Add improvements to Google API token generation in FCM

components/device-mgt-extensions/io.entgra.device.mgt.core.device.mgt.extensions.push.notification.provider.fcm/pom.xml

@@ -111,6 +111,46 @@
             <groupId>org.wso2.carbon.analytics-common</groupId>
             <artifactId>org.wso2.carbon.event.output.adapter.core</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.wso2.orbit.com.google.http-client</groupId>
+            <artifactId>google-http-client</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.wso2.orbit.com.google.auth-library-oauth2-http</groupId>
+            <artifactId>google-auth-library-oauth2-http</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.wso2.orbit.io.opencensus</groupId>
+            <artifactId>opencensus</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.opencensus</groupId>
+            <artifactId>opencensus-api</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>io.opencensus</groupId>
+            <artifactId>opencensus-contrib-http-util</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.wso2.orbit.io.grpc</groupId>
+            <artifactId>grpc-context</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.google.http-client</groupId>
+            <artifactId>google-http-client-gson</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.google.guava</groupId>
+            <artifactId>failureaccess</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.google.guava</groupId>
+            <artifactId>guava</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.wso2.carbon</groupId>
+            <artifactId>org.wso2.carbon.utils</artifactId>
+        </dependency>
     </dependencies>
 
     <build>
@@ -137,12 +177,27 @@
                             com.google.gson,
                             org.osgi.framework.*;version="${imp.package.version.osgi.framework}",
                             org.osgi.service.*;version="${imp.package.version.osgi.service}",
+                            org.wso2.carbon.utils.*,
                             io.entgra.device.mgt.core.device.mgt.common.operation.mgt,
                             io.entgra.device.mgt.core.device.mgt.common.push.notification,
                             org.apache.commons.logging,
                             io.entgra.device.mgt.core.device.mgt.common.*,
-                            io.entgra.device.mgt.core.device.mgt.core.service
+                            io.entgra.device.mgt.core.device.mgt.core.service,
+                            io.entgra.device.mgt.core.device.mgt.core.config.*,
+                            io.entgra.device.mgt.core.device.mgt.core.config.push.notification.*,
+                            io.entgra.device.mgt.core.device.mgt.extensions.logger.spi,
+                            io.entgra.device.mgt.core.notification.logger.*,
+                            com.google.auth.oauth2.*
                         </Import-Package>
+                        <Embed-Dependency>
+                            google-auth-library-oauth2-http;scope=compile|runtime,
+                            google-http-client;scope=compile|runtime,
+                            grpc-context;scope=compile|runtime,
+                            guava;scope=compile|runtime,
+                            opencensus;scope=compile|runtime,
+                            failureaccess;scope=compile|runtime
+                        </Embed-Dependency>
+                        <Embed-Transitive>true</Embed-Transitive>
                     </instructions>
                 </configuration>
             </plugin>

components/device-mgt-extensions/io.entgra.device.mgt.core.device.mgt.extensions.push.notification.provider.fcm/src/main/java/io/entgra/device/mgt/core/device/mgt/extensions/push/notification/provider/fcm/FCMBasedPushNotificationProvider.java

@@ -32,7 +32,9 @@ public class FCMBasedPushNotificationProvider implements PushNotificationProvide
 
     @Override
     public NotificationStrategy getNotificationStrategy(PushNotificationConfig config) {
-        return new FCMNotificationStrategy(config);
+        FCMNotificationStrategy fcmNotificationStrategy = new FCMNotificationStrategy(config);
+        fcmNotificationStrategy.init();
+        return fcmNotificationStrategy;
     }
 
 }

components/device-mgt-extensions/io.entgra.device.mgt.core.device.mgt.extensions.push.notification.provider.fcm/src/main/java/io/entgra/device/mgt/core/device/mgt/extensions/push/notification/provider/fcm/FCMNotificationStrategy.java

@@ -17,9 +17,12 @@
  */
 package io.entgra.device.mgt.core.device.mgt.extensions.push.notification.provider.fcm;
 
