Tons of files get downloaded from the internet every day ranging from binary files like applications, images, videos, and audios to files in plain text.
The server then returns a response containing the content of the file and some instructional headers specifying how the client should download the file.
In this diagram, the green line shows the flow of the request from the client to the server over HTTP. The orange line shows the flow of the response from the server back to the client. Though the diagram indicates the communication flow, it does not explicitly show what the request from the client looks like or what the response from the server looks like.
Here is what the response from the server could possibly look like:. The desired behavior is that the image should be downloaded not displayed. To inform the client that the content of the resource is not meant to be displayed, the server must include an additional header in the response. The Content-Disposition header is the right header for specifying this kind of information.
However, it can be interpreted by several HTTP clients including web browsers. This header provides information on the disposition type and disposition parameters. The disposition type is usually one of the following:. The disposition parameters are additional parameters that specify information about the body part or file such as filename, creation date, modification date, read date, size, etc.
Now the server enforces a download of the GIF image. Most HTTP clients will prompt the user to download the resource content when they receive a response from a server like the one above.
The scenario described above is not feasible in web applications. For example, click to save a photo or download a report. Anchor elements are useful for adding hyperlinks to other resources and documents from an HTML document. The URL of the linked resource is specified in the href attribute of the anchor element.
In HTML 5, a new download attribute was added to the anchor element. The download attribute can be given a valid filename as its value. However, the user can still modify the filename in the save prompt that pops-up.
There are a few noteworthy facts about the behavior of the download attribute:. There are now Web APIs that can be used to programmatically:.
In this section, we will examine how we can programmatically generate content using Web APIs on the browser. Here is a breakdown of what we are about to do:. Here is what the CSV generation script could look like:. The code snippet simply logs the resulting CSV string to the console. First, we define a squareImages filter function for filtering images in the collection with equal width and height.
The problem on the client side is that the file is being downloaded into the response object browser's cache memory I suppose, as a temporary file instead of the PC's hard drive. The file size is really large and there's not enough space on the gadget's hard drive to create it there and give a link for GET request. Right now I've written my code in Angular, but the language doesn't really matter. I'd like to understand how the browser handles the situation. And I'm sure the browser does something with the received request too before passing it to the piece of code which performed the request.
What happens then to the waiting HTTP request if the packets are "stolen" by the browser? Instead of just receiving that file in the temporary memory of the browser I would like to save the file directly on hard drive.
But naturally the browser prevents the direct access to the users computer so I can't write it there. So how do I pass the byte stream for the browser to handle and save into a file? Ok, I have solved the problem. So if you send a file request yourself to the server from your javascript code the browser will just pass the received response directly to your response object, but you can't store it on the hard drive without some external browser supported tools.
Meaning that if you're expecting a file with the size of 5GB it will fail for being too large to be received inside the response object. Instead what you have to do is to trigger the download in another way. What I did in my code is that I built a hidden. Which looks like. This way you can pass the request to be done by your browser so that then the response will be also handled by the browser. This is the crucial difference between doing the request yourself or by the browser.
If you do the request yourself then the browser won't download the object but you will receive it yourself to do something with it. I would also like to request that you take a look at Download Ninja and compare it to others. Please let me know if you would like any information or have any comments :. I have been using Freedownloadmanager for more than a decade now and I firmly recommend it too. Flashget has started bundling unnecessary toolbars in its software in the last years.
Thanks for the article. It works perfectly and I finaly get the Gegeek toolkit. The quality of this article is unbecoming my expectations from a ghack article. You should take the time to structure your article and review it thoroughly before you post.
An open frank no judgmental assessment of various computer programs, sites and hardware. That seems a bit rude. Only two things were noted: 1 A number of users had problems downloading a large file from a site; 2 The users needed some type of understanding about why they were encountering the problem and several solutions to solve the problem.
The author listed four requirements for the programs he was introducing. The author warned, again as he always does , that many of the programs may have adware bundled within the setup file and how to avoid possible inadvertent installation of an unwanted program.
They have accumulated several serial numbers that have been used in giveaway promotions. I have tried two of them and IDM successfully registered with both. FDM has an option within the program to create a portable version.
The download available from FDM is an installer and has no options to create it as portable during install, either. While most of the portables I use are direct, some are from PortableApps. While I could create a FDM portable version by installing it first..
I do NOT want to install stuff, then create a portable version and then uninstall it — FDM, IMO, should perhaps simply just provide a portable zipped version or a portable option in the installer which I ran thru and it includes adding registry entries. However, its their software, they can do what they like with it. Or you can just use universal extractor or zip for that matter if I remember correctly , and unzip the setup exe.
I usually use The Free Download Manager. Sometimes I use wget to continue downloads that get interrupted in firefox. Free Download Manager logs your download activity to their own server ip A few years back I remember trying FDM and noticed thru currports that several strange ip addresses kicked in when downloading.
So, I decided to give it a whirl again with the current FDM version.. I then used Fiddle to check out more on what was happening. The IP Porn sites are hosted, and the somewhat popular GOTD is hosted by the company. There is activity to a php page and server before that page gets loaded that is hidden unless you track the activity of FDM.
In this case, you use the program and the price is data collection it seems. When I opened FDM, no outbound traffic was observed. Load the url and look at it. Note: I have automatic updates turned off, I do not use the mirrors option, I do have "display opinions when downloading" checked, I do not check downloads before downloading if they are malicious..
No other outbound connections are made except the actual downloads. No information about what I am doing is sent. Also note that the address I captured FDM contacting is. Mozilla had one of these. The -c parameter should be mentioned to continue an interrupted download as should be the wgetrc file. DownThemAll for Firefox is the best of the best. A free Firefox add-on, it supports multi-threaded downloads, pause and resume, and can download all media pictures, MP3s, etc.
Used to use free download manager before migrating to win 7 now the only thing I can get to work is FF downloader. Internet Download Manager is the best. You can manually set it to detect which browser you are using as some managers only have a predefined set of supported browsers.
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