Add HTTP Cache support to http_ng

CHANGELOG.md

@@ -10,6 +10,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 - Bump OpenResty version to [1.11.2.3](https://github.com/3scale/s2i-openresty/releases/tag/1.11.2.3-1) [PR #359](https://github.com/3scale/apicast/pull/359) 
 
+### Added
+
+- Experimental caching proxy to the http client [PR #357](https://github.com/3scale/apicast/pull/357)
+
 ## [3.0.0-rc1] - 2017-04-04
 
 ### Added

apicast/src/resty/http_ng.lua

@@ -90,7 +90,7 @@ http.method = function(method, client)
     local req_params = get_request_params(method, client, url, options)
     local req = http.request.new(req_params)
 
-    return client.backend.send(req)
+    return client.backend:send(req)
   end
 end
 
@@ -111,7 +111,7 @@ http.method_with_body = function(method, client)
     req_params.body = body
     local req = http.request.new(req_params)
 
-    return client.backend.send(req)
+    return client.backend:send(req)
   end
 end
 

apicast/src/resty/http_ng/backend/async_resty.lua

@@ -106,7 +106,7 @@ local function future(thread, request)
   })
 end
 
-_M.send = function(request)
+_M.send = function(_, request)
   local thread = spawn(_M.async, request)
   return future(thread, request)
 end

apicast/src/resty/http_ng/backend/cache.lua

@@ -0,0 +1,37 @@
+local setmetatable = setmetatable
+
+------------
+--- HTTP
+-- HTTP client
+-- @module http_ng.backend
+
+local _M = {}
+
+local mt = { __index = _M }
+
+function _M.new(backend, options)
+  local opts = options or {}
+  return setmetatable({
+    backend = backend, cache_store = opts.cache_store
+  }, mt)
+end
+
+--- Send request and return the response
+-- @tparam http_ng.request request
+-- @treturn http_ng.response
+function _M:send(request)
+  local cache_store = self.cache_store
+  local backend = self.backend
+
+  local response, err
+
+  if cache_store then
+    response, err = cache_store:send(backend, request)
+  else
+    response, err = backend:send(request)
+  end
+
+  return response, err
+end
+
+return _M

apicast/src/resty/http_ng/backend/ngx.lua

@@ -14,7 +14,7 @@ local METHODS = {
 local PROXY_LOCATION = '/___http_call'
 
 backend.capture = ngx.location.capture
-backend.send = function(request)
+backend.send = function(_, request)
   local res = backend.capture(PROXY_LOCATION, {
     method = METHODS[request.method],
     body = request.body,

apicast/src/resty/http_ng/backend/resty.lua

@@ -10,7 +10,7 @@ local http = require 'resty.resolver.http'
 --- Send request and return the response
 -- @tparam http_ng.request request
 -- @treturn http_ng.response
-backend.send = function(request)
+backend.send = function(_, request)
   local httpc = http.new()
   local ssl_verify = request.options and request.options.ssl and request.options.ssl.verify
 

apicast/src/resty/http_ng/backend/test.lua

@@ -2,6 +2,7 @@ local pairs = pairs
 local type = type
 local assert = assert
 local setmetatable = setmetatable
+local getmetatable = getmetatable
 local insert = table.insert
 local remove = table.remove
 local error = error
@@ -13,7 +14,15 @@ local _M = {}
 local function contains(expected, actual)
   if actual == expected then return true end
   local t1,t2 = type(actual), type(expected)
-  if t1 ~= t2 then return false, format("can't compare %q with %q", t1, t2) end
+
+  if t1 ~= t2 then
+    local mt = getmetatable(actual) or {}
+    if t2 == 'string' and mt.__tostring then
+      return mt.__tostring(actual) == expected
+    else
+      return false, format("can't compare %q with %q", t1, t2)
+    end
+  end
 
   if t1 == 'table' then
     for k,v in pairs(expected) do
@@ -60,7 +69,7 @@ _M.new = function()
     return expectation
   end
 
-  backend.send = function(request)
+  backend.send = function(_, request)
     local expectation = remove(expectations, 1)
 
     if not expectation then error('no expectation') end