-import com.google.gson.JsonArray;
+import com.google.auth.oauth2.GoogleCredentials;
 import com.google.gson.JsonObject;
-import com.google.gson.JsonPrimitive;
+import io.entgra.device.mgt.core.device.mgt.core.config.DeviceConfigurationManager;
+import io.entgra.device.mgt.core.device.mgt.core.config.push.notification.ContextMetadata;
+import io.entgra.device.mgt.core.device.mgt.core.config.push.notification.PushNotificationConfiguration;
+import io.entgra.device.mgt.core.device.mgt.extensions.push.notification.provider.fcm.util.FCMUtil;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import io.entgra.device.mgt.core.device.mgt.common.Device;
@@ -29,24 +32,29 @@ import io.entgra.device.mgt.core.device.mgt.common.push.notification.Notificatio
 import io.entgra.device.mgt.core.device.mgt.common.push.notification.PushNotificationConfig;
 import io.entgra.device.mgt.core.device.mgt.common.push.notification.PushNotificationExecutionFailedException;
 import io.entgra.device.mgt.core.device.mgt.extensions.push.notification.provider.fcm.internal.FCMDataHolder;
+import org.wso2.carbon.utils.CarbonUtils;
 
+import java.io.File;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.net.HttpURLConnection;
 import java.net.URL;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.util.List;
+import java.util.Properties;
 
 public class FCMNotificationStrategy implements NotificationStrategy {
 
     private static final Log log = LogFactory.getLog(FCMNotificationStrategy.class);
-
     private static final String NOTIFIER_TYPE_FCM = "FCM";
     private static final String FCM_TOKEN = "FCM_TOKEN";
-    private static final String FCM_ENDPOINT = "https://fcm.googleapis.com/fcm/send";
     private static final String FCM_API_KEY = "fcmAPIKey";
-    private static final int TIME_TO_LIVE = 2419199; // 1 second less that 28 days
+    private static final int TIME_TO_LIVE = 2419199; // 1 second less than 28 days
     private static final int HTTP_STATUS_CODE_OK = 200;
     private final PushNotificationConfig config;
+    private static final String FCM_ENDPOINT_KEY = "FCM_SERVER_ENDPOINT";
 
     public FCMNotificationStrategy(PushNotificationConfig config) {
         this.config = config;
@@ -64,12 +72,14 @@ public class FCMNotificationStrategy implements NotificationStrategy {
                 Device device = FCMDataHolder.getInstance().getDeviceManagementProviderService()
                         .getDeviceWithTypeProperties(ctx.getDeviceId());
                 if(device.getProperties() != null && getFCMToken(device.getProperties()) != null) {
-                    this.sendWakeUpCall(ctx.getOperation().getCode(), device);
+                    FCMUtil.getInstance().getDefaultApplication().refresh();
+                    sendWakeUpCall(FCMUtil.getInstance().getDefaultApplication().getAccessToken().getTokenValue(),
+                            getFCMToken(device.getProperties()));
                 }
             } else {
                 if (log.isDebugEnabled()) {
                     log.debug("Not using FCM notifier as notifier type is set to " + config.getType() +
-                              " in Platform Configurations.");
+                            " in Platform Configurations.");
                 }
             }
         } catch (DeviceManagementException e) {
@@ -79,71 +89,66 @@ public class FCMNotificationStrategy implements NotificationStrategy {
         }
     }
 
-    @Override
-    public NotificationContext buildContext() {
-        return null;
-    }
 
-    @Override
-    public void undeploy() {
 
-    }
+    private void sendWakeUpCall(String accessToken, String registrationId) throws IOException,
+            PushNotificationExecutionFailedException {
+        OutputStream os = null;
+        HttpURLConnection conn = null;
+
+        String fcmServerEndpoint = FCMUtil.getInstance().getContextMetadataProperties().getProperty(FCM_ENDPOINT_KEY);
+        if(fcmServerEndpoint == null) {
+            String msg = "Encountered configuration issue. " + FCM_ENDPOINT_KEY + " is not defined";
+            log.error(msg);
+            throw new PushNotificationExecutionFailedException(msg);
+        }
+
+        try {
+            byte[] bytes = getFCMRequest(registrationId).getBytes();
+            URL url = new URL(fcmServerEndpoint);
+            conn = (HttpURLConnection) url.openConnection();
+            conn.setRequestProperty("Content-Type", "application/json");
+            conn.setRequestProperty("Authorization", "Bearer " + accessToken);
+            conn.setRequestMethod("POST");
+            conn.setDoOutput(true);
+
+            os = conn.getOutputStream();
+            os.write(bytes);
 
