I might be blind and just not seeing it in the documentation, but is there a parameter that I can pass in that will return all the fields available in an endpoint instead of having to list out all of the fields?
I looked for the same thing when I started working with the API and I don't believe it exists (if it does it's not documented). Whatever fields you explicitly call for are the ones that you get back (if you call for none you get ID and ETAG only).
Whatever solution you come up with for your application, one thing to keep in mind is that if you include a field in the call which doesn't exist on the model, e.g. ask for a field called document on a matter, the entire call will return nothing. So, you can't, for instance, just request all the fields from the entire API, which would be convenient, but you could build up a list of all the fields which occur on a particular subsection. I ended up doing something like that for subfields (which are also not returned unless specifically asked for, which is annoying).
All you need to do is ?fields= at the end for return all fields
?fields= returns all with no value needed for a wild card
?fields= returns all with no value needed for a wild card
Related
I'm rewriting an API to be more RESTful, but I'm struggling with a design issue. I'll explain the situation first and then my question.
SITUATION:
I have two sets resources users and items. Each user has a list of item, so the resource path would like something like this:
api/v1/users/{userId}/items
Also each user has an isPrimary property, but only one user can be primary at a time. This means that if I want to get the primary user you'd do something like this:
api/v1/users?isPrimary=true
This should return a single "primary" user.
I have client of my API that wants to get the items of the primary user, but can't make two API calls (one to get the primary user and the second to get the items of the user, using the userId). Instead the client would like to make a single API call.
QUESTION:
How should I got about designing an API that fetches the items of a single user in only one API call when all the client has is the isPrimary query parameter for the user?
MY THOUGHTS:
I think I have a some options:
Option 1) api/v1/users?isPrimary=true will return the list of items along with the user data.
I don't like this one, because I have other API clients that call api/v1/users or api/v1/users?isPrimary=true to only get and parse through user data NOT item data. A user can have thousands of items, so returning those items every time would be taxing on both the client and the service.
Option 2) api/v1/users/items?isPrimary=true
I also don't like this because it's ugly and not really RESTful since there is not {userId} in the path and isPrimary isn't a property of items.
Option 3) api/v1/users?isPrimary=true&isShowingItems=true
This is like the first one, but I use another query parameter to flag whether or not to show the items belonging to the user in the response. The problem is that the query parameter is misleading because there is no isShowingItems property associated with a user.
Any help that you all could provide will be greatly appreciated. Thanks in advance.
There's no real standard solution for this, and all of your solutions are in my mind valid. So my answer will be a bit subjective.
Have you looked at HAL for your API format? HAL has a standard way to embed data from one resources into another (using _embedded) and it sounds like a pretty valid use-case for this.
The server can decide whether to embed the items based on a number of criteria, but one cheap solution might be to just add a query parameter like ?embed=items
Even if you don't use HAL, conceptually you could still copy this behavior similarly. Or maybe you only use _embedded. At least it's re-using an existing idea over building something new.
Aside from that practical solution, there is nothing in un-RESTful about exposing data at multiple endpoints. So if you created a resource like:
/v1/primary-user-with-items
Then this might be ugly and inconsistent with the rest of your API, but not inherently
'not RESTful' (sorry for the double negative).
You could include a List<User.Fieldset> parameter called fieldsets, and then include things if they are specified in fieldsets. This has the benefit that you can reuse the pattern by adding fieldsets onto any object in your API that has fields you might wish to include.
api/v1/users?isPrimary=true&fieldsets=items
I'm looking for some guidance/advice/input on the concept of filtering resources when making a REST API call. Let's say I have Users and Posts, and a User creates a Post. If I want to get all Posts, I might have a route as follows:
GET /api/posts
Now if I wanted to get all posts that were created after a certain date, I might add a filter parameter like so
GET /api/posts?created_after=2017-09-01
However, let's say I want to get all posts by Users that were created after a certain date. Is this the right format?
GET /api/posts?user.created_after=2017-09-01
When it comes to filtering, grouping, etc, I'm having a hard time figuring out the right stuff to do for REST APIs, particularly when using a paginated API. If I do this client side (which was my initial thought) then you potentially end up with a variable number of resources per page, based on what meets your criteria. It seems complicated to add all of this logic as query parameters over the API, but I can't see any other way to do it. Is there a standard for this kind of thing?
There is no objective 'right' way. If using user.created_after logically makes sense in the context of your API, then there's nothing really wrong with it.
Personally, I would not use user.created_after.
I would rather prefer one of the following options:
Option I: /api/posts/users/{userid}?created_after=2017-09-01
Option II: /api/posts/?user={userid}&created_after=2017-09-01
The reason is simple: It looks wrong to me to create dynamic query parameters. Instead you can combine the query parameters (Option II) or even define a more specific resource (Option I).
