How to use apps/transport/lib/transport/gtfs_diff.ex?

[dancesWithCycles]

Hi folks,
Thank you so much for providing and maintaining this repository.

I randomly stumbled over this readme file that leaded me to this source file.

It is the first time I come across Elixir. Do you mind providing an instruction set that describes how to use the GTFS Diff tool from scratch imagining a clear Linux operating system environment?

Example:

• prepare Elixir

cd
apt install curl git
git clone https://github.com/asdf-vm/asdf.git ~/.asdf --branch v0.14.0

orThis issue is linked to [this issue](https://github.com/etalab/transport-site/issues/3981).



git clone https://aur.archlinux.org/asdf-vm.git && cd asdf-vm && makepkg -si

Add the following to ~/.bashrc:

. "$HOME/.asdf/asdf.sh"

Completions must be configured by adding the following to your .bashrc:

. "$HOME/.asdf/completions/asdf.bash"

• install plugins

asdf plugin-add erlang (https://github.com/asdf-vm/asdf-erlang)
asdf plugin-add elixir

• get repo

cd
git clone [email protected]:etalab/transport-site.git
cd transport-site

• run Elixir tool

mix cmd --app  apps/transport/lib/transport/gtfs_diff.ex

This issue is linked to this issue.

Cheers!

[thbar]

Hi @dancesWithCycles! Thanks for the issue 😄

It is the first time I come across Elixir. Do you mind providing an instruction set that describes how to use the GTFS Diff tool from scratch imagining a clear Linux operating system environment?

I would need to verify my understanding: are you asking for help on the tool, or you do not need help and instead are suggesting an improvement on the documentation?

Thanks!

[dancesWithCycles]

Hi @thbar ,
Thx for asking for clarification. Indeed, I am asking for both. An extension to the documentation with the instruction set to install the dependencies and use the tool in a clean Linux (e.g. GNU/Debian) environment would help me to run the GTFS Diff tool. But it also would help others that miss a running Elixir environment on hand. Of course, a more complete documentation would help everyone.

Cheers!

[thbar]

Thanks for the clarification @dancesWithCycles!

After a long day, coming back with some points: one must note that the current implementation of GTFS-Diff does not scale well (this is why there is a 10MB limit on https://transport.data.gouv.fr/tools/gtfs_diff).

This means we are not going to put a lot of effort in the documentation (it will likely change if we optimise the algorithm later).

I will see if I can tweak things in a few lines to make things work from a script, and provide guidance here (because mix cmd --app apps/transport/lib/transport/gtfs_diff.ex will not work currently unless I'm mistaken).

I'll keep that issue opened for now, thanks for your patience.

[thbar]

@dancesWithCycles thanks for the delay. Our bandwidth is too tight to properly manage that, so I will have to close the issue for now. Sorry about that, as we manage a lot of topics!