web_services: callback: define VMCHECKER_HOME in apache conf

If HOME variable is not defined (which can happen depending on the setup)
then the callback functions will fail because the search path for the key is
relative to this variable.

Signed-off-by: Lucian Cojocar <cojocar@gmail.com>

web_services/services.py

@@ -39,6 +39,9 @@
 ERR_OTHER = 3
 
 
+def __fixup_env(req):
+    if 'HOME' not in os.environ:
+        os.environ['HOME'] = req.get_options()["VMCHECKER_HOME"]
 
 ########## @ServiceMethod
 def uploadedFile(req, courseId, assignmentId, tmpname):
@@ -73,6 +76,7 @@ def uploadedFile(req, courseId, assignmentId, tmpname):
     strout = websutil.OutputString()
     sys.stdout = strout
     try:
+        __fixup_env(req)
         submit.submit(tmpname, assignmentId, username, courseId)
         update_db.update_grades(courseId, user=username, assignment=assignmentId)
     except submit.SubmittedTooSoonError:
@@ -136,6 +140,7 @@ def uploadAssignment(req, courseId, assignmentId, archiveFile):
     strout = websutil.OutputString()
     sys.stdout = strout
     try:
+        __fixup_env(req)
         submit.submit(tmpname, assignmentId, username, courseId)
         update_db.update_grades(courseId, user=username, assignment=assignmentId)
     except submit.SubmittedTooSoonError:
@@ -192,6 +197,7 @@ def uploadAssignmentMd5(req, courseId, assignmentId, md5Sum):
     strout = websutil.OutputString()
     sys.stdout = strout
     try:
+        __fixup_env(req)
         submit.submit(tmpname, assignmentId, username, courseId)
         update_db.update_grades(courseId, user=username, assignment=assignmentId)
     except submit.SubmittedTooSoonError:
@@ -249,6 +255,7 @@ def beginEvaluation(req, courseId, assignmentId, archiveFileName):
     sys.stdout = strout
 
     try:
+        __fixup_env(req)
         submit.evaluate_large_submission(archiveFileName, assignmentId, username, courseId)
     except submit.SubmittedTooSoonError:
         traceback.print_exc(file = strout)