SED - Prefix all jpg files with full URL

Question

I have an HTML file with local paths to images like so - /image1.jpg or /image2.png

I want to use SED to prefix a desired url to that like so - https://example.com.

Desired result is https://example.com/image1.jpg

I tried this -

sed "s#.*.jpg#https://example.com/*.jpg#g" index.html > index2.html

The result is index2.html which finds the image names but my replacement does not use those names. How to keep that match name?

Any suggestions?

Sample Input -

<img src="Image1.jpg" alt="boat" /><figcaption>boat</figcaption>

Sample Output -

<img src="https://example.com/image1.jpg" alt="boat" /><figcaption>boat</figcaption>

Answer 1

You can use

sed 's~\(="\)\([^"]*\.jpg"\)~\1https://example.com/\2~g'

Details:

• \(="\) - Group 1 (\1): =" string
• \([^"]*\.jpg"\) - Group 2 (\2): any zero or more chars other than " and then .jpg" substring.

See the online demo:

#!/bin/bash
s='<img src="Image1.jpg" alt="boat" /><figcaption>boat</figcaption>'
sed 's~\(="\)\([^"]*\.jpg"\)~\1https://example.com/\2~g' <<< "$s"

Output:

<img src="https://example.com/Image1.jpg" alt="boat" /><figcaption>boat</figcaption>

Answer 2

This is what finally worked easily. Thanks for everyone's input. Trying to get it to work in a batch file on Windows was painful.

Command line -

sed -f sedscript.sed index.html > index2.html

Content of sedscript.sed

s#src="#&https://example.com/#g