Added Webhooks methods to complement Stream and E-Mail notifications.

[tinko92]

The commit in this pull request adds the feature to send HTTP(S) requests to a URL that is specified in the admin settings as a notification for new activities, similar to the existing methods of sending notifications about new activities via stream or e-mail. The request contains information about the event in JSON format and optionally a secret string that can be set in the Admin settings and can be verified on the receiving end.

Signed-off-by: Tinko Bartels mail@tinkobartels.de

[MatthiasHertel]

@nickvergessen @icewind1991

hey why not merged ?
i think it would be nice to register more notification provider (slack webhook) for give a possiblity preventing load on mail server.

can u review it and merge ?

it would be nice :)

[nickvergessen]

It might be revisited soon, as there are plans to change activity and notifications in something new

[nickvergessen]

Closing this as in it's current state this is too far from being mergable.

• Curl is used instead of Nextcloud's HTTP client, allowing SSRF
• Webhook results are not signed with a shared secrect, so can not be validated on the recipient side for authenticy, instead the token is send directly as header
• Settings were redone

A follow up approach should be similar to nextcloud/spreed#9458