feat(init) checking that core shared dictionaries exist

CHANGELOG.md

@@ -25,6 +25,8 @@
 - Serf commands executed by a running Kong node are now logged in the Nginx
   error logs with a `DEBUG` level.
   [#2410](https://github.com/Mashape/kong/pull/2410)
+- Checking that core Lua shared dictionaries are declared in the configuration.
+  [#2466](https://github.com/Mashape/kong/pull/2466)
 - Plugins:
   - :fireworks: **New Request termination plugin**. This plugin allows to
     temporarily disable an API and return a pre-configured response status and

kong/constants.lua

@@ -69,5 +69,6 @@ return {
   },
   CACHE = {
     CLUSTER = "cluster"
-  }
+  },
+  DICTS = { "kong", "cache", "cache_locks", "process_events", "cassandra"}
 }

kong/kong.lua

@@ -121,6 +121,15 @@ end
 local Kong = {}
 
 function Kong.init()
+  -- Check shared dictionaries
+  for _, dict in ipairs(constants.DICTS) do
+    if not ngx.shared[dict] then
+      error("missing shared dict in Nginx configuration, are you "..
+            "using a custom template? Make sure the 'lua_shared_dict "..
+            dict.." [SIZE];' directive is defined.")
+    end
+  end
+
   local pl_path = require "pl.path"
   local conf_loader = require "kong.conf_loader"
 

spec/02-integration/01-cmd/02-start_stop_spec.lua

@@ -199,5 +199,28 @@ describe("kong start/stop", function()
 
       assert(kill.is_running(helpers.test_conf.nginx_pid))
     end)
+    it("checks that the shared dictionaries exist", function()
+      local constants = require "kong.constants"
+      local pl_file = require "pl.file"
+
+      local templ_fixture = "spec/fixtures/custom_nginx.template"
+      local new_templ_fixture = "spec/fixtures/custom_nginx.template.tmp"
+
+      for _, dict in ipairs(constants.DICTS) do
+        -- Remove shared dictionary entry
+        assert(os.execute(
+          "sed '/lua_shared_dict "..dict.." .*;/d' "..templ_fixture.." > "
+          ..new_templ_fixture))
+
+        local _, stderr = helpers.kong_exec("start --nginx-conf "
+                                            ..new_templ_fixture)
+        assert.matches(
+          "missing shared dict in Nginx configuration, "..
+          "are you using a custom template? Make sure the 'lua_shared_dict "
+          ..dict.." [SIZE];' directive is defined.", stderr, nil, true)
+      end
+
+      pl_file.delete(new_templ_fixture)
+    end)
   end)
 end)