(Go) Walmart Partner API Authentication (Generate a Signature for a Request)

Demonstrates how to generate a signature for a Walmart Partner REST API call.

Chilkat Go Downloads Go Package for Windows, MacOS, Linux, Alpine Linux, Solaris

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

    var success bool

    consumerId := "b68d2a72...."
    baseUrl := "https://marketplace.walmartapis.com/v2/feeds"
    // This is your Base64 encoded private key
    privateEncodedStr := "MIICeAIBADANBgkqhkiG9w0BAQEFAA......"
    httpMethod := "GET"

    // We need a timestamp in decimal string form representing the number of milliseconds since Jan 01 1970 UTC.
    dt := chilkat.NewCkDateTime()
    // Set bLocal = true for a timestamp in the local timezone.  Set bLocal = false for a UTC timestamp.
    bLocal := false
    // This gets the timestamp in seconds, not milliseconds.
    timeStampVal := dt.GetAsUnixTime(bLocal)

    // Build the string to sign.
    sbStringToSign := chilkat.NewStringBuilder()
    sbStringToSign.Append(consumerId)
    sbStringToSign.Append("\n")
    sbStringToSign.Append(baseUrl)
    sbStringToSign.Append("\n")
    sbStringToSign.Append(httpMethod)
    sbStringToSign.Append("\n")
    sbStringToSign.AppendInt(timeStampVal)
    // We add three zero's so that the timestamp value is in milliseconds.
    // We don't care about accuracy down to less than a second.
    // All the server cares about is that the request was signed at the current date/time
    // within some reasonable margin of error (to account for systems having clocks
    // that may be slightly different).
    sbStringToSign.Append("000\n")

    privKey := chilkat.NewPrivateKey()
    // Load the private key into a private key object.
    // Note: Technically the private key is not PEM because it lacks the header/footer strings
    // used for PEM.  However, the LoadPem method will still accept it and load it correctly.
    success = privKey.LoadPem(privateEncodedStr)
    if success != true {
        fmt.Println(privKey.LastErrorText())
        dt.DisposeCkDateTime()
        sbStringToSign.DisposeStringBuilder()
        privKey.DisposePrivateKey()
        return
    }

    rsa := chilkat.NewRsa()
    success = rsa.ImportPrivateKeyObj(privKey)
    if success != true {
        fmt.Println(rsa.LastErrorText())
        dt.DisposeCkDateTime()
        sbStringToSign.DisposeStringBuilder()
        privKey.DisposePrivateKey()
        rsa.DisposeRsa()
        return
    }

    // We want a base64 signature string.
    rsa.SetEncodingMode("base64")

    signatureString := rsa.SignStringENC(*sbStringToSign.GetAsString(),"SHA256")
    if rsa.LastMethodSuccess() != true {
        fmt.Println(rsa.LastErrorText())
        dt.DisposeCkDateTime()
        sbStringToSign.DisposeStringBuilder()
        privKey.DisposePrivateKey()
        rsa.DisposeRsa()
        return
    }

    fmt.Println("Signature String: ", *signatureString)

    dt.DisposeCkDateTime()
    sbStringToSign.DisposeStringBuilder()
    privKey.DisposePrivateKey()
    rsa.DisposeRsa()