check buffering events (#952)

* check buffering events
* use the claim permanent url for buffer events
* update request parameters
* hash user ids for buffer events
* update buffer event endpoint

app/src/main/java/io/lbry/browser/tasks/BufferEventTask.java

@@ -0,0 +1,65 @@
+package io.lbry.browser.tasks;
+
+import android.os.AsyncTask;
+import android.util.Log;
+
+import org.json.JSONObject;
+
+import java.util.concurrent.TimeUnit;
+
+import io.lbry.browser.utils.Helper;
+import okhttp3.OkHttpClient;
+import okhttp3.Request;
+import okhttp3.RequestBody;
+import okhttp3.Response;
+
+public class BufferEventTask extends AsyncTask<Void, Void, Void> {
+    private static final String TAG = "LbryBufferEvent";
+    private static final String ENDPOINT = "https://collector-service.api.lbry.tv/api/v1/events/video";
+
+    private String streamUrl;
+    private String userIdHash;
+    private long streamDuration;
+    private long streamPosition;
+    private long bufferDuration;
+
+    public BufferEventTask(String streamUrl, long streamDuration, long streamPosition, long bufferDuration, String userIdHash) {
+        this.streamUrl = streamUrl;
+        this.bufferDuration = bufferDuration;
+        this.streamDuration = streamDuration;
+        this.streamPosition = streamPosition;
+        this.userIdHash = userIdHash;
+    }
+
+    protected Void doInBackground(Void... params) {
+        JSONObject requestBody = new JSONObject();
+        JSONObject data = new JSONObject();
+        try {
+            data.put("url", streamUrl);
+            data.put("position", streamPosition);
+            data.put("stream_duration", streamDuration);
+            data.put("duration", bufferDuration);
+
+            requestBody.put("device", "android");
+            requestBody.put("type", "buffering");
+            requestBody.put("client", userIdHash);
+            requestBody.put("data", data);
+
+            RequestBody body = RequestBody.create(requestBody.toString(), Helper.JSON_MEDIA_TYPE);
+            Request request =  new Request.Builder().url(ENDPOINT).post(body).build();
+            OkHttpClient client = new OkHttpClient.Builder().
+                    writeTimeout(60, TimeUnit.SECONDS).
+                    readTimeout(60, TimeUnit.SECONDS).
+                    build();
+
+            Response response = client.newCall(request).execute();
+            String responseString = response.body().string();
+            Log.d(TAG, String.format("buffer event sent: %s", responseString));
+        } catch (Exception ex) {
+            // we don't want to fail if a buffer event fails to register
+            Log.d(TAG, String.format("buffer event log failed: %s", ex.getMessage()), ex);
+        }
+
+        return null;
+    }
+}

app/src/main/java/io/lbry/browser/ui/findcontent/FileViewFragment.java

@@ -120,6 +120,7 @@ import io.lbry.browser.model.UrlSuggestion;
 import io.lbry.browser.model.WalletBalance;
 import io.lbry.browser.model.lbryinc.Reward;
 import io.lbry.browser.model.lbryinc.Subscription;
+import io.lbry.browser.tasks.BufferEventTask;
 import io.lbry.browser.tasks.CommentCreateWithTipTask;
 import io.lbry.browser.tasks.CommentListHandler;
 import io.lbry.browser.tasks.CommentListTask;
@@ -165,6 +166,7 @@ public class FileViewFragment extends BaseFragment implements
         WalletBalanceListener {
     private static final int RELATED_CONTENT_SIZE = 16;
     private static final String DEFAULT_PLAYBACK_SPEED = "1x";
+    private static final String CDN_PREFIX = "https://cdn.lbryplayer.xyz";
 
     private PlayerControlView castControlView;
     private Player currentPlayer;
@@ -292,6 +294,27 @@ public class FileViewFragment extends BaseFragment implements
                         loadingNewClaim = false;
                     }
                 } else if (playbackState == Player.STATE_BUFFERING) {
+                    if (MainActivity.appPlayer != null && MainActivity.appPlayer.getCurrentPosition() > 0) {
+                        // we only want to log a buffer event after the media has already started playing
+                        String mediaSourceUrl = getStreamingUrl();
+                        long duration = MainActivity.appPlayer.getDuration();
+                        long position = MainActivity.appPlayer.getCurrentPosition();
+                        // TODO: Determine a hash for the userId
+                        String userIdHash = Helper.SHA256(Lbryio.currentUser != null ? String.valueOf(Lbryio.currentUser.getId()) : "0");
+                        if (mediaSourceUrl.startsWith(CDN_PREFIX)) {
+                            BufferEventTask bufferEvent = new BufferEventTask(claim.getPermanentUrl(), duration, position, 1, userIdHash);
+                            bufferEvent.executeOnExecutor(AsyncTask.SERIAL_EXECUTOR);
+                        } else {
+                            // sdk stream buffer events should be handled differently
+                            Bundle bundle = new Bundle();
+                            bundle.putString("url", claim.getPermanentUrl());
+                            bundle.putLong("stream_duration", duration);
+                            bundle.putLong("stream_position", position);
+                            bundle.putString("user_id_hash", userIdHash);
+                            LbryAnalytics.logEvent(LbryAnalytics.EVENT_BUFFER, bundle);
+                        }
+                    }
+
                     showBuffering();
                 } else {
                     hideBuffering();

app/src/main/java/io/lbry/browser/utils/Helper.java

@@ -30,6 +30,8 @@ import androidx.recyclerview.widget.GridLayoutManager;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
 
+import com.google.android.gms.common.util.Hex;
+
 import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
@@ -37,6 +39,9 @@ import org.json.JSONObject;
 import java.io.Closeable;
 import java.io.File;
 import java.io.IOException;
+import java.io.UnsupportedEncodingException;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
 import java.text.DecimalFormat;
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
@@ -766,4 +771,14 @@ public final class Helper {
         }
         return id.toString();
     }
+
+    public static String SHA256(String value) {
+        try {
+            MessageDigest digest = MessageDigest.getInstance("SHA-256");
+            byte[] hash = digest.digest(value.getBytes("UTF-8"));
+            return Hex.bytesToStringLowercase(hash);
+        } catch (NoSuchAlgorithmException | UnsupportedEncodingException ex) {
+            return null;
+        }
+    }
 }

app/src/main/java/io/lbry/browser/utils/LbryAnalytics.java

@@ -11,6 +11,7 @@ public class LbryAnalytics {
     public static final String EVENT_APP_ERROR = "app_error";
     public static final String EVENT_APP_LAUNCH = "app_launch";
     public static final String EVENT_COMMENT_CREATE = "comment_create";
+    public static final String EVENT_BUFFER  = "buffer";
     public static final String EVENT_EMAIL_ADDED = "email_added";
     public static final String EVENT_EMAIL_VERIFIED = "email_verified";
     public static final String EVENT_FIRST_RUN_COMPLETED = "first_run_completed";