Bunch of fixes for code submission backend

src/problems/migrations/0009_user_timestamped_filepaths.py

@@ -0,0 +1,19 @@
+# Generated by Django 3.1.6 on 2021-03-28 18:26
+
+from django.db import migrations, models
+import problems.models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('problems', '0008_problem_subfields'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='submission',
+            name='file',
+            field=models.FileField(upload_to=problems.models.user_timestamped_filepath, verbose_name='source code file'),
+        ),
+    ]

src/problems/models.py

@@ -1,3 +1,6 @@
+import os
+import datetime
+
 from datetime import date
 
 from django.db import models
@@ -58,6 +61,19 @@ def __str__(self):
 
     visible = models.BooleanField(default=False)
 
+# This is used to determine media filepaths for code files submitted via the "submit file" button.
+def user_timestamped_filepath(instance, filename):
+    datetime_now = datetime.datetime.now()
+    year = datetime_now.strftime("%Y")
+    month = datetime_now.strftime("%m")
+    day = datetime_now.strftime("%d")
+
+    base_filename, extension = os.path.splitext(filename)
+    username = instance.user.user.username
+    timestamp = datetime_now.strftime("%Y%m%d%H%M%S")
+    user_timestamped_filename = f"{base_filename}_{username}_{timestamp}{extension}"
+
+    return f"uploads/{year}/{month}/{day}/{user_timestamped_filename}"
 
 class Submission(models.Model):
     id = models.AutoField(primary_key=True)
@@ -68,7 +84,7 @@ class Submission(models.Model):
     passed = models.BooleanField()
     date = models.DateTimeField(auto_now_add=True, verbose_name='submission date')
     language = models.CharField(max_length=256, verbose_name='programming language')
-    file = models.FileField(upload_to='uploads/%Y/%m/%d', verbose_name='source code file')
+    file = models.FileField(upload_to=user_timestamped_filepath, verbose_name='source code file')
     runtime_sum = models.FloatField(default=0.0)
     max_mem_usage = models.FloatField(default=0.0)
 

src/problems/views.py

@@ -145,30 +145,45 @@ def post(request, problem_name):
         logger.info("Submission from user: {}".format(user))
         logger.info("Submission from user_profile: {}".format(user_profile))
 
-        language = request.POST['language']
-        extension = {'python': 'py', 'javascript': 'js', 'julia': 'jl'}.get(language)
-        logger.info("Language selected: {:s}".format(language))
-
         if button_clicked == 'submit-code-button':
+            language = request.POST['language']
+            logger.info("Language selected: {:s}".format(language))
+
+            extension = {'python': 'py', 'javascript': 'js', 'julia': 'jl', 'c': 'c'}.get(language)
+
             editor_code = request.POST['raw-code']
             logger.info("User code:\n{:}".format(editor_code))
             raw_code = str(base64.b64encode(bytes(editor_code, 'utf-8')), 'utf-8')
 
-            t = datetime.datetime.now()
-            user_code_filename = "{:}_{:}_{:}.{}".format(problem_name, username, t.strftime("%Y%m%d%H%M%S"), extension)
-            user_code_filepath = os.path.join(settings.MEDIA_ROOT, "uploads", str(t.year), str(t.month), str(t.day), user_code_filename)
+            datetime_now = datetime.datetime.now()
+            year = datetime_now.strftime("%Y")
+            month = datetime_now.strftime("%m")
+            day = datetime_now.strftime("%d")
+            timestamp = datetime_now.strftime("%Y%m%d%H%M%S")
+
+            user_code_filename = f"{problem_name}_{username}_{timestamp}.{extension}"
+            user_code_filepath = os.path.join(settings.MEDIA_ROOT, "uploads", year, month, day, user_code_filename)
 
             user_code_dir = os.path.dirname(user_code_filepath)
             if not os.path.exists(user_code_dir):
-                logger.info("Creating directory: {:}".format(user_code_dir))
+                logger.info(f"Creating directory: {user_code_dir}")
                 os.makedirs(user_code_dir)
 
