prototype of executor and context for sharing data

apicast/conf.d/apicast.conf

@@ -5,9 +5,9 @@ set_by_lua_block $deployment {
 }
 
 # TODO: enable in the future when we support SSL
-# ssl_certificate_by_lua_block { require('policy_chain').call() }
-# ssl_session_fetch_by_lua_block { require('policy_chain').call() }
-# ssl_session_store_by_lua_block { require('policy_chain').call() }
+# ssl_certificate_by_lua_block { require('executor').call() }
+# ssl_session_fetch_by_lua_block { require('executor').call() }
+# ssl_session_store_by_lua_block { require('executor').call() }
 
 location = /threescale_authrep {
   internal;
@@ -39,12 +39,12 @@ location @out_of_band_authrep_action {
 
   set_by_lua $original_request_time 'return ngx.var.request_time';
 
-  content_by_lua_block { require('policy_chain'):post_action() }
+  content_by_lua_block { require('executor'):post_action() }
 
   log_by_lua_block {
     ngx.var.post_action_impact = ngx.var.request_time - ngx.var.original_request_time
     ngx.log(ngx.INFO, '[authrep] ', ngx.var.request_uri, ' ', ngx.var.status)
-    require('policy_chain'):log()
+    require('executor'):log()
   }
 }
 
@@ -73,12 +73,12 @@ location / {
 
   proxy_ignore_client_abort on;
 
-  rewrite_by_lua_block { require('policy_chain'):rewrite() }
-  access_by_lua_block { require('policy_chain'):access() }
-  body_filter_by_lua_block { require('policy_chain'):body_filter() }
-  header_filter_by_lua_block { require('policy_chain'):header_filter() }
+  rewrite_by_lua_block { require('executor'):rewrite() }
+  access_by_lua_block { require('executor'):access() }
+  body_filter_by_lua_block { require('executor'):body_filter() }
+  header_filter_by_lua_block { require('executor'):header_filter() }
 
-  content_by_lua_block { require('policy_chain'):content() }
+  content_by_lua_block { require('executor'):content() }
 
   proxy_pass $proxy_pass;
   proxy_http_version 1.1;

apicast/http.d/init.conf

@@ -8,7 +8,7 @@ init_by_lua_block {
     require("resty.core")
     require('resty.resolver').init()
 
-    local module = require('policy_chain')
+    local module = require('executor')
 
     if not module then
       ngx.log(ngx.EMERG, 'fatal error when loading the root module')
@@ -21,7 +21,7 @@ init_by_lua_block {
 }
 
 init_worker_by_lua_block {
-    require('policy_chain'):init_worker()
+    require('executor'):init_worker()
 }
 
 lua_shared_dict init 16k;

apicast/http.d/upstream.conf

@@ -2,15 +2,15 @@
 upstream upstream {
   server 0.0.0.1:1;
 
-  balancer_by_lua_block { require('policy_chain'):balancer() }
+  balancer_by_lua_block { require('executor'):balancer() }
 
   keepalive 1024;
 }
 
 upstream backend_upstream {
   server 0.0.0.1:1;
 
-  balancer_by_lua_block { require('policy_chain'):balancer() }
+  balancer_by_lua_block { require('executor'):balancer() }
 
   keepalive 1024;
 }

apicast/src/apicast.lua

@@ -3,8 +3,6 @@ local balancer = require('balancer')
 local math = math
 local setmetatable = setmetatable
 
-local configuration_loader = require('configuration_loader').new()
-local configuration_store = require('configuration_store')
 local user_agent = require('user_agent')
 
 local noop = function() end
@@ -21,7 +19,6 @@ local mt = {
 --- This is called when APIcast boots the master process.
 function _M.new()
   return setmetatable({
-    configuration = configuration_store.new(),
     -- So there is no way to use ngx.ctx between request and post_action.
     -- We somehow need to share the instance of the proxy between those.
     -- This table is used to store the proxy object with unique reqeust id key
@@ -31,39 +28,33 @@ function _M.new()
   }, mt)
 end
 
