请求数和分片大小的上限改为可配置

Author: kscript

src/background.js

@@ -1,38 +1,48 @@
 import { configs } from './websites'
 import downloadZip from './download'
 
-chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
-  const getHeaders = (xhr) => {
-    const headers = {}
-    if (Array.isArray(message.responseHeaders)) {
-      message.responseHeaders.map(item => {
-        headers[item] = xhr.getResponseHeader(item)
-      })
-    }
-    return headers
-  }
-  const sendSuccess = (message, xhr) => {
-    sendResponse([null, message, getHeaders(xhr), xhr])
+const getHeaders = (xhr, responseHeaders) => {
+  const headers = {}
+  if (Array.isArray(responseHeaders)) {
+    responseHeaders.map(item => {
+      headers[item] = xhr.getResponseHeader(item)
+    })
   }
-  const sendError = (error, xhr) => {
-    sendResponse([error, null, getHeaders(xhr), xhr])
+  return headers
+}
+
+const sendCallback = (sendResponse, responseHeaders) => {
+  return {
+    sendSuccess (message, xhr) {
+      sendResponse([null, message, getHeaders(xhr, responseHeaders), xhr])
+    },
+    sendError (error, xhr) {
+      sendResponse([error, null, getHeaders(xhr, responseHeaders), xhr])
+    }
   }
-  if (/(get|post)/i.test(message.type)) {
+}
+
+chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
+  const { type, responseHeaders } = message
+  const { url, data, dataType, callback } = message
+  const { fileName, files, options } = message
+  const { sendSuccess, sendError } = sendCallback(sendResponse, responseHeaders)
+  if (/(get|post)/i.test(type)) {
     ajax({
-      url: message.url,
-      method: message.type,
-      data: message.data,
-      dataType: message.dataType,
+      url,
+      method: type,
+      data,
+      dataType,
       success (data, xhr) {
-        if (/text|blob/i.test(message.dataType)) {
+        if (/text|blob/i.test(dataType)) {
           sendSuccess(data, xhr)
         } else {
-          const obj = message.dataType === 'text' ? data : JSON.parse(data)
-          const result = /^json$/i.test(message.dataType) ? {
-            callback: message.callback,
+          const obj = dataType === 'text' ? data : JSON.parse(data)
+          const result = /^json$/i.test(dataType) ? {
+            callback: noop(callback),
             data: obj
           } : data
-          if (typeof message.callback === 'string' && message.callback.length) {
+          if (typeof callback === 'string' && callback) {
             sendSuccess(result, xhr)
           } else {
             sendSuccess(obj, xhr)
@@ -43,8 +53,8 @@ chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
         sendError(error, xhr)
       }
     })
-  } else if (message.type === 'download') {
-    downloadZip(message.fileName, message.files)
+  } else if (type === 'download') {
+    downloadZip(fileName, files, options)
   }
   return true
 })

src/download.js

@@ -2,10 +2,17 @@ import md5 from 'md5'
 import JSZip from 'jszip'
 import FileSaver from 'jszip/vendor/FileSaver'
 
-// 每段数量上限
-export const partLimit = 1e3
-// 同时请求数上限
-export const requestLimit = 5
+const defaultOptions = {
+  partLimit: 1e3,
+  requestLimit: 5
+}
+
+const options = Object.assign({}, defaultOptions)
+
+export const mergeOptions = (newOptions) => {
+  return Object.assign(options, defaultOptions, newOptions instanceof Object ? newOptions : {})
+}
+
 
 export const noop = (func, defaultFunc) => {
   return typeof func === 'function' ? func : typeof defaultFunc === 'function' ? defaultFunc : () => {}
@@ -59,13 +66,13 @@ export const fetchBlobFile = (file) =>{
   })
 }
 
-export const partTask = (items, handler, num = requestLimit) => {
+export const partTask = (items, handler, limit) => {
   let index = 0
   let list = items.slice(0)
   let queue = Promise.resolve()
   const result = []
   while (list.length) {
-    const current = list.splice(0, num)
+    const current = list.splice(0, limit)
     const currentIndex = index++
     queue = queue.then(() => {
       return new Promise((resolve) => {
@@ -79,7 +86,7 @@ export const partTask = (items, handler, num = requestLimit) => {
   return queue
 }
 
-export const partRequest = (fileName, files) => {
+export const partRequest = (fileName, files, { requestLimit } = options) => {
   const zip = new JSZip()
   const handler = (files) => files.map(file => fetchBlobFile(file, zip).then(blob => {
     zip.file(file.name, blob)
@@ -99,18 +106,18 @@ export const partRequest = (fileName, files) => {
   })
 }
 
-export const partDownload = (fileName, files) => {
+export const partDownload = (fileName, files, { partLimit } = options) => {
   const count = ~~(files.length / partLimit)
   return partTask(files, (files, index) => {
     const partMame = count >= 1 ? '-p' + (index + 1) + '-' + count : ''
     const name = fileName + partMame + '.zip'
-    return [partRequest(name, files)]
+    return [partRequest(name, files, options)]
   }, partLimit)
 }
 
-export const downloadZip = (fileName, files) => {
+export const downloadZip = (fileName, files, options = {}) => {
   fileName = fileName || md5(files.map(item => item.downloadUrl).join('|'))
-  return partDownload(fileName, files)
+  return partDownload(fileName, files, mergeOptions(options))
 }
 
 export default downloadZip