# react-native-fetch-blob [![npm](https://img.shields.io/npm/v/react-native-fetch-blob.svg?style=flat-square)]() ![](https://img.shields.io/badge/PR-Welcome-brightgreen.svg?style=flat-square) [![npm](https://img.shields.io/npm/l/express.svg?maxAge=2592000&style=flat-square)]() A module provides upload, download, and files access API. Supports file stream read/write for process large files. **Why do we need this** React Native does not support `Blob` object at this moment, which means if you're going to send/receive binary data via `fetch` API, that might not work as you expect. See [[fetch] Does fetch with blob() marshal data across the bridge?](https://github.com/facebook/react-native/issues/854). For some uses cases, you might get into trouble. For example, displaying an image that requires a specific field in headers (ex. "Authorization : Bearer ...") or body, so you can't just pass the image uri to `Image` component because that will probably returns a 401 response. Or you're going to upload binary data which generated from JS, the server will get an empry body due to [this issue](https://github.com/facebook/react-native/issues/854). With help of this APIs provides by this module, you can send HTTP request with any headers, and decide how to handle the response/reqeust data without worry about if it is not supported by `fetch` API. The response data can be just simply converted into BASE64 string, or store to a file directly so that you can read it by file access APIs such as readFile, readStream. This module was designed to be a substitution of `Blob`, there's a set of APIs including basic file system CRUD method, and file stream reader/writer. Also it has a special `fetch` implementation that supports binary request/response body. **Pre v0.5.0 Users** This update is `backward-compatible` generally you don't have to change existing code unless you're going to use new APIs. In latest version (v0.5.0), new APIs can either `upload` or `download` files simply using a file path. It's much more memory efficent in some use case. We've also introduced `fs` APIs for access files, and `file stream` API that helps you read/write files (especially for **large ones**), see [Examples](#user-content-usage) bellow. This module implements native methods, supports both Android (uses awesome native library [AsyncHttpClient](https://github.com/AsyncHttpClient/async-http-client])) and IOS. ## TOC * [Installation](#user-content-installation) * [Guide](#user-content-guide) * [Download file](#user-content-download-example--fetch-files-that-needs-authorization-token) * [Upload file](#user-content-upload-example--dropbox-files-upload-api) * [Multipart/form upload](#user-content-multipartform-data-example--post-form-data-with-file-and-data) * [Upload/Download progress](#user-content-uploaaddownload-progress) * [Android Media Scanner, and Download Manager Support](#user-content-android-media-scanner-and-downloads-app-support) * [File access](#user-content-file-access) * [File stream](#user-content-file-stream) * [Manage cached files](#user-content-manage-cached-files) * [Self-Signed SSL Server](#user-content-self-signed-ssl-server) * [API References](https://github.com/wkh237/react-native-fetch-blob/wiki/Fetch-API) * [Development](#user-content-development) ## Installation Install package from npm ```sh npm install --save react-native-fetch-blob ``` Link package using [rnpm](https://github.com/rnpm/rnpm) ```sh rnpm link ``` **Grant Permission to External storage for Android 5.0 or lower** Mechanism about granting Android permissions has slightly different since Android 6.0 released, please refer to [Officail Document](https://developer.android.com/training/permissions/requesting.html). If you're going to access external storage (say, SD card storage) for `Android 5.0` (or lower) devices, you might have to add the following line to `AndroidManifetst.xml`. ```diff + + ... ``` Also, if you're going to use `Android Download Manager` you have to add this to `AndroidManifetst.xml` ```diff + ``` **Grant Access Permission for Android 6.0** Beginning in Android 6.0 (API level 23), users grant permissions to apps while the app is running, not when they install the app. So adding permissions in `AndroidManifest.xml` won't work in Android 6.0 devices. To grant permissions in runtime, you might use modules like [react-native-android-permissions](https://github.com/lucasferreira/react-native-android-permissions). ## Guide ```js import RNFetchBlob from 'react-native-fetch-blob' ``` #### Download example : Fetch files that needs authorization