vmchecker user guide
This is a guide for teaching assistants using vmchecker. For information about vmchecker structure, sources and contributing guidelines check HACKING.rst
Course directory structure
The files in each course's vmchecker-storer directory:
auth_file.json- custom accounts for students who cannot use LDAP for authentication
- entries are of the form
"username" : "password"
- after editing this file check that authentication still works as JSON formatting errors may block the login for all students
- entries are of the form
config- course configuration file (see bellow)
gitrepository of all students assignments
- Structure: repo/
archive.zip- the student's last submission for this assignment
archive- unzipped version of this submission. The contents of this directory are stored in the
gitrepository. You can use
gitto see previous versions of the student's submissions for this assignment.
results- this is only present if the submission was tested.
build-stderr.vmr- output of the submission's and test compilation
run-stderr.vmr- output from running the tests
run-km.vmr- kernel messages (dmesg, dbgview)
vmchecker-stderr.vmr- vmchecker internal errors
To grade a homework you must edit repo/
Penalties for exceeding the deadline will be automatically computed based on the submission's upload time, the assignment's deadline (official holidays are not counted as penalties).
For an unmarked submission, the grade.vmr file contains only one word: "
vmchecker reads all lines from grade.vmr and interprets only the first word on the line. If the word is a number (convertible to
float in Python) than that number is added to the total grade (
10 for a perfect submission).
Examples (considering the submission sent before the deadline):
+1.0 nice algorithm -0.2: ugly intendation It's almost unreadable! -0.1: inconsitent naming 0.1: nice README graded by: Lucian Adrian Grijincu
The previous example is graded at
10 + 1.0 - 0.2 - 0.1 = 10.7. The grade is not bounded by
10 because some assignments may have bonuses.
The spacing before the first number on the line is ignored. After the number you may only put whitespace or '
:'. Anything else and the number is treated as a string and not added to the grade.
As lines that do not begin with a number are ignored by the grading tools, but displayed to the student, you can use this file to comment and argument the penalty/bonuses given. Writing your name in the file will tell the student who to contact if he has any remarks regarding the grading.
vmchecker will DELETE results and
grade.vmr when the student send another submission for that assignment.
vmchecker does not prevent a student from uploading a homework again after it was graded!
Add a new assignment
An example assignment specification:
[assignment minishell-windows] Deadline = 2010.03.31 23:59:00 Machine = so-win Timeout=150 AssignmentTitle = Minishell (Windows) StatementLink = http://elf.cs.pub.ro/so/wiki/teme/tema-1 OrderNumber = 2
The string after
assignment is the ID of the assignment. This may NOT contain spaces!
Deadline- the date after which students are penalized for late submissions
Machine- the ID of the virtual machine used to test this assignment
Timeoutis the ammount of time (in seconds) after which testing is aborted.
AssignmentTitle- a human readable name for the assignment
StatementLink- a link to a resource (pdf, html, etc.) describing the assignment
OrderNumberis used to order assignments when presented to the student. These should be numbers starting from
1for the first assignment and incremented for each new one.
Assignment test archives must be placed in tests/
Resubmit an assignment
In order to resubmit a student upload for rechecking you must:
- delete the results folder from the current upload, e.g.
rm -rf vmchecker-storer/repo/assign1/student.name/current/results
vmchecker-resubmit -c <course-id> -u <student-name> -a <assignment-name>
vmchecker-resubmit also has an
--all option if you want to mass resubmit.
Add a new instance
To create an instance for a new school year, based of the previous year:
- create a new folder
- inside the folder run
config, build/run scripts and tests from previous year
vmchecker-storersymbolic link to new instance folder