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Expand shortened URLs

Terminal - Expand shortened URLs
expandurl() { wget -S $1 2>&1 | grep ^Location; }
2011-10-18 18:50:54
User: atoponce
Functions: grep wget
0
Expand shortened URLs

This shell function uses wget(1) to show what site a shortened URL is pointing to, even if there are many nested shortened URLs. This is a great way to test whether or not the shortened URL is sending you to a malicious site, or somewhere nasty that you don't want to visit. The sample output is from:

expandurl http://t.co/LDWqmtDM

Alternatives

There are 3 alternatives - vote for the best!

Terminal - Alternatives
expandurl() { curl -sIL $1 | grep ^Location; }
2011-10-19 00:56:53
User: atoponce
Functions: grep
Tags: curl
5

curl(1) is more portable than wget(1) across Unices, so here is an alternative doing the same thing with greater portability. This shell function uses curl(1) to show what site a shortened URL is pointing to, even if there are many nested shortened URLs. This is a great way to test whether or not the shortened URL is sending you to a malicious site, or somewhere nasty that you don't want to visit. The sample output is from:

expandurl http://t.co/LDWqmtDM
expandurl() { curl -s "http://api.longurl.org/v2/expand?url=${1}&format=php" | awk -F '"' '{print $4}' }
2013-01-19 10:40:46
User: atoponce
Functions: awk
Tags: curl longurl
2

This relies on a public API from http://longurl.org. So, this has the weakness that if the service disappears, the function will break. However, it has the advantage that the shortened URL service will not be tracking your IP address and other metrics, but instead will track longurl.org. Thus, you can remain anonymous from the shortened URL services (although not anonymous from longurl.org). It does no sanity checking that you have provided an argument. If you do not provide one, "message" is displayed to STDOUT.

expandurl() { curl -sIL $1 2>&1 | awk '/^Location/ {print $2}' | tail -n1; }
2011-10-19 01:35:33
Functions: awk tail
Tags: curl
0

This shell function uses curl(1) as it is more portable than wget(1) across Unices, to show what site a shortened URL is pointing to, even if there are many nested shortened URLs. It is a refinement to www.commandlinefu.com/commands/view/9515/expand-shortened-urls to make it better for use in scripts. Only displays final result.

expandurl http://t.co/LDWqmtDM

Know a better way?

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What others think

sweet!

Comment by linuxrawkstar 187 weeks and 2 days ago

Nice, however with bash, you'll need a ; at the end of the grep part.

Comment by flatcap 187 weeks and 2 days ago

Nice, But would like to see a version of this that only prints the last line and/or drops the "Location: " and " [following]" bits.

Comment by defiantredpill 187 weeks and 2 days ago

@flatcap updated. thx. simple missing typo. glad someone is paying attention

@defiantredpill seems simple enough to use by replacing grep(1) with awk(1). submit an alternative!

Comment by atoponce 187 weeks and 2 days ago

@atoponce I forked your curl version instead, just waiting for a mod to look at it as it was my first command.

Comment by defiantredpill 187 weeks and 2 days ago

The wget version not only prints locations, it also downloads.

Comment by wipu 187 weeks and 2 days ago

expandurl() { curl -sIL $1 2>&1 | awk '/^Location/ {print $2}' | tail -n1; }

Comment by defiantredpill 186 weeks and 1 day ago

Your point of view

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