feat(flutter_tools): upgrade flutter.gradle to update shorebird.yaml (#6)

Author: felangel

packages/flutter_tools/gradle/flutter.gradle

@@ -26,6 +26,7 @@ import org.gradle.api.tasks.TaskAction
 import org.gradle.api.tasks.bundling.Jar
 import org.gradle.internal.os.OperatingSystem
 import org.gradle.util.VersionNumber
+import org.yaml.snakeyaml.Yaml
 
 /** For apps only. Provides the flutter extension used in app/build.gradle. */
 class FlutterExtension {
@@ -63,6 +64,7 @@ buildscript {
     dependencies {
         /* When bumping, also update ndkVersion above. */
         classpath 'com.android.tools.build:gradle:7.3.0'
+        classpath group: 'org.yaml', name: 'snakeyaml', version: '2.0'
     }
 }
 
@@ -975,6 +977,23 @@ class FlutterPlugin implements Plugin<Project> {
                   return
                 }
                 Task copyFlutterAssetsTask = addFlutterDeps(variant)
+                copyFlutterAssetsTask.doLast {  
+                  if (variant.flavorName != null && !variant.flavorName.isEmpty()) {
+                    def outputDir = copyFlutterAssetsTask.destinationDir
+                    def shorebirdYamlFile = new File("${outputDir}/flutter_assets/shorebird.yaml")
+                    def flavor = variant.flavorName                        
+                    def shorebirdYaml = new Yaml().load(shorebirdYamlFile.text)
+                    def flavorAppId = shorebirdYaml['app_id'][flavor]
+                    if (flavorAppId == null) {
+                        throw new GradleException("Cannot find app_id for ${flavor} in shorebird.yaml")
+                    }
+                    def content = 'app_id: ' + flavorAppId + '\n';
+                    if (shorebirdYaml.containsKey('base_url')) {
+                        content += 'base_url: ' + shorebirdYaml['base_url'] + '\n';
+                    }
+                    shorebirdYamlFile.write(content)
+                  }                    
+                }
                 def variantOutput = variant.outputs.first()
                 def processResources = variantOutput.hasProperty("processResourcesProvider") ?
                     variantOutput.processResourcesProvider.get() : variantOutput.processResources