Delphi DLL Requires Chilkat v11.1.0+

Creating an application/json HTTP POST Request

See more HTTP Examples

Demonstrates how to create an HTTP POST request having the Content-Type application/json, where the body of the HTTP request is the following JSON:

{
   "username" : "my_username",
   "password" : "my_password",
   "validation-factors" : {
      "validationFactors" : [
         {
            "name" : "remote_address",
            "value" : "127.0.0.1"
         }
      ]
   }
}

The generated HTTP request looks like this:

POST /something HTTP/1.1
Content-Type: application/json
Accept: application/json
Host: domain
Content-Length: 216

{
  "username": "my_username",
  "password": "my_password",
  "validation-factors": {
    "validationFactors": [
      {
        "name": "remote_address",
        "value": "127.0.0.1"
      }
    ]
  }
}

Delphi DLL

var
req: HCkHttpRequest;
json: HCkJsonObject;
vFactors: HCkJsonObject;
vArray: HCkJsonArray;
factorObj: HCkJsonObject;
requestMime: PWideChar;

begin
//  This example demonstrates building an application/json request.

req := CkHttpRequest_Create();

//  The ContentType, HttpVerb, and Path properties should
//  always be explicitly set.
CkHttpRequest_putHttpVerb(req,'POST');
CkHttpRequest_putPath(req,'/something');
CkHttpRequest_putContentType(req,'application/json');

//  We may wish to add an "Accept" header to the request.
//  This tells the server we'll accept an application/json response.
CkHttpRequest_AddHeader(req,'Accept','application/json');

//  We'll use Chilkat's JSON API to create the JSON body of the HTTP request.
json := CkJsonObject_Create();
CkJsonObject_AppendString(json,'username','my_username');
CkJsonObject_AppendString(json,'password','my_password');

vFactors := CkJsonObject_Create();
CkJsonObject_AppendObject2(json,'validation-factors',vFactors);

vArray := CkJsonArray_Create();
CkJsonObject_AppendArray2(vFactors,'validationFactors',vArray);

factorObj := CkJsonObject_Create();
CkJsonArray_AddObjectAt2(vArray,0,factorObj);
CkJsonObject_AppendString(factorObj,'name','remote_address');
CkJsonObject_AppendString(factorObj,'value','127.0.0.1');

//  Use the JSON for the HTTP request body
//  By default, the Emit method will output compact JSON.
//  This is best for generating the smallest size request.
//  To generate a more human-readable (pretty-printed) JSON request body,
//  set the EmitCompact property to FALSE
CkJsonObject_putEmitCompact(json,False);
CkHttpRequest_LoadBodyFromString(req,CkJsonObject__emit(json),'utf-8');

//  View the request that would be sent if HttpSReq was called:
requestMime := CkHttpRequest__generateRequestText(req);
Memo1.Lines.Add(requestMime);

//  A few important comments about the HTTP request that is generated:
//  
//  1) The Content-Length header is automatically generated based on the actual length of the MIME message
//     that follows the intial (topmost) MIME header.
//  2) The HOST header will automatically get filled in with the actual domain when HttpSReq
//     is called.

CkHttpRequest_Dispose(req);
CkJsonObject_Dispose(json);
CkJsonObject_Dispose(vFactors);
CkJsonArray_Dispose(vArray);
CkJsonObject_Dispose(factorObj);