# PATCH expects id redundantly in URL and as a parameter

**URL:** <https://discuss.jsonapi.org/t/patch-expects-id-redundantly-in-url-and-as-a-parameter/571>\
**Category:** Uncategorized\
**Created:** [June 22, 2016, 2:39pm UTC](https://discuss.jsonapi.org/t/patch-expects-id-redundantly-in-url-and-as-a-parameter/571 "2016-06-22T14:39:26Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![andreas](https://sea2.discourse-cdn.com/flex016/user_avatar/discuss.jsonapi.org/andreas/32/294_2.png) [@andreas](https://discuss.jsonapi.org/u/andreas)\
**Post date:** [June 22, 2016, 2:39pm UTC](https://discuss.jsonapi.org/t/patch-expects-id-redundantly-in-url-and-as-a-parameter/571/1 "2016-06-22T14:39:26Z")

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I try to implement a REST API following the json:api spec, but I am a bit confused.

In the “Updating Resources” section, the spec (v1.0) states that the …

> resource can be updated by sending a PATCH request to the URL that represents the resource.

and

> The PATCH request MUST include a single resource object as primary data. The resource object MUST contain type and id members.

A REST API would define `PATCH /{resource}/{id}`, just like it was done in the example in that section.

That begs the question why the id has to be provided as a parameter, when it is already available per URL. What if the IDs in the URL and in the parameter differ? Surely they must (as in MUST) always be equal?

I suppose non-REST APIs shall be possible, to, but as far as I can see, I would much prefer if ID could be optional.

Many thanks for the feedback!

Update: The DELETE call, on the other hand, seems to be fine without any further parameters, just `DELETE /{resource}/{id}`

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**Author:** ![jlangley](https://avatars.discourse-cdn.com/v4/letter/j/9e8a1a/32.png) [@jlangley](https://discuss.jsonapi.org/u/jlangley)\
**Post date:** [June 23, 2016, 10:03pm UTC](https://discuss.jsonapi.org/t/patch-expects-id-redundantly-in-url-and-as-a-parameter/571/2 "2016-06-23T22:03:07Z")

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> [@andreas](#):
>
> Surely they must (as in MUST) always be equal?

Why?  
I can’t see a good reason for making them different if they _could_ be the same (indeed JSON API recommends this), **but** there’s no reason why a JSON API _has_ to use this URL format, or even has to have **only** a single URL that refers to a resource.

Consider the example on the website:  
`http://example.com/articles/1/author` and `http://example.com/people/9` both refer to the same resource (at least at one particular time), and a client could issue a PATCH request to either URL to modify the author resource.

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**Author:** ![andreas](https://sea2.discourse-cdn.com/flex016/user_avatar/discuss.jsonapi.org/andreas/32/294_2.png) [@andreas](https://discuss.jsonapi.org/u/andreas)\
**Post date:** [June 24, 2016, 8:35am UTC](https://discuss.jsonapi.org/t/patch-expects-id-redundantly-in-url-and-as-a-parameter/571/3 "2016-06-24T08:35:06Z")

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Indeed, thank you! I suspected I must have missed something obvious, and the example you gave clarifies it.