c# samples of youtube API (or gdata API) using OpenID and OAuth

Question

Are there any c# code samples of youtube API (or gdata API) using OpenID and OAuth ?

Or maybe a post / article with code examples

Code samples of using dotnetoauth with the youtube API would be great too

Answer 1

Having just spent the last 2 weeks getting an Oauth connection to YouTube to get an authorization to access playlists, I can send you a load of classes that will help. I can post sections here, but theres more than It will let me post!

While I can now gain access to private feeds, I cant get the upload of videos to work using OAuth. The google docs say it works, but the last actual posted SDK was Feb last year. You can download the source code and compile it, but I still had problems and built my own classes. I have ended up resorting to ClientLogin for the uploads of video, but OAuth for everything else...

Drop me a note with your email address and what you are trying to acheive and i'll send you the classes i've now written.

Heres some code: First A class that does the OAuth Signing and some other stuff like header creation:

#Region "Imports"
Imports System.Text
Imports System.Security.Cryptography
#End Region

Public NotInheritable Class SharedOAuth

#Region "Class Declarations"
    Private Const unreservedChars As String = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_.~"

    Private Const OAuthVersion As String = "1.0"
    Private Const OAuthParameterPrefix As String = "oauth_"
    Private Const OAuthParameterExclusionPrefix As String = "xoauth_"

    Private Const OAuthConsumerKeyKey As String = "oauth_consumer_key"
    Private Const OAuthCallbackKey As String = "oauth_callback"
    Private Const OAuthVersionKey As String = "oauth_version"
    Private Const OAuthSignatureMethodKey As String = "oauth_signature_method"
    Private Const OAuthSignatureKey As String = "oauth_signature"
    Private Const OAuthTimestampKey As String = "oauth_timestamp"
    Private Const OAuthNonceKey As String = "oauth_nonce"
    Private Const OAuthTokenKey As String = "oauth_token"
    Private Const OAuthTokenSecretKey As String = "oauth_token_secret"
#End Region

#Region "Constructor"
    Private Sub New()
        'prevent construction
    End Sub
#End Region


#Region "Shared Functions"
    Public Shared Function GetSignatureTypeNameFromType(ByVal signatureType As enumerations.OAuthEnumerations.SignatureTypes) As String
        Select Case signatureType
            Case enumerations.OAuthEnumerations.SignatureTypes.HmacSha1
                Return "HMAC-SHA1"
            Case Else
                Return String.Empty
        End Select
    End Function

    Public Shared Function GenerateTimeStamp() As String
        'Implementation of UNIX current UTC time
        Dim _ts As TimeSpan = DateTime.UtcNow - New DateTime(1970, 1, 1, 0, 0, 0, 0)
        Return Convert.ToInt64(_ts.TotalSeconds).ToString(CultureInfo.InvariantCulture)
    End Function

    Public Shared Function GenerateNonce() As String
        'Some random Number
        Return New Random().Next(123400, 9999999).ToString
    End Function

    Public Shared Function UrlEncode(ByVal value As String) As String
        Dim _result As New StringBuilder

        If (String.IsNullOrEmpty(value)) Then
            Return value
        End If

        For Each _symbol As Char In value
            If unreservedChars.IndexOf(_symbol) <> -1 Then
                _result.Append(_symbol)
            Else
                _result.Append(String.Format("%{0}", String.Format("{0:X2}", Asc(_symbol))))
            End If
        Next

