From 64ad30d9100194522d35a77acc8784da44f10020 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Thu, 17 Jan 2019 09:25:55 +0530
Subject: [PATCH] Content server: Fix a regression in the previous release that
 broke viewing math ebooks in the browser viewer. Fixes #1810884 [recent
 changes to mathjax broke
 server](https://bugs.launchpad.net/calibre/+bug/1810884)

---
 src/calibre/srv/books.py         | 4 ++--
 src/calibre/utils/rapydscript.py | 7 +------
 2 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/src/calibre/srv/books.py b/src/calibre/srv/books.py
index eb59b425d7..db4567f53d 100644
--- a/src/calibre/srv/books.py
+++ b/src/calibre/srv/books.py
@@ -244,7 +244,7 @@ def mathjax(ctx, rd, which):
         return rd.etagged_dynamic_response(manifest['etag'], manifest_as_json, content_type='application/json; charset=UTF-8')
     if which not in manifest['files']:
         raise HTTPNotFound('No MathJax file named: %s' % which)
-    path = os.path.abspath(os.path.join(rd.tdir, 'mathjax', which))
-    if not path.startswith(rd.tdir):
+    path = os.path.abspath(P('mathjax/' + which, allow_user_override=False))
+    if not path.startswith(P('mathjax', allow_user_override=False)):
         raise HTTPNotFound('No MathJax file named: %s' % which)
     return rd.filesystem_file_with_constant_etag(lopen(path, 'rb'), manifest['etag'])
diff --git a/src/calibre/utils/rapydscript.py b/src/calibre/utils/rapydscript.py
index 8c7bfc5f1c..946be0f5a4 100644
--- a/src/calibre/utils/rapydscript.py
+++ b/src/calibre/utils/rapydscript.py
@@ -211,12 +211,7 @@ def compile_srv():
     rb = os.path.join(base, 'src', 'calibre', 'srv', 'render_book.py')
     with lopen(rb, 'rb') as f:
         rv = str(int(re.search(br'^RENDER_VERSION\s+=\s+(\d+)', f.read(), re.M).group(1)))
-    try:
-        mathjax_version = P('content-server/mathjax.version', data=True, allow_user_override=False).decode('utf-8')
-    except EnvironmentError as e:
-        if e.errno != errno.ENOENT:
-            raise
-        mathjax_version = '0'
+    mathjax_version = json.loads(P('mathjax/manifest.json', data=True, allow_user_override=False))['etag']
     base = os.path.join(base, 'resources', 'content-server')
     fname = os.path.join(rapydscript_dir, 'srv.pyj')
     with lopen(fname, 'rb') as f: