fix(conf) overcome penlight's 'list_delim' setting

kong/conf_loader.lua

@@ -116,6 +116,11 @@ local function check_and_infer(conf)
     local v_schema = CONF_INFERENCES[k] or {}
     local typ = v_schema.typ
 
+    if type(value) == "string" then
+      value = string.gsub(value, "#.-$", "") -- remove trailing comment if any
+      value = pl_stringx.strip(value)
+    end
+
     -- transform {boolean} values ("on"/"off" aliasing to true/false)
     -- transform {ngx_boolean} values ("on"/"off" aliasing to on/off)
     -- transform {explicit string} values (number values converted to strings)
@@ -135,13 +140,9 @@ local function check_and_infer(conf)
       value = setmetatable(pl_stringx.split(value, ","), nil) -- remove List mt
     end
 
-    if type(value) == "string" then
-      -- default type is string, and an empty if unset
-      value = value ~= "" and tostring(value) or nil
-      if value then
-        value = string.gsub(value, "#.-$", "")
-        value = pl_stringx.strip(value)
-      end
+    if value == "" then
+      -- unset values are removed
+      value = nil
     end
 
     typ = typ or "string"
@@ -279,7 +280,10 @@ local function load(path, custom_conf)
 
     log.verbose("reading config file at %s", path)
     local s = pl_stringio.open(f)
-    from_file_conf, err = pl_config.read(s)
+    from_file_conf, err = pl_config.read(s, {
+      smart = false,
+      list_delim = "_blank_" -- mandatory but we want to ignore it
+    })
     s:close()
     if not from_file_conf then return nil, err end
   end

spec/01-unit/02-conf_loader_spec.lua

@@ -94,6 +94,12 @@ describe("Configuration loader", function()
     assert.equal("cassandra", conf.database)
     assert.equal("debug", conf.log_level)
   end)
+  it("overcomes penlight's list_delim option", function()
+    local conf = assert(conf_loader("spec/fixtures/to-strip.conf"))
+    assert.False(conf.dnsmasq)
+    assert.True(conf.plugins.foobar)
+    assert.True(conf.plugins["hello-world"])
+  end)
 
   describe("inferences", function()
     it("infer booleans (on/off/true/false strings)", function()

spec/fixtures/to-strip.conf

@@ -1,3 +1,17 @@
 database = cassandra # strip me
 log_level =        debug       # strip this
                                # comment too
+dnsmasq = off                        # Toggles if Kong should start/stop dnsmasq,
+                                     # which can be used as the Nginx DNS resolver.
+                                     # Using dnsmasq allows Nginx to resolve
+                                     # domains defined in /etc/hosts.
+                                     # dnsmasq must be installed and available in
+                                     # your $PATH.
+dns_resolver = 8.8.8.8
+
+custom_plugins = foobar,hello-world  # Comma-separated list of additional plugins
+                                     # this node should load.
+                                     # Use this property to load custom plugins
+                                     # that are not bundled with Kong.
+                                     # Plugins will be loaded from the
+                                     # `kong.plugins.{name}.*` namespace.