# React Native Static Server [![Latest NPM Release](https://img.shields.io/npm/v/@dr.pogodin/react-native-static-server.svg)](https://www.npmjs.com/package/@dr.pogodin/react-native-static-server) [![NPM Downloads](https://img.shields.io/npm/dm/@dr.pogodin/react-native-static-server.svg)](https://www.npmjs.com/package/@dr.pogodin/react-native-static-server) [![CircleCI](https://dl.circleci.com/status-badge/img/gh/birdofpreyru/react-native-static-server/tree/master.svg?style=shield)](https://app.circleci.com/pipelines/github/birdofpreyru/react-native-static-server) [![GitHub Repo stars](https://img.shields.io/github/stars/birdofpreyru/react-native-static-server?style=social)](https://github.com/birdofpreyru/react-native-static-server) [![Dr. Pogodin Studio](https://raw.githubusercontent.com/birdofpreyru/react-native-static-server/master/.README/logo-dr-pogodin-studio.svg)](https://dr.pogodin.studio/docs/react-native-static-server) [@dr.pogodin/react-native-fs]: https://www.npmjs.com/package/@dr.pogodin/react-native-fs [copyFileAssets()]: https://github.com/birdofpreyru/react-native-fs?tab=readme-ov-file#copyfileassets [Error]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error [Example App]: https://github.com/birdofpreyru/react-native-static-server/tree/master/example [Expo Example App #1]: https://github.com/jole141/expo-examples/tree/react-native-static-server [jole141]: https://github.com/jole141 [Expo Example App #2]: https://github.com/benjaminkomen/expo-static-server [benjaminkomen]: https://github.com/benjaminkomen [Expo]: https://expo.dev [getDeviceType()]: https://www.npmjs.com/package/react-native-device-info#getDeviceType [Issue#8]: https://github.com/birdofpreyru/react-native-static-server/issues/8 [Lighttpd]: https://www.lighttpd.net [MainBundlePath]: https://www.npmjs.com/package/@dr.pogodin/react-native-fs#mainbundlepath [mod_access]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_access [mod_alias]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_alias [mod_dirlisting]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_dirlisting [mod_evhost]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_evhost [mod_expire]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_expire [mod_fastcgi]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_fastcgi [mod_indexfile]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_indexfile [mod_redirect]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_redirect [mod_rewrite]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_rewrite [mod_scgi]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_scgi [mod_setenv]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_setenv [mod_simple_vhost]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_simple_vhost [mod_staticfile]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_staticfile [mod_webdav]: https://redmine.lighttpd.net/projects/lighttpd/wiki/Mod_webdav [Promise]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise [react-native-device-info]: https://www.npmjs.com/package/react-native-device-info [React Native]: https://reactnative.dev [TemporaryDirectoryPath]: https://github.com/birdofpreyru/react-native-fs?tab=readme-ov-file#temporarydirectorypath [WebDAV]: https://en.wikipedia.org/wiki/WebDAV Embedded HTTP server for [React Native] applications for Android, iOS, Mac (Catalyst), and Windows platforms; powered by [Lighttpd] server. [![Sponsor](https://raw.githubusercontent.com/birdofpreyru/react-native-static-server/master/.README/sponsor.svg)](https://github.com/sponsors/birdofpreyru) ### Sponsored By:
Luna4 Enterprises Inc. Luna4 Enterprises Inc. — The support for Windows and Mac Catalyst systems would not happen any time soon without their interest and financial contribution.
Integreat App Integreat — Kindly sponsored the support of older Android SDKs (23–27).
[](https://github.com/Lumentric) ### [Contributors](https://github.com/birdofpreyru/react-native-static-server/graphs/contributors) [](https://github.com/jole141) [](https://github.com/exotexot) [](https://github.com/rafalzawadzki) [](https://github.com/birdofpreyru) ## Content - [Getting Started](#getting-started) - [Bundling-in Server Assets Into an App Statically] - [Support of Lighttpd Modules] - [Core and Built-in Modules] - [mod_access](#mod_access) — it is used to deny access to files. - [mod_alias](#mod_alias) — it is used to specify a special document root for a given url-subset. - [mod_dirlisting](#mod_dirlisting) — creates an HTML page listing the contents of the target directory. - [mod_evhost](#mod_evhost) — builds the document-root based on a pattern which contains wildcards. - [mod_expire](#mod_expire) — controls the Cache-Control: max-age response header in HTTP/1.1 or later, and Expires response header in HTTP/1.0. - [mod_fastcgi](#mod_fastcgi) — an interface to external programs that support the FastCGI interface. - [mod_indexfile](#mod_indexfile) — list of files to try when an HTTP request is for a directory. - [mod_redirect](#mod_redirect) — it is used to specify redirects for a set of URLs. - [mod_rewrite](#mod_rewrite) — internal redirects, url rewrite. - [mod_scgi](#mod_scgi) — provides SCGI interface. - [mod_setenv](#mod_setenv) — modifies request headers (from clients), response headers (to clients), and the environment (for CGI). - [mod_simple_vhost](#mod_simple_vhost) — allows to host multiple domain names on a single server. - [mod_staticfile](#mod_staticfile) — is used to serve files. - [Other Modules] - [mod_webdav](#mod_webdav) — provides [WebDAV], a set of HTTP extensions that provides a framework allowing to create, change, and move documents on the server. Essentially an easy way to enable `POST`, `PUT`, _etc._ functionality for selected routes. - [Connecting to an Active Server in the Native Layer] - [API Reference](#api-reference) - [Server] — Represents a server instance. - [constructor()] — Creates a new [Server] instance. - [.addStateListener()] — Adds state listener to the server instance. - [.removeAllStateListeners()] — Removes all state listeners from this server instance. - [.removeStateListener()] — Removes specified state listener from this server instance. - [.start()] — Launches the server. - [.stop()] — Stops the server. - [.errorLog] — Holds `errorLog` configuration. - [.fileDir] — Holds absolute path to static assets on target device. - [.hostname] — Holds the hostname used by server. - [.id] — Hold unique ID of the server instance. - [.nonLocal] — Holds `nonLocal` value provided to [constructor()]. - [.origin] — Holds server origin. - [.port] — Holds the port used by server. - [.state] — Holds the current server state. - [.stopInBackground] — Holds `stopInBackground` value provided to [constructor()]. - ~~[extractBundledAssets()] — Extracts bundled assets into a regular folder (Android-specific).