Howdy folks!
I spun up my own Mastodon today and quickly realized there was a 500 character limit to posts. I googled around, found some good guides and decided to make a quick bash script for it. Replace the below values inside the carrots with your settings.
#!/bin/bash -x
docker exec -it mastodon_web sed -i 's/500/<desired_#_of_chars>/g' /opt/mastodon/app/javascript/mastodon/features/compose/components/compose_form.js
docker exec -it mastodon_web sed -i 's/500/<desired_#_of_chars>/g' /opt/mastodon/app/validators/status_length_validator.rb
docker exec -it mastodon_web bundle exec rails assets:precompile
docker container restart <mastodon_web_container> <mastodon_streaming_container> <mastodon_sidekiq_container>
Would a post with over 500 characters show up on an instance that has the 500 character limit?
The 500 character limit is why I rarely use my fosstodon account. Maybe I’ll spin up my own instance. Although I said that about akkoma and I haven’t tried to spin that up.
I don’t mean to discourage you - this is a good hack. But as a seasoned code monkey, I see a few things that can be possibly improved so they will have less chances of biting you in the future. Please feel free to disregard this, of course.
s/500/…/gThis is a bit overbroad, as it replaces any “500” in those files. It works now, as this is probably only occurrence is the limit you want to tweak, but it’s a crude approach that may inadvertently break at any moment.
docker exec
Those changes are ephemeral and won’t survive if container is re-created for any reason (unless
//mastodonis a volume - I guess this is how it survivesdocker container restart?). I would rather recommend building your own custom image. Start by making a patch file:docker run -it --rm -user root <mastodon image> bash cp -r /opt/mastodon /opt/mastodon.vanilla sed <your-updates-here> # or you can run vi or nano or any other editor diff -urN /opt/mastodon.vanilla /opt/mastodon exitTake diff’s output, save it to
fix-limits.patchin a new empty directory, then write a brief Dockerfile next to it, that goes like this:FROM <base-mastodon-image> COPY fix-limits.patch ./ RUN patch -p2 fix-limits.patchAnd finally run
docker build -t my-mastodon .and usemy-mastodonas a replacement image. This will ensure your changes will persist, plus you’ll have a proper patch file that you can use with any version (point is, it will warn you if something would change in a way that the patch would no longer apply cleanly).I’m writing this on a phone, from scratch, without any testing, so you may need to tweak things a little bit. E.g. I’m not sure what’s the WORKDIR in the base image - just assuming its /opt/mastodon (which it probably is), but you may need to edit the COPY command’s second argument and/or
-pparameter to patch.> docker container restartWouldn’t you need to rebuild your image any time the upstream image changes?
Yes - same as with the original script, upgrades would require more manual steps than just updating the version in the Compose file. This is how it’s typically done.
There are ways to automate this. Docker Hub used to have a feature for automatic rebuilds when base images had changed, but AFAIK this feature was removed some years ago. Now it’s a matter of setting up a CI with periodically (nightly or weekly) scheduled pipelines, but it’s not a trivial matter.