token ```js // send http request in a new thread (using native code) RNFetchBlob.fetch('GET', 'http://www.example.com/images/img1.png', { Authorization : 'Bearer access-token...', // more headers .. }) // when response status code is 200 .then((res) => { // the conversion is done in native code let base64Str = res.base64() // the following conversions are done in js, it's SYNC let text = res.text() let json = res.json() }) // Status code is not 200 .catch((errorMessage, statusCode) => { // error handling }) ``` #### Download to storage directly The simplest way is give a `fileCach` option to config, and set it to `true`. This will let the incoming response data stored in a temporary path **wihout** any file extension. **These files won't be removed automatically, please refer to [Cache File Management](#user-content-cache-file-management)** ```js RNFetchBlob .config({ // add this option that makes response data to be stored as a file, // this is much more performant. fileCache : true, }) .fetch('GET', 'http://www.example.com/file/example.zip', { some headers .. }) .then((res) => { // the temp file path console.log('The file saved to ', res.path()) }) ``` **Set Temp File Extension** Sometimes you might need a file extension for some reason. For instance, when using file path as source of `Image` component, the path should end with something like .png or .jpg, you can do this by add `appendExt` option to `config`. ```js RNFetchBlob .config({ fileCache : true, // by adding this option, the temp files will have a file extension appendExt : 'png' }) .fetch('GET', 'http://www.example.com/file/example.zip', { some headers .. }) .then((res) => { // the temp file path with file extension `png` console.log('The file saved to ', res.path()) // Beware that when using a file path as Image source on Android, // you must prepend "file://"" before the file path imageView = }) ``` **Use Specific File Path** If you prefer a specific path rather than random generated one, you can use `path` option. We've added a constant [dirs](#user-content-dirs) in v0.5.0 that contains several common used directories. ```js let dirs = RNFetchBlob.fs.dirs RNFetchBlob .config({ // response data will be saved to this path if it has access right. path : dirs.DocumentDir + '/path-to-file.anything' }) .fetch('GET', 'http://www.example.com/file/example.zip', { //some headers .. }) .then((res) => { // the path should be dirs.DocumentDir + 'path-to-file.anything' console.log('The file saved to ', res.path()) }) ``` **These files won't be removed automatically, please refer to [Cache File Management](#user-content-cache-file-management)** #### Upload example : Dropbox [files-upload](https://www.dropbox.com/developers/documentation/http/documentation#files-upload) API `react-native-fetch-blob` will convert the base64 string in `body` to binary format using native API, this process will be done in a new thread, so it's async. ```js RNFetchBlob.fetch('POST', 'https://content.dropboxapi.com/2/files/upload', { Authorization : "Bearer access-token...", 'Dropbox-API-Arg': JSON.stringify({ path : '/img-from-react-native.png', mode : 'add', autorename : true, mute : false }), 'Content-Type' : 'application/octet-stream', // here's the body you're going to send, should be a BASE64 encoded string // (you can use "base64" APIs to make one). // The data will be converted to "byte array"(say, blob) before request sent. }, base64ImageString) .then((res) => { console.log(res.text()) }) .catch((err) => { // error handling .. }) ``` #### Upload a file from storage If you're going to use a `file` request body, just wrap the path with `wrap` API. ```js RNFetchBlob.fetch('POST', 'https://content.dropboxapi.com/2/files/upload', { // dropbox upload headers Authorization : "Bearer access-token...", 'Dropbox-API-Arg': JSON.stringify({ path : '/img-from-react-native.png', mode : 'add', autorename : true, mute : false }), 'Content-Type' : 'application/octet-stream', // Change BASE64 encoded data to a file path with prefix `RNFetchBlob-file://`. // Or simply wrap the file path with RNFetchBlob.wrap(). }, RNFetchBlob.wrap(PATH_TO_THE_FILE)) .then((res) => { console.log(res.text()) }) .catch((err) => { // error handling .. }) ``` #### Multipart/form-data example : Post form data with file and data In `version >= 0.3.0` you can also post files with form data, just put an array in `body`, with elements have property `name`, `data`, and `filename`(optional). Elements have property `filename` will be transformed into binary format, otherwise it turns into utf8 string. ```js RNFetchBlob.fetch('POST', 