Android Question Get push notification from opensource ntfy.sh

/**
 * The broadcast service is responsible for sending and receiving broadcast intents
 * in order to facilitate tasks app integrations.
 */
class BroadcastService(private val ctx: Context) {
    fun sendMessage(subscription: Subscription, notification: Notification, muted: Boolean) {
        val intent = Intent()
        intent.action = MESSAGE_RECEIVED_ACTION
        intent.putExtra("id", notification.id)
        intent.putExtra("base_url", subscription.baseUrl)
        intent.putExtra("topic", subscription.topic)
        intent.putExtra("time", notification.timestamp.toInt())
        intent.putExtra("title", notification.title)
        intent.putExtra("message", decodeMessage(notification))
        intent.putExtra("message_bytes", decodeBytesMessage(notification))
        intent.putExtra("message_encoding", notification.encoding)
        intent.putExtra("tags", notification.tags)
        intent.putExtra("tags_map", joinTagsMap(splitTags(notification.tags)))
        intent.putExtra("priority", notification.priority)
        intent.putExtra("click", notification.click)
        intent.putExtra("muted", muted)
        intent.putExtra("muted_str", muted.toString())
        intent.putExtra("attachment_name", notification.attachment?.name ?: "")
        intent.putExtra("attachment_type", notification.attachment?.type ?: "")
        intent.putExtra("attachment_size", notification.attachment?.size ?: 0L)
        intent.putExtra("attachment_expires", notification.attachment?.expires ?: 0L)
        intent.putExtra("attachment_url", notification.attachment?.url ?: "")

        Log.d(TAG, "Sending message intent broadcast: ${intent.action} with extras ${intent.extras}")
        ctx.sendBroadcast(intent)
    }

    fun sendUserAction(action: Action) {
        val intent = Intent()
        intent.action = action.intent ?: USER_ACTION_ACTION
        action.extras?.forEach { (key, value) ->
            intent.putExtra(key, value)
        }
        Log.d(TAG, "Sending user action intent broadcast: ${intent.action} with extras ${intent.extras}")
        ctx.sendBroadcast(intent)
    }

    /**
     * This receiver is triggered when the SEND_MESSAGE intent is received.
     * See AndroidManifest.xml for details.
     */
    class BroadcastReceiver : android.content.BroadcastReceiver() {
        override fun onReceive(context: Context, intent: Intent) {
            Log.d(TAG, "Broadcast received: $intent")
            when (intent.action) {
                MESSAGE_SEND_ACTION -> send(context, intent)
            }
        }

        private fun send(ctx: Context, intent: Intent) {
            val api = ApiService()
            val baseUrl = getStringExtra(intent, "base_url") ?: ctx.getString(R.string.app_base_url)
            val topic = getStringExtra(intent, "topic") ?: return
            val message = getStringExtra(intent, "message") ?: return
            val title = getStringExtra(intent, "title") ?: ""
            val tags = getStringExtra(intent,"tags") ?: ""
            val priority = when (getStringExtra(intent, "priority")) {
                "min", "1" -> 1
                "low", "2" -> 2
                "default", "3" -> 3
                "high", "4" -> 4
                "urgent", "max", "5" -> 5
                else -> 0
            }
            val delay = getStringExtra(intent,"delay") ?: ""
            GlobalScope.launch(Dispatchers.IO) {
                val repository = Repository.getInstance(ctx)
                val user = repository.getUser(baseUrl) // May be null
                try {
                    Log.d(TAG, "Publishing message $intent")
                    api.publish(
                        baseUrl = baseUrl,
                        topic = topic,
                        user = user,
                        message = message,
                        title = title,
                        priority = priority,
                        tags = splitTags(tags),
                        delay = delay
                    )
                } catch (e: Exception) {
                    Log.w(TAG, "Unable to publish message: ${e.message}", e)
                }
            }
        }

        /**
         * Gets an extra as a String value, even if the extra may be an int or a long.
         */
        private fun getStringExtra(intent: Intent, name: String): String? {
            if (intent.getStringExtra(name) != null) {
                return intent.getStringExtra(name)
            } else if (intent.getIntExtra(name, DOES_NOT_EXIST) != DOES_NOT_EXIST) {
                return intent.getIntExtra(name, DOES_NOT_EXIST).toString()
            } else if (intent.getLongExtra(name, DOES_NOT_EXIST.toLong()) != DOES_NOT_EXIST.toLong()) {
                return intent.getLongExtra(name, DOES_NOT_EXIST.toLong()).toString()
            }
            return null
        }
    }

    companion object {
        private const val TAG = "NtfyBroadcastService"
        private const val DOES_NOT_EXIST = -2586000

        // These constants cannot be changed without breaking the contract; also see manifest
        private const val MESSAGE_RECEIVED_ACTION = "io.heckel.ntfy.MESSAGE_RECEIVED"
        private const val MESSAGE_SEND_ACTION = "io.heckel.ntfy.SEND_MESSAGE"
        private const val USER_ACTION_ACTION = "io.heckel.ntfy.USER_ACTION"
    }
}

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="io.heckel.ntfy">

    <!-- Permissions -->
    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.FOREGROUND_SERVICE"/> <!-- For instant delivery foregrounds service -->
    <uses-permission android:name="android.permission.WAKE_LOCK"/> <!-- To keep foreground service awake; soon not needed anymore -->
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/> <!-- To restart service on reboot -->
    <uses-permission android:name="android.permission.VIBRATE"/> <!-- Incoming notifications should be able to vibrate the phone -->
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" android:maxSdkVersion="28"/> <!-- Only required on SDK <= 28 -->
    <uses-permission android:name="android.permission.SCHEDULE_EXACT_ALARM"/> <!-- To reschedule the websocket retry -->
    <uses-permission android:name="android.permission.POST_NOTIFICATIONS"/> <!-- As of Android 13, we need to ask for permission to post notifications -->

