andyfmiller

private void BuildLtiRequestViewBag(Assignment assignment)
{
    // Start with the basic and required parameters
    var parameters = BuildBaseLtiRequestData(assignment);

    // Add recommended and optional parameters
    AddOptionalParameters(assignment, parameters);

    // Add version specific parameters
    if (assignment.LtiVersionId == LtiVersion.Version10)

andyfmiller

        /// <summary>
        /// Add optional parameters that are specific to an LTI 1.1 request.
        /// </summary>
        /// <param name="assignment">The Assignment to be launched.</param>
        /// <param name="parameters">The partially filled OAuthParameters object
        /// that is being used to collect the data.</param>
        private void AddLti11Parameters(Assignment assignment, OAuthParameters parameters)
        {
            // LTI 1.1 does support custom parameter substitution
            if (!string.IsNullOrWhiteSpace(assignment.CustomParameters))

andyfmiller

        /// <summary>
        /// Add optional parameters that are specific to an LTI 1.0 request.
        /// </summary>
        /// <param name="assignment">The Assignment to be launched.</param>
        /// <param name="parameters">The partially filled OAuthParameters object
        /// that is being used to collect the data.</param>
        private void AddLti10Parameters(Assignment assignment, OAuthParameters parameters)
        {
            // LTI 1.0 does not include custom parameter substitution, so the custom parameter
            // values are added as-is.

andyfmiller

        /// <summary>
        /// Add the optional parameters for an LTI 1.x request.
        /// </summary>
        /// <param name="assignment">The Assignment to be launched.</param>
        /// <param name="parameters">The partially filled OAuthParameters object
        /// that is being used to collect the data.</param>
        private void AddOptionalParameters(Assignment assignment, OAuthParameters parameters)
        {
            var user = db.Users.Find(WebSecurity.CurrentUserId);

andyfmiller

        /// <summary>
        /// Calculate the data for a basic LTI 1.x request.
        /// </summary>
        /// <param name="assignment">The Assignment to be launched.</param>
        /// <returns>An OAuthParameters object which includes the required paremters
        /// for an LTI 1.x request.</returns>
        private OAuthParameters BuildBaseLtiRequestData(Assignment assignment)
        {
            const string lti_version = "LTI-1p0";
            const string lti_message_type = "basic-lti-launch-request";