Assistant Role
- Access Rights
- Procedures

Assistant Role

Assistants have access to many procedures in the Exercise Management and Sheets section.

Parameter: Exercise Identifier

Access Rights

The assistant right grants access to the complete exercise tree with the corresponding id, from the Exercise Management and Sheets section.

Procedures

Exercise Management

changeAttributes(ident uid, ident id, string lecture, string term) {
  assume exists /account[uid]/admin || exists /account[uid]/assistant[id];
 
  assume exists /exercise[id]; # implicitly true in OO implementations
 
  update /exercise[id]/lecture lecture;
  update /exercise[id]/term term;
}

Sheet and Group Management

createSheet(ident uid, ident id, ident sheetId, double maxPoints) {
  assume exists /account[uid]/assistant[id];
 
  assume exists /exercise[id];
  assume not exists /exercise[id]/sheet[sheetId];
 
  assume maxPoints >= 0;
 
  insert /exercise[id] <sheet id=[sheetId] maxPoints=[maxPoints] />;
}

createGroup(ident uid, ident id, ident groupId, string day, string time, string location, integer maxSize) {
  assume exists /account[uid]/assistant[id];
 
  assume exists /exercise[id];
  assume not exists /exercise[id]/group[groupId];
 
  assume maxSize >= 0;
  assume day = "Monday" || day = "Tuesday" || ...;
 
  insert /exercise[id] <group id=[groupId] day=[day] time=[time] location=[location] curSize=[0] maxSize=[maxSize] />;
}

changeAttributes(ident uid, ident id, ident sheetId, double maxPoints) {
  assume exists /account[uid]/assistant[id];
 
  assume exists /exercise[id]/sheet[sheetId]; # implies the existence of the exercise
 
  assume maxPoints >= 0;
  assume /exercise[id]/student[x]/result[sheetId]/points <= maxPoints;
 
  update /exercise[id]/sheet[sheetId]/maxPoints maxPoints;
}

changeAttributes(ident uid, ident id, ident groupId, string day, string time, string location, integer maxSize) {
  assume exists /account[uid]/assistant[id];
 
  assume exists /exercise[id]/group[groupId]; # implicitly true in OO implementations
 
  assume maxSize >= 0;
  assume /exercise[id]/group[groupId]/curSize <= maxSize;
 
  update /exercise[id]/group[groupId]/day day;
  update /exercise[id]/group[groupId]/time time;
  update /exercise[id]/group[groupId]/location location;
  update /exercise[id]/group[groupId]/maxSize maxSize;
}

deleteSheet(ident uid, ident id, ident sheetId) {
  assume exists /account[uid]/assistant[id];
 
  assume exists /exercise[id]/sheet[sheetId]; # implies existence of the exercise
 
  assume size(/exercise[id]/student/result[sheetId]) = 0;
 
  remove /exercise[id]/sheet[sheetId];
}

deleteGroup(ident uid, ident id, ident groupId) {
  assume exists /account[uid]/assistant[id];
 
  assume exists /exercise[id]/group[groupId];
 
  assume size(/exercise[id]/group[groupId]/tutor) = 0;
  assume count(groupId, /exercise[id]/student/group)) = 0;
 
  remove /exercise[id]/group[groupId];
}

Tutor Management

grantTutorRights(ident uid, ident username, ident exerciseId, ident groupId) {
  assume exists /account[uid]/assistant[exerciseId];
 
  assume exists /account[username]; # implicitly true in OO implementations
  assume exists /exercise[exerciseId]/group[groupId];
 
  assume not exists /account[username]/tutor[exerciseId]/group[groupId]);
  assume not exists /exercise[exerciseId]/group[groupId]/tutor[username];
    # implied by integrity and the assumption before
 
  if not exists /account[username]/tutor[exerciseId] then # we could split the tutor rights here
    insert /account[username] <tutor exercise=[exerciseId] />;
  fi
  insert /account[username]/tutor[exerciseId] <group id=[groupId] />;
  insert /exercise[exerciseId]/group[groupId] <tutor account=[account] />;
}

revokeTutorRights(ident uid, ident username, ident exerciseId, ident groupId) {
  assume exists /account[uid]/assistant[exerciseId];
 
  assume exists /account[username]/tutor[exerciseId]/group[groupId];
  assume exists /exercise[exerciseId]/group[groupId]/tutor[username];
    # implied by integrity and the assumption before
 
  remove /account[username]/tutor[exerciseId]/group[groupId];
  if size(/account[username]/tutor[exerciseId]/group) = 0 then # should this be an additional procedure?
    remove /account[username]/tutor[exerciseId];
  fi
  remove /exercise[exerciseId]/group[groupId]/tutor[username];
}

