Add Firestore bundles snippets (#286)

Author: samtstern

firestore/app/src/main/java/com/google/example/firestore/SolutionBundles.java

@@ -0,0 +1,85 @@
+package com.google.example.firestore;
+
+import android.util.Log;
+
+import androidx.annotation.NonNull;
+
+import com.google.android.gms.tasks.Continuation;
+import com.google.android.gms.tasks.OnCompleteListener;
+import com.google.android.gms.tasks.Task;
+import com.google.firebase.firestore.FirebaseFirestore;
+import com.google.firebase.firestore.LoadBundleTask;
+import com.google.firebase.firestore.LoadBundleTaskProgress;
+import com.google.firebase.firestore.Query;
+import com.google.firebase.firestore.QuerySnapshot;
+import com.google.firebase.firestore.Source;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.HttpURLConnection;
+import java.net.URL;
+
+/**
+ * https://firebase.google.com/docs/firestore/solutions/serve-bundles
+ */
+public class SolutionBundles {
+
+    private static final String TAG = "SolutionBundles";
+
+    private FirebaseFirestore db;
+
+    // [START fs_bundle_load]
+    public InputStream getBundleStream(String urlString) throws IOException {
+        URL url = new URL(urlString);
+        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
+        return connection.getInputStream();
+    }
+
+    public void fetchBunldeFrom() throws IOException {
+        final InputStream bundleStream = getBundleStream("https://example.com/createBundle");
+        LoadBundleTask loadTask = db.loadBundle(bundleStream);
+
+        // Chain the following tasks
+        // 1) Load the bundle
+        // 2) Get the named query from the local cache
+        // 3) Execute a get() on the named query
+        loadTask.continueWithTask(new Continuation<LoadBundleTaskProgress, Task<Query>>() {
+            @Override
+            public Task<Query> then(@NonNull Task<LoadBundleTaskProgress> task) throws Exception {
+                // Close the stream
+                bundleStream.close();
+
+                // Calling getResult() propagates errors
+                LoadBundleTaskProgress progress = task.getResult(Exception.class);
+
+                // Get the named query from the bundle cache
+                return db.getNamedQuery("latest-stories-query");
+            }
+        }).continueWithTask(new Continuation<Query, Task<QuerySnapshot>>() {
+            @Override
+            public Task<QuerySnapshot> then(@NonNull Task<Query> task) throws Exception {
+                Query query = task.getResult(Exception.class);
+
+                // get() the query results from the cache
+                return query.get(Source.CACHE);
+            }
+        }).addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
+            @Override
+            public void onComplete(@NonNull Task<QuerySnapshot> task) {
+                if (!task.isSuccessful()) {
+                    Log.w(TAG, "Bundle loading failed", task.getException());
+                    return;
+                }
+
+                // Get the QuerySnapshot from the bundle
+                QuerySnapshot storiesSnap = task.getResult();
+
+                // Use the results
+                // ...
+            }
+        });
+    }
+    // [END fs_bundle_load]
+
+}
+

firestore/app/src/main/java/com/google/example/firestore/kotlin/SolutionBundles.kt

@@ -0,0 +1,67 @@
+package com.google.example.firestore.kotlin
+
+import android.util.Log
+import com.google.firebase.firestore.FirebaseFirestore
+import com.google.firebase.firestore.Query
+import com.google.firebase.firestore.Source
+import java.io.IOException
+import java.io.InputStream
+import java.net.HttpURLConnection
+import java.net.URL
+
+
+/**
+ * https://firebase.google.com/docs/firestore/solutions/serve-bundles
+ */
+abstract class SolutionBundles(private val db: FirebaseFirestore) {
+
+    // [START fs_bundle_load]
+    @Throws(IOException::class)
+    fun getBundleStream(urlString: String?): InputStream {
+        val url = URL(urlString)
+        val connection = url.openConnection() as HttpURLConnection
+        return connection.inputStream
+    }
+
+    @Throws(IOException::class)
+    fun fetchFromBundle() {
+        val bundleStream = getBundleStream("https://example.com/createBundle")
+        val loadTask = db.loadBundle(bundleStream)
+
+        // Chain the following tasks
+        // 1) Load the bundle
+        // 2) Get the named query from the local cache
+        // 3) Execute a get() on the named query
+        loadTask.continueWithTask<Query> { task ->
+            // Close the stream
+            bundleStream.close()
+
+            // Calling .result propagates errors
+            val progress = task.getResult(Exception::class.java)
+
+            // Get the named query from the bundle cache
+            db.getNamedQuery("latest-stories-query")
+        }.continueWithTask { task ->
+            val query = task.getResult(Exception::class.java)!!
+
+            // get() the query results from the cache
+            query.get(Source.CACHE)
+        }.addOnCompleteListener { task ->
+            if (!task.isSuccessful) {
+                Log.w(TAG, "Bundle loading failed", task.exception)
+                return@addOnCompleteListener
+            }
+
+            // Get the QuerySnapshot from the bundle
+            val storiesSnap = task.result
+
+            // Use the results
+            // ...
+        }
+    }
+    // [END fs_bundle_load]
+
+    companion object {
+        private const val TAG = "SolutionBundles"
+    }
+}