Semi-automation can be achieved by using build-time arguments. I’m at my computer now, so here’s a revised process:
First, a bunch of manual commands that would allow us to write a patch. I’ll use those crude
sedstatements - just because they work today, but YMMV.docker run -it --rm --user root tootsuite/mastodon bash cp -r /opt/mastodon /opt/mastodon.vanilla sed -i 's/500/1000/g' /opt/mastodon/app/javascript/mastodon/features/compose/components/compose_form.js sed -i 's/500/1000/g' /opt/mastodon/app/validators/status_length_validator.rb diff -urN /opt/mastodon.vanilla /opt/mastodonThis will produce a nice patch like this that you can copy. Create an empty directory and save as
change-limits.patchin there:diff -urN /opt/mastodon.vanilla/app/javascript/mastodon/features/compose/components/compose_form.js /opt/mastodon/app/javascript/mastodon/features/compose/components/compose_form.js --- /opt/mastodon.vanilla/app/javascript/mastodon/features/compose/components/compose_form.js 2023-07-07 17:50:26.046682458 +0000 +++ /opt/mastodon/app/javascript/mastodon/features/compose/components/compose_form.js 2023-07-07 17:50:49.626674917 +0000 @@ -90,7 +90,7 @@ const fulltext = this.getFulltextForCharacterCounting(); const isOnlyWhitespace = fulltext.length !== 0 && fulltext.trim().length === 0; - return !(isSubmitting || isUploading || isChangingUpload || length(fulltext) > 500 || (isOnlyWhitespace && !anyMedia)); + return !(isSubmitting || isUploading || isChangingUpload || length(fulltext) > 1000 || (isOnlyWhitespace && !anyMedia)); }; handleSubmit = (e) => { @@ -280,7 +280,7 @@ </div> <div className='character-counter__wrapper'> - <CharacterCounter max={500} text={this.getFulltextForCharacterCounting()} /> + <CharacterCounter max={1000} text={this.getFulltextForCharacterCounting()} /> </div> </div> diff -urN /opt/mastodon.vanilla/app/validators/status_length_validator.rb /opt/mastodon/app/validators/status_length_validator.rb --- /opt/mastodon.vanilla/app/validators/status_length_validator.rb 2023-07-07 17:50:26.106682438 +0000 +++ /opt/mastodon/app/validators/status_length_validator.rb 2023-07-07 17:51:00.796671166 +0000 @@ -1,7 +1,7 @@ # frozen_string_literal: true class StatusLengthValidator < ActiveModel::Validator - MAX_CHARS = 500 + MAX_CHARS = 1000 URL_PLACEHOLDER_CHARS = 23 URL_PLACEHOLDER = 'x' * 23Now, put the Dockerfile next to the patch:
ARG MASTODON_VERSION=latest FROM tootsuite/mastodon:${MASTODON_VERSION} USER root RUN apt-get update && apt-get install -y --no-install-recommends patch COPY change-limits.patch ./ RUN patch -up3 < change-limits.patch USER mastodon RUN OTP_SECRET=precompile_placeholder SECRET_KEY_BASE=precompile_placeholder rails assets:precompileAnd a shell script to semi-automate the upgrades. Note it requires
curlandjqto be available to parse JSON.#!/bin/sh set -e MASTODON_VERSION="$(curl -s "https://hub.docker.com/v2/namespaces/tootsuite/repositories/mastodon/tags?page_size=100" | jq -r '.results[]["name"]' | sort -rV | head -n 1)" echo "Latest version: ${MASTODON_VERSION}" docker pull "tootsuite/mastodon:${MASTODON_VERSION}" docker build --build-arg "MASTODON_VERSION=${MASTODON_VERSION}" -t "my-mastodon:${MASTODON_VERSION}" .And finally, create a file called
.dockerignorethat contains only one line that would saybuild.sh. That’s just minor cosmetic touch saying that ourbuild.shis not meant to be a part of the build context. If everything is correct, there should be now 4 files in the directory:.dockerignore,build.sh,change-limits.patchandDockerfile.Now when you run
build.shit will automatically find the latest version and build you a custom image tagged as e.g.my-mastodon:v4.1.3, which you can use in your Compose file. For a distributed system like Docker Swarm, Nomad or Kubernetes you’ll want to tweak this script a little to use some registry (your-registry.example.org/your/mastodon:v4.1.3) and possibly even apply changes further (e.g.docker service update --image ...).Mutable tags like
latestcan become confusing or even problematic (e.g. if you’ll want to downgrade it’s best to have previous version image readily available for some time - even if the build process is reproducible), so I would really recommend to use explicit version number tags.Hope this helps.
Oh I know my workaround is probably the worst possible correct answer for how to do this. Thanks for that, I’ll give it a shot!
It’s OK. I do hacks like this all the time - no shame in this. However, when sharing a recipe with others it’s best to promote better practices :)
