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content/blog/2025-02-15_remove-exif-git-hook.md
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       title = "Removing exif data from images via a pre-commit hook"

     

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       date = 2025-02-15T19:57:01

     

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       slug = "remove-exif-git-hook"

     

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       description = "took longer then it probably should have 😊"

     

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       [taxonomies]

     

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       tags = ["mildrant", "tutorial"]

     

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       [extra]

     

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       has_toc = true

     

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       +++

     

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       I saw this [post](https://jade.fyi/blog/pre-commit-exif-safety/) from [jade.fyi](https://jade.fyi) on using a git hook to clear exif data from your images before you commit them and realized I should probably implement that too lol. Interestingly jade also uses zola for her site but she used pre-commit hooks whereas I wanted to do something that used native git hooks.

     

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       I started with the naive method of just having a `.git/hooks/pre-commit` file that would run `exiftool` on the input but after realizing that hooks placed there wouldn't be synced to the repo decided that wasn't the best way. I moved to using a script that would symlink files from the `hooks` directory to `.git/hooks`. It worked moderately well but due to the fact that I used (yes I feel the shame admitting this [:uw_embarrassed:](https://cachet.dunkirk.sh/emojis/uw_embarrassed/r)) `#!/bin/bash` instead of `#!/usr/bin/env bash`. Not realizing my mistake and believing it to be related to the symlink I found [this stack overflow](https://stackoverflow.com/questions/4592838/symbolic-link-to-a-hook-in-git/#:~:text=While%20you%20can%20use%20symbolic%20links) answer which taught me that you can use `git config core.hooksPath hooks` to move the hooks directory to `./hooks` in the root of your repo! After doing that and it still not working (i feel very dense writing this lol) I finally realized that the shebang was wrong and then it worked!

     

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       {{ img(id="https://cdn.hackclubber.dev/slackcdn/9049d20038cc3058acee1bbe58c5ac3f.png" alt="the commit hook finally working!" caption="phew") }}

     

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       Is there anything at all to learn from this? Well yes actually! You can use the script below and the `git config core.hooksPath hooks` setting to scrub your own images!

     

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       > hooks/pre-commit

     

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       ```bash

     

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       #!/usr/bin/env bash

     

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       # Check if exiftool is installed

     

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       if ! command -v exiftool &> /dev/null; then

     

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         echo "Error: exiftool is not installed.  Please install it." >&2

     

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         exit 1

     

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       fi

     

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       while read -r file; do

     

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         case "$file" in

     

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           *.jpg|*.jpeg|*.png|*.gif|*.tiff|*.bmp)

     

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             echo "Removing EXIF data from: $file" >&2

     

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             exiftool -all= --icc_profile:all -tagsfromfile @ -orientation -overwrite_original "$file"

     

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             if [ $? -ne 0 ]; then

     

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               echo "Error: exiftool failed to process $file" >&2

     

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               exit 1

     

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             fi

     

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             git add "$file"

     

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             ;;

     

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           *)

     

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             ;;

     

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         esac

     

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       done < <(git diff --cached --name-only --diff-filter=ACMR)

     

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       exit -0

     

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       ```

     

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       > if you want to add something or comment on the post then I posted about it on bluesky: [https://bsky.app/profile/dunkirk.sh/post/3liaybkkas226](https://bsky.app/profile/dunkirk.sh/post/3liaybkkas226)