-            logger.info("Writing user code to file: {:s}".format(user_code_filepath))
-            pfile = open(user_code_filepath, 'w+')  # Python file
-            file = File(pfile)  # Creating Django file from Python file
-            file.name = os.path.join("uploads", str(t.year), str(t.month), str(t.day), user_code_filename)
+            logger.info(f"Writing user code to file: {user_code_filepath}")
+
+            # Not sure if there's a simpler way to do this but we first create a Python File
+            # and write the code into it. We then create a Django File from the Python File
+            # so we can pass it to Django when creating the `Submission` below.
+            # We then delete the Python File at the end lol.
+
+            pfile = open(user_code_filepath, 'w+')  # Python File
             pfile.write(editor_code)
-            # We close pfile at the end, after the submission has been saved.
+
+            file = File(pfile)  # Creating Django File from Python file
+
+            # Apparently this will use the user_timestamped_filepath function to determine the filepath
+            # so we give it a generic filename like "chaos.py" and Django figures out the rest.
+            file.name = problem_name + "." + extension
 
             logger.debug("user_code_filepath = {}".format(user_code_filepath))
             logger.debug("user_code_filename = {}".format(user_code_filename))
@@ -179,10 +194,18 @@ def post(request, problem_name):
             try:
                 file = form.files['file']
             except KeyError:
-                return JsonResponse({'error': 'Please attach your file before submitting.'})
+                return JsonResponse({'error': 'Please choose and attach your file before submitting.'})
 
             if file.size > MAX_FILE_SIZE_BYTES:
-                return JsonResponse({'error': 'File must be smaller than {} bytes.'.format(MAX_FILE_SIZE_BYTES)})
+                return JsonResponse({'error': f'File must be smaller than {MAX_FILE_SIZE_BYTES} bytes.'})
+
+            base_filename, extension = os.path.splitext(file.name)
+            ext2language = {'.py': 'python', '.js': 'javascript', '.jl': 'julia', '.c': 'c'}
+            language = ext2language.get(extension)
+
+            if language is None:
+                supported_extensions = "".join([lang + " -> " + ext + "\n" for ext, lang in ext2language.items()])
+                return JsonResponse({'error': f'Invalid file extension: {extension}. Supported languages and extensions are\n' + supported_extensions})
 
             raw_code = str(base64.b64encode(file.read()), 'utf-8')
 
@@ -236,19 +259,20 @@ def post(request, problem_name):
         )
         submission.save()
 
+        if button_clicked == "submit-code-button":
+            pfile.close()
+            os.remove(pfile.name)
+
         # Increment user's submission count by 1.
-        # user_profile.update(submissions_made=F('submissions_made') + 1)
         UserProfile.objects.filter(user=user).update(submissions_made=F('submissions_made') + 1)  # this can be simplified
-        # If successful and is user's first successful submission, increment problem's solved_by and user's problems_solved.
+
+        # If successful and is user's first successful submission, increment problem's solved_by by 1 and user's problems_solved by 1.
         if results['success']:
             num_previous_successful_submissions = Submission.objects.filter(user=user_profile, passed=True, problem__name=problem_name).count()
             logger.info("# previous successful submissions: {:}".format(num_previous_successful_submissions))
             if num_previous_successful_submissions == 1:
-                logger.info("User {:} successfully solved {:}. Incrementing problem's solved_by 1 to TODO.".format(user_profile, problem_name))
+                logger.info("User {:} successfully solved {:}. Incrementing problem's solved_by 1.".format(user_profile, problem_name))
                 Problem.objects.filter(name=problem_name).update(solved_by=F('solved_by') + 1)
                 UserProfile.objects.filter(user=user).update(problems_solved=F('problems_solved') + 1)  # this can be simplified
 
-        if button_clicked == "submit-code-button":
-            pfile.close()
-
         return JsonResponse({'results': results})