        Return _result.ToString
    End Function

    ''' <summary>
    '''Generates a signature using the specified signatureType 
    '''    </summary>       
    '''    <param name="url">The full url that needs to be signed including its non OAuth url parameters</param>
    '''    <param name="consumerKey">The consumer key</param>
    '''    <param name="consumerSecret">The consumer seceret</param>
    '''    <param name="token">The token, if available. If not available pass null or an empty string</param>
    '''    <param name="tokenSecret">The token secret, if available. If not available pass null or an empty string</param>
    '''    <param name="httpMethod">The http method used. Must be a valid HTTP method verb (POST,GET,PUT, etc)</param>
    '''   <param name="signatureType">The type of signature to use</param>
    '''   <returns>A base64 string of the hash value</returns>
    Public Shared Function GenerateSignature(ByVal url As Uri, ByVal consumerKey As String, ByVal consumerSecret As String, ByVal token As String, ByVal tokenSecret As String, ByVal httpMethod As String, ByVal timeStamp As String, ByVal nonce As String, ByVal signatureType As enumerations.OAuthEnumerations.SignatureTypes, ByRef normalizedUrl As String, ByRef normalizedRequestParameters As String) As String
        normalizedUrl = String.Empty
        normalizedRequestParameters = String.Empty

        Dim _signatureBase As String
        Dim _hash As HMACSHA1

        Select Case signatureType
            Case enumerations.OAuthEnumerations.SignatureTypes.HmacSha1
                _signatureBase = GenerateSignatureBase(url, consumerKey, token, tokenSecret, httpMethod, timeStamp, nonce, enumerations.OAuthEnumerations.SignatureTypes.HmacSha1, normalizedUrl, normalizedRequestParameters)

                Dim _sb As New StringBuilder
                With _sb
                    .Append(UrlEncode(consumerSecret))
                    .Append("&")

                    If (String.IsNullOrEmpty(tokenSecret)) Then
                        .Append("")
                    Else
                        .Append(UrlEncode(tokenSecret))
                    End If
                End With

                _hash = New HMACSHA1
                _hash.Key = Encoding.ASCII.GetBytes(_sb.ToString)

                Return GenerateSignatureUsingHash(_signatureBase, _hash)

            Case Else
                Throw New NotImplementedException

        End Select
    End Function

    Public Shared Function GenerateSignatureUsingHash(ByVal signatureBase As String, ByVal hash As HashAlgorithm) As String
        Return ComputeHash(hash, signatureBase)
    End Function

    Public Shared Function GenerateSignatureBase(ByVal url As Uri, ByVal consumerKey As String, ByVal token As String, ByVal tokenSecret As String, ByVal httpMethod As String, ByVal timeStamp As String, ByVal nonce As String, ByVal signatureType As enumerations.OAuthEnumerations.SignatureTypes, ByRef normalizedUrl As String, ByRef normalizedRequestParameters As String) As String
        Dim _SignatureTypeName As String = GetSignatureTypeNameFromType(signatureType)

        If String.IsNullOrEmpty(token) Then
            token = String.Empty
        End If

        If String.IsNullOrEmpty(tokenSecret) Then
            tokenSecret = String.Empty
        End If

        If String.IsNullOrEmpty(consumerKey) Then
            Throw New ArgumentNullException("consumerKey")
        End If

        If String.IsNullOrEmpty(httpMethod) Then
            Throw New ArgumentNullException("httpMethod")
        End If

        If String.IsNullOrEmpty(_SignatureTypeName) Then
            Throw New ArgumentNullException("SignatureType")
        End If

        normalizedUrl = String.Empty
        normalizedRequestParameters = String.Empty

        Dim _params As List(Of QueryParameter) = getqueryparameters(url.Query)

        With _params
            .Add(New QueryParameter(OAuthVersionKey, OAuthVersion))
            .Add(New QueryParameter(OAuthNonceKey, nonce))
            .Add(New QueryParameter(OAuthTimestampKey, timeStamp))
            .Add(New QueryParameter(OAuthSignatureMethodKey, _SignatureTypeName))
            .Add(New QueryParameter(OAuthConsumerKeyKey, consumerKey))

            If Not (String.IsNullOrEmpty(token)) Then
                .Add(New QueryParameter(OAuthTokenKey, token))
            End If

            .Sort(New QueryParameterComparer)
        End With

        normalizedUrl = String.Format("{0}://{1}", url.Scheme, url.Host)

        If Not ((url.Scheme = "http" AndAlso url.Port = 80) OrElse (url.Scheme = "https" AndAlso url.Port = 443)) Then
            normalizedUrl = String.Format("{0}:{1}", normalizedUrl, url.Port)
        End If

        normalizedUrl = String.Format("{0}{1}", normalizedUrl, url.AbsolutePath)

        normalizedRequestParameters = NormalizeRequestParameters(_params)

