react-native-fetch-blob
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A module provides upload, download, and files access API. Supports file stream read/write for process large files.
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# react-native-fetch-blob [](https://badge.fury.io/js/react-native-fetch-blob) 
For latest document please visit our [github](https://github.com/wkh237/react-native-fetch-blob/)
A module provides upload, download, and files access API. Supports file stream read/write for process large files.
**Why do we need this**
At this moment, React Native does not support `Blob` object yet, so 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).
Hence you may getting into trouble in some use cases. For example, displaying an image on image server but the server requires a specific field(such as "Authorization") in headers or body, so you can't just pass the image uri to `Image` component because that will probably returns a 401 response. With help of this module, you can send a HTTP request with any headers, and decide how to handle the response/reqeust data. It can be just simply converted into BASE64 string, or store to a file directly so that you can read it by file stream or use it's path.
This module is designed to be a substitution of `blob`, there's a set of file access API including basic 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 Downloads App 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)
* [API](#user-content-api)
* [config](#user-content-config)
* [fetch](#user-content-fetchmethod-url-headers-bodypromisefetchblobresponse)
* [session](#user-content-sessionnamestringrnfetchblobsession)
* [base64](#user-content-base64)
* [fs](#user-content-fs)
* [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
```
**Android Access Permission to External storage (Optional)**
If you're going to access external storage (say, SD card storage), you might have to add the following line to `AndroidManifetst.xml`.
```diff
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.rnfetchblobtest"
android:versionCode="1"
android:versionName="1.0">
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW"/>
+ <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
+ <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
...
```
## 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 = <Image source={{ uri : Platform.OS === 'android' ? 'file://' : '' + res.path() }}/>
})
```
**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://` when the data comes from a file.
}, 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://` when the data comes from a file path
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 Downloads App Support
If you want to make a file in `External Storage` becomes visible in Picture, Misuc, or other built-in apps, you will have to use `Media Scanner`. To make this happend, use `scanFile` method in `fs`.
```js
RNFetchBlog
.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
})
```
If mime is null or undefined, then the mime type will be inferred from the file extension.
**Download Notification and Visibiliy in Download App (Android Only)**
<img src="img/android-notification1.png" width="256">
<img src="img/android-notification2.png" width="256">
If you want to download notification or make the stored file visible like the above. 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
- readStream
- writeStream
- unlink
- mkdir
- ls
- mv
- cp
- exists
- isDir
- lstat
- stat
- scanFile (Android Only)
See [fs chapter](#user-content-fs) 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(() => {
<Image source={{ uri : 'data:image/png,base64' + data }}
})
})
```
When use `writeStream`, the stream is also opened immediately, but you have to `write`, and `close` by yourself.
```js
RNFetchBlob.writeStream(
PATH_TO_FILE,
// encoding, should be one of `base64`, `utf8`, `ascii`
'utf8',
// should data append to existing content ?
true)
.then((ofstream) => {
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(() => { ... })
```
---
## API
### `config(options:RNFetchBlobConfig):fetch`
`0.5.0`
Config API was introduced in `v0.5.0` which provides some options for the `fetch` task.
see [RNFetchBlobConfig](#user-content-rnfetchblobconfig)
### `fetch(method, url, headers, body):Promise<FetchBlobResponse>`
`legacy`
Send a HTTP request uses given headers and body, and return a Promise.
#### method:`string` Required
HTTP request method, can be one of `get`, `post`, `delete`, and `put`, case-insensitive.
#### url:`string` Required
HTTP request destination url.
#### headers:`object` (Optional)
Headers of HTTP request, value of headers should be `stringified`, if you're uploading binary files, content-type should be `application/octet-stream` or `multipart/form-data`(see examples above).
#### body:`string | Array<Object>` (Optional)
Body of the HTTP request, body can either be a BASE64 string, or an array contains object elements, each element have 2 required property `name`, and `data`, and 1 optional property `filename`, once `filename` is set, content in `data` property will be consider as BASE64 string that will be converted into byte array later.
When body is a base64 string , this string will be converted into byte array in native code, and the request body will be sent as `application/octet-stream`.
### `fetch(...).progress(eventListener):Promise<FetchBlobResponse>`
`0.4.2`
Register on progress event handler for a fetch request.
#### eventListener:`(sendOrReceivedBytes:number, totalBytes:number)`
A function that triggers when there's data received/sent, first argument is the number of sent/received bytes, and second argument is expected total bytes number.
