+  return new Promise(ok => setTimeout(ok, ms));
+}