pkg/cache/cache.go

@@ -0,0 +1,38 @@
+//           ___   ____               ___       ___
+// \ \  / / | _   |  __| \ \  / / || | __  || || _ |
+//  \ \/ /  |___  | |__   \ \/ /  || |___  || ||___|
+//   \  /   | _   | _  |   \  /   ||  __ | || ||\\
+//    \/    |___  |___ |    \/    || ____| || || \\
+//
+// Copyright (c) 2021 Piotr Biernat. https://pbiernat.dev. MIT License
+// Repo: https://git.pbiernat.dev/golang/vegvisir
+
+package cache
+
+import (
+	"log"
+	"vegvisir/pkg/config"
+)
+
+const (
+	TYPE_REDIS  = "redis"
+	TYPE_MEMORY = "memory"
+)
+
+func GetCacheDatastore(config config.Cache) *CacheDatastore {
+	var datastore CacheDatastore
+
+	if config.Type == TYPE_REDIS {
+		datastore = NewRedisDatastore(config.Host, config.Port)
+	} else {
+		datastore = NewMemoryDatastore()
+	}
+
+	// fail-safe switch to memory datasource
+	if !datastore.IsConnected() {
+		log.Println("Cache server is not responding, switching to memory cache.")
+		datastore = NewMemoryDatastore()
+	}
+
+	return &datastore
+}

pkg/cache/memory_datastore.go

@@ -11,25 +11,39 @@ package cache
 
 import (
 	"errors"
+	"time"
 )
 
+type TtlItem struct {
+	ts  int // timestamp
+	ttl int // ttl in seconds
+}
+
 func NewMemoryDatastore() *MemoryDatastore {
 	return &MemoryDatastore{
 		cache: make(map[string]interface{}),
+		ts:    make(map[string]TtlItem),
 	}
 }
 
 type MemoryDatastore struct {
 	cache map[string]interface{}
+	ts    map[string]TtlItem
 }
 
 func (ds *MemoryDatastore) SetKey(key string, data interface{}, ttl int) error {
 	ds.cache[key] = data
+	ds.ts[key] = TtlItem{
+		ts:  time.Now().Second(),
+		ttl: ttl,
+	}
 
 	return nil
 }
 
 func (ds *MemoryDatastore) GetKey(key string) (interface{}, error) {
+	ds.gc(key) // remove key is time of creation is outdated
+
 	if data, ok := ds.cache[key]; ok {
 		return data, nil
 	}
@@ -40,3 +54,9 @@ func (ds *MemoryDatastore) GetKey(key string) (interface{}, error) {
 func (ds *MemoryDatastore) IsConnected() bool {
 	return true
 }
+
+func (ds *MemoryDatastore) gc(key string) {
+	if item, ok := ds.ts[key]; ok && item.ts < time.Now().Second()-item.ttl {
+		delete(ds.cache, key)
+	}
+}

pkg/cache/response.go

@@ -14,10 +14,12 @@ import (
 	"log"
 )
 
+type Headers map[string]string
+
 type ResponseCache struct {
-	URL  string
+	URL     string
-	Body string
+	Body    string
-	// Headers map[string]string
+	Headers Headers
 }
 
 type ResponseCacheManager struct {
@@ -49,7 +51,7 @@ func (rm *ResponseCacheManager) Save(name string, r ResponseCache) bool {
 	name = rm.prefix + name
 	err = rm.datastore.SetKey(name, string(data), rm.ttl)
 	if err != nil {
-		log.Println("Response-cache:", err, name) // FIXME
+		log.Println("Response-cache:", err, name)
 		return false
 	}
 

pkg/config/config.go

@@ -17,6 +17,7 @@ import (
 
 type Config struct {
 	Server   Server
+	Cache    Cache
 	Backends map[string]Backend
 
 	confPath string
@@ -27,6 +28,17 @@ type Server struct {
 	Port    int
 }
 
+type Cache struct {
+	Type        string
+	Host        string
+	Port        int
+	Username    string
+	Password    string
+	Database    string
+	RouteTtl    int
+	ResponseTtl int
+}
+
 type Backend struct {
 	PrefixUrl      string
 	BackendAddress string

pkg/main.go

@@ -19,15 +19,13 @@ import (
 )
 
 var (
-	cFile = flag.String("c", "vegvisir.json", "Path to config file")
+	cPath = flag.String("c", "vegvisir.json", "Path to config file")
-
 	// for profiling...
 	cpuprofile = flag.String("cpuprofile", "", "write cpu profile to `file`")
 	memprofile = flag.String("memprofile", "", "write memory profile to `file`")
 )
 
 func main() {
-
 	flag.Parse()
 	// cpu profiling
 	if *cpuprofile != "" {
@@ -42,7 +40,7 @@ func main() {
 		defer pprof.StopCPUProfile()
 	}
 
-	server.NewServer(*cFile).Run()
+	server.NewServer(*cPath).Run()
 
