feat: adds external account credentials to ADC

oauth2_http/java/com/google/auth/oauth2/GoogleCredentials.java

@@ -31,6 +31,8 @@
 
 package com.google.auth.oauth2;
 
+import static com.google.auth.oauth2.IdentityPoolCredentials.EXTERNAL_ACCOUNT_FILE_TYPE;
+
 import com.google.api.client.json.GenericJson;
 import com.google.api.client.json.JsonFactory;
 import com.google.api.client.json.JsonObjectParser;
@@ -49,8 +51,8 @@
 public class GoogleCredentials extends OAuth2Credentials {
 
   private static final long serialVersionUID = -1522852442442473691L;
-  static final String QUOTA_PROJECT_ID_HEADER_KEY = "x-goog-user-project";
 
+  static final String QUOTA_PROJECT_ID_HEADER_KEY = "x-goog-user-project";
   static final String USER_FILE_TYPE = "authorized_user";
   static final String SERVICE_ACCOUNT_FILE_TYPE = "service_account";
 
@@ -165,6 +167,9 @@ public static GoogleCredentials fromStream(
     if (SERVICE_ACCOUNT_FILE_TYPE.equals(fileType)) {
       return ServiceAccountCredentials.fromJson(fileContents, transportFactory);
     }
+    if (EXTERNAL_ACCOUNT_FILE_TYPE.equals(fileType)) {
+      return ExternalAccountCredentials.fromJson(fileContents, transportFactory);
+    }
     throw new IOException(
         String.format(
             "Error reading credentials from stream, 'type' value '%s' not recognized."

oauth2_http/javatests/com/google/auth/oauth2/AwsCredentialsTest.java

@@ -40,10 +40,12 @@
 
 import com.google.api.client.json.GenericJson;
 import com.google.api.client.json.JsonParser;
+import com.google.auth.TestUtils;
 import com.google.auth.http.HttpTransportFactory;
 import com.google.auth.oauth2.AwsCredentials.AwsCredentialSource;
 import com.google.auth.oauth2.ExternalAccountCredentialsTest.MockExternalAccountCredentialsTransportFactory;
 import java.io.IOException;
+import java.io.InputStream;
 import java.net.URI;
 import java.util.Arrays;
 import java.util.Collection;
@@ -315,15 +317,34 @@ public void createdScoped_clonedCredentialWithAddedScopes() {
     assertEquals(newScopes, newCredentials.getScopes());
   }
 
-  private AwsCredentialSource buildAwsCredentialSource(
+  private static AwsCredentialSource buildAwsCredentialSource(
       MockExternalAccountCredentialsTransportFactory transportFactory) {
     Map<String, Object> credentialSourceMap = new HashMap<>();
-    credentialSourceMap.put("region_url", transportFactory.transport.getAwsRegionEndpoint());
-    credentialSourceMap.put("url", transportFactory.transport.getAwsCredentialsEndpoint());
+    credentialSourceMap.put("region_url", transportFactory.transport.getAwsRegionUrl());
+    credentialSourceMap.put("url", transportFactory.transport.getAwsCredentialsUrl());
     credentialSourceMap.put("regional_cred_verification_url", GET_CALLER_IDENTITY_URL);
     return new AwsCredentialSource(credentialSourceMap);
   }
 
+  static InputStream writeAwsCredentialsStream(String stsUrl, String regionUrl, String metadataUrl)
+      throws IOException {
+    GenericJson json = new GenericJson();
+    json.put("audience", "audience");
+    json.put("subject_token_type", "subjectTokenType");
+    json.put("token_url", stsUrl);
+    json.put("token_info_url", "tokenInfoUrl");
+    json.put("type", ExternalAccountCredentials.EXTERNAL_ACCOUNT_FILE_TYPE);
+
+    GenericJson credentialSource = new GenericJson();
+    credentialSource.put("environment_id", "aws1");
+    credentialSource.put("region_url", regionUrl);
+    credentialSource.put("url", metadataUrl);
+    credentialSource.put("regional_cred_verification_url", GET_CALLER_IDENTITY_URL);
+    json.put("credential_source", credentialSource);
+
+    return TestUtils.jsonToInputStream(json);
+  }
+
   /** Used to test the retrieval of AWS credentials from environment variables. */
   private static class TestAwsCredentials extends AwsCredentials {
 

oauth2_http/javatests/com/google/auth/oauth2/GoogleCredentialsTest.java

@@ -40,6 +40,7 @@
 import com.google.api.client.testing.http.MockHttpTransport;
 import com.google.auth.TestUtils;
 import com.google.auth.http.HttpTransportFactory;
+import com.google.auth.oauth2.IdentityPoolCredentialsTest.MockExternalAccountCredentialsTransportFactory;
 import com.google.common.collect.ImmutableList;
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
@@ -224,6 +225,43 @@ public void fromStream_userNoRefreshToken_throws() throws IOException {
     testFromStreamException(userStream, "refresh_token");
   }
 
