REST API- Defining proper and intuitive URI - rest

Question

I'm tring to create a little registration app, that will be published as a REST API. It will allow users / systems to create an account on my system. They will pass in a username and a password.
According to the rules that i've read, the "/" in a URI must be used to indicate a hierarchical relationship.
So I'm wondering if this type of a URI follows the rules, and is intuitive enough:
POST http://myregistrations.com/users/user/{user_id},{password}
GET http://myregistrations.com/users/user/{user_id}
PUT http://myregistrations.com/users/user/{user_id},{password}
DELETE http://myregistrations.com/users/user/{user_id}
or should i remove the "users" part from the URI? In that case, if I want to get "all" users, i could just do the following:
GET http://myregistrations.com/user/
DELETE http://myregistrations.com/user/ ** i might not allow this but just for discussion purposes...
And the rest of the methods would look like this:
POST http://myregistrations.com/user/{user_id},{password}
GET http://myregistrations.com/user/{user_id}
PUT http://myregistrations.com/user/{user_id},{password}
DELETE http://myregistrations.com/user/{user_id}
I don't want to over complicate things... but I also want to make sure I follow conventions.
I am leaning towards the second example, where I don't have "users". Given that each part of the URI should map to an addressable resource, and that I won't be allowing batch updates to accounts, having a concept of "users" seems useless at this time. I might be missing something though.
Maybe I'm just splitting hairs. I've been reading other posts here too about defining REST APIs... but I haven't found anything yet.
Thanks.

Answer 1

You can have both concepts (user and users) with a single API. The URI /users/user seems convoluted to me.
Over-simplified example:
Post one user:
POST /user/{user_id,password}
Post multiple users:
POST /user/[{user_id,password},{user_id,password}]
Get one user:
GET /user/{user_id}
Response: {user_name} or [{user_name}]
Get multiple users:
GET /user/{search_user_name}
Response: [{user_name},{user_name},{user_name}]

Answer 2

Typically plural is how you reference a resource so users in this case and not user. This is what you're routes should look like to follow the REST pattern.
POST http://myregistrations.com/users/ --> The post payload should contain: {user_id},{password}
GET http://myregistrations.com/users/{user_id} --> The user_id is in the URL
PUT http://myregistrations.com/users/{user_id} --> The user_id is in the URL
DELETE http://myregistrations.com/users/{user_id} --> The user_id is in the url

Answer 3

I don't want to over complicate things...
I have bad news for you, you've already overcomplicated things. The REST clients know nothing about the URI structure, because they follow hyperlinks annotated with semantic metadata. The clients check this metadata instead of the URI structure.