add download students list endpoint for coordinator view

backend/app/coordinator/routes/students.py

@@ -1,16 +1,18 @@
 from random import randint
 from itertools import islice
+from typing import List
 
-from flask import abort
+from flask import Response, abort
 from apiflask import APIBlueprint
 from sqlalchemy.exc import IntegrityError
 from flask_sqlalchemy import get_debug_queries
 
-from ...students.models import Student
+from ...students.models import Student, Group
+from ...project_supervisor.models import ProjectSupervisor
 from ..schemas import StudentSchema, StudentEditSchema, StudentsPaginationSchema, \
     StudentCreateSchema, MessageSchema, FileSchema, StudentQuerySchema
 from ...dependencies import db
-from ..utils import parse_csv
+from ..utils import parse_csv, generate_csv
 from ..exceptions import InvalidNameOrTypeHeaderException
 from ...base.utils import paginate_models, is_allowed_extensions
 
@@ -123,3 +125,14 @@ def upload_students(file: dict) -> dict:
         abort(400, "Invalid extension of file")
 
     return {"message": "Students was created by uploading csv file!"}
+
+
+@bp.route("/download/", methods=["POST"])
+def download_students() -> Response:
+    students = db.session.query(Student).join(Group).join(ProjectSupervisor).all()
+    if len(students) == 0:
+        abort(404, "Not found students, which are assigned to group!")
+    csv_file = generate_csv(students)
+    response = Response(csv_file, mimetype='text/csv')
+    response.headers.set("Content-Disposition", "attachment", filename="students_list.csv")
+    return response

backend/app/coordinator/utils.py

@@ -1,5 +1,5 @@
-from typing import Generator, Any
-from random import randint
+from typing import Generator, Any, List
+from collections import defaultdict
 
 import pandas as pd
 
@@ -28,15 +28,30 @@ def check_columns(df: pd.DataFrame) -> bool:
 def parse_csv(file, mode) -> Generator[Student, Any, None]:
     df = pd.read_csv(file)
 
-    # if not check_columns(df):
-    #     raise InvalidNameOrTypeHeaderException
+    if not check_columns(df):
+        raise InvalidNameOrTypeHeaderException
 
     students = (Student(last_name=dict(item.items())['NAZWISKO'],
                         first_name=dict(item.items())['IMIE'],
                         index=dict(item.items())['INDEKS'],
-                        pesel=str(int(dict(item.items())['PESEL'])) if not pd.isna(dict(item.items())['PESEL']) else None,
+                        pesel=str(int(dict(item.items())['PESEL'])) if not pd.isna(
+                            dict(item.items())['PESEL']) else None,
                         email=dict(item.items())['EMAIL'],
                         mode=mode)
                 for _, item in df.iterrows())
 
     return students
+
+
+def generate_csv(students: List[Student]) -> str:
+    headers = ['PESEL', 'INDEKS', 'IMIE', 'NAZWISKO', 'EMAIL', 'CDYD_KOD', 'PRZ_KOD', 'TZAJ_KOD', 'GR_NR', 'PRG_KOD']
+    data = [(student.pesel, student.index, student.first_name, student.last_name, student.email,
+             student.group.cdyd_kod, student.group.prz_kod, student.group.tzaj_kod, student.group.project_supervisor_id,
+             None) for student in students]
+    dataframe = defaultdict(list)
+    for row in data:
+        for idx, item in enumerate(row):
+            dataframe[headers[idx]].append(item)
+
+    df = pd.DataFrame(dataframe)
+    return df.to_csv(index=False)