-    private void sendWakeUpCall(String message, Device device) throws IOException,
-                                                                      PushNotificationExecutionFailedException {
-        if (device.getProperties() != null) {
-            OutputStream os = null;
-            byte[] bytes = getFCMRequest(message, getFCMToken(device.getProperties())).getBytes();
-
-            HttpURLConnection conn = null;
-            try {
-                conn = (HttpURLConnection) new URL(FCM_ENDPOINT).openConnection();
-                conn.setRequestProperty("Content-Type", "application/json");
-                conn.setRequestProperty("Authorization", "key=" + config.getProperty(FCM_API_KEY));
-                conn.setRequestMethod("POST");
-                conn.setDoOutput(true);
-                os = conn.getOutputStream();
-                os.write(bytes);
-            } finally {
-                if (os != null) {
-                    os.close();
-                }
-                if (conn != null) {
-                    conn.disconnect();
-                }
-            }
             int status = conn.getResponseCode();
-            if (log.isDebugEnabled()) {
-                log.debug("Result code: " + status + ", Message: " + conn.getResponseMessage());
+            if (status != 200) {
+                log.error("Response Status: " + status + ", Response Message: " + conn.getResponseMessage());
             }
-            if (status != HTTP_STATUS_CODE_OK) {
-                throw new PushNotificationExecutionFailedException("Push notification sending failed with the HTTP " +
-                        "error code '" + status + "'");
+        } finally {
+            if (os != null) {
+                os.close();
+            }
+            if (conn != null) {
+                conn.disconnect();
             }
         }
     }
 
-    private static String getFCMRequest(String message, String registrationId) {
-        JsonObject fcmRequest = new JsonObject();
-        fcmRequest.addProperty("delay_while_idle", false);
-        fcmRequest.addProperty("time_to_live", TIME_TO_LIVE);
-        fcmRequest.addProperty("priority", "high");
-
-        //Add message to FCM request
-        JsonObject data = new JsonObject();
-        if (message != null && !message.isEmpty()) {
-            data.addProperty("data", message);
-            fcmRequest.add("data", data);
-        }
+    private static String getFCMRequest(String registrationId) {
+        JsonObject messageObject = new JsonObject();
+        messageObject.addProperty("token", registrationId);
 
-        //Set device reg-id
-        JsonArray regIds = new JsonArray();
-        regIds.add(new JsonPrimitive(registrationId));
+        JsonObject fcmRequest = new JsonObject();
+        fcmRequest.add("message", messageObject);
 
-        fcmRequest.add("registration_ids", regIds);
         return fcmRequest.toString();
     }
 
+    @Override
+    public NotificationContext buildContext() {
+        return null;
+    }
+
+    @Override
+    public void undeploy() {
+
+    }
+
     private static String getFCMToken(List<Device.Property> properties) {
         String fcmToken = null;
         for (Device.Property property : properties) {
@@ -159,5 +164,4 @@ public class FCMNotificationStrategy implements NotificationStrategy {
     public PushNotificationConfig getConfig() {
         return config;
     }
-
 }

components/device-mgt-extensions/io.entgra.device.mgt.core.device.mgt.extensions.push.notification.provider.fcm/src/main/java/io/entgra/device/mgt/core/device/mgt/extensions/push/notification/provider/fcm/util/FCMUtil.java

@@ -0,0 +1,80 @@
+package io.entgra.device.mgt.core.device.mgt.extensions.push.notification.provider.fcm.util;
+
+import com.google.auth.oauth2.GoogleCredentials;
+import io.entgra.device.mgt.core.device.mgt.core.config.DeviceConfigurationManager;
+import io.entgra.device.mgt.core.device.mgt.core.config.push.notification.ContextMetadata;
+import io.entgra.device.mgt.core.device.mgt.core.config.push.notification.PushNotificationConfiguration;
+import io.entgra.device.mgt.core.device.mgt.extensions.push.notification.provider.fcm.FCMNotificationStrategy;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.wso2.carbon.utils.CarbonUtils;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.List;
+import java.util.Properties;
+
+public class FCMUtil {
+
+    private static final Log log = LogFactory.getLog(FCMUtil.class);
+    private static volatile FCMUtil instance;
+    private static GoogleCredentials defaultApplication;
+    private static final String FCM_SERVICE_ACCOUNT_PATH = CarbonUtils.getCarbonHome() + File.separator +
+            "repository" + File.separator + "resources" + File.separator + "service-account.json";
+    private static final String[] FCM_SCOPES = { "https://www.googleapis.com/auth/firebase.messaging" };
+    private Properties contextMetadataProperties;
+
+    private FCMUtil() {
+        initContextConfigs();
+        initDefaultOAuthApplication();
+    }
+
+    private void initDefaultOAuthApplication() {
+        if (defaultApplication == null) {
+            Path serviceAccountPath = Paths.get(FCM_SERVICE_ACCOUNT_PATH);
+            try {
+                defaultApplication = GoogleCredentials.
+                        fromStream(Files.newInputStream(serviceAccountPath)).
+                        createScoped(FCM_SCOPES);
+            } catch (IOException e) {
+                log.error("Fail to initialize default OAuth application for FCM communication");
+                throw new IllegalStateException(e);
+            }
+        }
+    }
+
+    private void initContextConfigs() {
+        PushNotificationConfiguration pushNotificationConfiguration = DeviceConfigurationManager.getInstance().
+                getDeviceManagementConfig().getPushNotificationConfiguration();
+        List<ContextMetadata> contextMetadata = pushNotificationConfiguration.getContextMetadata();
+        Properties properties = new Properties();
+        if (contextMetadata != null) {
+            for (ContextMetadata metadata : contextMetadata) {
+                properties.setProperty(metadata.getKey(), metadata.getValue());
+            }
+        }
+        contextMetadataProperties = properties;
+    }
+
+    public static FCMUtil getInstance() {
+        if (instance == null) {
+            synchronized (FCMUtil.class) {
+                if (instance == null) {
+                    instance = new FCMUtil();
+                }
+            }
+        }
+        return instance;
+    }
+
+    public GoogleCredentials getDefaultApplication() {
+        return defaultApplication;
+    }
+
+    public Properties getContextMetadataProperties() {
+        return contextMetadataProperties;
+    }
+}

