Converting JSON responses from Observables to Arrays of objects in Angular

I have created a custom interface called Table which defines the structure of my data.

export interface Table {
    id: number;
    title: string;
    status: string;
    level: string;
    description: string;
}

In my service, I am using HttpClient to send a GET request to retrieve data from the backend server.

public tables: Array<Table>;

public getTables(): Observable<Table[]> { 
    return this.http.get<Table[]>(this.endpoint + 'get-tables');
}

Within my page controller, I am invoking the service function and aiming to convert the JSON response into an array of objects that match the interface 'Table'.

this.tableService.getTables().subscribe((response: Table[]) => {
    this.tableService.tables = response;
});

Despite expecting the JSON response to be converted into an array of objects, I am not seeing the desired result in my 'tables' array. Any idea what might be causing this issue?

Your assistance in troubleshooting why the conversion is not occurring as expected would be greatly appreciated.

Answer №1

Before proceeding, ensure you initialize your Table Array with this snippet:

   public tables!: Table[];

    public getTables(): Observable<Table[]> { 
         return this.http.get<Table[]>(this.endpoint + 'get-tables');
    }

The presence of the ! (exclamation mark) is crucial when operating in strict mode. It signifies that a variable declared within a class must be initialized. However, this is just a footnote to consider.

If the above code does not yield results, kindly share the response JSON from the server. But if the structure resembles something like this:_

[
  {
    id: xxx,
    name: xxx,
  },
  ...
]

Then it should seamlessly integrate with my code.

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