~~ - [getActiveServer()] — Gets the currently active, starting, or stopping server instance, if any, according to the TS layer data. - [getActiveServerId()] — Gets ID of the currently active, starting, or stopping server instance, if any, according to the Native layer data. - [getActiveServerSet()] — Gets a set of currently active, starting, or stopping server instances, if any, according to the TS layer data. - [resolveAssetsPath()] — Resolves relative paths for bundled assets. - [ERROR_LOG_FILE] — Location of the error log file. - [STATES] — Enumerates possible states of [Server] instance. - [UPLOADS_DIR] — Location for uploads. - [WORK_DIR] — Location of the working files. - [ErrorLogOptions] — Options for error logging. ## Getting Started [Getting Started]: #getting-started [CMake]: https://cmake.org [Homebrew]: https://brew.sh - **Note:** - This library's repository includes [Example App]. Have a look, try to build it, in addition to following the instructions below. - The following host / build platforms are not currently supported officially, and they won't be unless the support is provided or sponsored by somebody: - Building for Android target on Windows host ([open issues](https://github.com/birdofpreyru/react-native-static-server/issues?q=is%3Aissue+is%3Aopen+label%3A%22Windows+-%3E+Android%22)). Prefer building for Android on macOS or Ubuntu host. - [Expo] ([open issues](https://github.com/birdofpreyru/react-native-static-server/issues?q=is%3Aissue+is%3Aopen+label%3AExpo)). Though, presumably, the library in its current state works just fine with [Expo] — see [Issue#8] and the following example apps: - [Expo Example App #1] by [jole141]; - [Expo Example App #2] by [benjaminkomen]. - [tvOS](https://developer.apple.com/tvos) ([open issues](https://github.com/birdofpreyru/react-native-static-server/issues?q=is%3Aissue+is%3Aopen+label%3AtvOS)). - [CMake] is required on the build host. - **BEWARE:** [**CMake v3.30.0** breaks the library build for iOS](https://github.com/birdofpreyru/react-native-static-server/issues/111) because of a regression on CMake side, and for this reason it is marked as unsupported on all platforms — be sure to use a different version (v3.22.1–3.29.6 at the moment of writing). - When building for **Android**, [CMake] should be installed as a part of your _Android SDK_ (open _SDK Manager_, and look for [CMake] within the _SDK Tools_ tab). - On **MacOS**, the `pkg-config` dependency is also needed. You can install both via [Homebrew], by executing: ```shell $ brew install cmake pkg-config ``` **IMPORTANT:** - [Homebrew] should have added `eval "$(/opt/homebrew/bin/brew shellenv)"'` command to your `.zshrc` or `.bashrc`. Although this works for interactive terminals, it might not work for sessions inside of other apps, such as XCode, therefore you might need to manually create symbolic links: ```shell $ sudo ln -s $(which cmake) /usr/local/bin/cmake $ sudo ln -s $(which pkg-config) /usr/local/bin/pkg-config ``` For details read: https://earthly.dev/blog/homebrew-on-m1, and [Issue#29](https://github.com/birdofpreyru/react-native-static-server/issues/29). - It looks like with the latest CMake v3.31.6 it is also necessary to sym-link `/usr/local/share/cmake` to point to the `share/cmake` folder of the Homebrew-installed CMake, like so: ```sh $ sudo ln -s /opt/homebrew/Cellar/cmake/3.31.6/share/cmake /usr/local/share/cmake ``` otherwise the build will fail with > _CMake Error: Could not find CMAKE_ROOT !!!_ See [Issue #130](https://github.com/birdofpreyru/react-native-static-server/issues/130) for details. - Install the package and its peer dependencies: ```shell npx install-peerdeps @dr.pogodin/react-native-static-server ``` **Note:** _In case you prefer to install this library from its source code (i.e. directly from its GitHub repo, or a local folder), mind that it depends on several Git sub-modules, which should be clonned and checked out by this command in the library's codebase root: `$ git submodule update --init --recursive`. Released NPM packages of the library have correct versions of the code from these sub-modules bundled into the package, thus no need to clone and check them out after installation from NPM._ - For **Android**: - Android SDK 28 and above [forbids Cleartext / Plaintext HTTP](https://developer.android.com/privacy-and-security/risks/cleartext) by default. Thus, to access locally running server over HTTP from within your app, you should either allow all uses of HTTP in your app by adding `android:usesCleartextTraffic="true"` attribute to `` element in the `AndroidManifest.xml` ([see how it is done in the example app](https://github.com/birdofpreyru/react-native-static-server/blob/master/example/android/app/src/main/AndroidManifest.xml)); or alternatively you should use [network security configuration](https://developer.android.com/privacy-and-security/security-config) to permit cleartext HTTP for selected domains only. - For **iOS**: - After installing the package, enter `ios` folder of the app's codebase and execute ```shell $ pod install ``` - For [Expo]: It is not supported officially, but it is said to work with some additional setup — see [Issue#8] and the following example apps: - [Expo Example App #1] by [jole141]; - [Expo Example App #2] by [benjaminkomen]. - For **Mac Catalyst**: - Disable Flipper