feat(android): inject tauri.conf.json asset, add plugin config load API (#6837)

Author: lucasfernog

.changes/android-load-config.md

@@ -0,0 +1,5 @@
+---
+"tauri": patch
+---
+
+Added static function `loadConfig` on the Android `PluginManager` class.

.changes/inject-config.md

@@ -0,0 +1,6 @@
+---
+"cli.rs": patch
+"cli.js": patch
+---
+
+Inject Tauri configuration in the Android assets.

core/tauri/mobile/android/src/main/java/app/tauri/FsUtils.kt

@@ -6,6 +6,7 @@ package app.tauri
 
 import android.content.ContentUris
 import android.content.Context
+import android.content.res.AssetManager
 import android.database.Cursor
 import android.net.Uri
 import android.os.Environment
@@ -18,6 +19,12 @@ import kotlin.math.min
 
 internal class FsUtils {
   companion object {
+    fun readAsset(assetManager: AssetManager, fileName: String): String {
+      assetManager.open(fileName).bufferedReader().use {
+        return it.readText()
+      }
+    }
+
     fun getFileUrlForUri(context: Context, uri: Uri): String? {
       // DocumentProvider
       if (DocumentsContract.isDocumentUri(context, uri)) {

core/tauri/mobile/android/src/main/java/app/tauri/plugin/PluginManager.kt

@@ -4,12 +4,14 @@
 
 package app.tauri.plugin
 
+import android.content.Context
 import android.content.Intent
 import android.webkit.WebView
 import androidx.activity.result.ActivityResult
 import androidx.activity.result.ActivityResultLauncher
 import androidx.activity.result.contract.ActivityResultContracts
 import androidx.appcompat.app.AppCompatActivity
+import app.tauri.FsUtils
 import app.tauri.JniMethod
 import app.tauri.Logger
 
@@ -123,5 +125,14 @@ class PluginManager(val activity: AppCompatActivity) {
     }
   }
 
+  companion object {
+    fun loadConfig(context: Context, plugin: String): JSObject {
+      val tauriConfigJson = FsUtils.readAsset(context.assets, "tauri.conf.json")
+      val tauriConfig = JSObject(tauriConfigJson)
+      val plugins = tauriConfig.getJSObject("plugins", JSObject())
+      return plugins.getJSObject(plugin, JSObject())
+    }
+  }
+
   private external fun handlePluginResponse(id: Int, success: String?, error: String?)
 }

core/tauri/mobile/proguard-tauri.pro

@@ -1,6 +1,5 @@
 # THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
 
-
 -keep class $PACKAGE.TauriActivity {
   public app.tauri.plugin.PluginManager getPluginManager();
 }

tooling/cli/src/mobile/android.rs

@@ -3,7 +3,13 @@
 // SPDX-License-Identifier: MIT
 
 use clap::{Parser, Subcommand};
-use std::{env::set_var, fs::create_dir, process::exit, thread::sleep, time::Duration};
+use std::{
+  env::set_var,
+  fs::{create_dir, create_dir_all, write},
+  process::exit,
+  thread::sleep,
+  time::Duration,
+};
 use sublime_fuzzy::best_match;
 use tauri_mobile::{
   android::{
@@ -296,3 +302,15 @@ fn open_and_wait(config: &AndroidConfig, env: &Env) -> ! {
     sleep(Duration::from_secs(24 * 60 * 60));
   }
 }
+
+fn inject_assets(config: &AndroidConfig, tauri_config: &TauriConfig) -> Result<()> {
+  let asset_dir = config.project_dir().join("app/src/main/assets");
+  create_dir_all(&asset_dir)?;
+
+  write(
+    asset_dir.join("tauri.conf.json"),
+    serde_json::to_string(&tauri_config)?,
+  )?;
+
+  Ok(())
+}

tooling/cli/src/mobile/android/build.rs

@@ -3,8 +3,8 @@
 // SPDX-License-Identifier: MIT
 
 use super::{
-  configure_cargo, delete_codegen_vars, ensure_init, env, log_finished, open_and_wait, with_config,
-  MobileTarget,
+  configure_cargo, delete_codegen_vars, ensure_init, env, inject_assets, log_finished,
+  open_and_wait, with_config, MobileTarget,
 };
 use crate::{
   build::Options as BuildOptions,
@@ -152,14 +152,16 @@ fn run_build(
   let out_dir = bin_path.parent().unwrap();
   let _lock = flock::open_rw(out_dir.join("lock").with_extension("android"), "Android")?;
 
+  let tauri_config = get_config(options.config.as_deref())?;
+
   let cli_options = CliOptions {
     features: build_options.features.clone(),
     args: build_options.args.clone(),
     noise_level,
     vars: Default::default(),
   };
   let _handle = write_options(
-    &get_config(options.config.as_deref())?
+    &tauri_config
       .lock()
       .unwrap()
       .as_ref()
@@ -175,6 +177,8 @@ fn run_build(
     .get_or_insert(Vec::new())
     .push("custom-protocol".into());
 
+  inject_assets(config, tauri_config.lock().unwrap().as_ref().unwrap())?;
+
   let apk_outputs = if options.apk {
     apk::build(
       config,

tooling/cli/src/mobile/android/dev.rs

@@ -3,8 +3,8 @@
 // SPDX-License-Identifier: MIT
 
 use super::{
-  configure_cargo, delete_codegen_vars, device_prompt, ensure_init, env, open_and_wait,
-  setup_dev_config, with_config, MobileTarget,
+  configure_cargo, delete_codegen_vars, device_prompt, ensure_init, env, inject_assets,
+  open_and_wait, setup_dev_config, with_config, MobileTarget,
 };
 use crate::{
   dev::Options as DevOptions,
@@ -186,8 +186,10 @@ fn run_dev(
         noise_level,
         vars: Default::default(),
       };
+
+      let tauri_config = get_config(options.config.as_deref())?;
       let _handle = write_options(
-        &get_config(options.config.as_deref())?
+        &tauri_config
           .lock()
           .unwrap()
           .as_ref()
@@ -198,6 +200,8 @@ fn run_dev(
         cli_options,
       )?;
 
+      inject_assets(config, tauri_config.lock().unwrap().as_ref().unwrap())?;
+
       if open {
         open_and_wait(config, &env)
       } else if let Some(device) = &device {

tooling/cli/src/mobile/android/open.rs

@@ -2,15 +2,16 @@
 // SPDX-License-Identifier: Apache-2.0
 // SPDX-License-Identifier: MIT
 
-use super::{ensure_init, env, with_config, MobileTarget};
-use crate::Result;
+use super::{ensure_init, env, inject_assets, with_config, MobileTarget};
+use crate::{helpers::config::get as get_config, Result};
 use tauri_mobile::os;
 
 pub fn command() -> Result<()> {
   with_config(
     Some(Default::default()),
     |_root_conf, config, _metadata, _cli_options| {
       ensure_init(config.project_dir(), MobileTarget::Android)?;
+      inject_assets(config, get_config(None)?.lock().unwrap().as_ref().unwrap())?;
       let env = env()?;
       os::open_file_with("Android Studio", config.project_dir(), &env.base).map_err(Into::into)
     },

tooling/cli/templates/mobile/android/app/.gitignore

@@ -1,4 +1,5 @@
 /src/main/{{package-path}}/generated
 /src/main/jniLibs/**/*.so
+/src/main/assets/tauri.conf.json
 /tauri.build.gradle.kts
 /proguard-tauri.pro