public async Task <CourseSummaryDetailModel> Handle(CourseSummaryDetailQuery query, CancellationToken ct)
{
var filter = Builders <BsonDocument> .Filter
.Eq(Fields.CourseTitle, query.CourseTitle);
var project = Builders <BsonDocument> .Projection
.Include(Fields.CourseTitle)
.Include(Fields.CourseTeacher)
.Include(Fields.CourseCapacity)
.Include(Fields.CourseStudents)
.Include(Fields.CourseSummary);
var document = await _context.Courses
.Find(filter)
.Project(project)
.SingleOrDefaultAsync();
if (document == null)
{
return(null);
}
var studentsId = FromBson.GetCourseStudents(document)
.Select(id => ObjectId.Parse(id))
.ToList();
var studentsFilter = Builders <BsonDocument> .Filter
.In(Fields.Id, studentsId);
var studentsProject = Builders <BsonDocument> .Projection
.Include(Fields.StudentEmail)
.Include(Fields.StudentName);
var studentDocuments = await _context.Students
.Find(studentsFilter)
.Project(studentsProject)
.ToListAsync();
var students = studentDocuments.Select(studentDoc => {
return(new StudentSummaryModel {
Email = FromBson.GetStudentEmail(studentDoc),
Name = FromBson.GetStudentName(studentDoc)
});
})
.ToList();
var summaryDoc = FromBson.GetSummaryDocument(document);
return(new CourseSummaryDetailModel {
Title = FromBson.GetCourseTitle(document),
Teacher = document[Fields.CourseTeacher].ToString(),
Capacity = FromBson.GetCourseCapacity(document),
StudentCount = FromBson.GetSummaryStudentCount(summaryDoc),
MinAge = FromBson.GetSummaryMin(summaryDoc),
MaxAge = FromBson.GetSummaryMax(summaryDoc),
AverageAge = FromBson.GetSummaryAvg(summaryDoc),
Students = students
});
}
public async Task <Student> GetStudentAsync(string email)
{
Guard.NotNullOrEmpty(email, nameof(email));
var filter = Builders <BsonDocument> .Filter
.Eq(Fields.StudentEmail, email);
var document = await _context.Students
.Find(filter)
.SingleOrDefaultAsync();
if (document == null)
{
return(null);
}
return(new Student(
id: FromBson.GetId(document),
version: FromBson.GetVersion(document),
email: FromBson.GetStudentEmail(document),
name: FromBson.GetStudentName(document),
age: FromBson.GetStudentAge(document)
));
}