react-native-fetch-blob/class/RNFetchBlobWriteStream.js

A module provides upload, download, and files access API. Supports file stream read/write for process large files.

// Copyright 2016 wkh237@github. All rights reserved.
// Use of this source code is governed by a MIT-style license that can be
// found in the LICENSE file.

import {
 NativeModules,
 DeviceEventEmitter,
 NativeAppEventEmitter,
} from 'react-native'

const RNFetchBlob = NativeModules.RNFetchBlob
const emitter = DeviceEventEmitter

export default class RNFetchBlobWriteStream {

  id : string;
  encoding : string;
  append : bool;

  constructor(streamId:string, encoding:string, append:string) {
    this.id = streamId
    this.encoding = encoding
    this.append = append
  }

  write(data:string) {
    return new Promise((resolve, reject) => {
      try {
        let method = this.encoding === 'ascii' ? 'writeArrayChunk' : 'writeChunk'
        if(this.encoding.toLocaleLowerCase() === 'ascii' && !Array.isArray(data)) {
            reject('ascii input data must be an Array')
            return
        }
        RNFetchBlob[method](this.id, data, (error) => {
          if(error)
            reject(error)
          else
            resolve()
        })
      } catch(err) {
        reject(err)
      }
    })
  }

  close() {
    return new Promise((resolve, reject) => {
      try {
        RNFetchBlob.closeStream(this.id, () => {
          resolve()
        })
      } catch (err) {
        reject(err)
      }
    })
  }

}