emuload v1.3.19

Speed up download of a single file with multiple HTTP GET connections running in parallel

Class: Download

Download is an EventEmitter.

start(url, options)

• url <string> Url of file to be downloaded
• options <StartOptions> Download options (Optional)
  • numOfConnections <number> Number of HTTP GET connections to use for performing the download (Optional)
  • throttleRate <number> Delay the 'data' event (Optional)
  • saveDirectory <string> Directory to save the downloaded file (Optional)
  • fileName <string> Set name of the downloaded file (Optional)
  • headers <Object> Set custom HTTP headers (Optional)

Starts the download operation from the url.

Multiple HTTP GET connections will only be used if the target server supports partial requests. If the target server does not support partial requests, only a single HTTP GET connection will be used regardless of what the numOfConnections is set to.

If the numOfConnections parameter is not provided, a single connection will be used.

If the saveDirectory parameter is provided, the downloaded file will be saved to saveDirectory.

If the throttleRate is provided, the data event will fire after every throttleRate milisecond.

If the fileName parameter is provided, the downloaded file will be renamed to fileName.

If the fileName parameter is not provided, the downloaded file will maintain its original file name.

If the headers parameter is provided, the headers will be included in the HTTP request.

Event: 'error'

• err <Error> Emitted error

Event: 'data'

• data <Object> Contains the current download progress and other metadata

Event: 'end'

• Download complete

output is the location of the saved file if the saveDirectory parameter is provided.

Example

const Download = require("emuload");

new Download()
  .start("https://homepages.cae.wisc.edu/~ece533/images/cat.png", {
    numOfConnections: 5,
    saveDirectory: __dirname,
    filename: "cat.png",
    throttleRate: 100,
  })
  .on("error", (err) => {
    // handle error here
  })
  .on("data", (data, offset) => {
    // get current download data here
  })
  .on("end", () => {
    // download complete
  });