in your app's Podfile. - Add _Incoming Connections (Server)_ entitlement to the _App Sandbox_ (`com.apple.security.network.server` entitlement). - If you bundle inside your app the assets to serve by the server, keep in mind that in Mac Catalyst build they'll end up in a different path, compared to the regular iOS bundle (see [Example App]): \ iOS: "[MainBundlePath]`/webroot`"; \ Mac Catalyst: "[MainBundlePath]`/Content/Resources/webroot`". Also keep in mind that `Platform.OS` value equals `"iOS"` both for the normal iOS and for the Mac Catalyst builds, and you should use different methods to distinguish them; for example relying on [getDeviceType()] method of [react-native-device-info] library, which returns `"Desktop"` in case of Catalyst build. - For **Windows**: - Add _Internet (Client & Server)_, _Internet (Client)_, and _Private Networks (Client & Server)_ capabilities to your app. NOTE: _It seems, the core server functionality is able to work without these capabilities, however some functions might be affected, and the error reporting in the current Windows implementation probably won't make it clear that something failed due to the lack of declared capabilities._ - Create and run a server instance: ```jsx import { useEffect, useState } from 'react'; import { Text, View } from 'react-native'; import Server from '@dr.pogodin/react-native-static-server'; // We assume no more than one instance of this component is mounted in the App // at any given time; otherwise some additional logic will be needed to ensure // no more than a single server instance can be launched at a time. // // Also, keep in mind, the call to "server.stop()" without "await" does not // guarantee that the server has shut down immediately after that call, thus // if such component is unmounted and immediately re-mounted again, the new // server instance may fail to launch because of it. export default function ExampleComponent() { const [origin, setOrigin] = useState(''); useEffect(() => { let server = new Server({ // See further in the docs how to statically bundle assets into the App, // alernatively assets to serve might be created or downloaded during // the app's runtime. fileDir: '/path/to/static/assets/on/target/device', }); (async () => { // You can do additional async preparations here; e.g. on Android // it is a good place to extract bundled assets into an accessible // location. // Note, on unmount this hook resets "server" variable to "undefined", // thus if "undefined" the hook has unmounted while we were doing // async operations above, and we don't need to launch // the server anymore. if (server) setOrigin(await server.start()); })(); return () => { setOrigin(''); // No harm to trigger .stop() even if server has not been launched yet. server.stop(); server = undefined; } }, []); return ( Hello World! Server is up at: {origin} ); } ``` ### Bundling-in Server Assets Into an App Statically [Bundling-in Server Assets Into an App Statically]: #bundling-in-server-assets-into-an-app-statically The assets to be served by the server may come to the target device in different ways, for example, they may be generated during the app's runtime, or downloaded to the device by the app from a remote location. They also may be statically bundled-in into the app's bundle at the build time, and it is this option covered in this section. Let's assume the assets to be served by the server are located in the app's codebase inside the folder `assets/webroot` (the path relative to the codebase root), outside `android`, `ios`, and `windows` project folders, as we presumably want to reuse the same assets in both projects, thus it makes sense to keep them outside platform-specific sub-folders. - **Android** - Inside `android/app/build.gradle` file look for `android.sourceSets` section, or create one if it does no exist. To bundle-in our assets for server, it should look like this (note, this way we'll also bundle-in all other content of our `assets` folder, if there is anything beside `webroot` subfolder). ```gradle android { sourceSets { main { assets.srcDirs = [ '../../assets' // This array may contain additional asset folders to bundle-in. // Paths in this array are relative to "build.gradle" file, and // should be comma-separated. ] } } // ... Other stuff. } ``` - On Android the server cannot access bundled assets as regular files, thus before starting the server to serve them, these assets should be extracted into a folder accessible to the server (_e.g._ app's document folder). You can use [copyFileAssets()] function from [@dr.pogodin/react-native-fs] library (v2.24.1 and above): ```jsx // TODO: To be updated, see a better code inside the example app. import { Platform } from 'react-native'; import { copyFileAssets, DocumentDirectoryPath, exists, resolveAssetsPath, unlink, } from '@dr.pogodin/react-native-fs'; async function prepareAssets() { if (Platform.OS !== 'android') return; const targetWebrootPathOnDevice = resolveAssetsPath('webroot'); // It is use-case specific, but in general if target webroot path exists // on the device, probably these assets have been extracted in a previous // app launch, and there is no need to extract them again. However, in most // locations these extracted files won't be delected automatically on // the apps's update, thus you'll need to check it and act accordingly, // which is abstracted as needsOverwrite() function in the condition. const alreadyExtracted = await exists(targetWebrootPathOnDevice); // TODO: Give an example of needsOverwrite(), relying on app version // stored in local files. Maybe we should provide with the library // an utility function which writes to disk a version fingerprint of // the app, thus allowing to detect app updates. For now, have // a look at the example project in the repo, which demonstrates more // realistic code. if (!alreadyExtracted || needsOverwrite()) { // TODO: Careful here, as on platforms different from Android we do not // need to extract assets, we also should not remove them, thus we need // a guard when entering this clean-up / re-extract