'http://www.example.com/upload-form', { Authorization : "Bearer access-token", otherHeader : "foo", 'Content-Type' : 'multipart/form-data', }, [ // element with property `filename` will be transformed into `file` in form data { name : 'avatar', filename : 'avatar.png', data: binaryDataInBase64}, // elements without property `filename` will be sent as plain text { name : 'name', data : 'user'}, { name : 'info', data : JSON.stringify({ mail : 'example@example.com', tel : '12345678' })}, ]).then((resp) => { // ... }).catch((err) => { // ... }) ``` What if you want to upload a file in some field ? Just like [upload a file from storage](#user-content-upload-a-file-from-storage) example, wrap `data` by `wrap` API (this feature is only available for `version >= v0.5.0`) ```js RNFetchBlob.fetch('POST', 'http://www.example.com/upload-form', { Authorization : "Bearer access-token", otherHeader : "foo", // this is required, otherwise it won't be process as a multipart/form-data request 'Content-Type' : 'multipart/form-data', }, [ // append field data from file path { name : 'avatar', filename : 'avatar.png', // Change BASE64 encoded data to a file path with prefix `RNFetchBlob-file://`. // Or simply wrap the file path with RNFetchBlob.wrap(). data: RNFetchBlob.wrap(PATH_TO_THE_FILE) }, // elements without property `filename` will be sent as plain text { name : 'name', data : 'user'}, { name : 'info', data : JSON.stringify({ mail : 'example@example.com', tel : '12345678' })}, ]).then((resp) => { // ... }).catch((err) => { // ... }) ``` #### Upload/Download progress In `version >= 0.4.2` it is possible to know the upload/download progress. ```js RNFetchBlob.fetch('POST', 'http://www.example.com/upload', { ... some headers, 'Content-Type' : 'octet-stream' }, base64DataString) .progress((received, total) => { console.log('progress', received / total) }) .then((resp) => { // ... }) .catch((err) => { // ... }) ``` #### Android Media Scanner, and Download Manager Support If you want to make a file in `External Storage` becomes visible in Picture, Downloads, or other built-in apps, you will have to use `Media Scanner` or `Download Manager`. **Media Scanner** Media scanner scan the file and categorize by given MIME type, if MIME type not specified, it will try to resolve the file using its file extension. ```js RNFetchBlob .config({ // DCIMDir is in external storage path : dirs.DCIMDir + '/music.mp3' }) .fetch('GET', 'http://example.com/music.mp3') .then((res) => RNFetchBlob.fs.scanFile([ { path : res.path(), mime : 'audio/mpeg' } ])) .then(() => { // scan file success }) .catch((err) => { // scan file error }) ``` **Download Manager** When download large files on Android it is recommended to use `Download Manager`, it supports lot of native features like progress bar, and notification, also the download task will be handled by OS, and more effective. When using DownloadManager, `fileCache` and `path` properties in `config` will not take effect, because Android DownloadManager can only store files to external storage. When download complete, DownloadManager will generate a file path so that you can deal with it. ```js RNFetchBlob .config({ addAdnroidDownloads : { useDownloadManager : true, // <-- this is the only thing required // Optional, override notification setting (default to true) notification : false, // Optional, but recommended since android DownloadManager will fail when // the url does not contains a file extension, by default the mime type will be text/plain mime : 'text/plain', description : 'File downloaded by download manager.' } }) .fetch('GET', 'http://example.com/file/somefile') .then((resp) => { // the path of downloaded file resp.path() }) ``` **Download Notification and Visibiliy in Download App (Android Only)** If you want to display a notification when file's completely download to storage (as the above), or make the downloaded file visible in "Downloads" app. You have to add some options to `config`. ```js RNFetchBlob.config({ fileCache : true, // android only options, these options be a no-op on IOS addAndroidDownloads : { // Show notification when response data transmitted notification : true, // Title of download notification title : 'Great ! Download Success ! :O ', // File description (not notification description) description : 'An image file.', mime : 'image/png', // Make the file scannable by media scanner meidaScannable : true, } }) .fetch('GET', 'http://example.com/image1.png') .then(...) ``` #### File Access File access APIs were made when developing `v0.5.0`, which helping us