#### `session(name:string):RNFetchBlobSession`
TODO
### `base64`
`0.4.2`
A helper class simply uses [base-64](https://github.com/mathiasbynens/base64) for decode and encode BASE64 data.
```js
RNFetchBlob.base64.encode(data)
RNFetchBlob.base64.decode(data)
```
### `fs`
`0.5.0`
#### dirs
This constant is a hash map contains common used folders:
- DocumentDir
- CacheDir
- DCIMDir (Android Only)
- DownloadDir (Android Only)
- MusicDir (Android Only)
- PictureDir (Android Only)
- MovieDir (Android Only)
- RingtoneDir (Android Only)
```js
const dirs = RNFetchBlob.fs.dirs
console.log(dirs.DocumentDir)
console.log(dirs.CacheDir)
console.log(dirs.DCIMDir)
console.log(dirs.DownloadDir)
```
> If you're going to make downloaded file visible in Android `Downloads` app, please see [Show Downloaded File and Notification in Android Downloads App](#user-content-show-downloaded-file-and-notifiction-in-android-downloads-app).
### createFile(path, data, encoding):Promise
#### path:`string`
The path which this new file will be created.
#### data:`string` | `Array<number>`
Content of the new file, when `encoding` is `ascii`, this argument shoud be an array contains number 0~255.
#### encoding:`utf8` | `base64` | `ascii`
Encoding of content.
the following expressions are equivalent.
```js
const fs = RNFetchBlob.fs
const base64 = RNFetchBlob.base64
fs.createFile(NEW_FILE_PATH, 'foo', 'utf8')
fs.createFile(NEW_FILE_PATH, [102, 111, 111], 'ascii')
fs.createFile(NEW_FILE_PATH, base64.encode('foo'), 'base64')
```
### writeStream(path:string, encoding:string, append:boolean):Promise<WriteStream>
#### path:`string`
The path to the file the stream is writing to.
#### encoding:`utf8` | `base64` | `ascii`
Encoding of input data.
#### append:`boolean`(optional, default to `false`)
Will new data append after existing file or not.
Calling `writeStream` method will returns a Promise, which resolves a `RNFetchBlobWriteSteam` instance when stream opened successfully.
```js
// write utf8 data
RNFetchBlob.fs.writeStream(PATH_TO_WRITE, 'utf8')
.then((stream) => {
stream.write('foo')
return stream.close()
})
// write ASCII data
RNFetchBlob.fs.writeStream(PATH_TO_WRITE, 'ascii')
.then((stream) => {
// write char `f`
stream.write([102])
// write char `o`, `o`
stream.write([111,111])
return stream.close()
})
// write BASE64
RNFetchBlob.fs.writeStream(PATH_TO_WRITE, 'base64')
.then((stream) => {
stream.write(RNFetchBlob.base64.encode('foo'))
return stream.close()
})
```
#### readStream(path, encoding, bufferSize):Promise<ReadStream>
##### path:`string`
The path to the file the stream is reading from.
##### encoding:`string`
Encoding of the data.
##### bufferSize:`number`(optional)
Buffer size of read stream, default to `4096` and `4095`(when encoding is `base64`)
`readStream` returns a promise which will resolve `RNFetchBlobReadStream`.
```js
RNFetchBlob.fs.readStream(PATH_TO_READ, 'utf8')
.then((stream) => {
let data = ''
stream.open()
stream.onData((chunk) => {
chunk += data
})
stream.onEnd(() => {
console.log(data)
})
})
```
#### mkdir(path:string):Promise
Create a directory named `path`
```js
RNFetchBlob.fs.mkdir(PATH_TO_CREATE)
.then(() => { ... })
.catch((err) => { ... })
```
#### ls(path:string):Promise<Array<String>>
List files and directories in a `path`
```js
RNFetchBlob.fs.ls(PATH_TO_LIST)
// files will an array contains filenames
.then((files) => {
console.log(files)
})
```
#### mv(from:string, to:string):Promise
Move a file's location
```js
RNFetchBlob.fs.mv(FROM_PATH, TO_PATH)
.then(() => { ... })
.catch(() => { ... })
```
#### cp(src:string, dest:string):Promise
Copy a file.
