The HAL spec that I am working with says that you can have multiple links of the same type on a resource like this:
{
"_links": {
"items": [{
"href": "/first_item"
},{
"href": "/second_item"
}]
}
}
However Spring ResourceSupport type only seems to have an add() method that adds a single link. So I can write
order.add(linkTo(methodOn(OrderController.class).order(id)).withRel("item"));
to add one such, but I can't see how to get an array of them with a ref as items, as per the spec.
If you call ResourceSupport::add() twice (or more) with the same withRel value, it creates an array ref with that name containing each of the items.
Related
I'm working on a "global search" for my application.
Currently, I'm using hibernate-search to search for instances of multiple different objects and return them to the user.
The relevant code looks as follows:
Search.session(entityManager)
.search(ModelA.classs, ModelB.class)
.where(...)
.sort(...)
.fetch(skip, count);
Skip and count are calculated based on a Pageable and the result is used to create an instance of Page, which will be returned to the controller.
This works as I'd expect, however, the types generated by swagger-docs obviously doesn't know, what the type within the Page is, and therefore uses Object.
I'd like to expose the correct types, as I use them to generate the types for the frontend application.
I was able to set the type to an array, when overwriting the schema like this:
#ArraySchema(schema = #Schema(anyOf = {ModelA.class, ModelB.class}))
public Page<?> search(Pageable pageable) {
However, this just disregards the Page and also isn't correct.
The next thing I tried is extending the PageImpl, overwriting the getContent method, and specifying the same schema on this method, but this wasn't included in the output at all.
Next was implementing Page<T> myself (and later removing the implements reference to Page<T>) and specifying the same schema on getContent, iterator, and the field itself, but also to no effect.
How do I tell spring-docs, what the content of the resulting Page might be?
I stumbled upon this when trying to solve a similar problem
Inspired from this thread Springdoc with a generic return type i came up with the following solution, and it seems to apply to your case also. Code examples are in Kotlin.
I introduced a stub class that will just act as the Schema for the response:
private class PageModel(
#Schema(oneOf = [ModelA::class, ModelB::class]))
content: List<Object>
): PageImpl<Object>(content)
Then i annotated my Controller like this:
#Operation(
responses = [
ApiResponse(
responseCode = "200",
content = [Content(schema = Schema(implementation = PageModel::class))]
)
]
)
fun getPage(pageable: Pageable): Page<Object>
This generated this api response:
"PageModel": {
"properties": {
"content": {
"items": {
"oneOf": [
{
"$ref": "#/components/schemas/ModelA"
},
{
"$ref": "#/components/schemas/ModelB"
}
],
"type": "object"
},
"type": "array"
},
... -> more page stuff from spring's PageImpl<>
And in the "responses" section for the api call:
"responses": {
"200": {
"content": {
"application/json": {
"schema": {
"$ref": "#/components/schemas/PageModel"
}
}
},
"description": "OK"
}
All generated openapi doc is similar to the autogenerated json when returning a Page, it just rewrites the "content" array property to have a specific type.
I am building a GraphQL Schema that has a Type Pod which contains 3 nested objects.
type Pod {
metadata: Metadata
spec: Spec
status: Status
}
My data source is an external API which returns an array of this data. In fact, I defined my schema around this API response. I have included a trimmed down version below.
[
{
"metadata": {
"name": "my-app-65",
"namespace": "default",
},
"spec": {
"containers": [
{
"name": "hello-world",
"image": "container-image.io/unique-id",
}
],
},
// more like-objects in the array
]
However, for each of these container objects, inside the array. I would like to add some extra information which this initial API call does not provide. However, I can query this information separately if I provide the name & namespace properties on the parent's metadata.
/container/endpoint/${namespace}/${name}
Returns...
[ {
name: "hello-world",
nestObj: {
//data
}
},
]
And I would like to add this nested Obj to the original space when that data is queried.
However, I don't have a clean way to access the pod.metadata.name inside the resolver for Container.
Currently my resolvers look like....
Query: {
pods: async () => {
//query that returns array of pod objects
return pods
}
},
Container: {
name: "hello-world",
nestedObj: async (parent, args, context, info) => {
//query that hits the second endpoint but requires name & namespace.
//however, I don't have access to those values.
}
}
Perfect world solution: I could access parent.parent.metadata.name inside the Container Resolver
Current Approach (brute force, repetitively add the property to the children)
Loop through every nested container objs in every Pod and add the podName & namespace as properties there.
pods.forEach(pod => pod.spec.containers.forEach(container => {
container.podName = pod.metadata.name;
container.namespace = pod.metadata.namespace;
}))
This feels very much like a hack, and really bogs down my query times. Especially considering this data won't always be requested.