Regarding pagination: the standard approach is something like this: In addition to filter parameters, you define the following parameters: page and pageSize. When constructing the request, client will specify something like page=2&pageSize=25&orderBy=creationDate.
It's important to note that server must always validate the parameters and can potentially ignore or override incorrect parameters (e.g. page doesn't exist, or pageSize is too big may not return an error, but instead returning reasonable output. This really depends on your business case)
Suppose there's USERS and ORDERS
for a specific user's order list
You could do
/user/3/order_list
/order/?user=3
Which one is prefered and why?
Optional parameters tend to be easier to put in the query string.
If you want to return a 404 error when the parameter value does not correspond to an existing resource then I would tend towards a path segment parameter. e.g. /customer/232 where 232 is not a valid customer id.
If however you want to return an empty list then when the parameter is not found then query string parameters. e.g. /contacts?name=dave
If a parameter affects an entire URI structure then use a path e.g. a language parameter /en/document/foo.txt versus /document/foo.txt?language=en
If unique identifiers to be in a path rather than a query parameter.
Path is friendly for search engine/browser history/ Navigation.
When I started to create an API, I was thinking about the same question.
Video from apigee. help me a lot.
In a nutshell when you decide to build an API, you should decide which entity is independent and which is only related to someone.
For example, if you have a specific endpoint for orders with create/update/delete operations, then it will be fine to use a second approach /order/?user=3.
In the other way, if orders have only one representation, depends on a user and they don't have any special interaction then you could first approach.
There is also nice article about best practice
The whole point of REST is resources. You should try and map them as closely as possible to the actual requests you're going to get. I'd definitely not call it order_list because that looks like an action (you're "listing" the orders, while GET should be enough to tell you that you're getting something)
So, first of all I think you should have /users instead of /user, Then consider it as a tree structure:
A seller (for lack of a better name) can have multiple users
A user can have multiple orders
An order can have multiple items
So, I'd go for something like:
The seller can see its users with yourdomain.com/my/users
The details of a single user can be seen with yourdomain.com/my/users/3
The orders of a single user can be seen with yourdomain.com/my/users/3/orders
The items of a single order can be seen with yourdomain.com/my/users/3/orders/5
Lets say client does GET request for /items/color/{color}
When server returns array of objects that have said color, should each item object have color property or not?
Client knows the color of returned items because he requested that color, so should server try to make a response size smaller or no?
EDIT: Can people touch more on saving bandwidth part? If it's better to return whole resource, can the answers include why it's better to return whole resource versus saving bandwidth, instead of just why whole resource should be returned.
In general (at least that's the idea of REST as I understand it), the result for the request should always be the complete resource. If the item contains a member color, there's no reason to suppress that member in the result. That would contradict the concept of resources of REST. A resource doesn't change its properties.
Suppressing members would not only come unexpected, it might even break the client when it actually expects that member.
Lets assume the client has functionality to parse the result of your REST call without a filter. All fields would be returned and the client would parse all the fields. Now the client requests the exact same resources (item), but suddenly the fields are different - the code from above to parse the result can not be reused.
Also, when you think about it, it's probably more work to suppress that member than to just return it.
There is no "correct" answer, this depends on general API design and should be your decision.
I would agree with Thorstens comment that you should return the whole resource - this is close to the general REST idea. While you do that, you can also implement some mechanism of choosing fields like in FB API: see "Choosing fields" section of this paragraph.
You should keep the color in the response. There would be multiple reasons for this:
You make sure that what you requested for is what you get
If there are multiple items of different colors in the page, you don't let the client take care of "filtering" the items based on colors
You have a more "secure" response. For example, the client requests for blue color , but then a malicious script would manipulate this response as red items.
I'm designing a RESTful API and I'm asking myself question about the filter field.
On my gets queries I want the user to be able to select the fields he want to get in the response. I was pretty sure that it would be the field filter jobs to give me the requested field but, after some reshearch, I found that most of the time it's used to add criteria on the fields, as a IF. Is it the user that needs to make show or hide the fields ans the Api return the full ressource everytime ?
I got an other question which is about the URI representation of such filter. Should it be something like /foo?fields=[bar1,bar2] ?
Thanks
It's not common to have a resource where you can specify what fields you want returned, by default all fields will get returned. If your resource has a lot of fields or some fields have really big values, it can be a good idea to have a way to specify which fields you want returned.
In REST there are no strict rules about how you should design your URLs for filters. It is indeed common to use GET parameters because they can be optional and don't have to be in any specific order. Your proposal of /foo?fields=[bar1,bar2] seems fine, however i would personally leave off the brackets.
Google Compute Engine API uses the 'fields' request parameter (see the documentation). The syntax is flexible enough to let user select/restrict even the nested elements. You may find it useful.
Yoga is a framework that allows you to deploy your own REST API's with selectable fields. This can reduce roundtrips to the server, and improve performance.