AngularJs $http.post() does not send data

You can set the default "Content-Type" like this:

$http.defaults.headers.post["Content-Type"] = "application/x-www-form-urlencoded";

About the data format:

The $http.post and $http.put methods accept any JavaScript object (or a string) value as their data parameter. If data is a JavaScript object it will be, by default, converted to a JSON string.

Try to use this variation

function sendData($scope) {
    $http({
        url: 'request-url',
        method: "POST",
        data: { 'message' : message }
    })
    .then(function(response) {
            // success
    }, 
    function(response) { // optional
            // failed
    });
}

It's not super clear above, but if you are receiving the request in PHP you can use:

$params = json_decode(file_get_contents('php://input'),true);

To access an array in PHP from an AngularJS POST.

I had the same problem using asp.net MVC and found the solution here

There is much confusion among newcomers to AngularJS as to why the $http service shorthand functions ($http.post(), etc.) don’t appear to be swappable with the jQuery equivalents (jQuery.post(), etc.)

The difference is in how jQuery and AngularJS serialize and transmit the data. Fundamentally, the problem lies with your server language of choice being unable to understand AngularJS’s transmission natively ... By default, jQuery transmits data using

Content-Type: x-www-form-urlencoded

and the familiar foo=bar&baz=moe serialization.

AngularJS, however, transmits data using

Content-Type: application/json 

and { "foo": "bar", "baz": "moe" }

JSON serialization, which unfortunately some Web server languages—notably PHP—do not unserialize natively.

Works like a charm.

CODE

// Your app's root module...
angular.module('MyModule', [], function($httpProvider) {
  // Use x-www-form-urlencoded Content-Type
  $httpProvider.defaults.headers.post['Content-Type'] = 'application/x-www-form-urlencoded;charset=utf-8';
 
  /**
   * The workhorse; converts an object to x-www-form-urlencoded serialization.
   * @param {Object} obj
   * @return {String}
   */ 
  var param = function(obj) {
    var query = '', name, value, fullSubName, subName, subValue, innerObj, i;
      
    for(name in obj) {
      value = obj[name];
        
      if(value instanceof Array) {
        for(i=0; i<value.length; ++i) {
          subValue = value[i];
          fullSubName = name + '[' + i + ']';
          innerObj = {};
          innerObj[fullSubName] = subValue;
          query += param(innerObj) + '&';
        }
      }
      else if(value instanceof Object) {
        for(subName in value) {
          subValue = value[subName];
          fullSubName = name + '[' + subName + ']';
          innerObj = {};
          innerObj[fullSubName] = subValue;
          query += param(innerObj) + '&';
        }
      }
      else if(value !== undefined && value !== null)
        query += encodeURIComponent(name) + '=' + encodeURIComponent(value) + '&';
    }
      
    return query.length ? query.substr(0, query.length - 1) : query;
  };
 
  // Override $http service's default transformRequest
  $httpProvider.defaults.transformRequest = [function(data) {
    return angular.isObject(data) && String(data) !== '[object File]' ? param(data) : data;
  }];
});