I have two intuitive ideas but don't know how to implement them (I'm a bit new to graphQL).
Implement a Pod resolver that would then pass this data in through the rootValue as described here: https://github.com/graphql/graphql-js/issues/1098
Access it somewhere inside the info object
The problem the first one, is that my data source only sends me the data as an array, not individual pods and I'm unsure how to pass that array of data into resolvers for individual components.
The problem with second, is that object is very dense. I tried accessing it via the path. But path seems to only store the type, not the actual data.
It's also possible I'm just implementing this completely wrong and welcome such feedback.
Thanks for any guidance, suggestions, or resources.
I have a power app that using the flow from power automate.
My flow is doing an HTTP get and respond a JSON to power apps like below.
Here is the JSON as text:
{"value": "[{\"dataAreaId\":\"mv\",\"AccountNum\":\"100000\",\"Name\":\"*****L FOOD AB\"},{\"dataAreaId\":\"mv\",\"AccountNum\":\"100001\",\"Name\":\"**** AB\"},{\"dataAreaId\":\"mv\",\"AccountNum\":\"100014\",\"Name\":\"****(SEB)\"},{\"dataAreaId\":\"mv\",\"AccountNum\":\"100021\",\"Name\":\"**** AB\"},{\"dataAreaId\":\"mv\",\"AccountNum\":\"100029\",\"Name\":\"**** AB\"},{\"dataAreaId\":\"mv\",\"AccountNum\":\"500100\",\"Name\":\"**** AB\"},{\"dataAreaId\":\"mv\",\"AccountNum\":\"500210\",\"Name\":\"****\"}]"}
But when I try to convert this JSON to the collection, It doesn't behave like a list.
It just seems like a text. Here is how I try to bind the list.
How can I create a collection from JSON to bind to the gallery view?
I found the solution. I finally create a collection from the response of flow.
The flow's name is GetVendor.
The response of flow is like this :
{"value": "[{\"dataAreaId\":\"mv\",\"AccountNum\":\"100000\",\"Name\":\"*****L FOOD AB\"},{\"dataAreaId\":\"mv\",\"AccountNum\":\"100001\",\"Name\":\"**** AB\"},{\"dataAreaId\":\"mv\",\"AccountNum\":\"100014\",\"Name\":\"****(SEB)\"},{\"dataAreaId\":\"mv\",\"AccountNum\":\"100021\",\"Name\":\"**** AB\"},{\"dataAreaId\":\"mv\",\"AccountNum\":\"100029\",\"Name\":\"**** AB\"},{\"dataAreaId\":\"mv\",\"AccountNum\":\"500100\",\"Name\":\"**** AB\"},{\"dataAreaId\":\"mv\",\"AccountNum\":\"500210\",\"Name\":\"****\"}]"}
Below code creates a list from this response :
ClearCollect(_vendorData, MatchAll(GetVendors.Run(_token.value).value, "\{""dataAreaId"":""(?<dataAreaId>[^""]*)"",""AccountNum"":""(?<AccountNum>[^""]*)"",""Name"":""(?<Name>[^""]*)""\}"));
And I could bind the accountnum and name from _vendorDatra collection to the gallery view
In my case I had the same issue as you, but couldn't manage to get data into _vendorData collection, because MatchAll regex part was not working correctly, even if I had exactly the same scenario and I could not make it work.
My solution was to modify the flow itself, where I returned Response instead of Respond to a Power app or Flow, so basically I could return full request from Http.
This caused me some issues also, because when I generated schema from sample I could not register the flow to the powerapp with the error Failed during http send request.
The solution was to manually review the response schema and change all column types to one of the following three, because other are not supported: string, integer or boolean. Object and array can be set only on top level items, but never on children, so if you have anything else than my mentioned three, replace it to string. And no property can be left with undefined type.
Basically I like this solution even more, because in powerapps itself you do not need to do any conversion or anything - simply use the data as is, because it is already recognized as collection in case of array and you have all the properties already named for you.
Response step schema example is below.
{
"type": "object",
"properties": {
"PropertyOne": {
"type": "string"
},
"PropertyTwo": {
"type": "integer"
},
"PropertyThree": {
"type": "boolean"
},
"PropertyFour": {
"type": "array",
"items": {
"type": "object",
"properties": {
"PropertyArray1": {
"type": "string"
},
"PropertyArray1": {
"type": "integer"
},
"PropertyArray1": {
"type": "boolean"
}
}
}
It is easy now.