components/device-mgt/io.entgra.device.mgt.core.device.mgt.core/src/main/java/io/entgra/device/mgt/core/device/mgt/core/config/push/notification/ContextMetadata.java

@@ -0,0 +1,30 @@
+package io.entgra.device.mgt.core.device.mgt.core.config.push.notification;
+
+import javax.xml.bind.annotation.XmlAttribute;
+import javax.xml.bind.annotation.XmlElement;
+import javax.xml.bind.annotation.XmlRootElement;
+import javax.xml.bind.annotation.XmlValue;
+
+@XmlRootElement(name = "ContextMetadata")
+public class ContextMetadata {
+    private String key;
+    private String value;
+
+    @XmlAttribute(name = "key")
+    public String getKey() {
+        return key;
+    }
+
+    public void setKey(String key) {
+        this.key = key;
+    }
+
+    @XmlValue
+    public String getValue() {
+        return value;
+    }
+
+    public void setValue(String value) {
+        this.value = value;
+    }
+}

components/device-mgt/io.entgra.device.mgt.core.device.mgt.core/src/main/java/io/entgra/device/mgt/core/device/mgt/core/config/push/notification/PushNotificationConfiguration.java

@@ -33,6 +33,7 @@ public class PushNotificationConfiguration {
     private int schedulerTaskInitialDelay;
     private boolean schedulerTaskEnabled;
     private List<String> pushNotificationProviders;
+    private List<ContextMetadata> contextMetadata;
 
     @XmlElement(name = "SchedulerBatchSize", required = true)
     public int getSchedulerBatchSize() {
@@ -79,4 +80,14 @@ public class PushNotificationConfiguration {
     public void setPushNotificationProviders(List<String> pushNotificationProviders) {
         this.pushNotificationProviders = pushNotificationProviders;
     }
+
+    @XmlElementWrapper(name = "ProviderContextMetadata")
+    @XmlElement(name = "ContextMetadata", required = true)
+    public List<ContextMetadata> getContextMetadata() {
+        return contextMetadata;
+    }
+
+    public void setContextMetadata(List<ContextMetadata> contextMetadata) {
+        this.contextMetadata = contextMetadata;
+    }
 }

features/device-mgt/io.entgra.device.mgt.core.device.mgt.basics.feature/src/main/resources/conf_templates/templates/repository/conf/cdm-config.xml.j2

@@ -48,6 +48,11 @@
             {% endfor %}
         {% endif %}
         </PushNotificationProviders>
+        {% if device_mgt_conf.push_notification_conf.fcm_server_endpoint is defined %}
+            <ProviderContextMetadata>
+                <ContextMetadata key="FCM_SERVER_ENDPOINT">{{device_mgt_conf.push_notification_conf.fcm_server_endpoint}}</ContextMetadata>
+            </ProviderContextMetadata>
+        {% endif %}
     </PushNotificationConfiguration>
     <PullNotificationConfiguration>
         {% if device_mgt_conf.pull_notification_conf is defined %}

pom.xml

@@ -386,26 +386,11 @@
             </dependency>
             <!-- End of Operation Template Management dependencies -->
 
