Don't try to send file unless latex succeeded

TODO: Report latex errors to the user

latty.py

@@ -3,14 +3,9 @@
 import os
 import subprocess
 from dataclasses import dataclass
-
 from flask import send_from_directory
 
 
-# latex /home/sage/Documents/latex/coverLetter/temp.tex'
-# dvipdf /home/sage/Documents/latex/coverLetter/temp.dvi ~/Documents/SageVaillancourt_CoverLetter.pdf'
-# rm -r /home/sage/Documents/latex/coverLetter/temp*'
-
 @dataclass
 class CLData():
     username: str
@@ -53,19 +48,21 @@ def generate(data: CLData, unique):
     base_tex = output_dir + unique + ".tex"
     com = "pdflatex -halt-on-error -jobname=outputs/" + unique + " " + base_tex
     print("COM: '" + com + "'")
-    #TODO: If error, don't try to return the pdf
-    subprocess.run(['bash', '-c', com])
+    try:
+        subprocess.check_call(['bash', '-c', com])
 
-    root_dir = os.path.dirname(os.getcwd())
-    download = root_dir + '/undercover/outputs/'
+        root_dir = os.path.dirname(os.getcwd())
+        download = root_dir + '/undercover/outputs/'
 
-    threading.Timer(60 * 30, cleanup, [output_dir + unique]).start()
-    return send_from_directory(
-        download,
-        unique + ".pdf",
-        attachment_filename=data.username.replace(" ", "") + "_CoverLetter.pdf",
-        as_attachment=True
-    )
+        threading.Timer(60 * 30, cleanup, [output_dir + unique]).start()
+        return send_from_directory(
+            download,
+            unique + ".pdf",
+            attachment_filename=data.username.replace(" ", "") + "_CoverLetter.pdf",
+            as_attachment=True
+        )
+    except subprocess.CalledProcessError:
+        return None
 
 def cleanup(unique):
     print(unique)

writing.py

@@ -1,6 +1,6 @@
 # Copyright Sage Vaillancourt 2021
 
-from flask import (Blueprint, render_template, request)
+from flask import (Blueprint, render_template, request, make_response)
 from wtforms import Form, BooleanField, StringField, TextAreaField, validators
 
 from latty import (CLData, generate)
@@ -69,6 +69,11 @@ def index():
 
         resp = generate(data, get_unique())
         # Save entered data as cookies on user's machine
+        if not resp:
+            resp = make_response(render_template('writing.html',
+                form=form,
+                unique=get_unique(),
+            ))
         for pair in data.get_pairs():
             resp.set_cookie(pair[0], urllib.parse.quote(pair[1]))
         return resp