system-pri/backend/app/students/routes/registrations.py

from apiflask import APIBlueprint

from ...base.utils import paginate_models
from ...dependencies import db
from ...project_supervisor.models import ProjectSupervisor
from ..models import Group
from ..schemas import ProjectSupervisorPaginationSchema, ProjectSupervisorQuerySchema

bp = APIBlueprint("registrations", __name__, url_prefix="/registrations")


@bp.get("/<int:year_group_id>/")
@bp.input(ProjectSupervisorQuerySchema, location="query")
@bp.output(ProjectSupervisorPaginationSchema)
def list_available_groups(year_group_id: int, query: dict) -> dict:
    page = query.get("page")
    per_page = query.get("per_page")

    available_groups = ProjectSupervisor.limit_group - db.func.count(Group.id)
    ps_query = (
        db.session.query(ProjectSupervisor, available_groups)
        .join(Group, isouter=True)
        .filter(ProjectSupervisor.year_group_id == year_group_id)
        .group_by(ProjectSupervisor.id)
    )

    data = paginate_models(page, ps_query, per_page)

    project_supervisors = []
    for project_supervisor, available_groups in data["items"]:
        setattr(project_supervisor, "available_groups", available_groups)
        project_supervisors.append(project_supervisor)

    return {"project_supervisors": project_supervisors, "max_pages": data["max_pages"]}