An error is triggered when an HttpClient post does not return any data

Question

An error is triggered when an HttpClient post does not return any data

While sending a post request from my angular application to a web api, I am encountering an issue. The response from the api is supposed to be either a 200 status or a 404 status without any data being returned. An example of some headers for the 200 response are

{ "content-length": "0", "content-type": null }

. Here is the block of Typescript code responsible for making the post request:

return this.http.post(url, "", { params: params }).catch(err => {
        console.log(err);
        throw "";
    });

The problem arises when I receive an error even for the 200 response with the message: Unexpected end of JSON input.

How can I properly handle and evaluate the response code in order to accurately determine success (return true) or failure (return false)?

angular typescript observable

Answer 1

Answer №1

Utilize syntax similar to the following example and include the header parameters.

let headers = new Headers({ 'Authorization': 'Bearer token' });
        let options = new RequestOptions({ headers: headers });
        return this.httpClient.post(this.apiUrl, {data:data}, options)
                   .map(this.formatData) //your data formatting
                   .catch(this.handleErrors);
    }

Answer 2

Utilize syntax similar to the following example and include the header parameters.

let headers = new Headers({ 'Authorization': 'Bearer token' });
        let options = new RequestOptions({ headers: headers });
        return this.httpClient.post(this.apiUrl, {data:data}, options)
                   .map(this.formatData) //your data formatting
                   .catch(this.handleErrors);
    }

Answer 3

Answer №2

It seems like you may have overlooked the subscribe method, as you have not accounted for the success callback. If you are working with HttpClient, use Subscribe instead of map. However, if you are using Http, then go ahead and use map.

I would recommend utilizing HttpClient, which is a new feature introduced in angular 4.3.X, offering various powerful methods for different tasks.

this.http.post(url, "", { params: params }).subscribe(response =>{this.postResult = response; console.log(response);}, error=>{ console.log(error); throw "";});

Answer 4

It seems like you may have overlooked the subscribe method, as you have not accounted for the success callback. If you are working with HttpClient, use Subscribe instead of map. However, if you are using Http, then go ahead and use map.

I would recommend utilizing HttpClient, which is a new feature introduced in angular 4.3.X, offering various powerful methods for different tasks.

this.http.post(url, "", { params: params }).subscribe(response =>{this.postResult = response; console.log(response);}, error=>{ console.log(error); throw "";});

An error is triggered when an HttpClient post does not return any data

Answer №1

Answer №2

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