```js
RNFetchBlob.fs.mv(SRC_PATH, DEST_PATH)
.then(() => { ... })
.catch(() => { ... })
```
#### exists(path:string):Promise<boolean>
Check if a file exist at `path`
```js
RNFetchBlob.fs.exists(PATH_OF_FILE)
.then((exist) => {
console.log(`file ${exist ? '' : 'not'} exists`)
})
.catch(() => { ... })
```
#### isDir(path:string):Promise<boolean>
Check the file at `path` is a directory or not. Resolves with `false` when the path is not a directory, or it does not exists.
```js
RNFetchBlob.fs.exists(PATH_OF_FILE)
.then((isDir) => {
console.log(`file is ${isDir ? '' : 'not'} a directory`)
})
```
#### unlink(path:string):Promise<boolean>
Delete a file at `path`
```js
RNFetchBlob.fs.unlink(path)
.then(() => { ... })
.catch((err) => { ... })
```
#### lstat(path:string):Promise<RNFetchBlobStat>
Get statistic data of files in a directory, the result data will be an array of [RNFetchBlobStat](#user-content-rnfetchblobstat).
```js
RNFetchBlob.fs.lstat(PATH_OF_A_FOLDER)
.then((stats) => {})
.catch((err) => {})
```
#### stat(path:string):Promise<RNFetchBlobStat>
Similar get statistic a data or a directory. the result data will be a [RNFetchBlobStat](#user-content-rnfetchblobstat).
```js
RNFetchBlob.fs.stat(PATH_OF_THE_TARGET)
.then((stats) => {})
.catch((err) => {})
```
#### scanFile(path:string):Promise (Androi Only)
Connect `Media Scanner` and scan the file. see [Android Media Scanner, and Downloads App Support](#user-content-android-media-scanner-and-downloads-app-support) chapter for more information.
---
## Types
### RNFetchBlobConfig
A set of configurations that will be injected into a `fetch` method, with the following properties.
#### fileCache:boolean
Set this property to `true` will makes response data of the `fetch` stored in a temp file, by default the temp file will stored in App's own root folder with file name template `RNFetchBlob_tmp${timestamp}`.
#### appendExt:string
Set this propery to change temp file extension that created by `fetch` response data.
#### path:string
When this property has value, `fetch` API will try to store response data in the path ignoring `fileCache` and `appendExt` property.
#### addAndroidDownloads:object (Android only)
This is an Android only property, it should be an object with the following properties :
- title : title of the file
- description : File description of the file.
- mime : MIME type of the file. By default is `text/plain`
- mediaScannable : A `boolean` value, see [Officail Document](https://developer.android.com/reference/android/app/DownloadManager.html#addCompletedDownload(java.lang.String, java.lang.String, boolean, java.lang.String, java.lang.String, long, boolean))
- notification : A `boolean` value decide whether show a notification when download complete.
### RNFetchBlobResponse
When `fetch` success, it resolve a `FetchBlobResponse` object as first argument. `FetchBlobResponse` object has the following methods (these method are synchronous, so you might take quite a performance impact if the file is big)
#### base64():string
returns base64 string of response data (done in native context)
#### json():object
returns json parsed object (done in js context)
#### text():string
returns decoded base64 string (done in js context)
#### path():string
returns file path if the response data is cached in file
#### session(name:string):RNFetchBlobSession
when the response data is cached in a file, this method adds the file into the session. The following usages are equivalent.
```js
RNFetchBlob.session('session-name').add(resp.path())
// or
resp.session('session-name')
```
### RNFetchBlobStat
Statistic data of a file, see the following sample object.
```js
{
// file name
filename : 'foo.png',
// folder of the file or the folder itself
path : '/path/to/the/file/wihout/file/name/',
// size in byte
size : 4901,
// `file` or `directory`
type : 'file',
// last modified timestamp
lastModified : 141323298
}
```
### RNFetchBlobSession
A `session` is an object that helps you manage files. It simply main a list of file path and let you use `dispose()`to delete files in this session once and for all.
#### add(path:string):RNFetchBlobSession
Add a file path to this session.
#### remove(path:string):RNFetchBlobSession
Remove a file path from this session (not delete the file).
#### list():Array<String>
Returns an array contains file paths in this session.
#### dispose():Promise
Delete all files according to paths in the session.
## Major Changes
| Version | |
|---|---|
| 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 | Fixe 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 |
### TODOs
* Customizable Multipart MIME type
* Improvement of file cache management API
### Development
If you're interested in hacking this module, check our [development guide](https://github.com/wkh237/react-native-fetch-blob/wiki/Development-Guide), there might be some helpful information.
Please feel free to make a PR or file an issue.