Refactor JS interface and add file write stream API

src/fs.js

@@ -0,0 +1,281 @@
+/**
+ * @name react-native-fetch-blob-fs
+ * @author wkh237
+ * @version 0.1.0
+ * @flow
+ */
+
+import {
+  NativeModules,
+  DeviceEventEmitter,
+  NativeAppEventEmitter,
+} from 'react-native'
+import type {
+  RNFetchBlobNative,
+  RNFetchBlobConfig,
+  RNFetchBlobStream
+} from './types'
+
+const RNFetchBlob:RNFetchBlobNative = NativeModules.RNFetchBlob
+const emitter = DeviceEventEmitter
+
+// session table
+let sessions = {}
+
+/**
+ * Get path of system directories.
+ * @return {object} Map contains PictureDir, MovieDir, DocumentDir, CacheDir,
+ * MusicDir, and DCIMDir, some directory might not be supported by platform.
+ */
+function getSystemDirs() {
+  return new Promise((resolve, reject) => {
+    try {
+      RNFetchBlob.getEnvironmentDirs((...dirs) => {
+        let [PictureDir, MovieDir, DocumentDir, CacheDir, MusicDir, DCIMDir] = [...dirs]
+        resolve({PictureDir, MovieDir, DocumentDir, CacheDir, MusicDir, DCIMDir})
+      })
+    } catch(err) {
+      reject(err)
+    }
+  })
+}
+
+/**
+ * Get a file cache session
+ * @param  {[type]} name:string [description]
+ * @return {[type]}             [description]
+ */
+function session(name:string):RNFetchBlobSession {
+  let s = sessions[name]
+  if(s)
+    return new RNFetchBlobSession(name)
+  else {
+    sessions[name] = []
+    return new RNFetchBlobSession(name, [])
+  }
+}
+
+function writeStream(
+  path:string,
+  encoding:'utf8' | 'ascii' | 'base64',
+  callback:(streamId:string) => void
+):Promise<WriteStream> {
+  if(!path)
+    throw Error('RNFetchBlob could not open file stream with empty `path`')
+  encoding = encoding || 'base64'
+  return new Promise((resolve, reject) => {
+    RNFetchBlob.writeStream(path, encoding || 'base64', (streamId:string) => {
+      resolve(new WriteStream(streamId))
+    })
+  })
+}
+
+/**
+ * Create file stream from file at `path`.
+ * @param  {String} path   The file path.
+ * @param  {String} encoding Data encoding, should be one of `base64`, `utf8`, `ascii`
+ * @param  {String} bufferSize Size of stream buffer.
+ * @return {RNFetchBlobStream} RNFetchBlobStream stream instance.
+ */
+function readStream(
+  path:string,
+  encoding:'utf8' | 'ascii' | 'base64',
+  bufferSize?:?number
+):RNFetchBlobStream {
+
+  if(!path)
+    throw Error('RNFetchBlob could not open file stream with empty `path`')
+
+  let stream:RNFetchBlobStream = {
+    onData : function(fn) {
+      this._onData = fn
+    },
+    onError : function(fn) {
+      this._onError = fn
+    },
+    onEnd : function(fn) {
+      this._onEnd = fn
+    },
+  }
+
+  // register for file stream event
+  let subscription = emitter.addListener(`RNFetchBlobStream+${path}`, (e) => {
+
+    let {event, detail} = e
+    if(stream._onData && event === 'data')
+      stream._onData(detail)
+    else if (stream._onEnd && event === 'end') {
+      stream._onEnd(detail)
+    }
+    else {
+      stream._onError(detail)
+    }
+    // when stream closed or error, remove event handler
+    if (event === 'error' || event === 'end') {
+      subscription.remove()
+    }
+  })
+
+  RNFetchBlob.readStream(path, encoding, bufferSize || 0)
+  return stream
+
+}
+
+function mkdir(path:string):Promise {
+
+  return new Promise((resolve, reject) => {
+    RNFetchBlob.mkdir(path, (err, res) => {
+      if(err)
+        reject(err)
+      else
+        resolve(res)
+    })
+  })
+
+}
+
+function cp(path:string, dest:string):Promise<boolean> {
+  return new Promise((resolve, reject) => {
+    RNFetchBlob.cp(path, dest, (err, res) => {
+      if(err)
+        reject(err)
+      else
+        resolve(res)
+    })
+  })
+}
+
+function mv(path:string, dest:string):Promise<boolean> {
+  return new Promise((resolve, reject) => {
+    RNFetchBlob.ls(path, dest, (err, res) => {
+      if(err)
+        reject(err)
+      else
+        resolve(res)
+    })
+  })
+}
+
+function ls(path:string):Promise<Array<String>> {
+  return new Promise((resolve, reject) => {
+    RNFetchBlob.ls(path, (err, res) => {
+      if(err)
+        reject(err)
+      else
+        resolve(res)
+    })
+  })
+}
+
+/**
+ * Remove file at path.
+ * @param  {string}   path:string Path of target file.
+ * @return {Promise}
+ */
+function unlink(path:string):Promise {
+  return new Promise((resolve, reject) => {
+    RNFetchBlob.unlink(path, (err) => {
+      if(err)
+        reject(err)
+      else
+        resolve()
+    })
+  })
+}
+
+/**
+ * Session class
+ * @class RNFetchBlobSession
+ */
+class RNFetchBlobSession {
+
+  add : (path:string) => RNFetchBlobSession;
+  remove : (path:string) => RNFetchBlobSession;
+  dispose : () => Promise;
+  list : () => Array<string>;
+  name : string;
+
+  constructor(name:string, list:Array<string>) {
+    this.name = name
+    if(!sessions[name]) {
+      if(Array.isArray(list))
+      sessions[name] = list
+      else
+      sessions[name] = []
+    }
+  }
+
+  add(path:string):RNFetchBlobSession {
+    sessions[this.name].push(path)
+    return this
+  }
+
+  remove(path:string):RNFetchBlobSession {
+    let list = sessions[this.name]
+    for(let i in list) {
+      if(list[i] === path) {
+        sessions[this.name].splice(i, 1)
+        break;
+      }
+    }
+    return this
+  }
+
+  list():Array<string> {
+    return sessions[this.name]
+  }
+
+  dispose():Promise {
+    return new Promise((resolve, reject) => {
+      RNFetchBlob.removeSession(sessions[this.name], (err) => {
+        if(err)
+          reject(err)
+        else {
+          delete sessions[this.name]
+          resolve()
+        }
+      })
+    })
+  }
+
+}
+
+class WriteStream {
+
+  id : string;
+  encoding : string;
+
+  constructor(streamId:string, encoding:string) {
+    this.id = streamId
+    this.encoding = encoding
+  }
+
+  write() {
+    return new Promise((resolve, reject) => {
+      try {
+        RNFetchBlob.writeChunk(this.id, data, this.encoding, () => {
+          resolve()
+        })
+      } catch(err) {
+        reject(err)
+      }
+    })
+  }
+
+  close() {
+    return new Promise((resolve, reject) => {
+      try {
+        RNFetchBlob.closeStream(this.id, () => {
+          resolve()
+        })
+      } catch (err) {
+        reject(err)
+      }
+    })
+  }
+
+}
+
+export default {
+  RNFetchBlobSession, unlink, mkdir, session, ls, readStream, getSystemDirs, mv, cp
+}

