How to set the request body via Postman's pre-request script?

Question

I use Postman 6.0 to send an HTTP request. To send a request, I use a pre-request script to get a token and put it into the environment so that it will be used in the succeeding requests.

The script below doesn't work because the body is not sent. Is there anything wrong with the script below?

const getTaxAccessToken={
  url: 'http://dev.xxx.com:4001/api/v1/portal/account/tax-login',
  method: "post",
  body: {
      'loginIdentity': 'admic',
      'password': 'abc123'
  },
  header: {
      'Content-Type': 'application/json'
  }
};
pm.sendRequest(getTaxAccessToken, function (err, response) {
  console.log("get accesstoken");
  console.log(response.access_Token);
  pm.environment.set("taxAccessToken", response.access_Token);
});

Answer 1

Try this.

  body: {
     mode: 'raw',
     raw: JSON.stringify({'loginIdentity': 'admic', 'password': 'abc123'})
  }

Answer 2

If the request needs to be of type application/x-www-form-urlencoded:

const options = {
  url:  'http://some/url', 
  method: 'POST',
  header: {
    'Accept': '*/*',
    'Content-Type': 'application/x-www-form-urlencoded',
  },
  body: {
    mode: 'urlencoded',
    urlencoded : [
      { key: 'loginIdentity', value: 'admic'},
      { key: 'password', value: 'abc123'},
    ]
  }
};

pm.sendRequest(options, function (err, res) {
  // ...
});

Postman Javascript API references:

• Request
• RequestBody