Problem :
Usually one would download a file with a URL ending in the file extension.
To download Ubuntu ISO, one would simple
wget http://releases.ubuntu.com/14.04.3/ubuntu-14.04.3-desktop-amd64.iso
However, I came accross a site that I suspect uses ASP.Net / IIS.
A link to a ISO is in this form (I removed link contents incase of … policies):
http://some.ip.in.here/website.com/IMAGENAME.ISO?md5=hUhpyFjk7zEskw06ZhrWAQ&expires=1454811899
I am not sure how to download this since it has the MD5 and expiry time as parameters, and so wget only downloads a web page, not this ISO.
Any suggestions?
Solution :
Use
wget "http://some.ip.in.here/website.com/IMAGENAME.ISO?md5=hUhpyFjk7zEskw06ZhrWAQ&expires=1454811899"
Explanation:
There is “&” character in the url. On linux and alike systems, this makes it a background process. Solution it to enclose url in double quoutes (“) so that its treated as one argument.
If you are just trying to get a reasonable filename the complex URL, you can use the output-document option.
-O file
--output-document=file
Either of these forms will work.
As noted previously, be sure none of the special characters in the URL are getting interpreted by the command parser.
There are two ways you can do this using Curl.
In this first method you would the -O flag to write out the file based on the remote name from the URL; in this case it would most likely write the file out to the system as IMAGENAME.ISO?md5=hUhpyFjk7zEskw06ZhrWAQ&expires=1454811899; note how the URL value is contained by double quotes since & and ? might be misinterpreted as Bash commands:
curl -O -L "http://some.ip.in.here/website.com/IMAGENAME.ISO?md5=hUhpyFjk7zEskw06ZhrWAQ&expires=1454811899";
While that method technically “works” but the filename is confusing at best. So in this other method you would use output redirection—with > followed by a filename after the URL—to output the file contents to a file named IMAGENAME.ISO:
curl -L "http://some.ip.in.here/website.com/IMAGENAME.ISO?md5=hUhpyFjk7zEskw06ZhrWAQ&expires=1454811899" > "IMAGENAME.ISO";
So if you ask me, the second method works best for most average use. Also notice the -L flag being used in both commands; that commands tells Curl to follow any redirection links that a file download URL might have since a lot of times files on download services redirect a few times before landing at the destination payload file.