Power Apps introduced ParseJSON function which helps converting string to collection easily.
Table(ParseJSON(JSONString));
In gallery, map columns like - ThisItem.Value.ColumnName
This sounds like a rookie question, but I'm wondering what's the best way to present paged resources with HAL format? Right now I'm using Spring HATEOAS API to convert Page object into resource PagedResourcesAssembler#toResource(Page<T>, ResourceAssembler<T,R>). This results in the following output:
{
"_links": {
"self": {
"href": "http://example.org/api/user?page=3"
},
…
}
"count": 3,
"total": 498,
"_embedded": {
"users": [
{
"_links": {
"self": {
"href": "http://example.org/api/user/mwop"
}
},
"id": "mwop",
"name": "Matthew Weier O'Phinney"
}
]
}
}
Everything works fine but the only problem is the collection being returned is under _embedded field and has the class name, so the client has to know this class name as well right? Would it be better to just return the collection under content like non-HAL format? If yes how should I achieve it using Spring HATEOAS?
That's not a problem, that's the way _embedded is defined in the HAL specification.
users is not a class, it's a link relation that will allow clients to actually find the collection it was asking for in the first place (e.g. using a JSONPath expression). That's not something coming out of the blue at all but usually is the same link relation, the client used to find that resource in the first place.
Assume an API root exposing this document:
{
"_links": {
"users": {
"href": "…"
},
…
}
}
Seeing that, the client would have to know the semantics of users to find the link it wants to follow. In your case users is basically pointing to a collection resource that supports pagination.
So if the client follows the link named users, it can then find the actual content it's looking for under _embedded.users in the HAL response by combining knowledge about the media type (HAL, _embedded) and the service's application-level semantics (users).
I am pretty new in Spring and in REST web services and I have the following dout following a tutorial that show how to implement a RESTful web service using Spring MVC.
So, into a controller class I have this method:
#Controller
#RequestMapping("/api/categories")
public class CategoryRestController {
#RequestMapping
#ResponseBody
public CategoryList getCategories(#RequestParam("start") int start, #RequestParam("size") int size ) {
List<Category> categoryEntries = categoryService.findCategoryEntries(start, size);
return new CategoryList(categoryEntries);
}
}
This method handle HTTP GET request toward the resoruce /api/categories and return the retrieved list into JSON format (I think that it depends by the content negotiazion: if the caller put the Accept header as JSON the method return the result in JSON format, is it right?)
By the way my doubt is related the HTTP request shown in the tutorial, infact it do:
http://localhost:8080/springchocolatestore/api/categories?start=0&size=2
that is handled by the previous controller method to return a paginated list (that could be hude) in JSON format, infact I retrieve the following output:
{
"categories": [
{
"links": [
{
"rel": "self",
"href": "http://localhost:8080/springchocolatestore/api/categories/1",
"variables": [],
"templated": false,
"variableNames": []
}
],
"name": "Truffles",
"description": "Truffles",
"id": {
"rel": "self",
"href": "http://localhost:8080/springchocolatestore/api/categories/1",
"variables": [],
"templated": false,
"variableNames": []
}
},
{
"links": [
{
"rel": "self",
"href": "http://localhost:8080/springchocolatestore/api/categories/2",
"variables": [],
"templated": false,
"variableNames": []
}
],
"name": "Belgian Chocolates",
"description": "Belgian Chocolates",
"id": {
"rel": "self",
"href": "http://localhost:8080/springchocolatestore/api/categories/2",
"variables": [],
"templated": false,
"variableNames": []
}
}
]
}
Ok, so in the request I specify the pagination parameter by categories?start=0&size=2
My doubt is related to the user of this parameter. From what I have understand (but maybe it could be wrong) the use of the parameter is against the RESTful principles. Is it true or am I mising something?
Or maybe in this specific case are valid because the parameter are not specifing an object (that have to be returned into my JSON output) but are only related to some options?
I mean that maybe I can't use parameter to specify a specific object, something like this:
// RETRIEVE THE PRODUCT WITH ID=1
http://localhost:8080/springchocolatestore/api/producs?product=1
So I think that the previous is not following the RESTfull standard because I am specifing a product object with a parameter and not accessing to it as a resource, so I have to do in this way:
http://localhost:8080/springchocolatestore/api/producs/1
Can you give me some clarification?
Tnx
REST doesn't have much to do with URLs, and using request parameters is not unRESTful.
But I agree that path variables are generally used to identify a specific resource, and parameters are generally used for search or pagination parameters.