        Dim _sb As New StringBuilder
        With _sb
            .AppendFormat(CultureInfo.InvariantCulture, "{0}&", httpMethod.ToUpper)
            .AppendFormat(CultureInfo.InvariantCulture, "{0}&", UrlEncode(normalizedUrl))
            .AppendFormat(CultureInfo.InvariantCulture, "{0}", UrlEncode(normalizedRequestParameters))
        End With

        Return _sb.ToString

    End Function
#End Region

#Region "Private Methods"
    Private Shared Function ComputeHash(ByVal hashAlgorithm As HashAlgorithm, ByVal data As String) As String
        If hashAlgorithm Is Nothing Then
            Throw New ArgumentNullException("hashAlgorithm")
        End If

        If String.IsNullOrEmpty(data) Then
            Throw New ArgumentNullException("data")
        End If

        Dim _dataBuffer As Byte() = Encoding.ASCII.GetBytes(data)
        Dim _hashBytes As Byte() = hashAlgorithm.ComputeHash(_dataBuffer)

        Return Convert.ToBase64String(_hashBytes)
    End Function


    Private Shared Function NormalizeRequestParameters(ByVal parameters As IList(Of QueryParameter)) As String

        Dim _p As QueryParameter
        Dim _sb As New StringBuilder

        For i As Integer = 0 To parameters.count - 1
            _p = parameters(i)
            _sb.AppendFormat(CultureInfo.InvariantCulture, "{0}={1}", _p.Name, _p.Value)

            If i < parameters.count - 1 Then
                _sb.Append("&")
            End If
        Next

        Return _sb.ToString

    End Function

    Private Shared Function GetQueryParameters(ByVal parameters As String) As List(Of QueryParameter)
        If (parameters.StartsWith("?")) Then
            parameters = parameters.Remove(0, 1)
        End If

        Dim _result As New List(Of QueryParameter)
        Dim _p As String() = parameters.Split("&"c)

        Dim _temp As String()

        If Not (String.IsNullOrEmpty(parameters)) Then

            For Each s As String In _p
                If Not (String.IsNullOrEmpty(s)) AndAlso Not (s.StartsWith(OAuthParameterExclusionPrefix)) Then 'AndAlso (s.StartsWith(OAuthParameterPrefix)) Then
                    If s.IndexOf("=") > -1 Then
                        _temp = s.Split("="c)
                        _result.Add(New QueryParameter(_temp(0), _temp(1)))
                    Else
                        _result.Add(New QueryParameter(s, String.Empty))
                    End If
                End If

            Next

        End If

        Return _result

    End Function
#End Region


End Class

Then, I consume this is a wrapper class to help making the calls easier:

  Public Function SignCommandUrl(ByVal commandUrl As String) As String
        Return SignCommandUrl(commandUrl, Nothing, Nothing)
    End Function

    Public Function SignCommandUrl(ByVal commandUrl As String, ByVal overrideToken As String, ByVal overrideTokenSecret As String) As String
        Dim _commandUri = New Uri(commandUrl)
        Dim _oAuthSignature As String
        Dim _oAuthTimeStamp As String = SharedOAuth.GenerateTimeStamp
        Dim _oAuthNOnce As String = SharedOAuth.GenerateNonce
        Dim _oAuth_normalized_url As String = String.Empty
        Dim _oAuth_normalized_params As String = String.Empty

        If Not (String.IsNullOrEmpty(overrideToken)) OrElse Not (String.IsNullOrEmpty(overrideTokenSecret)) Then
            _oAuthSignature = SharedOAuth.GenerateSignature(_commandUri, CONSUMER_KEY, CONSUMER_SECRET, overrideToken, overrideTokenSecret, "GET", _oAuthTimeStamp, _oAuthNOnce, enumerations.OAuthEnumerations.SignatureTypes.HmacSha1, _oAuth_normalized_url, _oAuth_normalized_params)
        Else

