How to access Dart shelf post body parameters?

Question

I am using Dart Shelf framework for building an API. Get works fine but I am having issues with post. I couldn't access any of the body parameters of the post request in my server. Here is what I have tried.

// shelf-router
router.post('/login', (Request req) async {
  final body = await req.readAsString();
// to check
 print(body); // outputs null
 return 
 Response.ok('OK');
});

How am I testing this?

Using postman with the endpoint and body type raw (JSON).

payload as

{
  "user":"testUser",
  "password":"p455w0rd"
}

I even tried setting contenttype header to application/JSON but no luck there too.

I assume "outputs null" actually means "outputs the empty string"? (`Request.readAsString` is declared to return a `Future` that completes to a non-nullable type.) What is `router.post`? Are you sure that the `Request` hasn't already been read (per [the documentation](https://pub.dev/documentation/shelf/latest/shelf/Request/readAsString.html), it can be called only once)? Could you possibly create a minimal, reproducible example? — jamesdlin, Mar 27 '22 at 11:45
Did you solve your problem? You never updated your question. — jamesdlin, Apr 07 '22 at 05:33
Unfortunately no, I've given up on getting post data using shelf. I am now sending passwords, sadly, using get, encoded in the url. — GunJack, Apr 08 '22 at 06:54

score 2 · Answer 1 · answered Oct 22 '22 at 15:35

2

final String query = await request.readAsString();
// Map<String, String> queryParams = Uri(query: query).queryParameters;
Map queryParams = jsonDecode(query);
print(queryParams['user']);

answered Oct 22 '22 at 15:35

Rubens Galvan

21
2

readAsString() does not return the parameters. Instead returns an empty string. – Izac Mac Dec 05 '22 at 03:50

score 1 · Answer 2 · answered Aug 21 '22 at 13:24

1

Try this inside your request handler function..

final String query = await request.readAsString();
Map queryParams = Uri(query: query).queryParameters;
print(queryParams);

answered Aug 21 '22 at 13:24

Darshil Patel

21
4

Sittiphan Sittisak · Answer 3 · 2022-12-01T04:34:32.950

0

I can receive the parameter from the postman with form-data. I am using shelf_route in the server. If this is similar to you, you can follow this: https://stackoverflow.com/a/74255231/17798537

edited Dec 01 '22 at 04:34

answered Dec 01 '22 at 04:27

Sittiphan Sittisak

486
4
15

score 0 · Answer 4 · answered Apr 16 '23 at 10:37

0

For the body params

var bodyString = await request.readAsString();
var body = json.decode(bodyString);

For query param

var query = request.url.queryParameters

answered Apr 16 '23 at 10:37

A J

191
3
4

How to access Dart shelf post body parameters?

4 Answers4