    <!--
        Permission REQUEST_INSTALL_PACKAGES (F-Droid only!):
          - Permission is used to install .apk files that were received as attachments
          - Google rejected the permission for ntfy, so this permission is STRIPPED OUT by the build process
            for the Google Play variant of the app.
    -->
    <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES"/>

    <application
            android:name=".app.Application"
            android:allowBackup="true"
            android:icon="@mipmap/ic_launcher"
            android:label="@string/app_name"
            android:roundIcon="@mipmap/ic_launcher"
            android:supportsRtl="true"
            android:theme="@style/AppTheme"
            android:networkSecurityConfig="@xml/network_security_config"
            android:usesCleartextTraffic="true">

        <!-- Main activity -->
        <activity
                android:name=".ui.MainActivity"
                android:label="@string/app_name"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>

        <!-- Detail activity -->
        <activity
                android:name=".ui.DetailActivity"
                android:parentActivityName=".ui.MainActivity"
                android:exported="true">
            <meta-data
                    android:name="android.support.PARENT_ACTIVITY"
                    android:value=".ui.MainActivity"/>

            <!-- Open ntfy:// links with the app -->
            <intent-filter android:label="@string/app_name">
                <action android:name="android.intent.action.VIEW" />
                <category android:name="android.intent.category.DEFAULT" />
                <category android:name="android.intent.category.BROWSABLE" />
                <data android:scheme="ntfy" />
            </intent-filter>
        </activity>

        <!-- Settings activity -->
        <activity
                android:name=".ui.SettingsActivity"
                android:parentActivityName=".ui.MainActivity">
            <meta-data
                    android:name="android.support.PARENT_ACTIVITY"
                    android:value=".ui.MainActivity"/>
        </activity>

        <!-- Detail settings activity -->
        <activity
                android:name=".ui.DetailSettingsActivity"
                android:parentActivityName=".ui.DetailActivity">
        </activity>

        <!-- Share file activity, incoming files/shares -->
        <activity android:name=".ui.ShareActivity" android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.SEND" />
                <category android:name="android.intent.category.DEFAULT" />
                <data android:mimeType="image/*" />
                <data android:mimeType="text/*" />
                <data android:mimeType="audio/*" />
                <data android:mimeType="video/*" />
                <data android:mimeType="application/*" />
            </intent-filter>
        </activity>

        <!-- Hack: Activity used for "view" action button with "clear=true" (to be able to cancel notifications and show a URL) -->
        <activity
                android:name=".msg.NotificationService$ViewActionWithClearActivity"
                android:exported="false">
        </activity>

        <!-- Subscriber foreground service for hosts other than ntfy.sh -->
        <service android:name=".service.SubscriberService"/>

        <!-- Subscriber service restart on reboot -->
        <receiver
                android:name=".service.SubscriberService$BootStartReceiver"
                android:enabled="true"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.BOOT_COMPLETED"/>
            </intent-filter>
        </receiver>

        <!-- Subscriber service restart on destruction -->
        <receiver
                android:name=".service.SubscriberService$AutoRestartReceiver"
                android:enabled="true"
                android:exported="false"/>

        <!-- Broadcast receiver to send messages via intents -->
        <receiver
                android:name=".msg.BroadcastService$BroadcastReceiver"
                android:enabled="true"
                android:exported="true">
            <intent-filter>
                <action android:name="io.heckel.ntfy.SEND_MESSAGE"/>
            </intent-filter>
        </receiver>

        <!-- Broadcast receiver for UnifiedPush; must match https://github.com/UnifiedPush/UP-spec/blob/main/specifications.md -->
        <receiver
                android:name=".up.BroadcastReceiver"
                android:enabled="true"
                android:exported="true">
            <intent-filter>
                <action android:name="org.unifiedpush.android.distributor.REGISTER"/>
                <action android:name="org.unifiedpush.android.distributor.UNREGISTER"/>
                <action android:name="org.unifiedpush.android.distributor.feature.BYTES_MESSAGE"/>
            </intent-filter>
        </receiver>

        <!-- Broadcast receiver for the "Download"/"Cancel" attachment action in the notification popup -->
        <receiver
                android:name=".msg.NotificationService$UserActionBroadcastReceiver"
                android:enabled="true"
                android:exported="false">
        </receiver>

        <!-- Broadcast receiver for when the notification is swiped away (currently only to cancel the insistent sound) -->
        <receiver
                android:name=".msg.NotificationService$DeleteBroadcastReceiver"
                android:enabled="true"
                android:exported="false">
        </receiver>

        <!-- Firebase messaging (note that this is empty in the F-Droid flavor) -->
        <service
                android:name=".firebase.FirebaseService"
                android:exported="false">
            <intent-filter>
                <action android:name="com.google.firebase.MESSAGING_EVENT"/>
            </intent-filter>
        </service>
        <meta-data
                android:name="firebase_analytics_collection_enabled"
                android:value="false"/>
        <meta-data
                android:name="com.google.firebase.messaging.default_notification_icon"
                android:resource="@drawable/ic_notification"/>

        <!-- FileProvider required for older Android versions (<= P), to allow passing the file URI in the open intent.
             Avoids "exposed beyond app through Intent.getData" exception, see see https://stackoverflow.com/a/57288352/1440785 -->
        <provider
                android:name="androidx.core.content.FileProvider"
                android:authorities="${applicationId}.provider"
                android:exported="false"
                android:grantUriPermissions="true">
            <meta-data
                    android:name="android.support.FILE_PROVIDER_PATHS"
                    android:resource="@xml/file_paths"/>
        </provider>
    </application>
</manifest>