-function _M:init()
+function _M.init()
   user_agent.cache()
 
   math.randomseed(ngx.now())
   -- First calls to math.random after a randomseed tend to be similar; discard them
   for _=1,3 do math.random() end
-
-  configuration_loader.init(self.configuration)
 end
 
-function _M:init_worker()
-  configuration_loader.init_worker(self.configuration)
+function _M.init_worker()
 end
 
 function _M.cleanup()
   -- now abort all the "light threads" running in the current request handler
   ngx.exit(499)
 end
 
-function _M:rewrite()
-  ngx.on_abort(_M.cleanup)
+function _M:rewrite(context)
+  ngx.on_abort(self.cleanup)
 
   ngx.var.original_request_id = ngx.var.request_id
 
-  local host = ngx.var.host
   -- load configuration if not configured
   -- that is useful when lua_code_cache is off
   -- because the module is reloaded and has to be configured again
 
-  local configuration = configuration_loader.rewrite(self.configuration, host)
-
-  local p = proxy.new(configuration)
-  p.set_upstream(p:set_service(host))
+  local p = proxy.new(context.configuration)
+  p.set_upstream(p:set_service(context.host))
   ngx.ctx.proxy = p
 end
 

apicast/src/balancer.lua

@@ -2,7 +2,7 @@ local round_robin = require 'resty.balancer.round_robin'
 
 local _M = { default_balancer = round_robin.new() }
 
-function _M.call(_, balancer)
+function _M.call(_, _, balancer)
   balancer = balancer or _M.default_balancer
   local host = ngx.var.proxy_host -- NYI: return to lower frame
   local peers = balancer:peers(ngx.ctx[host])

apicast/src/configuration_loader.lua

@@ -54,9 +54,9 @@ local function ttl()
 end
 
 function _M.global(contents)
-  local module = require('policy_chain')
+  local context = require('executor'):context()
 
-  return _M.configure(module.configuration, contents)
+  return _M.configure(context.configuration, contents)
 end
 
 function _M.configure(configuration, contents)

apicast/src/executor.lua

@@ -0,0 +1,35 @@
+local setmetatable = setmetatable
+
+local policy_chain = require('policy_chain')
+local linked_list = require('linked_list')
+
+local _M = { }
+
+local mt = { __index = _M }
+
+-- forward all policy methods to the policy chain
+for i=1, #(policy_chain.PHASES) do
+    local phase_name = policy_chain.PHASES[i]
+
+    _M[phase_name] = function(self, ...)
+        return self.policy_chain[phase_name](self.policy_chain, self:context(), ...)
+    end
+end
+
+function _M.new()
+    local local_chain = policy_chain.build()
+
+    local load_configuration = policy_chain.load('policy.load_configuration', local_chain)
+
+    local global_chain = policy_chain.build({ load_configuration, local_chain })
+
+    return setmetatable({ policy_chain = global_chain }, mt)
+end
+
+function _M:context()
+    local config = self.policy_chain:export()
+
+    return linked_list.readwrite({}, config)
+end
+
+return _M.new()

apicast/src/linked_list.lua

@@ -0,0 +1,45 @@
+local setmetatable = setmetatable
+
+local _M = {
+
+}
+
+local noop = function() end
+
+
+local empty_t = setmetatable({}, { __newindex = noop })
+local __index = function(t,k)
+    return t.current[k] or t.next[k]
+end
+
+local ro_mt = {
+    __index = __index,
+    __newindex = noop,
+}
+
+local rw_mt = {
+    __index = __index,
+    __newindex = function(t, k, v)
+        t.current[k] = v
+    end
+}
+
+local function linked_list(item, next, mt)
+    return setmetatable({
+        current = item or empty_t,
+        next = next or empty_t
+    }, mt)
+end
+
+local function readonly_linked_list(item, next)
+    return linked_list(item, next, ro_mt)
+end
+
+local function readwrite_linked_list(item, next)
+    return linked_list(item, next, rw_mt)
+end
+
+_M.readonly = readonly_linked_list
+_M.readwrite = readwrite_linked_list
+
+return _M

