From b98348de029003bc0333ccfb2ff2e071d1a74c8e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Gina=20H=C3=A4u=C3=9Fge?= <osd@foosel.net>
Date: Fri, 6 Nov 2015 11:46:12 +0100
Subject: [PATCH] Cache rendered page and translation files indefinitely

---
 src/octoprint/server/util/flask.py | 56 ++++++++++++++++++++++++++++--
 src/octoprint/server/views.py      |  7 ++--
 2 files changed, 59 insertions(+), 4 deletions(-)

diff --git a/src/octoprint/server/util/flask.py b/src/octoprint/server/util/flask.py
index 7fe8ae34..f4d7a9d9 100644
--- a/src/octoprint/server/util/flask.py
+++ b/src/octoprint/server/util/flask.py
@@ -26,7 +26,7 @@ import octoprint.server
 import octoprint.users
 import octoprint.plugin
 
-from werkzeug.contrib.cache import SimpleCache
+from werkzeug.contrib.cache import BaseCache
 
 
 #~~ monkey patching
@@ -259,7 +259,59 @@ def passive_login():
 
 #~~ cache decorator for cacheable views
 
-_cache = SimpleCache()
+class LessSimpleCache(BaseCache):
+	"""
+	Slightly improved version of :class:`SimpleCache`.
+
+	Setting ``default_timeout`` or ``timeout`` to ``-1`` will have no timeout be applied at all.
+	"""
+
+	def __init__(self, threshold=500, default_timeout=300):
+		BaseCache.__init__(self, default_timeout=default_timeout)
+		self._cache = {}
+		self.clear = self._cache.clear
+		self._threshold = threshold
+
+	def _prune(self):
+		if self.over_threshold():
+			now = time.time()
+			for idx, (key, (expires, _)) in enumerate(self._cache.items()):
+				if expires is not None and expires <= now or idx % 3 == 0:
+					self._cache.pop(key, None)
+
+	def get(self, key):
+		import pickle
+		now = time.time()
+		expires, value = self._cache.get(key, (0, None))
+		if expires is None or expires > now:
+			return pickle.loads(value)
+
+	def set(self, key, value, timeout=None):
+		import pickle
+		self._prune()
+		self._cache[key] = (self.calculate_timeout(timeout=timeout),
+		                    pickle.dumps(value, pickle.HIGHEST_PROTOCOL))
+
+	def add(self, key, value, timeout=None):
+		self.set(key, value, timeout=None)
+		self._cache.setdefault(key, self._cache[key])
+
+	def delete(self, key):
+		self._cache.pop(key, None)
+
+	def calculate_timeout(self, timeout=None):
+		if timeout is None:
+			timeout = self.default_timeout
+		if timeout is -1:
+			return None
+		return time.time() + timeout
+
+	def over_threshold(self):
+		if self._threshold is None:
+			return False
+		return len(self._cache) > self._threshold
+
+_cache = LessSimpleCache()
 
 def cached(timeout=5 * 60, key=lambda: "view/%s" % flask.request.path, unless=None, refreshif=None, unless_response=None):
 	def decorator(f):
diff --git a/src/octoprint/server/views.py b/src/octoprint/server/views.py
index f89bd9da..17927536 100644
--- a/src/octoprint/server/views.py
+++ b/src/octoprint/server/views.py
@@ -27,7 +27,8 @@ _valid_id_re = re.compile("[a-z_]+")
 _valid_div_re = re.compile("[a-zA-Z_-]+")
 
 @app.route("/")
-@util.flask.cached(refreshif=lambda: util.flask.cache_check_headers() or "_refresh" in request.values,
+@util.flask.cached(timeout=-1,
+                   refreshif=lambda: util.flask.cache_check_headers() or "_refresh" in request.values,
                    key=lambda: "view/%s/%s" % (request.path, g.locale),
                    unless_response=util.flask.cache_check_response_headers)
 def index():
@@ -401,7 +402,9 @@ def robotsTxt():
 
 
 @app.route("/i18n/<string:locale>/<string:domain>.js")
-@util.flask.cached(refreshif=lambda: util.flask.cache_check_headers() or "_refresh" in request.values, key=lambda: "view/%s/%s" % (request.path, g.locale))
+@util.flask.cached(timeout=-1,
+                   refreshif=lambda: util.flask.cache_check_headers() or "_refresh" in request.values,
+                   key=lambda: "view/%s/%s" % (request.path, g.locale))
 def localeJs(locale, domain):
 	messages = dict()
 	plural_expr = None