feat: Add GCP auth login (Correctly)

pom.xml

@@ -82,7 +82,7 @@
     <dependency>
       <groupId>ch.qos.logback</groupId>
       <artifactId>logback-core</artifactId>
-      <version>1.5.13</version>
+      <version>1.5.19</version>
     </dependency>
 
     <dependency>
@@ -95,7 +95,7 @@
     <dependency>
       <groupId>ch.qos.logback</groupId>
       <artifactId>logback-classic</artifactId>
-      <version>1.5.6</version>
+      <version>1.5.19</version>
     </dependency>
 
     <!--    HTTP request dependencies-->
@@ -130,6 +130,15 @@
       <version>2.34.8</version>
       <optional>true</optional>
     </dependency>
+
+    <!--    GCP dependencies-->
+    <dependency>
+      <groupId>com.google.auth</groupId>
+      <artifactId>google-auth-library-oauth2-http</artifactId>
+      <version>1.20.0</version>
+      <optional>true</optional>
+  </dependency>
+
     <!--    Testing dependencies-->
     <dependency>
       <groupId>org.junit.jupiter</groupId>

src/main/java/com/infisical/sdk/auth/GCPAuthProvider.java

@@ -0,0 +1,52 @@
+package com.infisical.sdk.auth;
+
+import java.net.UnknownHostException;
+import java.util.Arrays;
+import java.util.HashMap;
+
+import com.google.auth.oauth2.GoogleCredentials;
+import com.google.auth.oauth2.IdTokenCredentials;
+import com.google.auth.oauth2.IdTokenProvider;
+import com.google.auth.oauth2.IdTokenProvider.Option;
+import com.infisical.sdk.util.InfisicalException;
+
+public class GCPAuthProvider {
+
+    public static HashMap<String,String> getGCPAuthInput(String identityId) throws InfisicalException{
+
+        if ( identityId == null || identityId.isEmpty() )
+
+            throw new InfisicalException( "Infisical Identity ID is required");
+
+        try{
+
+            // This will fetch credentials from environment variable named GOOGLE_APPLICATION_CREDENTIALS or
+            // or if it's running in a GCP instance it will get them from the instance itself (GCP service account attached) 
+            GoogleCredentials googleCredentials = GoogleCredentials.getApplicationDefault();
+
+            IdTokenCredentials idTokenCredentials =
+                IdTokenCredentials.newBuilder()
+                    .setIdTokenProvider((IdTokenProvider) googleCredentials)
+                    .setTargetAudience(identityId)
+                    .setOptions(Arrays.asList(Option.FORMAT_FULL, Option.LICENSES_TRUE))
+                    .build();
+
+            // Get the ID token.
+            String idToken = idTokenCredentials.refreshAccessToken().getTokenValue();
+
+            // Body cannot be a string so used a HashMap, you can use builder, POJO etc
+            HashMap<String, String> body =  new HashMap<>();
+              body.put("identityId", identityId);
+              body.put("jwt", idToken);
+
+            return body;
+
+        } catch (Exception e){
+            if (e.getCause() instanceof UnknownHostException) {
+                throw new InfisicalException("No network connection."); 
+            }
+            throw new InfisicalException("Failed to fetch Google credentials: " + e.getMessage());
+        }
+
+    }
+}

src/main/java/com/infisical/sdk/resources/AuthClient.java

@@ -2,6 +2,7 @@
 
 import com.infisical.sdk.api.ApiClient;
 import com.infisical.sdk.auth.AwsAuthProvider;
+import com.infisical.sdk.auth.GCPAuthProvider;
 import com.infisical.sdk.models.AwsAuthLoginInput;
 import com.infisical.sdk.models.LdapAuthLoginInput;
 import com.infisical.sdk.models.MachineIdentityCredential;
@@ -56,6 +57,19 @@ public void AwsAuthLogin(AwsAuthLoginInput input) throws InfisicalException {
     this.onAuthenticate.accept(credential.getAccessToken());
   }
 
+  public void GCPAuthLogin(String identityId) throws InfisicalException {
+
+    if (identityId == null || identityId.isEmpty())
+
+      throw new InfisicalException("Infisical Identity ID is required");
+
+    var url = String.format("%s%s", this.apiClient.GetBaseUrl(), "/api/v1/auth/gcp-auth/login");
+
+    var input = GCPAuthProvider.getGCPAuthInput(identityId);
+    var credential = this.apiClient.post(url, input, MachineIdentityCredential.class);
+    this.onAuthenticate.accept(credential.getAccessToken());
+  }
+
   public void SetAccessToken(String accessToken) {
     this.onAuthenticate.accept(accessToken);
   }

src/test/java/com/infisical/sdk/auth/GCPAuthIntegrationTest.java

@@ -0,0 +1,59 @@
+package com.infisical.sdk.auth;
+
+import com.infisical.sdk.InfisicalSdk;
+import com.infisical.sdk.config.SdkConfig;
+import com.infisical.sdk.util.EnvironmentVariables;
+import org.junit.jupiter.api.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class GCPAuthIntegrationTest {
+
+    private static final Logger logger = LoggerFactory.getLogger(GCPAuthIntegrationTest.class);
+    @Test
+    public void testGCPAuthAndFetchSecrets() {
+
+        try {
+
+            // Load env variables
+            var envVars = new EnvironmentVariables();
+
+            // Get Machine Identity Id
+            String machineIdentityId = System.getenv("INFISICAL_MACHINE_IDENTITY_ID");
+
+
+            // Check if env variable machine identity is set, others are already tested via env tests
+            assertNotNull(machineIdentityId, "INFISICAL_MACHINE_IDENTITY_ID env variable must be set");
+assertFalse(machineIdentityId.isEmpty(), "INFISICAL_MACHINE_IDENTITY_ID env variable must not be empty");
+
+
+            // Create SDK instance
+            var sdk = new InfisicalSdk(new SdkConfig.Builder()
+                    .withSiteUrl(envVars.getSiteUrl())
+                    .build()
+            );
+
+            // Authenticate using GCP Auth
+            assertDoesNotThrow(() -> {
+                sdk.Auth().GCPAuthLogin(machineIdentityId);
+            });
+
+            // Test if we have correctly logged in and we can list the secrets
+            var secrets = sdk.Secrets().ListSecrets(
+                                    envVars.getProjectId(), 
+                                    "dev", 
+                                    "/",
+                                    null,
+                                    null,
+                                    null);
+
+            logger.info("TestGCPAuth Successful");
+            logger.info("Secrets length :  {}", secrets.size());
+
+        } catch (Exception e) {
+            throw new AssertionError(e);
+        }
+    }
+}