block. if (alreadyExtracted) await unlink(targetWebrootPathOnDevice); // This function is a noop on other platforms than Android, thus no need // to guard against the platform. await copyFileAssets('webroot', targetWebrootPathOnDevice); } // "webroot" assets have been extracted into the target folder, which now // can be served by the server. } ``` - **iOS** - Open you project's workspace in XCode. - In the «_Project Navigator_» panel right-click on the project name and select «_Add Files to "YOUR-PROJECT-NAME"..._» (alternatively, you can find this option in the XCode head menu under _Files > Add Files to "YOUR-PROJECT-NAME"..._). - In the opened menu do: - Uncheck «_Copy items if needed_»; - Select «_Create folder references_» for «_Added folders_» switch; - Select our `webroot` folder within the file system view; - Press «_Add_» button to add "webroot" assets to the project target. Here is how the dialog & options look, just before pressing «_Add_» button, when adding `assets/webroot` folder to the Xcode project of our [Example App]. ![Dialog screenshot](https://raw.githubusercontent.com/birdofpreyru/react-native-static-server/master/.README/ios-bundling-webroot-folder.png) - The absolute path of `webroot` folder on the device, when added this way, can be obtained as [`resolveAssetsPath('webroot')`][resolveAssetsPath()]. - **Mac Catalyst** - The bundling for iOS explained above also bundles assets for Mac Catalyst; beware, however, the bundled assets end up in a slightly different location inside the bundle in this case (see details earlier in the [Getting Started] section). - **Windows** - Edit `PropertySheet.props` file inside your app's `windows/YOUR_PROJECT_NAME` folder, adding the following nodes into its root `` element: ```xml <_CustomResource Include="..\..\assets\webroot\**\*"> webroot\%(RecursiveDir)%(FileName)%(Extension) true ``` ### Support of Lighttpd Modules [Support of Lighttpd Modules]: #support-of-lighttpd-modules Much of the [Lighttpd]'s functionality is split into dedicated modules that should be explicitly loaded and configured, as per [Lighttpd documentation](https://redmine.lighttpd.net/projects/lighttpd/wiki/Docs_ConfigurationOptions). Support of these modules within this library varies: #### Core and Built-in Modules [Core and Built-in Modules]: #core-and-built-in-modules **BEWARE:** _The following listing of supported modules should be valid for Android, iOS, and macOS target platforms; but most probably it is wrong for Windows, as only `mod_dirlisting.dll` and `mod_webdav.dll` are currently build and explicitly packed with the library. At the moment of writing this, I do not remember in details, how exactly the Windows build of the library and its modules is set up, and do not have an immediate interest to revisit it._ There are three core modules that [Lighttpd] loads by default, and that can be further configured using the `extraConfig` option of [Server]'s [constructor()]: - [mod_dirlisting] — creates an HTML page listing the contents of the target directory. - [mod_indexfile] — list of files to try when an HTTP request is for a directory. - [mod_staticfile] — is used to serve files. For the following, built-in modules, the `extraConfig` option should be used to both load (by listing them within the `server.modules` array), and configure them: - [mod_access] — it is used to deny access to files. - [mod_alias] — it is used to specify a special document root for a given url-subset; for example: ```ts extraConfig: ` server.modules += ("mod_alias") alias.url = ("/sample/url" => "/special/root/path") `, ``` - [mod_evhost] — builds the document-root based on a pattern which contains wildcards. - [mod_expire] — controls the Cache-Control: max-age response header in HTTP/1.1 or later, and Expires response header in HTTP/1.0. - [mod_fastcgi] — provides an interface to external programs that support the FastCGI interface. - [mod_redirect] — it is used to specify redirects for a set of URLs. - [mod_rewrite] — it can be used for interal redirects, URL rewrites by the server, for example: ```ts extraConfig: ` server.modules += ("mod_rewrite") url.rewrite-once = ("/some/path/(.*)" => "/$1") `, // With such configuration, for example, a request // GET "/some/path/file" // will be redirected to // GET "/file" ``` - [mod_scgi] — provides SCGI interface. - [mod_setenv] — modifies request headers (from clients), response headers (to clients), and the environment (for CGI); for example: ```ts extraConfig: ` server.modules += ("mod_setenv") setenv.add-response-header = ( "My-Custom-Header" => "my-custom-value" "Another-Custom-Header" => "another-custom-value" ) setenv.add-request-header = ("X-Proxy" => "my.server.name") `, ``` - [mod_simple_vhost] — allows to host multiple domain names on a single server. #### Other Modules [Other Modules]: #other-modules All other modules require additional efforts to wire them into this library's build process as optional components, which so far has been done only for [mod_webdav](#mod_webdav) module: - [mod_webdav] — provides [WebDAV], a set of HTTP extensions that provides a framework allowing to create, change, and move documents on a server. Essentially an easy way to enable `POST`, `PUT`, _etc._ functionality for selected routes. **BEWARE:** _As of now, props and locks are not supported._ **BEWARE:** _If you have set up the server to serve static assets bundled into the app, the chances are your server works with a readonly location on most platforms (in the case of Android it is anyway necessary to unpack bundled assets to the regular filesystem, thus there the server might be serving from a writeable location already). The easiest way around it is to use [mod_alias][Enabling Alias module] to point URLs configured for [mod_webdav] to a writeable filesystem location, different from that of the served static assets._ To enable [mod_webdav] in the library you need (1) configure your host RN app to build Lighttpd with [mod_webdav] included; (2) opt-in to use it for selected routes when you create [Server] instance, using `extraConfig` option. 