Go Requires Chilkat v11.0.0+

JWS Using HMAC SHA-256

See more JSON Web Signatures (JWS) Examples

Creates a JSON Web Signatures (JWS) using HMAC SHA-256. Go

    success := false

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

    //  First create the JWS Protected Header
    jwsProtHdr := chilkat.NewJsonObject()
    jwsProtHdr.AppendString("typ","JWT")
    jwsProtHdr.AppendString("alg","HS256")
    fmt.Println("JWS Protected Header: ", *jwsProtHdr.Emit())

    //  Output:
    //  JWS Protected Header: {"typ":"JWT","alg":"HS256"}

    jws := chilkat.NewJws()

    //  Set the HMAC key:
    hmacKey := "AyM1SysPpbyDfgZld3umj1qzKObwVMkoqQ-EstJQLr_T-1qS0gZH75aKtMN3Yj0iPS4hcgUuTwjAzZr1Z9CAow"
    signatureIndex := 0
    jws.SetMacKey(signatureIndex,hmacKey,"base64url")

    //  Set the protected header:
    jws.SetProtectedHeader(signatureIndex,jwsProtHdr)

    //  Set the payload.
    bIncludeBom := false
    payloadStr := "In our village, folks say God crumbles up the old moon into stars."
    jws.SetPayload(payloadStr,"utf-8",bIncludeBom)

    //  Create the JWS
    //  By default, the compact serialization is used.
    jwsCompact := jws.CreateJws()
    if jws.LastMethodSuccess() == false {
        fmt.Println(jws.LastErrorText())
        jwsProtHdr.DisposeJsonObject()
        jws.DisposeJws()
        return
    }

    fmt.Println("JWS: ", *jwsCompact)

    //  sample output:
    //  JWS: eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.SW4gb3VyIHZpbGxhZ2UsIGZvbGtzIHNheSBHb2QgY3J1bWJsZXMgdXAgdGhlIG9sZCBtb29uIGludG8gc3RhcnMu.bsYsi8HJ0N6OqGI1hKQ9QQRNPxxA5qMpcHLtOvXatk8

    //  Now load the JWS, validate, and recover the original text.
    jws2 := chilkat.NewJws()

    //  Load the JWS.
    success = jws2.LoadJws(*jwsCompact)

    //  Set the MAC key used for validation.
    signatureIndex = 0
    jws2.SetMacKey(signatureIndex,hmacKey,"base64url")

    //  Validate the 1st (and only) signature at index 0..
    v := jws2.Validate(signatureIndex)
    if v < 0 {
        //  Perhaps Chilkat was not unlocked or the trial expired..
        fmt.Println("Method call failed for some other reason.")
        fmt.Println(jws2.LastErrorText())
        jwsProtHdr.DisposeJsonObject()
        jws.DisposeJws()
        jws2.DisposeJws()
        return
    }

    if v == 0 {
        fmt.Println("Invalid signature.  The MAC key was incorrect, the JWS was invalid, or both.")
        jwsProtHdr.DisposeJsonObject()
        jws.DisposeJws()
        jws2.DisposeJws()
        return
    }

    //  If we get here, the signature was validated..
    fmt.Println("Signature validated.")

    //  Recover the original content:
    fmt.Println(*jws2.GetPayload("utf-8"))

    //  Examine the protected header:

    joseHeader := chilkat.NewJsonObject()
    success = jws2.GetProtectedH(signatureIndex,joseHeader)
    if success == false {
        fmt.Println(jws2.LastErrorText())
        jwsProtHdr.DisposeJsonObject()
        jws.DisposeJws()
        jws2.DisposeJws()
        joseHeader.DisposeJsonObject()
        return
    }

    joseHeader.SetEmitCompact(false)

    fmt.Println("Protected (JOSE) header:")
    fmt.Println(*joseHeader.Emit())

    //  Output:

    //  	Signature validated.
    //  	In our village, folks say God crumbles up the old moon into stars.
    //  	Protected (JOSE) header:
    //  	{ 
    //  	  "typ": "JWT",
    //  	  "alg": "HS256"
    //  	} 

    jwsProtHdr.DisposeJsonObject()
    jws.DisposeJws()
    jws2.DisposeJws()
    joseHeader.DisposeJsonObject()