Class: DBSourceAdapter

Inherits:
Object
  • Object
show all
Defined in:
lib/repositories/adapters/db_source_adapter.rb

Instance Method Summary collapse

Constructor Details

#initialize ⇒ DBSourceAdapter

Returns a new instance of DBSourceAdapter.



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# File 'lib/repositories/adapters/db_source_adapter.rb', line 9

def initialize
  @db = DBDataSource.instance
end

Instance Method Details

#add_student(student) ⇒ Object 



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# File 'lib/repositories/adapters/db_source_adapter.rb', line 30

def add_student(student)
  template = 'INSERT INTO student(last_name, first_name, father_name, phone, telegram, email, git) VALUES (?, ?, ?, ?, ?, ?, ?)'
  @db.prepare_exec(template, *student_fields(student))
  @db.query('SELECT LAST_INSERT_ID()').first.first[1]
end

#paginated_short_students(page, count, existing_data_list = nil) ⇒ Object 



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# File 'lib/repositories/adapters/db_source_adapter.rb', line 20

def paginated_short_students(page, count, existing_data_list = nil)
  offset = (page - 1) * count
  students = @db.prepare_exec('SELECT * FROM student LIMIT ?, ?', offset, count)
  slice = students.map { |h| StudentShort.from_student(Student.from_hash(h)) }
  return DataListStudentShort.new(slice) if existing_data_list.nil?

  existing_data_list.replace_objects(slice)
  existing_data_list
end

#remove_student(student_id) ⇒ Object 



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# File 'lib/repositories/adapters/db_source_adapter.rb', line 41

def remove_student(student_id)
  @db.prepare_exec('DELETE FROM student WHERE id = ?', student_id)
end

#replace_student(student_id, student) ⇒ Object 



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# File 'lib/repositories/adapters/db_source_adapter.rb', line 36

def replace_student(student_id, student)
  template = 'UPDATE student SET last_name=?, first_name=?, father_name=?, phone=?, telegram=?, email=?, git=? WHERE id=?'
  @db.prepare_exec(template, *student_fields(student), student_id)
end

#student_by_id(student_id) ⇒ Object 



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# File 'lib/repositories/adapters/db_source_adapter.rb', line 13

def student_by_id(student_id)
  hash = @db.prepare_exec('SELECT * FROM student WHERE id = ?', student_id).first
  return nil if hash.nil?

  Student.from_hash(hash)
end

#student_count ⇒ Object 



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# File 'lib/repositories/adapters/db_source_adapter.rb', line 45

def student_count
  @db.query('SELECT COUNT(id) FROM student').first.first[1]
end