Sviluppo di plugin per Discourse - Parte 4 - Configurare git

[Discourse]

Tutorial precedente: Developing Discourse Plugins - Part 3 - Add custom site settings

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Ora che il tuo plugin sta diventando più sofisticato, è il momento di adottare un approccio più raffinato per lo sviluppo.

Ti suggeriamo di utilizzare git come sistema di controllo versione per il tuo plugin. Ti raccomandiamo anche di usare github per condividere il codice del tuo plugin con altri.

Creazione del repository Git

Una volta creato il tuo account GitHub, visita questo URL per creare un nuovo repository. Puoi chiamarlo come preferisci, ma in genere è buona norma iniziare con discourse-. Assicurati che il repository sia pubblico. Ecco com’era il mio schermo:

Creazione della cartella di lavoro locale

A questo punto creo una directory locale sul mio computer per contenere il plugin. Di solito la metto in ~/code, ma puoi metterla ovunque tu voglia sul tuo computer:

mkdir -p ~/code/discourse-plugin-test
cd ~/code/discourse-plugin-test

Ora seguiamo le istruzioni di GitHub per inizializzare il repository con un README:

echo "# discourse-plugin-test" >> README.md
git init
git add README.md
git commit -m "primo commit"
git remote add origin git@github.com:eviltrout/discourse-plugin-test.git
git push -u origin main

Infine, crea un file plugin.rb per il tuo plugin come spiegato nella parte 1. Per questo esempio ho creato semplicemente un file fittizio:

plugin.rb

# name: discourse-plugin-test
# about: Mostra come configurare Git
# version: 0.0.1
# authors: Robin Ward

Creazione di un symlink

Poiché hai seguito la nostra guida per sviluppatori, dovresti avere una copia di Discourse clonata da qualche parte sul tuo computer. Ho clonato la mia in ~/code/discourse, ma ancora una volta potresti averla messa ovunque e questo dovrebbe funzionare ugualmente se aggiusti di conseguenza il codice seguente:

cd ~/code/discourse/plugins
ln -s ~/code/discourse-plugin-test .

Il codice sopra ha creato un link simbolico tra il codice di Discourse e la cartella del tuo plugin. Riavvia il server di sviluppo e dovresti vedere che il tuo plugin funziona!

La bellezza di questa configurazione è che puoi semplicemente inviare il tuo plugin su GitHub senza preoccuparti della codebase di Discourse in cui risiede. Le tue modifiche saranno isolate al plugin stesso. Se hai bisogno di modificare il codice di Discourse, puoi farlo comunque, ma Git traccierà le modifiche separatamente!

Ti consiglio di usare una finestra dell’editor per la codebase del tuo plugin e un’altra per Discourse stesso. È più facile quando li consideri due cose diverse.

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Altri articoli della serie

Parte 1: Nozioni di base sui plugin
Parte 2: Outlet dei plugin
Parte 3: Impostazioni del sito
Parte 4: Questo argomento
Parte 5: Interfacce di amministrazione
Parte 6: Test di accettazione
Parte 7: Pubblica il tuo plugin

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Questo documento è sotto controllo versione - suggerisci modifiche su GitHub.

[AhmadF.Cheema]

• After many frustrating attempts, found out that apparently ln -s does not work in a Windows environment, or atleast not how it should.
• ln -s essentially just copy-pasted the plugin folder into the discourse/plugins folder
• Apparently, in Windows the way to create symbolic links is to use the mklink command in command prompt (run as administrator, and this command does not natively run in Windows PowerShell either).
• Using the mklink command (with both arguments /d and /h), although the created symbolic link could be seen present in the directory, the plugin was not working with discourse (and also not showing in /admin/plugins).
• I tried this multiple times with restarting the rails server, deleting the tmp folder, but to no avail.

@eviltrout, any idea what could I be doing wrong?

[eviltrout (Robin Ward)]

I assume you are using Vagrant on windows? If you can’t get the symbolic links sent over, I think the only way you can do it is to copy the plugin into discourse/plugins manually and work from there. It should work as long as you are not making changes to the core discourse app at the same time, which confuses git.

When your plugin is ready, you’ll want to copy it to another directory to package it up for git.

[AhmadF.Cheema]

Yeah, OK this should be fine too.
Although the OCD side of me, much preferred the comparatively “cleaner” symbolic links method.

Anyway, Thanks.

[pacharanero (Marcus Baw)]

@AhmadF.Cheema I had similar problems with the symlinking using Vagrant 1.9.8 on Linux, and a completely standard Discourse Vagrant development environment as per the docs.

