Recursively changing the content-type for files of a given extension on Amazon S3

Solution 1:

Here is an example how to do this with the aws cli tool. The cp tool allows the use of a recursive options, which I don't think the s3api tool can do. In this case, I'm fixing a bunch of SVGs. Remove the --dryrun options when you are ready to unleash it.

aws s3 cp \
      --exclude "*" \
      --include "*.svg" \
      --content-type="image/svg+xml"  \
      --metadata-directive="REPLACE" \
      --recursive \
      --dryrun \
       s3://mybucket/static/ \
       s3://mybucket/static/

Solution 2:

Unless you want to get your hands dirty using boto/python or another AWS API, I suspect your best bet would be to use $ aws s3api copy-object with the --content-type flag to copy an object to itself, setting the new content type.

Here's the documentation for s3api.

It goes without saying that you should test this first, before running it recursively on your whole bucket.

---

Solution 3:

After some digging, I found that the s3cmd tool can do this. For example, to set JSON files to application/json:

s3cmd --recursive modify --acl-public \
       --add-header='content-type':'application/json' \
       --exclude '' --include '.json' \
       s3://bucket/

---

Solution 4:

As mentioned earlier, you can use aws tool by Amazon and use s3api to copy-object onto itself, and use metadata-directive=REPLACE to change the content-type.

I am putting this here, because sometimes you would want to iterate on filenames that are stored in database, and this is how you can do it through cli.

aws s3api copy-object \
          --content-type="application/vnd.android.package-archive" \
          --metadata-directive="REPLACE" \
          --copy-source "MYBUCKET/FILE.apk" \
          --bucket "MYBUCKET" \
          --key "FILE.apk" \
          --acl public-read