Add support for namespace inside build.gradle file.

packages/cli-platform-android/src/config/__tests__/getAndroidProject.test.ts

@@ -6,7 +6,11 @@
  *
  */
 
-import {validatePackageName} from '../getAndroidProject';
+import {
+  validatePackageName,
+  parsePackageNameFromAndroidManifestFile,
+  parseNamespaceFromBuildGradleFile,
+} from '../getAndroidProject';
 
 describe('android::getAndroidProject', () => {
   const expectedResults = {
@@ -34,3 +38,70 @@ describe('android::getAndroidProject', () => {
     });
   });
 });
+
+describe('parsePackageNameFromAndroidManifestFile', () => {
+  it('should parse package name from AndroidManifest', () => {
+    const androidManifest = `<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.example.app"
+    android:versionCode="1"
+    android:versionName="1.0" >
+</manifest>`;
+
+    expect(parsePackageNameFromAndroidManifestFile(androidManifest)).toBe(
+      'com.example.app',
+    );
+  });
+
+  it('should return null if package name is missing from AndroidManifest', () => {
+    const androidManifest = `<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    android:versionCode="1"
+    android:versionName="1.0" >
+</manifest>`;
+
+    expect(parsePackageNameFromAndroidManifestFile(androidManifest)).toBeNull();
+  });
+});
+
+describe('parseNamespaceFromBuildGradleFile', () => {
+  // Test that it can parse a namespace from a build.gradle file
+  it('should parse namespace from build.gradle', () => {
+    const buildGradle = `apply plugin: 'com.android.application'
+
+android {
+    compileSdkVersion 31
+    namespace "com.example.app"
+}`;
+
+    expect(parseNamespaceFromBuildGradleFile(buildGradle)).toBe(
+      'com.example.app',
+    );
+  });
+
+  // Test that it can parse a namespace from a build.gradle.kts file
+  it('should parse namespace from build.gradle.kts', () => {
+    const buildGradle = `plugins {
+    id 'com.android.application'
+}
+
+android {
+    compileSdk = 31
+    namespace = "com.example.app"
+}`;
+
+    expect(parseNamespaceFromBuildGradleFile(buildGradle)).toBe(
+      'com.example.app',
+    );
+  });
+
+  // Test that it returns null if namespace is missing from build.gradle
+  it('should return null if namespace is missing from build.gradle', () => {
+    const buildGradle = `apply plugin: 'com.android.application'
+android {
+    compileSdkVersion 31
+}`;
+
+    expect(parseNamespaceFromBuildGradleFile(buildGradle)).toBeNull();
+  });
+});

packages/cli-platform-android/src/config/findBuildGradle.ts

@@ -0,0 +1,15 @@
+import fs from 'fs';
+import path from 'path';
+
+export function findBuildGradle(sourceDir: string) {
+  const buildGradlePath = path.join(sourceDir, 'build.gradle');
+  const buildGradleKtsPath = path.join(sourceDir, 'build.gradle.kts');
+
+  if (fs.existsSync(buildGradlePath)) {
+    return buildGradlePath;
+  } else if (fs.existsSync(buildGradleKtsPath)) {
+    return buildGradleKtsPath;
+  } else {
+    return null;
+  }
+}

packages/cli-platform-android/src/config/getAndroidProject.ts

@@ -17,23 +17,54 @@ export function getAndroidProject(config: Config) {
 }
 
 /**
- * Get the package name of the running React Native app
- * @param config
+ * Get the package name/namespace of the running React Native app
+ * @param manifestPath The path to the AndroidManifest.xml
+ * @param buildGradlePath The path to the build.gradle[.kts] file.
  */
-export function getPackageName(manifestPath: string) {
+export function getPackageName(
+  manifestPath: string,
+  buildGradlePath: string | null,
+) {
   const androidManifest = fs.readFileSync(manifestPath, 'utf8');
 
