Based on the other answers above and some subtle issues, here is my attempt. Check the file does not exist before hitting the network by using fs. Only create the fs. This reduces the amount of fs. Even on a OK we can still possibly reject due to an EEXIST file already exists imagine another process created the file whilst we were doing network calls.
Recursively call download if you get a Moved Permanently or Found Moved Temporarily redirect following the link location provided in the header.
The issue with some of the other answers recursively calling download was that they called resolve download instead of download This way the nested chain of promises resolve in the correct order. It might seem cool to clean up the temp file asynchronously, but I chose to reject only after that completed too so I know that everything start to finish is done when this promise resolves or rejects.
Josh Peak Josh Peak 4, 4 4 gold badges 33 33 silver badges 48 48 bronze badges. You shouldn't waste resources doing the download if the destination file already exists. Do the check first if possible. Phil Really good point. I have updated the example with an earlier guard check before falling into the recursive networking calls but left the success file handling code the same.
This short circuit guard statement should save some time in this case now. Vince Yuan's code is great but it seems to be something wrong. But we don't check the result if callback callback err. Feel Physics Feel Physics 2, 4 4 gold badges 23 23 silver badges 36 36 bronze badges. I prefer request because you can use both http and https with it. Looks like Request has been deprecated github. No new changes are expected to land.
In fact, none have landed for some time. Wai Ha Lee 7, 61 61 gold badges 56 56 silver badges 85 85 bronze badges. Idan Dagan Idan Dagan 7, 3 3 gold badges 28 28 silver badges 38 38 bronze badges. Roman Podlinov Roman Podlinov Very clean, thank you. What do the flags 'wx' do when you're creating the writeStream?
It is returning garbage character if file name is other than ascii like if filename is in japanese. Do you think ajax-request is not a third party library? Download using promise, which resolve a readable stream.
The questions was specific to not include third party modes : — David Gatti. If you are using express use res. Using the http2 Module I saw answers using the http , https , and request modules.
I'd like to add one using yet another native NodeJS module that supports either the http or https protocol: Solution I've referenced the official NodeJS API, as well as some of the other answers on this question for something I'm doing. Rik Rik 3 3 silver badges 8 8 bronze badges. Is this backward compatible? Works everywhere or only for http2? Neil I'm assuming you are asking if http2 is backward compatible with http1.
Because http2 improves framing; adding binary compression, the ability to push from server to client, and simultaneous connections - it is absolutely required that both server and client know the implementation this allows abstraction of implementation from the application too. Good news is that all major browsers have supported http2 since about - and Node as a client does too. Node, Nginx, and Apache offer it server side - so most use cases are covered. Its a vast improvement.
Thanks for the reply Rik — Neil. Without library it could be buggy just to point out. Here my suggestion: Call system tool like wget or curl use some tool like node-wget-promise which also very simple to use. Geng Jiawen Geng Jiawen 7, 2 2 gold badges 41 41 silver badges 36 36 bronze badges.
Writing my own solution since the existing didn't fit my requirements. Alex Pilugin Alex Pilugin 2 2 gold badges 9 9 silver badges 30 30 bronze badges. Pankaj Pankaj 1 1 gold badge 3 3 silver badges 9 9 bronze badges. Frankenmint Frankenmint 1, 1 1 gold badge 17 17 silver badges 30 30 bronze badges.
Like: res. Jeremy M. Yin Yin 9. I suggest you to use res. Mehrzad Tejareh 4 4 silver badges 18 18 bronze badges. Check out download NPM page for more information. I'm sending out an occasional email with the latest programming tutorials.
Drop your email in the box below and I'll send new stuff straight into your inbox! Nathan Sebhastian is a software engineer with a passion for writing tech tutorials. Learn JavaScript and other web development technology concepts through easy-to-understand explanations written in plain English. How to download a file using NodeJS without any extra package Download a file to your filesystem using NodeJS without any extra package Posted on June 26, You can download a file an image, a text, or any kind of file and save it to your filesystem using NodeJS built-in https and fs module.
Level up your programming skills I'm sending out an occasional email with the latest programming tutorials. About Nathan Sebhastian is a software engineer with a passion for writing tech tutorials.
This method of downloading looks the most simple from coding point of view. Why exec and not spawn? Because we just want wget to tell us if the work was done properly or not, we are not interested in buffers and streams. We are making wget do all the dirty work of making request, handling data, and saving the file for us. As you might have guessed, this method is the fastest among the three methods I described. So now the question is - which method is the best? The answer - whatever suits your need.
The wget method is probably the best is you want to save the files to the local disk, but certainly not if you want to send those files as a response to a current client request; for something like that you would need to use a stream. All the three methods have multiple options, you choice will ultimately depend on what your needs are. How to publish a Node. If you don't know how to create one, read "Node.
Assuming you ar How to create custom Express.
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