Angular - convert HAL to JSON - json

Question

The following service extracts category objects from a REST service which returns them in HAL format. Now I try to convert that response into JSON. For that I searched and tried different solutions, e.g. chariotsolutions or so. Some are based on Response from '#angular/http' which is deprecated and which I cannot make work.
How can I do the conversion?
import { Injectable } from '#angular/core';
import { HttpClient, HttpHeaders } from '#angular/common/http';
import { Observable } from 'rxjs/Rx';
import { of } from 'rxjs/observable/of';
import 'rxjs/Rx';
import 'rxjs/add/operator/map';
import { Category } from './category';
#Injectable()
export class CategoryService {
private categoriesUrl = 'http://localhost:8080/account/categories';
constructor(private http: HttpClient) { }
getCategories(): Observable<Category[]> {
return this.http.get<Category[]>(this.categoriesUrl);
}
}
The response as HAL
{
"_embedded": {
"categories": [
{
"id": 1,
"name": "hardware",
"description": "comprises all computer hardware",
"level": "FIRST",
"_links": {
"self": {
"href": "http://localhost:8080/account/categories/1"
},
"categoryEntity": {
"href": "http://localhost:8080/account/categories/1"
}
}
},
{
"id": 2,
"name": "hardware_notebook",
"description": "all notebooks",
"level": "SECOND",
"_links": {
"self": {
"href": "http://localhost:8080/account/categories/2"
},
"categoryEntity": {
"href": "http://localhost:8080/account/categories/2"
}
}
}
]
},
"_links": {
"self": {
"href": "http://localhost:8080/account/categories{?page,size,sort}",
"templated": true
},
"profile": {
"href": "http://localhost:8080/account/profile/categories"
}
},
"page": {
"size": 20,
"totalElements": 8,
"totalPages": 1,
"number": 0
}
}

Answer 1

getCategories(): Observable<Category[]> {
return this.http.get<Category[]>(this.categoriesUrl)
.map((result:any)=>{
console.log(result); //<--it's an object
//result={"_embedded": {"categories": [..]..}
return result._embedded.categories; //just return "categories"
});
}
With Rjxs 6.0 we must use pipe(map)
getCategories(): Observable<Category[]> {
return this.http.get<Category[]>(this.categoriesUrl).pipe(
map((result:any)=>{
console.log(result); //<--it's an object
//result={"_embedded": {"categories": [..]..}
return result._embedded.categories; //just return "categories"
}));
}

Answer 2

Try following:
getCategories(): Observable<Category[]> {
return this.http.get<Category[]>(this.categoriesUrl).map((response)=>{
return response;
})
}