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C

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 C Downloads

C
#include <C_CkStringBuilder.h>
#include <C_CkHttpCurl.h>
#include <C_CkJsonObject.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkStringBuilder sbTargetCurl;
    HCkHttpCurl httpCurl;
    HCkJsonObject responseJson;
    int statusCode;
    const char *targetCurl;

    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) {
        printf("%s\n",CkHttpCurl_lastErrorText(httpCurl));
        CkStringBuilder_Dispose(sbTargetCurl);
        CkHttpCurl_Dispose(httpCurl);
        return;
    }

    responseJson = CkJsonObject_Create();
    CkJsonObject_putEmitCompact(responseJson,FALSE);

    CkHttpCurl_GetResponseJson(httpCurl,responseJson);

    statusCode = CkHttpCurl_getStatusCode(httpCurl);
    printf("response status code: %d\n",statusCode);

    printf("%s\n",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) {
        printf("%s\n",CkHttpCurl_lastErrorText(httpCurl));
        CkStringBuilder_Dispose(sbTargetCurl);
        CkHttpCurl_Dispose(httpCurl);
        CkJsonObject_Dispose(responseJson);
        return;
    }

    CkHttpCurl_GetResponseJson(httpCurl,responseJson);

    statusCode = CkHttpCurl_getStatusCode(httpCurl);
    printf("response status code: %d\n",statusCode);

    printf("%s\n",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);

    }