The problem is simple when you look into it. From the scope of inside the Vagrant VM, the destination of the symlink is not a valid path. Try executing the command ls -al in the plugins directory inside your VM (in a standard install this is at /vagrant/plugins)

vagrant@discourse:/vagrant/plugins$ ls -al
total 36
drwxr-xr-x 1 vagrant vagrant 4096 Oct 22 09:08 ./
drwxr-xr-x 1 vagrant vagrant 4096 Oct 22 09:10 ../
drwxr-xr-x 1 vagrant vagrant 4096 Sep  7 19:51 discourse-details/
drwxrwxr-x 1 vagrant vagrant 4096 Oct 21 13:56 discourse-narrative-bot/
drwxr-xr-x 1 vagrant vagrant 4096 Oct 21 13:56 discourse-nginx-performance-report/
drwxr-xr-x 1 vagrant vagrant 4096 Sep  7 19:51 discourse-plugin-outlet-locations/
drwxrwxr-x 1 vagrant vagrant 4096 Oct 21 13:56 discourse-presence/
lrwxrwxrwx 1 vagrant vagrant   55 Oct 22 09:08 my-basic-plugin -> /home/marcus/code/discourse/my-basic-plugin
drwxr-xr-x 1 vagrant vagrant 4096 Oct 21 13:56 lazyYT/
drwxr-xr-x 1 vagrant vagrant 4096 Oct 21 13:56 poll/

As you can see, the path /home/marcus/code/discourse/my-basic-plugin cannot possibly be accessible from the VM because it doesn’t exist inside the VM!

The solution is to delete the externally created symlink and set up a separate shared folder in Vagrant, by adding a line to your Vagrantfile:

config.vm.synced_folder "/home/marcus/code/my-basic-plugin",  "/my-basic-plugin"

Then restart the Vagrant VM: vagrant halt && vagrant up so that this change is picked up

Now, when you enter your VM via SSH using vagrant ssh you can create a symlink inside the VM:

cd /vagrant/plugins
ln -s /my-basic-plugin .

Now you can develop in a neatly isolated local folder, and have the neat Git workflow that @eviltrout describes, and the symlinking happens inside the VM. Note that outside the VM, the symlink will be broken - but this shouldn’t matter for our purposes.

[sam (Sam Saffron)]

If you are developing on Linux using our docker based dev is way simpler

[schungx (Stephen Chung)]

Windows symlinks are different from Unix symlinks, thus your confusion. Windows synlinks are very fussy, requiring particular versions of OS to support and sometimes applications must be written to be aware of this. In other words, the stars must line up perfectly for windows symlinks to work.

A hard link (/H) I dont think work with directories. Your /D makes a symlink on a directory, trumping your /H (which is used to create a hard link to a file, not a directory).

Confusing? Welcome to Windows.

There are four types of links in Windows:

• MKLINK (no flags) – symbolic link to file
• MKLINK /H – hard link to file
• MKLINK /D – symbolic link to directory
• MKLINK /J – junction (i.e. hard link) to directory

What you need is is a junction which is Windows-speak for hard link to a directory.

Do MKLINK /J to your plugins directory and the system will treat it as a subdirectory. In fact it won’t know otherwise. Beware, it is not common to have a Windows directory (folder in Windows-speak) to point to the same place as another directory, so you’ll get confused very easy and forget that both are the same things.

That’s why you’ll need to run the command in Administrator mode, otherwise Windows won’t let you create the directory junction.

[pacharanero (Marcus Baw)]

Thanks for the info regarding Windows symlinks @schungx - it should be of help to the OP.

The workaround I described should work fine on any platform, since the symlinks happen inside the (Ubuntu) vagrant box

M

[schungx (Stephen Chung)]

Yup, you’re right. If you can avoid it, avoid messing with Windows. Windows is very picky and may choose to die or go wrong at the most unfortunate moment…

[1c7 (Cheng Zheng)]

Work for me! 2018-4-29

1. I put discourse & my plugin in Desktop

instead of put 1c7-plugin under discourse/plugin

2. and put a “alias” into discourse/plugins folder

alias is a macOS concept,
it’s the same things as ln -s command

3. Discourse correctly load the plugin

(After reboot server with rails s)

4. Now they are separated, use git to manage code is much easier

Thanks!

[maaatt]

Impossibile far funzionare il symlink nella configurazione Docker di macOS. I plugin funzionano solo se copiati direttamente nella cartella dei plugin.