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Delphi DLL Requires Chilkat v11.5.0+

curl POST with JSON Input and JSON Output

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Demonstrates running a simple curl command with JSON input and JSON output.

Chilkat Delphi DLL Downloads

Delphi DLL
var
success: Boolean;
sbTargetCurl: HCkStringBuilder;
httpCurl: HCkHttpCurl;
responseJson: HCkJsonObject;
statusCode: Integer;
targetCurl: PWideChar;

begin
success := False;

//  Run the following curl command

//   curl -X POST https://httpbin.org/post \
//        -H "Content-Type: application/json" \
//        -d '{
//              "title": "foo",
//              "body": "bar",
//              "userId": 1
//            }'

//  The backslashes at the end of lines are not required.  Chilkat ignores them if present.
sbTargetCurl := CkStringBuilder_Create();
CkStringBuilder_AppendLn(sbTargetCurl,' curl -X POST https://httpbin.org/post \");
CkStringBuilder_AppendLn(sbTargetCurl,'      -H "Content-Type: application/json" \");
CkStringBuilder_AppendLn(sbTargetCurl,'      -d ''{');
CkStringBuilder_AppendLn(sbTargetCurl,'            "title": "foo",');
CkStringBuilder_AppendLn(sbTargetCurl,'            "body": "bar",');
CkStringBuilder_AppendLn(sbTargetCurl,'            "userId": 1');
CkStringBuilder_AppendLn(sbTargetCurl,'          }''');

httpCurl := CkHttpCurl_Create();

//  Run the curl command.
success := CkHttpCurl_DoYourThing(httpCurl,CkStringBuilder__getAsString(sbTargetCurl));
if (success = False) then
  begin
    Memo1.Lines.Add(CkHttpCurl__lastErrorText(httpCurl));
    Exit;
  end;

responseJson := CkJsonObject_Create();
CkJsonObject_putEmitCompact(responseJson,False);

CkHttpCurl_GetResponseJson(httpCurl,responseJson);

statusCode := CkHttpCurl_getStatusCode(httpCurl);
Memo1.Lines.Add('response status code: ' + IntToStr(statusCode));

Memo1.Lines.Add(CkJsonObject__emit(responseJson));

//  Output:

//  response status code: 200
//  {
//    "args": {},
//    "data": "{\r\n            \"title\": \"foo\",\r\n            \"body\": \"bar\",\r\n            \"userId\": 1\r\n          }",
//    "files": {},
//    "form": {},
//    "headers": {
//      "Content-Length": "96",
//      "Content-Type": "application/json",
//      "Host": "httpbin.org",
//      "X-Amzn-Trace-Id": "Root=1-69e8db8b-459b3bdf7b7a3bc749184968"
//    },
//    "json": {
//      "body": "bar",
//      "title": "foo",
//      "userId": 1
//    },
//    "origin": "123.222.222.222",
//    "url": "https://httpbin.org/post"
//  }

//  ----------------------------------------------------------------------------------
//  Another example:

//  curl -X POST https://postman-echo.com/post \
//       -H "Content-Type: application/json" \
//       -d '{"foo":"bar"}'

targetCurl := 'curl -X POST https://postman-echo.com/post -H "Content-Type: application/json" -d ''{"foo":"bar"}''';

//  Run the curl command.
success := CkHttpCurl_DoYourThing(httpCurl,targetCurl);
if (success = False) then
  begin
    Memo1.Lines.Add(CkHttpCurl__lastErrorText(httpCurl));
    Exit;
  end;

CkHttpCurl_GetResponseJson(httpCurl,responseJson);

statusCode := CkHttpCurl_getStatusCode(httpCurl);
Memo1.Lines.Add('response status code: ' + IntToStr(statusCode));

Memo1.Lines.Add(CkJsonObject__emit(responseJson));

//  Output:

//  response status code: 200
//  {
//    "args": {},
//    "data": {
//      "foo": "bar"
//    },
//    "files": {},
//    "form": {},
//    "headers": {
//      "host": "postman-echo.com",
//      "content-length": "13",
//      "content-type": "application/json",
//      "x-forwarded-proto": "https",
//      "accept-encoding": "gzip, br"
//    },
//    "json": {
//      "foo": "bar"
//    },
//    "url": "https://postman-echo.com/post"
//  }

CkStringBuilder_Dispose(sbTargetCurl);
CkHttpCurl_Dispose(httpCurl);
CkJsonObject_Dispose(responseJson);