Ways to manage an rxjs observable reaction that may potentially have no data?

Currently, I am working with Angular2 and Ionic2 using typescript and have a requirement to manage responses from the backend service.

  • The response may either be empty with http status 200
  • or it could be a json object containing an error message property that needs to be shown to the user.

This is how I'm sending my request:

this.http.put(***).subscribe((data) => {

The challenge I'm facing is that when the data parameter is provided, rxjs attempts to serialize it from JSON, causing an error if it's empty. On the other hand, if I don't provide the data parameter, I can handle the empty response but then how do I access the error message property if it exists?

I prefer not to make any changes on the backend side to ensure proper http error codes in case of an error. Is there a solution to deal with this situation?

angulartypescriptionic-frameworkrxjs

Answer №1

Have you attempted a similar approach as shown below?

const updateItem = (item: any): Observable<Response> => {
    return this._http
        .put("http://localhost/api/", JSON.stringify(item))
        .map(response => response ? response.json() : {});
}

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