1. **Android**: Edit `android/gradle.properties` file of your app, adding this flag in there: ```gradle ReactNativeStaticServer_webdav = true ``` **iOS**: Use environment variable `RN_STATIC_SERVER_WEBDAV=1` when installing or updating the pods (_i.e._ when doing `pod install` or `pod update`). **macOS (Catalyst)**: The same as for iOS. **Windows**: Does not require a special setup — the pre-compiled DLL for [WebDAV] module is always packed with the library, and loaded if opted for by [Server]'s [constructor()]. 2. Use `extraConfig` option of [Server]'s [constructor()] to load [mod_webdav] and use it for selected routes of the created server instance, for example: ```ts extraConfig: ` server.modules += ("mod_webdav") $HTTP["url"] =~ "^/dav/($|/)" { webdav.activate = "enable" } `, ``` ### Connecting to an Active Server in the Native Layer [Connecting to an Active Server in the Native Layer]: #connecting-to-an-active-server-in-the-native-layer When this library is used the regular way, the [Lighttpd] server in the native layer is launched when the [.start()] method of a [Server] instance is triggered on the JavaScript (TypeScript) side, and the native server is terminated when the [.stop()] method is called on the JS side. In the JS layer we hold most of the server-related information (`hostname`, `port`, `fileDir`, _etc._), and take care of the high-level server control (_i.e._ the optional pause / resume of the server when the app enters background / foreground). If JS engine is restarted (or just related JS modules are reloaded) the regular course of action is to explictly terminate the active server just before it, and to re-create, and re-launch it afterwards. If it is not done, the [Lighttpd] server will remain active in the native layer across the JS engine restart, and it won't be possible to launch a new server instance after the restart, as the library only supports at most one active [Lighttpd] server, and it throws an error if the server launch command arrives to the native layer while [Lighttpd] server is already active. However, in response to [the ticket #95](https://github.com/birdofpreyru/react-native-static-server/issues/95) we provide a way to reuse an active native server across JS engine restarts, without restarting the server. To do so you: - Use [getActiveServerId()] method to check whether the native server is active (if so, this method resolves to a non-_null_ ID). - Create a new [Server] instance passing into its [constructor()] that server ID as the `id` option, and [STATES]`.ACTIVE` as the `state` option. These options (usually omitted when creating a regular [Server] instance) ensure that the created [Server] instance is able to communicate with the already running native server, and to correctly handle subsequent [.stop()] and [.start()] calls. Beside these, it is up-to-you to set all other options to the values you need (_i.e._ setting `id`, and `state` just «connects» the newly created [Server] instance to the active native server, but it does not restore any other information about the server — you should restore or redefine it the way you see fit). Note, this way it is possible to create multiple [Server] instances connected to the same active native server. As they have the same `id`, they all will represent the same server, thus calling [.stop()] and [.start()] commands on any of them will operate the same server, and update the states of all these JS server instances, without triggering the error related to the «at most one active server a time» (though, it has not been carefully tested yet). ## API Reference ### Server [Server]: #server ```js import Server from '@dr.pogodin/react-native-static-server'; ``` The [Server] class represents individual server instances. **BEWARE:** At most one server instance can be active within an app at the same time. Attempts to start a new server instance will result in the crash of that new instance. That means, although you may have multiple instances of [Server] class created, you should not call [.start()] method of an instance unless all other server instances are stopped. You may use [getActiveServer()] function to check if there is any active server instance in the app, including a starting or stopping instance. #### constructor() [constructor()]: #constructor ```ts const server = new Server(options: object); ``` Creates a new, inactive server instance. The following settings are supported within `options` argument: - `fileDir` — **string** — The root path on target device from where static assets should be served. Relative paths (those not starting with `/`, neither `file:///`) are automatically prepended by the platform-dependent base path (document directory on Android, or main bundle directory on other platforms; see [resolveAssetsPath()]); however, empty `fileDir` value is forbidden — if you really want to serve all content from the base directory, provide it its absolute path explicitly. - `errorLog` — **boolean** | [ErrorLogOptions] — Optional. If set **true** (treated equivalent to `{}`) the server instance will output basic server state and error logs from the Lighttpd native core into the [ERROR_LOG_FILE]. Passing in an [ErrorLogOptions] object with additional flags allows to add additional debug output from Lighttpd core into the log file. Default value is **false**, in which case the server instance only outputs basic server state and error logs into the OS system log; note that enabling the file logging with this option disables the logging into the system log. **BEWARE:** If you opt for file logging with this option, it is up to you to control and purge the [ERROR_LOG_FILE] as needed. - `extraConfig` — **string** — Optional. If given, it should be a valid piece of [Lighttpd configuration](https://redmine.lighttpd.net/projects/lighttpd/wiki/Docs_Configuration), and it will be appended to the base Lighttpd config generated by this library according to the other server options. - `hostname` — **string** — Optional. Sets the address for server to bind to. - By default, when `nonLocal` option is **false**, `hostname` is