            If MasterAccessToken Is Nothing Then
                _oAuthSignature = SharedOAuth.GenerateSignature(_commandUri, CONSUMER_KEY, CONSUMER_SECRET, String.Empty, String.Empty, "GET", _oAuthTimeStamp, _oAuthNOnce, enumerations.OAuthEnumerations.SignatureTypes.HmacSha1, _oAuth_normalized_url, _oAuth_normalized_params)
            Else
                _oAuthSignature = SharedOAuth.GenerateSignature(_commandUri, CONSUMER_KEY, CONSUMER_SECRET, SharedOAuth.UrlEncode(MasterAccessToken.Token), MasterAccessToken.TokenSecret, "GET", _oAuthTimeStamp, _oAuthNOnce, enumerations.OAuthEnumerations.SignatureTypes.HmacSha1, _oAuth_normalized_url, _oAuth_normalized_params)
            End If
        End If

        'Get a token
        Dim _sb As New System.Text.StringBuilder
        With _sb
            .Append(_oAuth_normalized_url)
            .Append("?")
            .Append(_oAuth_normalized_params)
            .Append("&")
            .Append("oauth_signature")
            .Append("=")
            .Append(SharedOAuth.UrlEncode(_oAuthSignature))
        End With

        Return _sb.ToString
    End Function

    Public Function BuildPostHeader(ByVal commandUrl As String) As String
        Dim _commandUri = New Uri(commandUrl)
        Dim _oAuthTimeStamp As String = SharedOAuth.GenerateTimeStamp
        Dim _oAuthNOnce As String = SharedOAuth.GenerateNonce
        Dim _oAuth_normalized_url As String = String.Empty
        Dim _oAuth_normalized_params As String = String.Empty
        Dim _oAuthSignature As String

        If MasterAccessToken Is Nothing Then
            _oAuthSignature = SharedOAuth.GenerateSignature(_commandUri, CONSUMER_KEY, CONSUMER_SECRET, String.Empty, String.Empty, "POST", _oAuthTimeStamp, _oAuthNOnce, enumerations.OAuthEnumerations.SignatureTypes.HmacSha1, _oAuth_normalized_url, _oAuth_normalized_params)
        Else
            _oAuthSignature = SharedOAuth.GenerateSignature(_commandUri, CONSUMER_KEY, CONSUMER_SECRET, SharedOAuth.UrlEncode(MasterAccessToken.Token), MasterAccessToken.TokenSecret, "POST", _oAuthTimeStamp, _oAuthNOnce, enumerations.OAuthEnumerations.SignatureTypes.HmacSha1, _oAuth_normalized_url, _oAuth_normalized_params)
        End If


        Dim _sb As New System.Text.StringBuilder
        With _sb
            .Append("Authorization: OAuth oauth_version=""1.0"", ")
            .AppendFormat("oauth_nonce=""{0}"", ", _oAuthNOnce)
            .AppendFormat("oauth_timestamp=""{0}"", ", _oAuthTimeStamp)
            .AppendFormat("oauth_consumer_key=""{0}"", ", CONSUMER_KEY)
            .AppendFormat("oauth_token=""{0}"", ", MasterAccessToken.Token)
            .Append("oauth_signature_method=""HMAC-SHA1"", ")
            .AppendFormat("oauth_signature=""{0}""", _oAuthSignature)
        End With

        Return _sb.ToString
    End Function

    Public Shared Function PostRequestReturnCollection(ByVal commandUrl As String) As NameValueCollection
        Dim _nameValCollection As NameValueCollection

        Dim _request As HttpWebRequest = CType(WebRequest.Create(commandUrl), HttpWebRequest)

        Using _response As HttpWebResponse = CType(_request.GetResponse, HttpWebResponse)
            Using _reader As TextReader = New StreamReader(_response.GetResponseStream)
                _nameValCollection = HttpUtility.ParseQueryString(_reader.ReadToEnd)
            End Using
        End Using

        Return _nameValCollection
    End Function