+  @Test
+  public void fromStream_identityPoolCredentials_providesToken() throws IOException {
+    MockExternalAccountCredentialsTransportFactory transportFactory =
+        new MockExternalAccountCredentialsTransportFactory();
+    InputStream identityPoolCredentialStream =
+        IdentityPoolCredentialsTest.writeIdentityPoolCredentialsStream(
+            transportFactory.transport.getStsUrl(), transportFactory.transport.getMetadataUrl());
+
+    GoogleCredentials credentials =
+        GoogleCredentials.fromStream(identityPoolCredentialStream, transportFactory);
+
+    assertNotNull(credentials);
+    credentials = credentials.createScoped(SCOPES);
+    Map<String, List<String>> metadata = credentials.getRequestMetadata(CALL_URI);
+    TestUtils.assertContainsBearerToken(metadata, transportFactory.transport.getAccessToken());
+  }
+
+  @Test
+  public void fromStream_awsCredentials_providesToken() throws IOException {
+    MockExternalAccountCredentialsTransportFactory transportFactory =
+        new MockExternalAccountCredentialsTransportFactory();
+
+    InputStream awsCredentialStream =
+        AwsCredentialsTest.writeAwsCredentialsStream(
+            transportFactory.transport.getStsUrl(),
+            transportFactory.transport.getAwsRegionUrl(),
+            transportFactory.transport.getAwsCredentialsUrl());
+
+    GoogleCredentials credentials =
+        GoogleCredentials.fromStream(awsCredentialStream, transportFactory);
+
+    assertNotNull(credentials);
+    credentials = credentials.createScoped(SCOPES);
+    Map<String, List<String>> metadata = credentials.getRequestMetadata(CALL_URI);
+    TestUtils.assertContainsBearerToken(metadata, transportFactory.transport.getAccessToken());
+  }
+
   @Test
   public void createScoped_overloadCallsImplementation() {
     final AtomicReference<Collection<String>> called = new AtomicReference<>();

oauth2_http/javatests/com/google/auth/oauth2/IdentityPoolCredentialsTest.java

@@ -39,11 +39,13 @@
 
 import com.google.api.client.http.HttpTransport;
 import com.google.api.client.json.GenericJson;
+import com.google.auth.TestUtils;
 import com.google.auth.http.HttpTransportFactory;
 import com.google.auth.oauth2.IdentityPoolCredentials.IdentityPoolCredentialSource;
 import java.io.ByteArrayInputStream;
 import java.io.File;
 import java.io.IOException;
+import java.io.InputStream;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
@@ -415,14 +417,30 @@ public void run() {
         e.getMessage());
   }
 
-  @Test
-  public void identityPoolCredentialSource_jsonFormatTypeWithoutSubjectTokenFieldName() {}
+  static InputStream writeIdentityPoolCredentialsStream(String tokenUrl, String url)
+      throws IOException {
+    GenericJson json = new GenericJson();
+    json.put("audience", "audience");
+    json.put("subject_token_type", "subjectTokenType");
+    json.put("token_url", tokenUrl);
+    json.put("token_info_url", "tokenInfoUrl");
+    json.put("type", ExternalAccountCredentials.EXTERNAL_ACCOUNT_FILE_TYPE);
+
+    GenericJson credentialSource = new GenericJson();
+    GenericJson headers = new GenericJson();
+    headers.put("Metadata-Flavor", "Google");
+    credentialSource.put("url", url);
+    credentialSource.put("headers", headers);
+
+    json.put("credential_source", credentialSource);
+    return TestUtils.jsonToInputStream(json);
+  }
 
-  private IdentityPoolCredentialSource buildUrlBasedCredentialSource(String url) {
+  private static IdentityPoolCredentialSource buildUrlBasedCredentialSource(String url) {
     return buildUrlBasedCredentialSource(url, /* formatMap= */ null);
   }
 
-  private IdentityPoolCredentialSource buildUrlBasedCredentialSource(
+  private static IdentityPoolCredentialSource buildUrlBasedCredentialSource(
       String url, Map<String, String> formatMap) {
     Map<String, Object> credentialSourceMap = new HashMap<>();
     Map<String, String> headers = new HashMap<>();

oauth2_http/javatests/com/google/auth/oauth2/MockExternalAccountCredentialsTransport.java

@@ -228,11 +228,11 @@ public String getMetadataUrl() {
     return METADATA_SERVER_URL;
   }
 
-  public String getAwsCredentialsEndpoint() {
+  public String getAwsCredentialsUrl() {
     return AWS_CREDENTIALS_URL;
   }
 
-  public String getAwsRegionEndpoint() {
+  public String getAwsRegionUrl() {
     return AWS_REGION_URL;
   }