set equal "`127.0.0.1`" — the server binds to the loopback address, and it is accessible only from within the host app. - If `nonLocal` option is **true**, and `hostname` was not given, it is initialized with empty string, and later assigned to a library-selected non-local IP address, at the first launch of the server. - If `hostname` value is provided, the server will bind to the given address, and it will ignore `nonLocal` option. _NOTE: In future we'll deprecate `nonLocal` option, and instead will use special `hostname` values to ask the library to automatically select appropriate non-local address._ - `id` — **number** — Optional. Allows to enforce a specific ID, used to communicate with the server instance within the Native layer, thus it allows to re-connect to an existing native server instance. See «[Connecting to an Active Server in the Native Layer]» for details. By default, an `id` is selected by the library. - `nonLocal` — **boolean** — Optional. By default, if `hostname` option was not provided, the server starts at the "`127.0.0.1`" (loopback) address, and it is only accessible within the host app. With this flag set **true** the server will be started on an IP address also accessible from outside the app. _NOTE: When `hostname` option is provided, the `nonLocal` option is ignored. The plan is to deprecate `nonLocal` option in future, in favour of special `hostname` values supporting the current `nonLocal` functionality._ - `port` — **number** — Optional. The port at which to start the server. If 0 (default) an available port will be automatically selected. - `state` — [STATES] — Optional. Allows to enforce the initial server state value, which is necessary [when connecting to an existing native server instance][Connecting to an Active Server in the Native Layer]. Note, it only influence the logic behind subsequent [.start()] and [.stop()] calls, _i.e._ the constructor does not attempt to put the server in this state, nor does it check the value is consistent with the active server, if any, in the native layer. By default, the state is initialized to `STATES.INACTIVE`. - `stopInBackground` — **boolean** — Optional. By default, the server continues to work as usual when its host app enters the background / returns to the foreground (better say, by default, it does not attempt anything special in these situations, but the host OS may kill or restrict it in the background forcefully, depending on OS and app configs). With this flag set **true**, an active server will stop automatically each time the app enters the background, and then automatically launch again each time the app re-enters the foreground. Note that calling [.stop()] explicitly will stop the server for good — no matter `stopInBackground` value, once [.stop()] is called the server won't restart automatically unless you explicitly [.start()] it again. To faciliate debugging, when a server starts / stops automatically because of the `stopInBackground` option and app transitions between the foreground and the background; the corresponding `STARTING` and `STOPPING` messages emitted to the server state listeners (see [.addStateListener()]) will have their `details` values set equal "_App entered background_", and "_App entered foreground_" strings. - **DEPRECATED**: `webdav` — **string[]** — It still works, but it will be removed in future versions. Instead of it use `extraConfig` option to enable and configure [WebDAV] as necessary (see [Enabling WebDAV module]). #### .addStateListener() [.addStateListener()]: #addstatelistener ```ts server.addStateListener(listener: StateListener): Unsubscribe; // where StateListener and Unsubscribe signatures are: type StateListener = (state: string, details: string, error?: Error) => void; type UnsubscribeFunction = () => void; ``` Adds given state listener to the server instance. The listener will be called each time the server state changes, with the following arguments: - `state` — **string** — The new state, one of [STATES] values. - `details` — **string** — Additional details about the state change, if any can be provided; an empty string otherwise. - `error` — [Error] — If server instance crashes, this will be the related error object; otherwise undefined. This method returns "unsubscribe" function, call it to remove added listener from the server instance. #### .removeAllStateListeners() [.removeAllStateListeners()]: #removeallstatelisteners ```ts server.removeAllStateListeners() ``` Removes all state listeners connected to the server instance. #### .removeStateListener() [.removeStateListener()]: #removestatelistener ```ts server.removeStateListener(listener: StateListener) ``` Removes given state `listener` if it is connected to the server instance; does nothing otherwise. #### .start() [.start()]: #start ```ts server.start(details?: string): Promise ``` Starts [Server] instance. It returns a [Promise], which resolves to the server's [origin][.origin] once the server reaches `ACTIVE` [state][.state], thus becomes ready to handle requests. The promise rejects in case of start failure, _i.e._ if server ends up in the `CRASHED` state before becoming `ACTIVE`. This method is safe to call no matter the current state of this server instance. If it is `ACTIVE`, the method just resolves to [origin][.origin] right away; if `CRASHED`, it attempts a new start of the server; otherwise (`STARTING` or `STOPPING`), it will wait until the server reaches one of resulting states (`ACTIVE`, `CRASHED`, or `INACTIVE`), then acts accordingly. The optional `details` argument, if provided, will be added to the `STARTING` message emitted to the server state change listeners (see [.addStateListener()]) in the beginning of this method, if the server launch is necessary. **BEWARE:** With the current library version, at most one server instance can be active within an app at any time. Calling [.start()] when another server instance is running will result in the start failure and `CRASHED` state. See also [getActiveServer()]. #### .stop() [.stop()]: #stop ```ts server.stop(details?: string): Promise<> ``` Gracefully