Binary Hashing (Android) (#401)

binary hashing android

Author: geof90

scripts/generateBundledResourcesHash.js

@@ -1,10 +1,10 @@
 /*
  * This script generates a hash of all the React Native bundled assets and writes it into
- * into the APK. The hash in "updateCheck" requests to prevent downloading an identical 
+ * into the APK. The hash in "updateCheck" requests to prevent downloading an identical
  * update to the one already present in the binary.
- * 
- * It first creates a snapshot of the contents in the resource directory by creating 
- * a map with the modified time of all the files in the directory. It then compares this 
+ *
+ * It first creates a snapshot of the contents in the resource directory by creating
+ * a map with the modified time of all the files in the directory. It then compares this
  * snapshot with the one saved earlier in "recordFilesBeforeBundleCommand.js" to figure
  * out which files were generated by the "react-native bundle" command. It then computes
  * the hash for each file to generate a manifest, and then computes a hash over the entire
@@ -49,44 +49,53 @@ var manifest = [];
 if (bundleGeneratedAssetFiles.length) {
     bundleGeneratedAssetFiles.forEach(function(assetFile) {
         // Generate hash for each asset file
-        var readStream = fs.createReadStream(resourcesDir + assetFile);
-        var hashStream = crypto.createHash(HASH_ALGORITHM);
-
-        readStream.pipe(hashStream)
-            .on("error", function(error) {
-                throw error;
-            })
-            .on("finish", function() {
-                hashStream.end();
-                var buffer = hashStream.read();
-                var fileHash = buffer.toString("hex");
-                manifest.push(CODE_PUSH_FOLDER_PREFIX + assetFile.replace(/\\/g, "/") + ":" + fileHash);
-                
-                if (manifest.length === bundleGeneratedAssetFiles.length) {
-                    // Generate hash for JS bundle
-                    readStream = fs.createReadStream(jsBundleFilePath);
-                    hashStream = crypto.createHash(HASH_ALGORITHM);
-                    readStream.pipe(hashStream)
-                        .on("error", function(error) {
-                            throw error;
-                        })
-                        .on("finish", function() {
-                            hashStream.end();
-                            var buffer = hashStream.read();
-                            var fileHash = buffer.toString("hex");
-                            manifest.push(CODE_PUSH_FOLDER_PREFIX + "/" + path.basename(jsBundleFilePath) + ":" + fileHash);
-                            manifest = manifest.sort();
-                            
-                            var finalHash = crypto.createHash(HASH_ALGORITHM)
-                                .update(JSON.stringify(manifest))
-                                .digest("hex");
-                            
-                            var savedResourcesManifestPath = assetsDir + "/" + CODE_PUSH_HASH_FILE_NAME;
-                            fs.writeFileSync(savedResourcesManifestPath, finalHash);
-                        });
-                }
-            });
+        addFileToManifest(resourcesDir, assetFile, manifest, function() {
+            if (manifest.length === bundleGeneratedAssetFiles.length) {
+                // Generate hash for JS bundle
+                addFileToManifest(path.dirname(jsBundleFilePath), path.basename(jsBundleFilePath), manifest, function() {
+                    // ...and the JS bundle "meta"
+                    var jsBundleMetaFilePath = jsBundleFilePath + ".meta";
+                    addFileToManifest(path.dirname(jsBundleMetaFilePath), path.basename(jsBundleMetaFilePath), manifest, function() {
+                        manifest = manifest.sort();
+                        var finalHash = crypto.createHash(HASH_ALGORITHM)
+                            .update(JSON.stringify(manifest))
+                            .digest("hex");
+
+                        var savedResourcesManifestPath = assetsDir + "/" + CODE_PUSH_HASH_FILE_NAME;
+                        fs.writeFileSync(savedResourcesManifestPath, finalHash);
+                    });
+                });
+            }
+        });
     });
 }
 
+function addFileToManifest(folder, assetFile, manifest, done) {
+    var fullFilePath = path.join(folder, assetFile);
+    if (!fileExists(fullFilePath)) {
+        done();
+        return;
+    }
+
+    var readStream = fs.createReadStream(path.join(folder, assetFile));
+    var hashStream = crypto.createHash(HASH_ALGORITHM);
+
+    readStream.pipe(hashStream)
+        .on("error", function(error) {
+            throw error;
+        })
+        .on("finish", function() {
+            hashStream.end();
+            var buffer = hashStream.read();
+            var fileHash = buffer.toString("hex");
+            manifest.push(path.join(CODE_PUSH_FOLDER_PREFIX, assetFile).replace(/\\/g, "/") + ":" + fileHash);
+            done();
+        });
+}
+
+function fileExists(file) {
+    try { return fs.statSync(file).isFile(); }
+    catch (e) { return false; }
+}
+
 fs.unlinkSync(TEMP_FILE_PATH);