Merge pull request #3 from justcoded/develop

Develop

Makefile

@@ -1,4 +1,4 @@
-.PHONY: init build build-server build-storage up run start down stop
+.PHONY: init build build-server build-storage up run start down stop restart
 
 init:
 	@if [ ! -f '.env' ]; then \
@@ -34,3 +34,5 @@ run:
 down: stop
 stop:
 	docker-compose down
+
+restart: stop run

README.md

@@ -3,26 +3,27 @@ GO Prerender
 
 > Inspired by https://github.com/goprerender/prerender
 
-GO Prerender is a dockerized server app written in Golang that uses Headless Chrome to render HTML and JS files out of any web page. 
-The Prerender server listens for a http request, takes the URL and loads it in Headless Chrome, waits for the page to finish loading by waiting for the network to be idle, and then returns your content.
+GO Prerender is a dockerized server app written in Golang that uses Headless Chrome to render HTML and JS files out of
+any web page.
+The Prerender server listens for a http request, takes the URL and loads it in Headless Chrome, waits for the page to
+finish loading by waiting for the network to be idle, and then returns your content.
 
 #### In memory cache
 
-Caches pages in memory using prerender `storage` container. 
+It caches pages in memory using prerender `storage` container.
 
-### Installation 
+### Installation
 
 * clone repository
 * run `make init`
 * configure `.env` and `docker-compose.yml` to fit your needs or use the default.
 * run `make up` - this will build and start docker containers
 
-
 ### Development
 
 Run `make build-server` to build server Go application.  
 Run `make build-storage` to build storage Go application.  
-Run `make build` to build both Go applications server and storage.   
+Run `make build` to build both Go applications server and storage.
 
 #### Usage
 
@@ -33,3 +34,28 @@ To prerender some URL you need to specify it as a query parameter, like this:
 ```
 http://localhost:3000/render?url=https://www.example.com/
 ```
+
+#### Purge cache
+
+Cached pages are valid for 7 days by default, but you can force clear it.
+
+To purge all cached pages you need to pass the `Cache-Control` header
+with the value `must-revalidate` or the `Clear-Site-Data` header with any value.
+
+Just send a usual request to
+
+```
+http://localhost:3000/render?url=https://www.example.com/
+```
+
+With this header
+
+```
+Cache-Control: must-revalidate
+```
+
+or
+
+```
+Clear-Site-Data: *
+```

src/api/proto/storage.proto

@@ -10,11 +10,13 @@ import "google/protobuf/timestamp.proto";
 // The storage service definition.
 service Storage {
   // Sends a store request message
-  rpc Store (StoreRequest) returns (StoreReply) {}
+  rpc Store(StoreRequest) returns (StoreReply) {}
   // Get a request from storage
-  rpc Get (GetRequest) returns (GetReplay) {}
+  rpc Get(GetRequest) returns (GetReplay) {}
   //
   rpc Len(LenRequest) returns (LenReplay) {}
+  //
+  rpc Purge(PurgeRequest) returns (PurgeReply) {}
 }
 
 message Page {
@@ -57,3 +59,7 @@ message LenRequest {}
 message LenReplay {
   int32 length = 1;
 }
+
+message PurgeRequest {}
+
+message PurgeReply {}

src/cmd/server/main.go

@@ -52,7 +52,7 @@ func main() {
 	logger.Infof("Starting server...")
 	time.Sleep(5 * time.Second)
 
-	logger.Infof("Connecting to storage %v",  address)
+	logger.Infof("Connecting to storage %v", address)
 	// Set up a connection to the server.
 	conn, err := grpc.Dial(address, grpc.WithInsecure(), grpc.WithBlock())
 	if err != nil {
@@ -156,6 +156,12 @@ func handleRequest(ctx context.Context, pc cachers.Сacher, logger prLog.Logger)
 		ctx, cancel := context.WithTimeout(newTabCtx, time.Second*60)
 		defer cancel()
 
+		req := c.Request
+
+		if req.Header.Get("Cache-Control") == "must-revalidate" || req.Header.Get("Clear-Site-Data") != "" {
+			pc.Purge()
+		}
+
 		res, err := renderer.DoRender(ctx, queryString, pc, false, logger)
 		if err != nil {
 			return err

src/cmd/storage/main.go

@@ -16,13 +16,13 @@ import (
 )
 
 const (
-	port = ":50051"
-	duration = time.Hour*24*7
+	port     = ":50051"
+	duration = time.Hour * 24 * 7
 )
 
 var gc = gcache.New(100000).
-		LRU().
-		Build()
+	LRU().
+	Build()
 
 // server is used to implement Saver.
 type server struct {
@@ -51,12 +51,17 @@ func (s *server) Get(ctx context.Context, in *storage.GetRequest) (*storage.GetR
 }
 
 func (s *server) Len(ctx context.Context, in *storage.LenRequest) (*storage.LenReplay, error) {
-	log.Printf("Received: Len request")
+	//log.Printf("Received: Len request")
 	return &storage.LenReplay{Length: int32(gc.Len(true))}, nil
 }
 
-func main() {
+func (s *server) Purge(ctx context.Context, in *storage.PurgeRequest) (*storage.PurgeReply, error) {
+	gc.Purge()
+
+	return &storage.PurgeReply{}, nil
+}
 
+func main() {
 	ctx := context.Background()
 	lis, err := net.Listen("tcp", port)
 	if err != nil {

src/internal/cachers/cacher.go

@@ -4,4 +4,5 @@ type Сacher interface {
 	Put(key string, data []byte) error
 	Get(key string) ([]byte, error)
 	Len() int
- }
+	Purge()
+}

src/internal/cachers/inmemory/repository.go

@@ -12,7 +12,7 @@ type repository struct {
 }
 
 func New(gc gcache.Cache) cachers.Сacher {
-	return repository{gc: gc, dd: time.Hour*24*7}
+	return repository{gc: gc, dd: time.Hour * 24 * 7}
 }
 
 func (r repository) Put(key string, data []byte) error {
@@ -30,3 +30,7 @@ func (r repository) Get(key string) ([]byte, error) {
 func (r repository) Len() int {
 	return r.gc.Len(true)
 }
+
+func (r repository) Purge() {
+	r.gc.Purge()
+}

src/internal/cachers/rstorage/service.go

@@ -47,7 +47,16 @@ func (s server) Len() int {
 	req := storage.LenRequest{}
 	result, err := s.gw.Len(ctx, &req)
 	if err != nil {
-		log.Fatal( err)
+		log.Fatal(err)
 	}
 	return int(result.GetLength())
 }
+
+func (s server) Purge() {
+	ctx := context.Background()
+	req := storage.PurgeRequest{}
+	_, err := s.gw.Purge(ctx, &req)
+	if err != nil {
+		log.Fatal(err)
+	}
+}