package com.google.firebase.samples.config;
import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.Arrays;
import java.util.Collections;
import java.util.Scanner;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
/**
* Retrieve and publish templates for Firebase Remote Config using the REST API.
*/
public class Configure {
private final static String PROJECT_ID = "PROJECT_ID";
private final static String BASE_URL = "https://firebaseremoteconfig.googleapis.com";
private final static String REMOTE_CONFIG_ENDPOINT = "/v1/projects/" + PROJECT_ID + "/remoteConfig";
private final static String[] SCOPES = { "https://www.googleapis.com/auth/firebase.remoteconfig" };
/**
* Retrieve a valid access token that can be use to authorize requests to the Remote Config REST
* API.
*
* @return Access token.
* @throws IOException
*/
// [START retrieve_access_token]
private static String getAccessToken() throws IOException {
GoogleCredential googleCredential = GoogleCredential
.fromStream(new FileInputStream("service-account.json"))
.createScoped(Arrays.asList(SCOPES));
googleCredential.refreshToken();
return googleCredential.getAccessToken();
}
// [END retrieve_access_token]
/**
* Get current Firebase Remote Config template from server and store it locally.
*
* @throws IOException
*/
private static void getTemplate() throws IOException {
HttpURLConnection httpURLConnection = getCommonConnection(BASE_URL + REMOTE_CONFIG_ENDPOINT);
httpURLConnection.setRequestMethod("GET");
httpURLConnection.setRequestProperty("Accept-Encoding", "gzip");
int code = httpURLConnection.getResponseCode();
if (code == 200) {
InputStream inputStream = new GZIPInputStream(httpURLConnection.getInputStream());
String response = inputstreamToString(inputStream);
JsonParser jsonParser = new JsonParser();
JsonElement jsonElement = jsonParser.parse(response);
Gson gson = new GsonBuilder().setPrettyPrinting().disableHtmlEscaping().create();
String jsonStr = gson.toJson(jsonElement);
File file = new File("config.json");
PrintWriter printWriter = new PrintWriter(new FileWriter(file));
printWriter.print(jsonStr);
printWriter.flush();
printWriter.close();
System.out.println("Template retrieved and has been written to config.json");
// Print ETag
String etag = httpURLConnection.getHeaderField("ETag");
System.out.println("ETag from server: " + etag);
} else {
System.out.println(inputstreamToString(httpURLConnection.getErrorStream()));
}
}
/**
* Print the last 5 available Firebase Remote Config template metadata from the server.
*
* @throws IOException
*/
private static void getVersions() throws IOException {
HttpURLConnection httpURLConnection = getCommonConnection(BASE_URL + REMOTE_CONFIG_ENDPOINT
+ ":listVersions?pageSize=5");
httpURLConnection.setRequestMethod("GET");
int code = httpURLConnection.getResponseCode();
if (code == 200) {
String versions = inputstreamToPrettyString(httpURLConnection.getInputStream());
System.out.println("Versions:");
System.out.println(versions);
} else {
System.out.println(inputstreamToString(httpURLConnection.getErrorStream()));
}
}
/**
* Roll back to an available version of Firebase Remote Config template.
*
* @param version The version to roll back to.
*
* @throws IOException
*/
private static void rollback(int version) throws IOException {
HttpURLConnection httpURLConnection = getCommonConnection(BASE_URL + REMOTE_CONFIG_ENDPOINT
+ ":rollback");
httpURLConnection.setDoOutput(true);
httpURLConnection.setRequestMethod("POST");
httpURLConnection.setRequestProperty("Accept-Encoding", "gzip");
JsonObject jsonObject = new JsonObject();
jsonObject.addProperty("version_number", version);
OutputStreamWriter outputStreamWriter = new OutputStreamWriter(httpURLConnection.getOutputStream());
outputStreamWriter.write(jsonObject.toString());
outputStreamWriter.flush();
outputStreamWriter.close();
int code = httpURLConnection.getResponseCode();
if (code == 200) {
System.out.println("Rolled back to: " + version);
InputStream inputStream = new GZIPInputStream(httpURLConnection.getInputStream());
System.out.println(inputstreamToPrettyString(inputStream));
// Print ETag
String etag = httpURLConnection.getHeaderField("ETag");
System.out.println("ETag from server: " + etag);
} else {
System.out.println("Error:");
InputStream inputStream = new GZIPInputStream(httpURLConnection.getErrorStream());
System.out.println(inputstreamToString(inputStream));
}
}
/**
* Publish local template to Firebase server.