write tests, and was not planned to be a part of this module. However I realized that, it's hard to find a great solution to manage cached files, every one who use this moudle may need those APIs for there cases. Here's the list of `fs` APIs - dirs - createFile - readFile - writeFile - appendFile - readStream - writeStream - unlink - mkdir - ls - mv - cp - exists - isDir - lstat - stat - scanFile (Android Only) See [File API](https://github.com/wkh237/react-native-fetch-blob/wiki/File-System-Access-API) for more information #### File Stream In `v0.5.0` we've added `writeStream` and `readStream`, which allows your app read/write data from file path. This API creates a file stream, rather than convert whole data into BASE64 encoded string, it's handy when processing **large files**. When calling `readStream` method, you have to `open` the stream, and start to read data. ```js let data = '' RNFetchBlob.readStream( // encoding, should be one of `base64`, `utf8`, `ascii` 'base64', // file path PATH_TO_THE_FILE, // (optional) buffer size, default to 4096 (4095 for BASE64 encoded data) // when reading file in BASE64 encoding, buffer size must be multiples of 3. 4095) .then((ifstream) => { ifstream.open() ifstream.onData((chunk) => { // when encoding is `ascii`, chunk will be an array contains numbers // otherwise it will be a string data += chunk }) ifstream.onError((err) => { console.log('oops', err) }) ifstream.onEnd(() => { { ofstream.write('foo') ofstream.write('bar') ofstream.close() }) ``` #### Cache File Management When using `fileCache` or `path` options along with `fetch` API, response data will automatically stored into file system. The files will **NOT** removed unless you `unlink` it. There're several ways to remove the files ```js // remove file using RNFetchblobResponse.flush() object method RNFetchblob.config({ fileCache : true }) .fetch('GET', 'http://example.com/download/file') .then((res) => { // remove cached file from storage res.flush() }) // remove file by specifying a path RNFetchBlob.fs.unlink('some-file-path').then(() => { // ... }) ``` You can also grouping requests by using `session` API, and use `dispose` to remove them all when needed. ```js RNFetchblob.config({ fileCache : true }) .fetch('GET', 'http://example.com/download/file') .then((res) => { // set session of a response res.session('foo') }) RNFetchblob.config({ // you can also set session beforehand session : 'foo' fileCache : true }) .fetch('GET', 'http://example.com/download/file') .then((res) => { // ... }) // or put an existing file path to the session RNFetchBlob.session('foo').add('some-file-path') // remove a file path from the session RNFetchBlob.session('foo').remove('some-file-path') // list paths of a session RNFetchBlob.session('foo').list() // remove all files in a session RNFetchBlob.session('foo').dispose().then(() => { ... }) ``` #### Self-Signed SSL Server By default, react-native-fetch-blob does NOT allow connection to unknown certification provider since it's dangerous. If you're going to connect a server with self-signed certification, add `trusty` to `config`. This function is available for version >= `0.5.3` ```js RNFetchBlob.config({ trusty : true }) .then('GET', 'https://mysite.com') .then((resp) => { // ... }) ``` ## Changes | Version | | |---|---| | 0.6.0 | Add readFile and writeFile API for easier file access, also added Android download manager support. | | 0.5.8 | Fix #33 PUT request will always be sent as POST on Android | | 0.5.7 | Fix #31 #30 Xcode pre 7.3 build error | | 0.5.6 | Add support for IOS network status indicator. Fix file stream ASCII reader bug. | | 0.5.5 | Remove work in progress code added in 0.5.2 which may cause memory leaks. | | 0.5.4 | Fix #30 #31 build build error, and improve memory efficiency. | | 0.5.3 | Add API for access untrusted SSL server | | 0.5.2 | Fix improper url params bug [#26](https://github.com/wkh237/react-native-fetch-blob/issues/26) and change IOS HTTP implementation from NSURLConnection to NSURLSession | | 0.5.0 | Upload/download with direct access to file storage, and also added file access APIs | | 0.4.2 | Supports upload/download progress | | 0.4.1 | Fix upload form-data missing file extension problem on Android | | 0.4.0 | Add base-64 encode/decode library and API | | ~0.3.0 | Upload/Download octet-stream and form-data | ### Development If you're interested in hacking this module, check our [development guide](https://github.com/wkh237/react-native-fetch-blob/wiki/Home), there might be some helpful information. Please feel free to make a PR or file an issue.