public async Task <Course> GetCourseAsync(string courseTitle)
{
Guard.NotNullOrEmpty(courseTitle, nameof(courseTitle));
var filter = Builders <BsonDocument> .Filter
.Eq(Fields.CourseTitle, courseTitle);
var document = await _context.Courses
.Find(filter)
.SingleOrDefaultAsync();
if (document == null)
{
return(null);
}
return(new Course(
id: FromBson.GetId(document),
version: FromBson.GetVersion(document),
title: FromBson.GetCourseTitle(document),
teacher: FromBson.GetCourseTeacher(document),
capacity: FromBson.GetCourseCapacity(document)
));
}