Dedicated admin API to create new users (and not update existing users)

[damnms]

Description:

i have a little application which can create new users on homeservers. it talks to the homeserver through the admin rest api and therefore requires a valid admin user.
now i noticed that those PUT requests are not only creating but also updating existing users.

https://restfulapi.net/rest-put-vs-post/

POST /device-management/devices : Create a new device

At the moment, only the second part is supported by matrix synapse:

PUT /device-management/devices/{id} : Update the device information identified by "id"

https://github.com/matrix-org/synapse/blob/master/docs/admin_api/user_admin_api.rst#create-or-modify-account

So i have to check if the user already exists and then create it. Its just a small thing but i would really appreciate it, if there is some kind of:

POST /_synapse/admin/v2/users/

with a body like:

{user: "someNewUser", password: "someNewPassword"}

which returns an Error when the user which should be created already exists.

I guess that is very common in the web that an exception is thrown when a user already exists instead of (accidentally) updating the password... thats what happened to my little project. Lucky me it is only in testing yet :)

[babolivier]

This could also be done in a simpler way by adding an update property to the existing API (that would default to true) that updates the user if it already exists if true, and returns an error in this case if false.

Given our current load and priorities this isn't something we'll likely pick up soon, however if you (or anyone else stumbling upon this issue) want to take it on, we'd gladly welcome a PR 🙂

[awesome-manuel]

POST normally let's the server generate the object ID (user ID in our case), but unless you create a guest account, you would want to set the user ID yourself.