C

ITIDA Canonicalize JSON and Compute SHA256 Hash

See more Egypt ITIDA Examples

Demonstrates creating the canonical (ITIDA) version of a JSON document, and then computes the SHA256 hash of the canonicalized JSON. C

#include <C_CkStringBuilder.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkStringBuilder sb;

    success = FALSE;

    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // Load the JSON containing the document to be signed.

    // The JSON file should look like this:
    // NOTE: The JSON should NOT begin with "{ "documents" : [ ..."

    //       {
    //          "issuer":{
    //             "address":{
    //                "branchID":"0",
    //                "country":"EG",
    //                "regionCity":"Cairo",
    //                "postalCode":"",
    //                "buildingNumber":"0",
    //                "street":"123rd Street",
    //                "governate":"GOVERNATE"
    //             },
    //             "type":"B",
    //             "id":"209999899",
    //             "name":"Xyz SAE"
    //          },
    // ...
    // ...

    sb = CkStringBuilder_Create();
    success = CkStringBuilder_LoadFile(sb,"my_invoice.json","utf-8");
    if (success == FALSE) {
        printf("Failed to load input file.\n");
        CkStringBuilder_Dispose(sb);
        return;
    }

    // Convert the contents of sb to the ITIDA canonical form.
    // Always pass utf-8 for the 2nd arg.
    CkStringBuilder_Encode(sb,"itida","utf-8");

    // Examine the canonicalized JSON
    printf("%s\n",CkStringBuilder_getAsString(sb));

    // Compute the SHA256 hash and show the SHA256 in hex format
    printf("SHA256 hash: %s\n",CkStringBuilder_getHash(sb,"sha256","hex","utf-8"));


    CkStringBuilder_Dispose(sb);

    }