add baseUrl parameter to support slack-compatible integrations

[Reamer]

• Remove Merge Conflicts from add baseUrl parameter to support slack-compatible integrations #204
• Add some documentation

[samrocketman]

@Reamer can you amend your PR so that there's two commits? One commit for the author of #204 and a second commit for your additional changes? I prefer to preserve credit where due in the contributor statistics.

Actually, since you resolved conflicts that may no longer be easily done. Tell me your thoughts.

[samrocketman]

I'll test this change now.

[samrocketman]

So far in my testing; upgrading the plugin from 2.1 to 2.2-SNAPSHOT doesn't break any configurations. That's a good start. Now I'm going to review the code.

[samrocketman]

I have mattermost configured on http://localhost:8065/. How do I configure the Slack plugin to interact with it? I don't know how to test this feature.

Bootstrap Jenkins with slack configured and a mattermost machine (requires vagrant).

1. Clone https://github.com/samrocketman/jenkins-bootstrap-slack
2. Bring up mattermost; vagrant up; once mattermost is up you can visit http://localhost:8065/.
3. Bring up Jenkins; ./slack_bootstrap.sh; The end of the console output will include how to log into it.

Beyond that; I don't know how to test the integration.

[Reamer]

@samrocketman You have now write access to my branch.
To test this feature with mattermost:

1. Login to Mattermost
2. click in the upper right corner on three points
3. click on Integrations
4. click on Incoming Webhooks
5. Create a Webhook
6. You should now have a URL with a Token, something like this (https://mydomain.com/hooks/xxxxxxxxxxxxxx)
7. "https://mydomain.com/hooks/" is your baseUrl + "xxxxxxxxxxxxxx" your token.

Now I will take a look into your Vagrant-Box

[Reamer]

@samrocketman: Vagrant is up and running, but I doesn't want a local jenkins server on my os. I was wondering that the integration button was missing. After a clean install you must enable this integration
Go to http://localhost:8065/admin_console/integrations/custom and enable webhook integration. After this you can follow my instructions in my last comment.

Let me know ,if I can help you with testing.

[samrocketman]

Thanks, I'll try it tomorrow.

[samrocketman]

What works

Upgrading plugin preserves settings for existing slack configurations.

All plugin settings were preserved when I updated the Base URL. Notifying mattermost was also successful. Here's a screenshot of some output.

What doesn't work

Test Connection

So far adding a trailing slash is required. I configured Base URL = http://localhost:8065/hooks/ and "Test Connection" button succeeded. However, Base URL = http://localhost:8065/hooks causes "Test Connection" button to fail. It should not matter; this is a bug.

[samrocketman]

Fully Tested

Okay, this has FINALLY been successfully tested. I tested the following:

1. Upgrading configurations from prior version of Slack plugin (success).
2. Configured with Mattermost using http://localhost:8065/hooks (no trailing slash) (success).
3. Configured with Mattermost using http://localhost:8065/hooks/ (trailing slash) (success).

This pull request is ready to be merged!

[samrocketman]

Thanks for your work @Reamer and @andrzejwp.

[samrocketman]

Feel free to subscribe to #296 for updates related to Slack Plugin 2.2 release.

[andrzejwp]

Great! Sorry I didn't asist further. Hope this makes it to the public release soon. Thanks!

[samrocketman]

No worries. It's challenging to stay on top of volunteer stuff so I appreciate your contributions.