Sign-Up Management

openSignUp(ident uid, ident id) {
  assume exists /account[uid]/assistant[id];
 
  assume exists /exercise[id];
 
  assume not /exercise[id]/open;
 
  update /exercise[id]/open true;
}

closeSignUp(ident uid, ident id) {
  assume exists /account[uid]/assistant[id];
 
  assume exists /exercise[id];
 
  assume /exercise[id]/open;
 
  update /exercise[id]/open false;
}

signUpGroup(ident uid, ident id, ident studentId, ident groupId) {
  assume exists /exercise[id] && /exercise[id]/open && 
         exists /account[uid]/student && /account[uid]/student/id = studentId
      || exists /account[uid]/assistant[id];
 
  assume exists /exercise[id]/student[studentId]; # implies the existence of the exercise
  assume exists /exercise[id]/group[groupId]; # also implies it, but once is really enough
 
  assume not exists /exercise[id]/student[studentId]/group;
  assume /exercise[id]/group[groupId]/curSize < /exercise[id]/group[groupId]/maxSize;
 
  insert /exercise[id]/student[studentId]/group groupId;
  update /exercise[id]/group[groupId]/curSize (/exercise[id]/group[groupId]/curSize + 1);
}

signOutGroup(ident uid, ident id, ident studentId) {
  assume exists /exercise[id] && /exercise[id]/open && 
         exists /account[uid]/student && /account[uid]/student/id = studentId
      || exists /account[uid]/assistant[id];
 
  assume exists /exercise[id]/student[studentId]/group;
    # implies existence of the exercise and student, even the group
 
 
  update /exercise[id]/group[/exercise[id]/student[studentId]/group]/curSize
    (/exercise[id]/group[/exercise[id]/student[studentId]/group]/curSize - 1)
  remove /exercise[id]/student[studentId]/group;
}

Student Management

signUpGroup(ident uid, ident id, ident studentId, ident groupId) {
  assume exists /exercise[id] && /exercise[id]/open && 
         exists /account[uid]/student && /account[uid]/student/id = studentId
      || exists /account[uid]/assistant[id];
 
  assume exists /exercise[id]/student[studentId]; # implies the existence of the exercise
  assume exists /exercise[id]/group[groupId]; # also implies it, but once is really enough
 
  assume not exists /exercise[id]/student[studentId]/group;
  assume /exercise[id]/group[groupId]/curSize < /exercise[id]/group[groupId]/maxSize;
 
  insert /exercise[id]/student[studentId]/group groupId;
  update /exercise[id]/group[groupId]/curSize (/exercise[id]/group[groupId]/curSize + 1);
}

signOutGroup(ident uid, ident id, ident studentId) {
  assume exists /exercise[id] && /exercise[id]/open && 
         exists /account[uid]/student && /account[uid]/student/id = studentId
      || exists /account[uid]/assistant[id];
 
  assume exists /exercise[id]/student[studentId]/group;
    # implies existence of the exercise and student, even the group
 
 
  update /exercise[id]/group[/exercise[id]/student[studentId]/group]/curSize
    (/exercise[id]/group[/exercise[id]/student[studentId]/group]/curSize - 1)
  remove /exercise[id]/student[studentId]/group;
}

addResult(ident uid, ident id, ident studentId, ident sheetId, double points) {
  assume exists /account[uid]/assistant[id] 
      || exists /account[uid]/tutor[id]/group[/exercise[id]/student[studentId]/group];
 
  assume exists /exercise[id]/student[studentId]; # implies the existence of the exercise
  assume exists /exercise[id]/sheet[sheetId]; # dito
 
  assume not exists /exercise[id]/student[studentId]/result[sheetId];
 
  assume points >= 0 && points <= /exercise[id]/sheet[sheetId]/maxPoints;
 
  insert /exercise[id]/student[studentId] <result sheet=[sheetId] points=[points] />;
}

changeResult(ident uid, ident id, ident studentId, ident sheetId, double points) {
  assume exists /account[uid]/assistant[id]
      || exists /account[uid]/tutor[id]/group[/exercise[id]/student[studentId]/group];
 
  assume exists /exercise[id]/student[studentId]; # implies the existence of the exercise
  assume exists /exercise[id]/sheet[sheetId]; # dito
 
  assume points >= 0 && points <= /exercise[id]/sheet[sheetId]/maxPoints;
 
  assume exists /exercise[id]/student[studentId]/result[sheetId];
 
  update /exercise[id]/student[studentId]/result[sheetId]/points points;
}

removeResult(ident uid, ident id, ident studentId, ident sheetId) {
  assume exists /account[uid]/assistant[id]
      || exists /account[uid]/tutor[id]/group[/exercise[id]/student[studentId]/group];
 
  assume exists /exercise[id]/student[studentId]/result[sheetId]; # implies the existence of pretty much everything
 
  remove /exercise[id]/student[studentId]/result[sheetId];
}

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