src/index.js

@@ -10,17 +10,29 @@ import {
   DeviceEventEmitter,
   NativeAppEventEmitter,
   Platform,
+  AsyncStorage,
 } from 'react-native'
 import type {
   RNFetchBlobNative,
   RNFetchBlobConfig,
   RNFetchBlobStream
 } from './types'
+import fs from './fs'
 import base64 from 'base-64'
+const {
+  RNFetchBlobSession,
+  getSystemDirs,
+  readStream,
+  unlink,
+  mkdir,
+  session,
+  ls,
+  mv,
+  cp
+} = fs
 
 const emitter = DeviceEventEmitter
 const RNFetchBlob:RNFetchBlobNative = NativeModules.RNFetchBlob
-const pathPrefix = Platform.OS === 'android' ? 'file://' : ''
 
 // register message channel event handler.
 emitter.addListener("RNFetchBlobMessage", (e) => {
@@ -44,26 +56,6 @@ if(!RNFetchBlob || !RNFetchBlob.fetchBlobForm || !RNFetchBlob.fetchBlob) {
   )
 }
 
-/**
- * Get path of system directories.
- * @return {object} Map contains PictureDir, MovieDir, DocumentDir, CacheDir,
- * MusicDir, and DCIMDir, some directory might not be supported by platform.
- */
-function getSystemDirs() {
-  return new Promise((resolve, reject) => {
-    try {
-      RNFetchBlob.getEnvironmentDirs((...dirs) => {
-        let [PictureDir, MovieDir, DocumentDir, CacheDir, MusicDir, DCIMDir] = [...dirs]
-        console.log({PictureDir, MovieDir, DocumentDir, CacheDir, MusicDir, DCIMDir})
-        resolve({PictureDir, MovieDir, DocumentDir, CacheDir, MusicDir, DCIMDir})
-      })
-    } catch(err) {
-      reject(err)
-    }
-  })
-
-}
-
 /**
  * Calling this method will inject configurations into followed `fetch` method.
  * @param  {RNFetchBlobConfig} options
@@ -117,17 +109,21 @@ function fetch(...args:any):Promise {
     })
 
     let req = RNFetchBlob[nativeMethodName]
-    req(options, taskId, method, url, headers || {}, body, (err, ...data) => {
+    req(options, taskId, method, url, headers || {}, body, (err, data) => {
 
