Michelle Tilley Michelle Tilley k 39 39 gold badges silver badges bronze badges. I got the following console output when I ran this script: node. Does this code close the file properly when the script ends or would it lose data?
This depends upon the req url type if you are requesting https you must use https otherwise it will throw error. EthanKeiley why do you say that it isn't closed properly? By default createWriteStream will set autoClose to true and readable. Show 14 more comments. Don't forget to handle errors!
The following code is based on Augusto Roman's answer. But we don't check the result if cb cb err. Vince Yuan Vince Yuan VinceYuan the callback is confusing me. What would I place as the cb argument? Abdul Sounds like you are very new to node. Take a look at this tutorial: tutorialspoint. Abdul maybe it would be good if you share with the rest of the class what you have figured out? Is there a way to see the speed of the download?
Show 7 more comments. Kelvin Omereshone 2 2 silver badges 11 11 bronze badges. Abdul You specify the callback with a function only if you need to do something when the file has been successfully fetched.
It would be good to check the status code before saving: response. But we don't check the result return cb err. Buzut Buzut 4, 4 4 gold badges 41 41 silver badges 50 50 bronze badges. The request module just works straight for HTTPs. S Ventura. It's more error prone without a doubt. Anyway, in any case where using request module is an option, I'd advise it as it's way higher level and thus, easier and efficient.
Alex, nope, this is an error message and there's a return. So if response. Thank you for showing example using request module. Show 3 more comments. MikeL 5, 38 38 silver badges 41 41 bronze badges. Augusto Roman Augusto Roman 6 6 silver badges 4 4 bronze badges. What for are you storing request into a variable?
You are right, there is no need to save the request, its not used anyway. That's what you mean? Yes, I think that's what polkovnikov. Per default the fs. Bjarke Pjedsted Bjarke Pjedsted 4 4 silver badges 8 8 bronze badges.
Two comments on this: 1 it should probably reject Error objects, not strings, 2 fs. This works great! No errors popped up but the. Removing the logic for the flag fixed it. Just wanted to point that out if someone had the issues with the approach.
Is there a memory leak in this answer: stackoverflow. You can add timeout like I did in http. The memory leak is only if the file take too long to be downloaded.
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.
This is because the hosting environment needs the complete information about the page from the URL, and then accordingly it discovers the page on the server. In Node. In this article, we will create a Node. Our code will then read the request URL and based on it, the response will be sent back. Node Tools for Visual Studio. The implementation here uses Visual Studio Code. Step 1: Create a folder on the drive e. In this folder add a new folder of the name Scripts.
We will be using this to store our application files. Open Visual Studio Code. Once the folder is opened, the option for creating a new file will be displayed to the right, as shown in the following image. Select the Script folder and click on the new file icon as shown in the following image. This will provide a blank textbox where you create a new file name as app.
Add the following markup in it:. The above code performs the following operations. Note: Comments on each line match with the numbers used in the following points. Since we need to create web server for http messaging, we need http module. We will be reading the html file using File IO, for that we need to load fs module. If the file is not read successfully, the response with Http Status as Not Found will be sent for the request message.
Browser will automatically download the file. If this header will present in response then browser will force fully download the file. We can also specify the file name in this header. Another header is Content-Type , this contains the type of content or file type. Now run server. Your file will be download. In Express. Here [] indicates the optional parameter. First parameter is. We can use both relative as well as absolute path.
Another parameter is filename and the last parameter is function we will use to handle errors. NodeJs download file example — output. There are so many npm packages are available for this. Based on your requirements you can use them. Here, I used downloadjs. In this case server send the response in form of stream or blob likewise.
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