-            <!-- Conditional Email Access Management dependencies -->
             <dependency>
-                <groupId>io.entgra.device.mgt.core</groupId>
-                <artifactId>io.entgra.device.mgt.core.cea.mgt.common</artifactId>
-                <version>${io.entgra.device.mgt.core.version}</version>
+                <groupId>org.wso2.orbit.com.google.auth-library-oauth2-http</groupId>
+                <artifactId>google-auth-library-oauth2-http</artifactId>
+                <version>1.20.0.wso2v1</version>
             </dependency>
-
-            <dependency>
-                <groupId>io.entgra.device.mgt.core</groupId>
-                <artifactId>io.entgra.device.mgt.core.cea.mgt.core</artifactId>
-                <version>${io.entgra.device.mgt.core.version}</version>
-            </dependency>
-
-            <dependency>
-                <groupId>io.entgra.device.mgt.core</groupId>
-                <artifactId>io.entgra.device.mgt.core.cea.mgt.enforce</artifactId>
-                <version>${io.entgra.device.mgt.core.version}</version>
-            </dependency>
-            <!-- End of Conditional Email Access dependencies -->
-
             <!-- Governance dependencies -->
             <dependency>
                 <groupId>org.wso2.carbon</groupId>
@@ -1916,6 +1901,51 @@
                 <artifactId>mockito-inline</artifactId>
                 <version>${mokito.version}</version>
             </dependency>
+            <dependency>
+                <groupId>com.google.auth</groupId>
+                <artifactId>google-auth-library-oauth2-http</artifactId>
+                <version>1.20.0</version>
+            </dependency>
+            <dependency>
+                <groupId>org.wso2.orbit.com.google.http-client</groupId>
+                <artifactId>google-http-client</artifactId>
+                <version>${com.google.http.client.version}</version>
+            </dependency>
+            <dependency>
+                <groupId>org.wso2.orbit.com.google.auth-library-oauth2-http</groupId>
+                <artifactId>google-auth-library-oauth2-http</artifactId>
+                <version>${com.google.auth.library.auth2.http.version}</version>
+            </dependency>
+            <dependency>
+                <groupId>org.wso2.orbit.io.opencensus</groupId>
+                <artifactId>opencensus</artifactId>
+                <version>${io.opencensus.version}</version>
+            </dependency>
+            <dependency>
+                <groupId>io.opencensus</groupId>
+                <artifactId>opencensus-api</artifactId>
+                <version>${io.opencensus.api.version}</version>
+            </dependency>
+            <dependency>
+                <groupId>io.opencensus</groupId>
+                <artifactId>opencensus-contrib-http-util</artifactId>
+                <version>${io.opencensus.contrib.http.util.version}</version>
+            </dependency>
+            <dependency>
+                <groupId>org.wso2.orbit.io.grpc</groupId>
+                <artifactId>grpc-context</artifactId>
+                <version>${io.grpc.context.version}</version>
+            </dependency>
+            <dependency>
+                <groupId>com.google.http-client</groupId>
+                <artifactId>google-http-client-gson</artifactId>
+                <version>${com.google.http.client.gson.version}</version>
+            </dependency>
+            <dependency>
+                <groupId>com.google.guava</groupId>
+                <artifactId>failureaccess</artifactId>
+                <version>${com.google.failureaccess.version}</version>
+            </dependency>
         </dependencies>
     </dependencyManagement>
 
@@ -2306,6 +2336,15 @@
         <org.wso2.apache.httpcomponents.httpclient.version>4.3.1.wso2v1</org.wso2.apache.httpcomponents.httpclient.version>
         <orbit.h2.version>1.4.199.wso2v1</orbit.h2.version>
         <securevault.version>1.1.3</securevault.version>
+
+        <com.google.auth.library.auth2.http.version>1.20.0.wso2v1</com.google.auth.library.auth2.http.version>
+        <com.google.http.client.version>1.41.2.wso2v2</com.google.http.client.version>
+        <com.google.failureaccess.version>1.0.1</com.google.failureaccess.version>
+        <com.google.http.client.gson.version>1.43.3</com.google.http.client.gson.version>
+        <io.grpc.context.version>1.27.2.wso2v1</io.grpc.context.version>
+        <io.opencensus.version>0.30.0.wso2v1</io.opencensus.version>
+        <io.opencensus.api.version>0.30.0</io.opencensus.api.version>
+        <io.opencensus.contrib.http.util.version>0.30.0</io.opencensus.contrib.http.util.version>
     </properties>
 
     <pluginRepositories>