       // task done, remove event listener
       subscription.remove()
       if(err)
-        reject(new Error(err, ...data))
+        reject(new Error(err, data))
       else {
         let respType = 'base64'
-        if(options.path || options.fileCache)
+        // response data is saved to storage
+        if(options.path || options.fileCache) {
           respType = 'path'
-        resolve(new FetchBlobResponse(taskId, respType, ...data))
+          if(options.session)
+            session(options.session).add(data)
+        }
+        resolve(new FetchBlobResponse(taskId, respType, data))
       }
     })
 
@@ -144,73 +140,6 @@ function fetch(...args:any):Promise {
 
 }
 
-/**
- * Create file stream from file at `path`.
- * @param  {String} path   The file path.
- * @param  {String} encoding Data encoding, should be one of `base64`, `utf8`, `ascii`
- * @param  {String} bufferSize Size of stream buffer.
- * @return {RNFetchBlobStream} RNFetchBlobStream stream instance.
- */
-function openReadStream(
-  path:string,
-  encoding:'utf8' | 'ascii' | 'base64',
-  bufferSize?:?number
-):RNFetchBlobStream {
-
-  if(!path)
-    throw Error('RNFetchBlob could not open file stream with empty `path`')
-
-  let stream:RNFetchBlobStream = {
-    onData : function(fn) {
-      this._onData = fn
-    },
-    onError : function(fn) {
-      this._onError = fn
-    },
-    onEnd : function(fn) {
-      this._onEnd = fn
-    },
-  }
-
-  // register for file stream event
-  let subscription = emitter.addListener(`RNFetchBlobStream+${path}`, (e) => {
-
-    let {event, detail} = e
-    if(stream._onData && event === 'data')
-      stream._onData(detail)
-    else if (stream._onEnd && event === 'end') {
-      stream._onEnd(detail)
-    }
-    else {
-      stream._onError(detail)
-    }
-    // when stream closed or error, remove event handler
-    if (event === 'error' || event === 'end') {
-      subscription.remove()
-    }
-  })
-
-  RNFetchBlob.readStream(path, encoding, bufferSize || 0)
-  return stream
-
-}
-
-/**
- * Remove file at path.
- * @param  {string}   path:string Path of target file.
- * @return {Promise}
- */
-function unlink(path:string):Promise {
-  return new Promise((resolve, reject) => {
-    RNFetchBlob.unlink(path, (err) => {
-      if(err)
-        reject(err)
-      else
-        resolve()
-    })
-  })
-}
-
 /**
  * RNFetchBlob response object class.
  */
@@ -280,6 +209,14 @@ class FetchBlobResponse {
         return this.data
       return null
     }
+    this.session = (name) => {
+      if(this.type === 'path')
+        return session(name).add(this.data)
+      else {
+        console.warn('only file paths can be add into session.')
+        return null
+      }
+    }
     /**
      * Start read stream from cached file
      * @param  {String} encoding Encode type, should be one of `base64`, `ascrii`, `utf8`.
@@ -288,7 +225,7 @@ class FetchBlobResponse {
      */
     this.readStream = (encode: 'base64' | 'utf8' | 'ascii'):RNFetchBlobStream | null => {
       if(this.type === 'path') {
-        return openReadStream(this.data, encode)
+        return readStream(this.data, encode)
       }
       else {
         console.warn('RNFetchblob', 'this response data does not contains any available stream')
@@ -307,5 +244,5 @@ function getUUID() {
 }
 
 export default {
-  fetch, base64, config, getSystemDirs, readStream, unlink
+  fetch, base64, config, getSystemDirs, readStream, unlink, session, ls, mkdir, mv, cp
 }

src/types.js

@@ -2,7 +2,8 @@
 type RNFetchBlobConfig = {
   fileCache : bool,
   path : string,
-  appendExt : string
+  appendExt : string,
+  session : string
 };
 
 type RNFetchBlobNative = {
@@ -34,7 +35,9 @@ type RNFetchBlobNative = {
   // get system folders
   getEnvironmentDirs : (dirs:any) => void,
   // unlink file by path
-  flush : (path:string) => void
+  unlink : (path:string, callback: (err:any) => void) => void,
+  removeSession : (paths:Array<string>, callback: (err:any) => void) => void,
+  ls : (path:string, callback: (err:any) => void) => void,
 };
 
 type RNFetchBlobStream = {