*
* @throws IOException
*/
private static void publishTemplate(String etag) throws IOException {
if (etag.equals("*")) {
Scanner scanner = new Scanner(System.in);
System.out.println("Are you sure you would like to force replace the template? Yes (y), No (n)");
String answer = scanner.nextLine();
if (!answer.equalsIgnoreCase("y")) {
System.out.println("Publish canceled.");
return;
}
}
System.out.println("Publishing template...");
HttpURLConnection httpURLConnection = getCommonConnection(BASE_URL + REMOTE_CONFIG_ENDPOINT);
httpURLConnection.setDoOutput(true);
httpURLConnection.setRequestMethod("PUT");
httpURLConnection.setRequestProperty("If-Match", etag);
httpURLConnection.setRequestProperty("Content-Encoding", "gzip");
String configStr = readConfig();
GZIPOutputStream gzipOutputStream = new GZIPOutputStream(httpURLConnection.getOutputStream());
OutputStreamWriter outputStreamWriter = new OutputStreamWriter(gzipOutputStream);
outputStreamWriter.write(configStr);
outputStreamWriter.flush();
outputStreamWriter.close();
int code = httpURLConnection.getResponseCode();
if (code == 200) {
System.out.println("Template has been published.");
} else {
System.out.println(inputstreamToString(httpURLConnection.getErrorStream()));
}
}
/**
* Read the Firebase Remote Config template from config.json file.
*
* @return String with contents of config.json file.
* @throws FileNotFoundException
*/
private static String readConfig() throws FileNotFoundException {
File file = new File("config.json");
Scanner scanner = new Scanner(file);
StringBuilder stringBuilder = new StringBuilder();
while (scanner.hasNext()) {
stringBuilder.append(scanner.nextLine());
}
return stringBuilder.toString();
}
/**
* Format content from an InputStream as pretty JSON.
*
* @param inputStream Content to be formatted.
* @return Pretty JSON formatted string.
*
* @throws IOException
*/
private static String inputstreamToPrettyString(InputStream inputStream) throws IOException {
String response = inputstreamToString(inputStream);
JsonParser jsonParser = new JsonParser();
JsonElement jsonElement = jsonParser.parse(response);
Gson gson = new GsonBuilder().setPrettyPrinting().disableHtmlEscaping().create();
String jsonStr = gson.toJson(jsonElement);
return jsonStr;
}
/**
* Read contents of InputStream into String.
*
* @param inputStream InputStream to read.
* @return String containing contents of InputStream.
* @throws IOException
*/
private static String inputstreamToString(InputStream inputStream) throws IOException {
StringBuilder stringBuilder = new StringBuilder();
Scanner scanner = new Scanner(inputStream);
while (scanner.hasNext()) {
stringBuilder.append(scanner.nextLine());
}
return stringBuilder.toString();
}
/**
* Create HttpURLConnection that can be used for both retrieving and publishing.
*
* @return Base HttpURLConnection.
* @throws IOException
*/
private static HttpURLConnection getCommonConnection(String endpoint) throws IOException {
URL url = new URL(endpoint);
HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
httpURLConnection.setRequestProperty("Authorization", "Bearer " + getAccessToken());
httpURLConnection.setRequestProperty("Content-Type", "application/json; UTF-8");
return httpURLConnection;
}
public static void main(String[] args) throws IOException {
if (args.length > 1 && args[0].equals("publish")) {
publishTemplate(args[1]);
} else if (args.length == 1 && args[0].equals("get")) {
getTemplate();
} else if (args.length == 1 && args[0].equals("versions")) {
getVersions();
} else if (args.length > 1 && args[0].equals("rollback")) {
rollback(Integer.parseInt(args[1]));
} else {
System.err.println("Invalid request. Please use one of the following commands:");
// To get the current template from the server.
System.err.println("./gradlew run -Paction=get");
// To publish the template in config.json to the server.
System.err.println("./gradlew run -Paction=publish -Petag='<LATEST_ETAG>'");
// To get the available template versions from the server.
System.err.println("./gradlew run -Paction=versions");
// To roll back to a particular version.
System.err.println("./gradlew run -Paction=rollback -Pversion=<TEMPLATE_VERSION_NUMBER>");
}
}
}