shuts down the server. It returns a [Promise] which resolve once the server is shut down, _i.e._ reached `INACTIVE` [state](.state). The promise rejects if an error happens during shutdown, and server ends up in the `CRASHED` state. If server was created with `pauseInBackground` option, calling `.stop()` will also ensure that the stopped server won't be restarted when the app re-enters foreground. Once stopped, the server only can be re-launched by an explicit call of [.start()]. It is safe to call this method no matter the current state of this server. If it is `INACTIVE` or `CRASHED`, the call will just cancel automatic restart of the server, if one is scheduled by `pauseInBackground` option, as mentioned above. If it is `STARTING` or `STOPPING`, this method will wait till server reaching another state (`ACTIVE`, `INACTIVE` or `CRASHED`), then it will act accordingly. The optional `details` argument, if provided, will be added to the `STARTING` message emitted to the server state change listeners (see [.addStateListener()]) in the beginning of this method, if the server launch is necessary. #### .errorLog [.errorLog]: #errorlog ```ts server.errorLog: false | ErrorLogOptions; ``` Readonly property. It holds the error log configuration (see [ErrorLogOptions]), opted for at the time of this server instance [construction][constructor()]. Note, it will be `{}` if `errorLog` option of [constructor()] was set **true**; and it will be **false** (default) if `errorLog` option was omitted in the [constructor()] call. #### .fileDir [.fileDir]: #filedir ```ts server.fileDir: string; ``` Readonly property. It holds `fileDir` value — the absolute path on target device from which static assets are served by the server. #### .hostname [.hostname]: #hostname ```ts server.hostname: string; ``` Readonly property. It holds the hostname used by the server. If no `hostname` value was provided to the server's [constructor()], this property will be: - Without `nonLocal` option it will be equal `127.0.0.1` (the loopback address) from the very beginning; - Otherwise, it will be an empty string until the first launch of the server instance, after which it will become equal to the IP address selected by the server automatically, and won't change upon subsequent server re-starts. #### .id [.id]: #id ```ts server.id: number; ``` Readonly. It holds unique ID number of the server instance, which is used internally for communication between JS an native layers, and also exposed to the library consumer, for debug. **BEWARE:** In the current library implementation, this ID is generated simply as `Date.now() % 65535`, which is not random, and not truly unique — the ID collision probability across different server instances is high. This should be fine as long as you don't create many server instances in your app, and don't rely on the uniqueness of these IDs across different app launches. Switching to real UUIDs is on radar, but not the highest priority for now. #### .nonLocal [.nonLocal]: #nonlocal ```ts server.nonLocal: boolean; ``` Readonly property. It holds `nonLocal` value provided to server [constructor()]. #### .origin [.origin]: #origin ```ts server.origin: string; ``` Readonly property. It holds server origin. Initially it equals empty string, and after the first launch of server instance it becomes equal to its origin, _i.e._ "`http://HOSTNAME:PORT`", where `HOSTNAME` and `PORT` are selected hostname and port, also accessible via [.hostname] and [.port] properties. #### .port [.port]: #port ```ts server.port: number; ``` Readonly property. It holds the port used by the server. Initially it equals the `port` value provided to [constructor()], or 0 (default value), if it was not provided. If it is 0, it will change to the automatically selected port number once the server is started the first time. The selected port number does not change upon subsequent re-starts of the server. #### .state [.state]: #state ```ts server.state: STATES; ``` Readonly property. It holds current server state, which is one of [STATES] values. Use [.addStateListener()] method to watch for server state changes. #### .stopInBackground [.stopInBackground]: #stopinbackground ```ts server.stopInBackground: boolean; ``` Readonly property. It holds `stopInBackground` value provided to [constructor()]. ### extractBundledAssets() **DEPRECATED!** _Use instead [copyFileAssets()] from the [@dr.pogodin/react-native-fs] library v2.24.1 and above — it does the same job in a more efficient way (it is implemented entirely in the native layer, thus does not incur the overhead of recurrent communication between the native and JS layers during the operation)._ _The [extractBundledAssets()], with its original implementation, will be kept around for backward compatibility, but it will be removed in future!_ [extractBundledAssets()]: #extractbundledassets ```ts import {extractBundledAssets} from '@dr.pogodin/react-native-static-server'; extractBundledAssets(into, from): Promise<>; ``` Extracts bundled assets into the specified regular folder, preserving asset folder structure, and overwriting any conflicting files in the destination. This is an Android-specific function; it does nothing on other platforms. **Arguments** - `into` — **string** — Optional. The destination folder for extracted assets. By default assets are extracted into the app's document folder. - `from` — **string** — Optional. Relative path to the root asset folder, starting from which all assets contained in that folder and its sub-folders will be extracted into the destination folder, preserving asset folder structure. By default all bundled assets are extracted. **Returns** [Promise] which resolves once the extraction is completed. ### getActiveServer() [getActiveServer()]: #getactiveserver ```ts import {getActiveServer} from '@dr.pogodin/react-native-static-server'; getActiveServer(): Server | undefined; ``` Returns the currently active, starting, or stopping [Server] instance, if any exist in the app. It does not return, however, any inactive server instance which has been stopped