Add transformation for AWS.CredentialProviderChain (#638)

.changeset/green-flies-sell.md

@@ -0,0 +1,5 @@
+---
+"aws-sdk-js-codemod": patch
+---
+
+Add transformation for AWS.CredentialProviderChain

src/transforms/v2-to-v3/__fixtures__/credentials/chain.input.js

@@ -0,0 +1,3 @@
+import AWS from "aws-sdk";
+
+new AWS.CredentialProviderChain(providers);

src/transforms/v2-to-v3/__fixtures__/credentials/chain.output.js

@@ -0,0 +1,6 @@
+import { chain as providerChain } from "@smithy/property-provider";
+
+// JS SDK v3 switched to credential providers to functions instead of objects.
+// The CredentialProviderChain is now a chain of providers.
+// Reference: https://www.npmjs.com/package/@aws-sdk/credential-providers
+providerChain(providers);

src/transforms/v2-to-v3/apis/index.ts

@@ -6,7 +6,7 @@ export * from "./getS3SignedUrlApiNames";
 export * from "./isS3GetSignedUrlApiUsed";
 export * from "./isS3UploadApiUsed";
 export * from "./removePromiseCalls";
-export * from "./replaceAwsCredentials";
+export * from "./replaceAwsIdentity";
 export * from "./replaceS3GetSignedUrlApi";
 export * from "./replaceS3UploadApi";
 export * from "./replaceWaiterApi";

src/transforms/v2-to-v3/apis/replaceAwsIdentity.ts

@@ -0,0 +1,88 @@
+import { Collection, JSCodeshift, NewExpression } from "jscodeshift";
+import { AWS_CREDENTIALS_MAP } from "../config";
+import { ImportType, addNamedModule } from "../modules";
+
+export interface ReplaceAwsCredentialsOptions {
+  v2GlobalName?: string;
+  importType: ImportType;
+}
+
+const PROVIDER_SWITCH_COMMENT = ` JS SDK v3 switched to credential providers to functions instead of objects.`;
+
+const getNewExpression = (identifier: string, className: string) =>
+  ({
+    type: "NewExpression",
+    callee: {
+      type: "MemberExpression",
+      object: {
+        type: "Identifier",
+        name: identifier,
+      },
+      property: { name: className },
+    },
+  }) as NewExpression;
+
+export const replaceAwsIdentity = (
+  j: JSCodeshift,
+  source: Collection<unknown>,
+  { v2GlobalName, importType }: ReplaceAwsCredentialsOptions
+) => {
+  if (!v2GlobalName) return;
+
+  // ToDo: Add support for AWS.TokenProviderChain in future.
+  const chainNewExpressions = source.find(
+    j.NewExpression,
+    getNewExpression(v2GlobalName, "CredentialProviderChain")
+  );
+  if (chainNewExpressions.size() > 0) {
+    const localName = "providerChain";
+    addNamedModule(j, source, {
+      importType,
+      localName,
+      importedName: "chain",
+      packageName: "@smithy/property-provider",
+    });
+    chainNewExpressions.replaceWith(({ node }) =>
+      j.callExpression.from({
+        callee: j.identifier(localName),
+        comments: [
+          j.commentLine(PROVIDER_SWITCH_COMMENT),
+          j.commentLine(" The CredentialProviderChain is now a chain of providers."),
+          j.commentLine(" Reference: https://www.npmjs.com/package/@aws-sdk/credential-providers"),
+        ],
+        arguments: node.arguments,
+      })
+    );
+  }
+
+  // ToDo: Add support for AWS.Token in future.
+  for (const [v2CredentialsName, v3ProviderName] of Object.entries(AWS_CREDENTIALS_MAP)) {
+    const credsNewExpressions = source.find(
+      j.NewExpression,
+      getNewExpression(v2GlobalName, v2CredentialsName)
+    );
+
+    if (credsNewExpressions.size() > 0) {
+      addNamedModule(j, source, {
+        importType,
+        importedName: v3ProviderName,
+        packageName: "@aws-sdk/credential-providers",
+      });
+      credsNewExpressions.replaceWith(({ node }) =>
+        j.callExpression.from({
+          callee: j.identifier(v3ProviderName),
+          comments: [
+            j.commentLine(PROVIDER_SWITCH_COMMENT),
+            j.commentLine(
+              " This is the closest approximation from codemod of what your application needs."
+            ),
+            j.commentLine(
+              " Reference: https://www.npmjs.com/package/@aws-sdk/credential-providers"
+            ),
+          ],
+          arguments: node.arguments,
+        })
+      );
+    }
+  }
+};

src/transforms/v2-to-v3/transformer.ts

@@ -8,7 +8,7 @@ import {
   replaceS3UploadApi,
   replaceS3GetSignedUrlApi,
   getClientIdentifiersRecord,
-  replaceAwsCredentials,
+  replaceAwsIdentity,
 } from "./apis";
 import { replaceAwsUtilFunctions } from "./aws-util";
 import { replaceClientCreation, replaceDocClientCreation } from "./client-instances";
@@ -92,7 +92,7 @@ const transformer = async (file: FileInfo, api: API) => {
     replaceClientCreation(j, source, { ...v2Options, v3ClientName });
     replaceDocClientCreation(j, source, v2Options);
   }
-  replaceAwsCredentials(j, source, { v2GlobalName, importType });
+  replaceAwsIdentity(j, source, { v2GlobalName, importType });
   replaceAwsUtilFunctions(j, source, v2GlobalName);
   removeGlobalModule(j, source, { v2GlobalName, importType });