Merge pull request #88 from hamishforbes/master

Bugfix: Multiple cache-control headers should be concatenated

lib/ledge/ledge.lua

@@ -11,6 +11,7 @@ local type = type
 local next = next
 local table = table
 local ngx = ngx
+local tbl_concat = table.concat
 
 module(...)
 
@@ -1467,10 +1468,14 @@ function save_to_cache(self, res)
     }
 
     -- Also don't cache any headers marked as Cache-Control: (no-cache|no-store|private)="header".
-    if res.header["Cache-Control"] and res.header["Cache-Control"]:find("=") then
+    local cc = res.header["Cache-Control"]
+    if type(cc) == "table" then
+        cc = tbl_concat(cc, ", ")
+    end
+    if cc and cc:find("=") then
         local patterns = { "no%-cache", "no%-store", "private" }
         for _,p in ipairs(patterns) do
-            for h in res.header["Cache-Control"]:gmatch(p .. "=\"?([%a-]+)\"?") do
+            for h in cc:gmatch(p .. "=\"?([%a-]+)\"?") do
                 table.insert(uncacheable_headers, h)
             end
         end

lib/ledge/response.lua

@@ -6,7 +6,9 @@ local rawset = rawset
 local rawget = rawget
 local tonumber = tonumber
 local error = error
+local type = type
 local ngx = ngx
+local tbl_concat = table.concat
 
 module(...)
 
@@ -102,9 +104,13 @@ end
 function ttl(self)
     -- Header precedence is Cache-Control: s-maxage=NUM, Cache-Control: max-age=NUM,
     -- and finally Expires: HTTP_TIMESTRING.
-    if self.header["Cache-Control"] then
+    local cc = self.header["Cache-Control"]
+    if cc then
+        if type(cc) == "table" then
+            cc = tbl_concat(cc, ", ")
+        end
         local max_ages = {}
-        for max_age in ngx.re.gmatch(self.header["Cache-Control"], 
+        for max_age in ngx.re.gmatch(cc,
             "(s\\-maxage|max\\-age)=(\\d+)", 
             "io") do
             max_ages[max_age[1]] = max_age[2]

t/19-multiple_headers.t

@@ -0,0 +1,68 @@
+use Test::Nginx::Socket;
+use Cwd qw(cwd);
+
+plan tests => 6;
+
+my $pwd = cwd();
+
+$ENV{TEST_LEDGE_REDIS_DATABASE} ||= 1;
+
+our $HttpConfig = qq{
+    lua_package_path "$pwd/../lua-resty-rack/lib/?.lua;$pwd/lib/?.lua;;";
+    init_by_lua "
+        ledge_mod = require 'ledge.ledge'
+        ledge = ledge_mod:new()
+        ledge:config_set('redis_database', $ENV{TEST_LEDGE_REDIS_DATABASE})
+    ";
+};
+
+run_tests();
+
+__DATA__
+=== TEST 1: Multiple cache-control response headers, miss
+--- http_config eval: $::HttpConfig
+--- config
+    location /cache {
+        content_by_lua '
+            ledge:run()
+        ';
+    }
+
+    location /__ledge_origin {
+        content_by_lua '
+            ngx.header["Cache-Control"] = { "public", "max-age=3600"}
+            ngx.say("TEST 1")
+        ';
+    }
+--- request
+GET /cache
+--- response_headers_like
+X-Cache: MISS from .*
+--- response_headers
+Cache-Control: public, max-age=3600
+--- response_body
+TEST 1
+
+=== TEST 1b: Multiple cache-control response headers, hit
+--- http_config eval: $::HttpConfig
+--- config
+    location /cache {
+        content_by_lua '
+            ledge:run()
+        ';
+    }
+
+    location /__ledge_origin {
+        content_by_lua '
+            ngx.header["Cache-Control"] = { "public", "max-age=3600"}
+            ngx.say("TEST 2")
+        ';
+    }
+--- request
+GET /cache
+--- response_headers_like
+X-Cache: HIT from .*
+--- response_headers
+Cache-Control: public, max-age=3600
+--- response_body
+TEST 1