nodejs-file-downloader

nodejs-file-downloader is a simple utility for downloading files. It hides the complexity of dealing with streams, redirects, paths and duplicate file names. Can automatically repeat failed downloads.

If you encounter any bugs or have a question, please don't hesitate to open an issue.

Installation

$ npm install nodejs-file-downloader

Table of Contents

• Examples
  • Basic
  • Get the progress of a download
  • Custom file name
  • Overwrite existing files
  • Hook into response
  • Repeat failed downloads automatically

Examples

Basic

Download a large file with default configuration

const Downloader = require('nodejs-file-downloader');

(async () => {//Wrapping the code with an async function, just for the sake of example.

    const downloader = new Downloader({     
      url: 'http://212.183.159.230/200MB.zip',//If the file name already exists, a new file with the name 200MB1.zip is created.     
      directory: "./downloads",//This folder will be created, if it doesn't exist.               
    })
    
    await downloader.download();//Downloader.download() returns a promise.

    console.log('All done');

})();    

 

Get the progress of a download

const Downloader = require('nodejs-file-downloader');

(async () => {

   const downloader = new Downloader({     
      url: 'http://212.183.159.230/200MB.zip',     
      directory: "./downloads/2020/May",//Sub directories will also be automatically created if they do not exist.  
      onProgress:function(percentage){//Gets called with each chunk.
           console.log('% ',percentage)   
      }         
    })    
    
    await downloader.download();   

})();    

 

Custom file name

Normally, nodejs-file-downloader "deduces" the file name, from the URL or the response headers. If you want to choose a custom file name, supply a config.fileName property.

  const downloader = new Downloader({     
      url: 'http://212.183.159.230/200MB.zip',     
      directory: "./downloads/2020/May", 
      fileName:'somename.zip'//This will be the file name.        
  }) 

 

Overwrite existing files

By default, nodejs-file-downloader uses config.cloneFiles = true, which means that files with an existing name, will have a number appended to them.

  const downloader = new Downloader({     
      url: 'http://212.183.159.230/200MB.zip',     
      directory: "./",  
      cloneFiles:false//This will cause the downloader to re-write an existing file.   
  }) 

 

Hook into response

If you need to get the underlying response, in order to decide whether the download should continue, or perform any other operations, use the onReponse hook.

  //The response object is a node response(http.IncomingMessage)
  function onResponse(response){
    //Now you can do something with the response, like check the headers
    if(response.headers['content-length'] > 1000000){
      console.log('File is too big!')
      return false;//If you return false, the download process is stopped, and downloader.download() is resolved.
    } 
    
    //Returning any other value, including undefined, will tell the downloader to proceed as usual.
  }

  const downloader = new Downloader({     
      url: 'http://212.183.159.230/200MB.zip',     
      directory: "./",
      onResponse        
  }) 

  await downloader.download()

 

Repeat failed downloads automatically

The program can repeat any failed downloads automatically. Only if the provided config.maxAttempts number is exceeded, an Error is thrown.

  const downloader = new Downloader({     
      url: 'http://212.183.159.230/200MB.zip',     
      directory: "./",
      maxAttempts:3,//Default is 1.
      onError:function(error){//You can also hook into each failed attempt.
        console.log('Error from attempt ',error)
      }        
  })   
  
  try {
    await downloader.dowload();
  } catch (error) {//If all attempts fail, the last error is thrown.
    console.log('Final fail',error)
  }