-  let packageNameMatchArray = androidManifest.match(/package="(.+?)"/);
-  if (!packageNameMatchArray || packageNameMatchArray.length === 0) {
+  const packageNameFromManifest = parsePackageNameFromAndroidManifestFile(
+    androidManifest,
+  );
+  let packageName;
+  if (packageNameFromManifest) {
+    // We got the package from the AndroidManifest.xml
+    packageName = packageNameFromManifest;
+  } else if (buildGradlePath) {
+    // We didn't get the package from the AndroidManifest.xml,
+    // so we'll try to get it from the build.gradle[.kts] file
+    // via the namespace field.
+    const buildGradle = fs.readFileSync(buildGradlePath, 'utf8');
+    const namespace = parseNamespaceFromBuildGradleFile(buildGradle);
+    if (namespace) {
+      packageName = namespace;
+    } else {
+      throw new CLIError(
+        `Failed to build the app: No package name found. 
+        We couldn't parse the namespace from your build.gradle[.kts] file at ${chalk.underline.dim(
+          `${buildGradlePath}`,
+        )} 
+        and nor your package in the AndroidManifest at ${chalk.underline.dim(
+          `${manifestPath}`,
+        )}
+        `,
+      );
+    }
+  } else {
     throw new CLIError(
-      `Failed to build the app: No package name found. Found errors in ${chalk.underline.dim(
+      `Failed to build the app: No package name found. 
+      We failed to parse your AndroidManifest at ${chalk.underline.dim(
         `${manifestPath}`,
-      )}`,
+      )}
+      and we couldn't find your build.gradle[.kts] file.
+      `,
     );
   }
 
-  let packageName = packageNameMatchArray[1];
-
   if (!validatePackageName(packageName)) {
     logger.warn(
       `Invalid application's package name "${chalk.bgRed(
@@ -46,6 +77,27 @@ export function getPackageName(manifestPath: string) {
   return packageName;
 }
 
+export function parsePackageNameFromAndroidManifestFile(
+  androidManifest: string,
+) {
+  const matchArray = androidManifest.match(/package="(.+?)"/);
+  if (matchArray && matchArray.length > 0) {
+    return matchArray[1];
+  } else {
+    return null;
+  }
+}
+
+export function parseNamespaceFromBuildGradleFile(buildGradle: string) {
+  // search for namespace = inside the build.gradle file via regex
+  const matchArray = buildGradle.match(/namespace\s*[=]*\s*"(.+?)"/);
+  if (matchArray && matchArray.length > 0) {
+    return matchArray[1];
+  } else {
+    return null;
+  }
+}
+
 // Validates that the package name is correct
 export function validatePackageName(packageName: string) {
   return /^[a-z][a-z0-9_]*(\.[a-z][a-z0-9_]*)+$/i.test(packageName);

packages/cli-platform-android/src/config/index.ts

@@ -20,6 +20,7 @@ import {
 import {getPackageName} from './getAndroidProject';
 import {findLibraryName} from './findLibraryName';
 import {findComponentDescriptors} from './findComponentDescriptors';
+import {findBuildGradle} from './findBuildGradle';
 
 /**
  * Gets android project config by analyzing given folder and taking some
@@ -42,12 +43,14 @@ export function projectConfig(
   const manifestPath = userConfig.manifestPath
     ? path.join(sourceDir, userConfig.manifestPath)
     : findManifest(path.join(sourceDir, appName));
+  const buildGradlePath = findBuildGradle(sourceDir);
 
   if (!manifestPath) {
     return null;
   }
 
-  const packageName = userConfig.packageName || getPackageName(manifestPath);
+  const packageName =
+    userConfig.packageName || getPackageName(manifestPath, buildGradlePath);
 
   if (!packageName) {
     throw new Error(`Package name not found in ${manifestPath}`);
@@ -96,12 +99,14 @@ export function dependencyConfig(
   const manifestPath = userConfig.manifestPath
     ? path.join(sourceDir, userConfig.manifestPath)
     : findManifest(sourceDir);
+  const buildGradlePath = path.join(sourceDir, 'build.gradle');
 
   if (!manifestPath) {
     return null;
   }
 
-  const packageName = userConfig.packageName || getPackageName(manifestPath);
+  const packageName =
+    userConfig.packageName || getPackageName(manifestPath, buildGradlePath);
   const packageClassName = findPackageClassName(sourceDir);
 
   /**