automatically because of `stopInBackground` option, when the app entered background, and might be automatically started in future if the app enters foreground again prior to an explicit [.stop()] call for that instance. **NOTE:** - The result of this function is based on the TypeScript layer data (that's why it is synchronous), in contrast to the [getActiveServerId()] function below, which calls into the Native layer, and returns ID of the active server based on that. - The feature «[Connecting to an Active Server in the Native Layer]» creates a possibility to have several active server instances in TS layer, all connected to the same active server on the native side. For this reason we also provide [getActiveServerSet()] function, which returns a set of all active server instances on TS side. [getActiveServer()] just returns the first server instance from that set. ### getActiveServerId() [getActiveServerId()]: #getactiveserverid ```ts import {getActiveServerId} from '@dr.pogodin/react-native-static-server'; getActiveServerId(): Promise; ``` Returns ID of the currently active, starting, or stopping server instance, if any exist in the Native layer. This function is provided in response to [the ticket #95](https://github.com/birdofpreyru/react-native-static-server/issues/95), to allow «[Connecting to an Active Server in the Native Layer]». The ID returned by this function can be passed in into [Server] instance [constructor()] to create server instance communicating to the existing native layer server. **NOTE:** It is different from [getActiveServer()] function above, which returns the acurrently active, starting, or stopping [Server] instance based on TypeScript layer data. ### getActiveServerSet() [getActiveServerSet()]: #getactiveserverset ```ts import {getActiveServer} from '@dr.pogodin/react-native-static-server'; getActiveServer(): Set | undefined; ``` Returns a set of currently active, starting, or stopping [Server] instances, if any exist in the app. **NOTE:** - On the native side, there cannot be more than one active (or starting, or stopping) server instance at any time, and the native ID of that server instance can be retrieved by the [getActiveServerId()] function. However, on TS side user can create multiple [Server] object instances, connected to the same native instance (see «[Connecting to an Active Server in the Native Layer]») — that is how it is possible to have more than one active [Server] on TS side. In normal use, however, this set will have only a single active [Server], and you may use [getActiveServer()] function instead, which always returns the first item in this set. - When there is no active server instance, this function returns `undefined` (rather than an empty set). ### resolveAssetsPath() [resolveAssetsPath()]: #resolveassetspath ```ts import {resolveAssetsPath} from '@dr.pogodin/react-native-static-server'; resolveAssetsPath(path: string): string; ``` If given `path` is relative, it returns the corresponding absolute path, resolved relative to the platform-specific base location (document folder on Android; or main bundle folder on other platforms) for bundled assets; otherwise, it just returns given absolute `path` as is. In other words, it exposes the same path resolution logic used by [Server]'s [constructor()] for relative values of its `fileDir` argument. **Arguments** - `path` — **string** — Absolute or relative path. Returns **string** — The corresponding absolute path. ### ERROR_LOG_FILE [ERROR_LOG_FILE]: #error_log_file ```ts import {ERROR_LOG_FILE} from '@dr.pogodin/react-native-static-server'; ``` Constant **string**. It holds the filesystem location of the error log file (see `errorLog` option of Server's [constructor()]). The actual value is "[WORK_DIR]`/errorlog.txt`" — all server instances within an app output their logs, when opted, into the same file; and it is up to the host app to purge this file when needed. ### STATES [STATES]: #states ```js import {STATES} from '@dr.pogodin/react-native-static-server'; ``` The [STATES] enumerator provides possible states of a server instance: - `STATES.ACTIVE` — Up and running. - `STATES.CRASHED` — Crashed and inactive. - `STATES.INACTIVE` — Yet not started, or gracefully shut down. - `STATES.STARTING` — Starting up. - `STATES.STOPPING` — Shutting down. It also contains the backward mapping between state numeric values and their human-readable names used above, _i.e._ ```js console.log(STATES.ACTIVE); // Logs: 0 console.log(STATES[0]); // Logs: ACTIVE ``` ### UPLOADS_DIR [UPLOADS_DIR]: #uploads_dir ```ts import {UPLOADS_DIR} from '@dr.pogodin/react-native-static-server'; ``` Constant **string**. It holds the filesystem location where all server instances within an app keep any uploads to the server. The actual value is "[WORK_DIR]`/uploads`". ### WORK_DIR [WORK_DIR]: #work_dir ```ts import {WORK_DIR} from '@dr.pogodin/react-native-static-server'; ``` Constant **string**. It holds the filesystem location where all server instances within an app keep their working files (configs, logs, uploads). The actual value is "[TemporaryDirectoryPath]`/__rn-static-server__`", where [TemporaryDirectoryPath] is the temporary directory path for the app as reported by the [@dr.pogodin/react-native-fs] library. ### ErrorLogOptions [ErrorLogOptions]: #errorlogoptions ```ts import {type ErrorLogOptions} from '@dr.pogodin/react-native-static-server'; ``` The type of `errorLog` option of the Server's [constructor()]. It describes an object with the following optional boolean flags; each of them enables the similarly named [Lighttpd debug option](https://redmine.lighttpd.net/projects/lighttpd/wiki/DebugVariables): - `conditionHandling` — **boolean** — Optional. - `fileNotFound` — **boolean** — Optional. - `requestHandling` — **boolean** — Optional. - `requestHeader` — **boolean** — Optional. - `requestHeaderOnError` — **boolean** — Optional. - `responseHeader` — **boolean** — Optional. - `timeouts` — **boolean** — Optional. Without any flag set the server instance will still output very basic state and error messages into the log file.