apicast/src/management.lua

@@ -1,7 +1,7 @@
 local _M = {}
 
 local cjson = require('cjson')
-local module = require('policy_chain')
+local context = require('executor'):context()
 local router = require('router')
 local configuration_parser = require('configuration_parser')
 local configuration_loader = require('configuration_loader')
@@ -28,7 +28,7 @@ function _M.live()
 end
 
 function _M.status(config)
-  local configuration = config or module.configuration
+  local configuration = config or context.configuration
   -- TODO: this should be fixed for multi-tenant deployment
   local has_configuration = configuration.configured
   local has_services = #(configuration:all()) > 0
@@ -43,7 +43,7 @@ function _M.status(config)
 end
 
 function _M.config()
-  local config = module.configuration
+  local config = context.configuration
   local contents = cjson.encode(config.configured and { services = config:all() } or nil)
 
   ngx.header.content_type = 'application/json; charset=utf-8'
@@ -65,7 +65,7 @@ function _M.update_config()
   local config, err = configuration_parser.decode(data)
 
   if config then
-    local configured, error = configuration_loader.configure(module.configuration, config)
+    local configured, error = configuration_loader.configure(context.configuration, config)
     -- TODO: respond with proper 304 Not Modified when config is the same
     if configured and #(configured.services) > 0 then
       json_response({ status = 'ok', config = config, services = #(configured.services)})
@@ -80,7 +80,7 @@ end
 function _M.delete_config()
   ngx.log(ngx.DEBUG, 'management config delete')
 
-  module.configuration:reset()
+  context.configuration:reset()
   -- TODO: respond with proper 304 Not Modified when config is the same
   local response = cjson.encode({ status = 'ok', config = cjson.null })
   ngx.header.content_type = 'application/json; charset=utf-8'
@@ -96,7 +96,7 @@ function _M.boot()
 
   ngx.log(ngx.DEBUG, 'management boot config:' .. inspect(data))
 
-  configuration_loader.configure(module.configuration, config)
+  configuration_loader.configure(context.configuration, config)
 
   ngx.say(response)
 end

apicast/src/policy.lua

@@ -0,0 +1,26 @@
+local _M = {}
+
+local setmetatable = setmetatable
+local policy_chain = require('policy_chain')
+
+local noop = function() end
+
+function _M.new(name)
+    local policy = {
+        _NAME = name or 'policy',
+        _VERSION = '0.0',
+    }
+    local mt = { __index = policy }
+
+    function policy.new()
+        return setmetatable({}, mt)
+    end
+
+    for i=1,#(policy_chain.PHASES) do
+        policy[policy_chain.PHASES[i]] = noop
+    end
+
+    return policy, mt
+end
+
+return _M

apicast/src/policy/load_configuration.lua

@@ -0,0 +1,33 @@
+local setmetatable = setmetatable
+
+local _M, mt = require('policy').new()
+
+local configuration_loader = require('configuration_loader').new()
+local configuration_store = require('configuration_store')
+
+function _M.new()
+    return setmetatable({
+        configuration = configuration_store.new(),
+    }, mt)
+end
+
+function _M:export()
+    return {
+        configuration = self.configuration
+    }
+end
+
+function _M:init()
+    configuration_loader.init(self.configuration)
+end
+
+function _M:init_worker()
+    configuration_loader.init_worker(self.configuration)
+end
+
+function _M:rewrite(context)
+    context.host = context.host or ngx.var.host
+    context.configuration = configuration_loader.rewrite(context.configuration, context.host)
+end
+
+return _M