(Go) Sign Manifest File to Generate a Passbook .pkpass in Memory

Demonstrates how to create a Passbook .pkpass archive by creating a signature of a manifest file and then zipping to a .pkpass archive in memory

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

    // ---------------------------------------------------------------------------------------------
    // This example is the same as Sign Manifest File to Generate a Passbook .pkpass file
    // except everything happens in memory (no input files, no output files)
    // ---------------------------------------------------------------------------------------------

    // First create the manifest.json
    var success bool
    manifest := chilkat.NewJsonObject()
    crypt := chilkat.NewCrypt2()

    zip := chilkat.NewZip()
    zip.NewZip("notUsedAndNeverCreated.zip")

    crypt.SetHashAlgorithm("sha1")
    // Return hashes as lowercase hex.
    crypt.SetEncodingMode("hexlower")

    var digestStr *string = new(string)

    pngData := chilkat.NewBinData()
    // Assume we load the pngData with bytes for "icon.png" from somewhere, such as a byte array in memory.
    entry := zip.AppendBd("icon.png",pngData)
    entry.DisposeZipEntry()
    digestStr = crypt.HashBdENC(pngData)
    manifest.UpdateString("\"icon.png\"",*digestStr)

    pngData.Clear()
    // Assume we load the pngData with bytes for "icon@2x.png" from somewhere...
    entry = zip.AppendBd("icon@2x.png",pngData)
    entry.DisposeZipEntry()
    digestStr = crypt.HashBdENC(pngData)
    manifest.UpdateString("\"icon@2x.png\"",*digestStr)

    pngData.Clear()
    // Assume we load the pngData with bytes for "logo.png" from somewhere...
    entry = zip.AppendBd("logo.png",pngData)
    entry.DisposeZipEntry()
    digestStr = crypt.HashBdENC(pngData)
    manifest.UpdateString("\"logo.png\"",*digestStr)

    pngData.Clear()
    // Assume we load the pngData with bytes for "logo@2x.png" from somewhere...
    entry = zip.AppendBd("logo@2x.png",pngData)
    entry.DisposeZipEntry()
    digestStr = crypt.HashBdENC(pngData)
    manifest.UpdateString("\"logo@2x.png\"",*digestStr)

    passJson := "{ .... }"    //  Contains the contents of pass.json
    entry = zip.AppendString("pass.json",passJson)
    entry.DisposeZipEntry()
    digestStr = crypt.HashStringENC(passJson)
    manifest.UpdateString("\"pass.json\"",*digestStr)

    entry = zip.AppendString("manifest.json",*manifest.Emit())
    entry.DisposeZipEntry()

    // Make sure we have the Apple WWDR intermediate certificate available for 
    // the cert chain in the signature.
    certVault := chilkat.NewXmlCertVault()
    appleWwdrCert := chilkat.NewCert()
    success = appleWwdrCert.LoadByCommonName("Apple Worldwide Developer Relations Certification Authority")
    if success != true {
        fmt.Println("The Apple WWDR intermediate certificate is not installed.")
        fmt.Println("It is available at https://developer.apple.com/certificationauthority/AppleWWDRCA.cer")
        fmt.Println("You may alternatively load the .cer like this...")
        success = appleWwdrCert.LoadFromFile("qa_data/certs/AppleWWDRCA.cer")
        if success != true {
            fmt.Println(appleWwdrCert.LastErrorText())
            manifest.DisposeJsonObject()
            crypt.DisposeCrypt2()
            zip.DisposeZip()
            pngData.DisposeBinData()
            certVault.DisposeXmlCertVault()
            appleWwdrCert.DisposeCert()
            return
        }

    }

    certVault.AddCert(appleWwdrCert)
    crypt.UseCertVault(certVault)

    // Use a digital certificate and private key from a PFX
    bdPfx := chilkat.NewBinData()
    // Assume we loaded a PFX into bdPfx....
    pfxPassword := "test123"

    cert := chilkat.NewCert()
    success = cert.LoadPfxBd(bdPfx,pfxPassword)
    if success != true {
        fmt.Println(cert.LastErrorText())
        manifest.DisposeJsonObject()
        crypt.DisposeCrypt2()
        zip.DisposeZip()
        pngData.DisposeBinData()
        certVault.DisposeXmlCertVault()
        appleWwdrCert.DisposeCert()
        bdPfx.DisposeBinData()
        cert.DisposeCert()
        return
    }

    // Provide the signing cert (with associated private key).
    success = crypt.SetSigningCert(cert)
    if success != true {
        fmt.Println(crypt.LastErrorText())
        manifest.DisposeJsonObject()
        crypt.DisposeCrypt2()
        zip.DisposeZip()
        pngData.DisposeBinData()
        certVault.DisposeXmlCertVault()
        appleWwdrCert.DisposeCert()
        bdPfx.DisposeBinData()
        cert.DisposeCert()
        return
    }

    // Specify the signed attributes to be included.
    // (These attributes appear to not be necessary, but we're including
    // them just in case they become necessary in the future.)
    jsonSignedAttrs := chilkat.NewJsonObject()
    jsonSignedAttrs.UpdateInt("contentType",1)
    jsonSignedAttrs.UpdateInt("signingTime",1)
    crypt.SetSigningAttributes(jsonSignedAttrs.Emit())

    // Sign the manifest JSON to produce a signature
    crypt.SetEncodingMode("base64")
    sig := crypt.SignStringENC(*manifest.Emit())
    bdSig := chilkat.NewBinData()
    bdSig.AppendEncoded(*sig,"base64")
    entry = zip.AppendBd("signature",bdSig)
    entry.DisposeZipEntry()

    // ---------------------------------------------------------------------------------------------
    // Note: Chilkat also has the capability to do everything in-memory (no files would be involved).  
    // If this is of interest, please send email to support@chilkatsoft.com
    // ---------------------------------------------------------------------------------------------

    // Create the .pkipass archive (which is a .zip archive containing the required files).
    // the .zip is written to bdZip
    bdZip := chilkat.NewBinData()
    success = zip.WriteBd(bdZip)
    if success != true {
        fmt.Println(zip.LastErrorText())
        manifest.DisposeJsonObject()
        crypt.DisposeCrypt2()
        zip.DisposeZip()
        pngData.DisposeBinData()
        certVault.DisposeXmlCertVault()
        appleWwdrCert.DisposeCert()
        bdPfx.DisposeBinData()
        cert.DisposeCert()
        jsonSignedAttrs.DisposeJsonObject()
        bdSig.DisposeBinData()
        bdZip.DisposeBinData()
        return
    }

    fmt.Println("Success.")

    manifest.DisposeJsonObject()
    crypt.DisposeCrypt2()
    zip.DisposeZip()
    pngData.DisposeBinData()
    certVault.DisposeXmlCertVault()
    appleWwdrCert.DisposeCert()
    bdPfx.DisposeBinData()
    cert.DisposeCert()
    jsonSignedAttrs.DisposeJsonObject()
    bdSig.DisposeBinData()
    bdZip.DisposeBinData()