PR fixes

Author: lahirumaramba

src/main/java/com/google/firebase/remoteconfig/FirebaseRemoteConfigClientImpl.java

@@ -25,7 +25,6 @@
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableMap;
-import com.google.firebase.ErrorCode;
 import com.google.firebase.FirebaseApp;
 import com.google.firebase.FirebaseException;
 import com.google.firebase.ImplFirebaseTrampolines;
@@ -38,7 +37,6 @@
 import com.google.firebase.remoteconfig.internal.RemoteConfigServiceErrorResponse;
 
 import java.io.IOException;
-import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 
@@ -47,26 +45,28 @@
  */
 final class FirebaseRemoteConfigClientImpl implements FirebaseRemoteConfigClient {
 
-  private static final String RC_URL = "https://firebaseremoteconfig.googleapis.com/v1/projects/%s/remoteConfig";
+  private static final String REMOTE_CONFIG_URL = "https://firebaseremoteconfig.googleapis.com/v1/projects/%s/remoteConfig";
 
   private static final Map<String, String> COMMON_HEADERS =
           ImmutableMap.of(
                   "X-GOOG-API-FORMAT-VERSION", "2",
                   "X-Firebase-Client", "fire-admin-java/" + SdkUtils.getVersion(),
+                  // There is a known issue in which the ETag is not properly returned in cases
+                  // where the request does not specify a compression type. Currently, it is
+                  // required to include the header `Accept-Encoding: gzip` or equivalent in all
+                  // requests. https://firebase.google.com/docs/remote-config/use-config-rest#etag_usage_and_forced_updates
                   "Accept-Encoding", "gzip"
           );
 
-  private final String rcSendUrl;
+  private final String remoteConfigUrl;
   private final HttpRequestFactory requestFactory;
-  private final HttpRequestFactory childRequestFactory;
   private final JsonFactory jsonFactory;
   private final ErrorHandlingHttpClient<FirebaseRemoteConfigException> httpClient;
 
   private FirebaseRemoteConfigClientImpl(Builder builder) {
     checkArgument(!Strings.isNullOrEmpty(builder.projectId));
-    this.rcSendUrl = String.format(RC_URL, builder.projectId);
+    this.remoteConfigUrl = String.format(REMOTE_CONFIG_URL, builder.projectId);
     this.requestFactory = checkNotNull(builder.requestFactory);
-    this.childRequestFactory = checkNotNull(builder.childRequestFactory);
     this.jsonFactory = checkNotNull(builder.jsonFactory);
     HttpResponseInterceptor responseInterceptor = builder.responseInterceptor;
     RemoteConfigErrorHandler errorHandler = new RemoteConfigErrorHandler(this.jsonFactory);
@@ -75,49 +75,34 @@ private FirebaseRemoteConfigClientImpl(Builder builder) {
   }
 
   @VisibleForTesting
-  String getRcSendUrl() {
-    return rcSendUrl;
+  String getRemoteConfigUrl() {
+    return remoteConfigUrl;
   }
 
   @VisibleForTesting
   HttpRequestFactory getRequestFactory() {
     return requestFactory;
   }
 
-  @VisibleForTesting
-  HttpRequestFactory getChildRequestFactory() {
-    return childRequestFactory;
-  }
-
   @VisibleForTesting
   JsonFactory getJsonFactory() {
     return jsonFactory;
   }
 
   @Override
   public RemoteConfigTemplate getTemplate() throws FirebaseRemoteConfigException {
-    HttpRequestInfo request = HttpRequestInfo.buildGetRequest(rcSendUrl)
+    HttpRequestInfo request = HttpRequestInfo.buildGetRequest(remoteConfigUrl)
             .addAllHeaders(COMMON_HEADERS);
     IncomingHttpResponse response = httpClient.send(request);
     RemoteConfigTemplate parsed = httpClient.parse(response, RemoteConfigTemplate.class);
 
     List<String> etagList = (List<String>) response.getHeaders().get("etag");
-
-    if (etagList == null || etagList.isEmpty()) {
-      throw new FirebaseRemoteConfigException(
-              ErrorCode.INTERNAL,
-              "ETag header is not available in the server response.", null, null,
-              RemoteConfigErrorCode.INTERNAL);
-    }
+    checkArgument(!(etagList == null || etagList.isEmpty()),
+            "ETag header is not available in the server response.");
 
     String etag = etagList.get(0);
-
-    if (Strings.isNullOrEmpty(etag)) {
-      throw new FirebaseRemoteConfigException(
-              ErrorCode.INTERNAL,
-              "ETag header is not available in the server response.", null, null,
-              RemoteConfigErrorCode.INTERNAL);
-    }
+    checkArgument(!Strings.isNullOrEmpty(etag),
+            "ETag header is not available in the server response.");
 
     parsed.setETag(etag);
     return parsed;
@@ -133,7 +118,6 @@ static FirebaseRemoteConfigClientImpl fromApp(FirebaseApp app) {
     return FirebaseRemoteConfigClientImpl.builder()
             .setProjectId(projectId)
             .setRequestFactory(ApiClientUtils.newAuthorizedRequestFactory(app))
-            .setChildRequestFactory(ApiClientUtils.newUnauthorizedRequestFactory(app))
             .setJsonFactory(app.getOptions().getJsonFactory())
             .build();
   }
@@ -146,7 +130,6 @@ static final class Builder {
 
     private String projectId;
     private HttpRequestFactory requestFactory;
-    private HttpRequestFactory childRequestFactory;
     private JsonFactory jsonFactory;
     private HttpResponseInterceptor responseInterceptor;
 
@@ -162,12 +145,6 @@ Builder setRequestFactory(HttpRequestFactory requestFactory) {
       return this;
     }
 
-    Builder setChildRequestFactory(
-            HttpRequestFactory childRequestFactory) {
-      this.childRequestFactory = childRequestFactory;
-      return this;
-    }
-
     Builder setJsonFactory(JsonFactory jsonFactory) {
       this.jsonFactory = jsonFactory;
       return this;

src/main/java/com/google/firebase/remoteconfig/RemoteConfigTemplate.java

@@ -18,7 +18,7 @@
 
 import com.google.api.client.util.Key;
 
-public class RemoteConfigTemplate {
+public final class RemoteConfigTemplate {
 
   @Key("etag")
   private String etag;

src/main/java/com/google/firebase/remoteconfig/internal/RemoteConfigServiceErrorResponse.java

@@ -30,7 +30,7 @@
  * These error messages take the form,
  * `"error": {"code": 123, "message": "[CODE]: Message Details", "status": "ERROR_STATUS"}`
  */
-public class RemoteConfigServiceErrorResponse extends GenericJson {
+public final class RemoteConfigServiceErrorResponse extends GenericJson {
 
   private static final Map<String, RemoteConfigErrorCode> RC_ERROR_CODES =
           ImmutableMap.<String, RemoteConfigErrorCode>builder()
@@ -55,7 +55,7 @@ public RemoteConfigErrorCode getRemoteConfigErrorCode() {
       return null;
     }
 
-    String message = getErrorMessage();
+    String message = (String) error.get("message");
     if (Strings.isNullOrEmpty(message)) {
       return null;
     }
@@ -68,13 +68,4 @@ public RemoteConfigErrorCode getRemoteConfigErrorCode() {
 
     return null;
   }
-
-  @Nullable
-  public String getErrorMessage() {
-    if (error == null) {
-      return null;
-    }
-
-    return (String) error.get("message");
-  }
 }