 	// memory profiling
 	if *memprofile != "" {

pkg/server/server.go

@@ -23,8 +23,8 @@ import (
 )
 
 const (
-	Version = "0.1-dev"
+	ServerVersion = "0.1-dev"
-	Name    = "Vegvisir/" + Version
+	ServerName    = "Vegvisir/" + ServerVersion
 )
 
 type Server struct {
@@ -40,23 +40,13 @@ func NewServer(cPath string) *Server {
 		log.Fatalln("Unable to find config file: ", cPath, err)
 	}
 
-	server := &Server{
+	datastore := cache.GetCacheDatastore(config.Cache)
+
+	return &Server{
 		config: config,
+		router: NewRouter(config, *datastore, config.Cache.RouteTtl),
+		respCM: cache.NewResponseCacheManager(*datastore, config.Cache.ResponseTtl),
 	}
-
-	redisDS := cache.NewRedisDatastore("127.0.0.1", 6379) // FIXME use config or env...
-	if !redisDS.IsConnected() {
-		log.Println("Redis server not responding, switching to memory cache...")
-
-		memDS := cache.NewMemoryDatastore()
-		server.router = NewRouter(config, memDS, 30)             //FIXME for memory datasource ttl is useles right now...
-		server.respCM = cache.NewResponseCacheManager(memDS, 30) //FIXME for memory datasource ttl is useles right now...
-	} else {
-		server.router = NewRouter(config, redisDS, 30)             //FIXME use ttl(seconds) from config or env...
-		server.respCM = cache.NewResponseCacheManager(redisDS, 30) //FIXME use ttl(seconds) from config or env...
-	}
-
-	return server
 }
 
 func (s *Server) Run() {
@@ -89,11 +79,11 @@ func (s *Server) Shutdown(ctx context.Context) { // TODO: wait for all connectio
 }
 
 func (s *Server) mainHandler(ctx *fasthttp.RequestCtx) {
-	ctx.Response.Header.Add(fasthttp.HeaderServer, Name)
+	// http := client.NewHttpClient(ctx)
 
 	// move all below logic to concrete handler or sth....
 	reqUrl, sReqUrl, sReqMethod := ctx.RequestURI(), string(ctx.RequestURI()), string(ctx.Method())
-	log.Println("Incomming request:", sReqMethod, sReqUrl)
+	log.Println("Incoming request:", sReqMethod, sReqUrl)
 
 	found, route := s.router.FindByRequestURL(reqUrl)
 	if !found {
@@ -106,7 +96,12 @@ func (s *Server) mainHandler(ctx *fasthttp.RequestCtx) {
 	if ok, data := s.respCM.Load(sReqUrl); ok {
 		log.Println("Read resp from cache: ", route.TargetUrl)
 
-		ctx.SetBody([]byte(data.Body)) // FIXME missing headers etc...
+		// copy headers and body from cache
+		ctx.Response.Header.DisableNormalizing()
+		for key, value := range data.Headers {
+			ctx.Response.Header.Set(key, value)
+		}
+		ctx.SetBody([]byte(data.Body))
 	} else {
 		log.Println("Send req to backend url: ", route.TargetUrl)
 
@@ -126,15 +121,23 @@ func (s *Server) mainHandler(ctx *fasthttp.RequestCtx) {
 			return
 		}
 
-		ctx.Response.Header.SetBytesV(fasthttp.HeaderContentType, bckResp.Header.ContentType())
+		headers := make(cache.Headers)
-		ctx.SetStatusCode(bckResp.StatusCode())
+		// rewrite headers from backend to gateway response
+		bckResp.Header.Set(fasthttp.HeaderServer, ServerName)
+		bckResp.Header.Del(fasthttp.HeaderXPoweredBy)
+		ctx.Response.Header.DisableNormalizing()
+		bckResp.Header.VisitAll(func(key, value []byte) {
+			headers[string(key)] = string(value)
+			ctx.Response.Header.SetBytesKV(key, value)
+		})
+		// ctx.SetStatusCode(bckResp.StatusCode())
 		ctx.SetBody(bckResp.Body())
 
 		// save response to cache
 		respCache := cache.ResponseCache{
-			URL:  sReqUrl,
+			URL:     sReqUrl,
-			Body: string(bckResp.Body()),
+			Body:    string(bckResp.Body()),
-			// Headers: []
+			Headers: headers,
 		} // FIXME: prepare resp cache struct in respCM.Save method or other service...
 		s.respCM.Save(sReqUrl, respCache)
 	}

vegvisir.json.dist

@@ -29,5 +29,15 @@
                 "target": "article-global/$1"
             }]
         }
+    },
+    "cache": {
+        "type": "redis",
+        "host": "localhost",
+        "port": 6379,
+        "username": "",
+        "password": "",
+        "database": "0",
+        "routeTtl": 300,
+        "responseTtl": 300
     }
 }