Move routing to separate module

Makefile

@@ -1,2 +1,2 @@
-srv: cmd/*.go
+srv: cmd/*.go internal/routing/*.go
-	go build -o srv cmd/*.go
+	go build -o srv ./cmd/

cmd/processRequest.go

@@ -11,10 +11,12 @@ import (
 	"sync"
 	"time"
 
+	"github.com/chubin/wttr.in/internal/routing"
+
 	lru "github.com/hashicorp/golang-lru"
 )
 
-type ResponseWithHeader struct {
+type responseWithHeader struct {
 	InProgress bool      // true if the request is being processed
 	Expires    time.Time // expiration time of the cache entry
 
@@ -29,7 +31,7 @@ type RequestProcessor struct {
 	peakRequest60 sync.Map
 	lruCache      *lru.Cache
 	stats         *Stats
-	router        Router
+	router        routing.Router
 }
 
 // NewRequestProcessor returns new RequestProcessor.
@@ -55,9 +57,9 @@ func (rp *RequestProcessor) Start() {
 	rp.startPeakHandling()
 }
 
-func (rp *RequestProcessor) ProcessRequest(r *http.Request) (*ResponseWithHeader, error) {
+func (rp *RequestProcessor) ProcessRequest(r *http.Request) (*responseWithHeader, error) {
 	var (
-		response *ResponseWithHeader
+		response *responseWithHeader
 		err      error
 	)
 
@@ -67,7 +69,7 @@ func (rp *RequestProcessor) ProcessRequest(r *http.Request) (*ResponseWithHeader
 	if rh := rp.router.Route(r); rh != nil {
 		result := rh.Response(r)
 		if result != nil {
-			return result, nil
+			return fromCadre(result), nil
 		}
 	}
 
@@ -90,7 +92,7 @@ func (rp *RequestProcessor) ProcessRequest(r *http.Request) (*ResponseWithHeader
 	cacheBody, ok := rp.lruCache.Get(cacheDigest)
 	if ok {
 		rp.stats.Inc("cache1")
-		cacheEntry := cacheBody.(ResponseWithHeader)
+		cacheEntry := cacheBody.(responseWithHeader)
 
 		// if after all attempts we still have no answer,
 		// we try to make the query on our own
@@ -101,7 +103,7 @@ func (rp *RequestProcessor) ProcessRequest(r *http.Request) (*ResponseWithHeader
 			time.Sleep(30 * time.Millisecond)
 			cacheBody, ok = rp.lruCache.Get(cacheDigest)
 			if ok && cacheBody != nil {
-				cacheEntry = cacheBody.(ResponseWithHeader)
+				cacheEntry = cacheBody.(responseWithHeader)
 			}
 		}
 		if cacheEntry.InProgress {
@@ -123,7 +125,7 @@ func (rp *RequestProcessor) ProcessRequest(r *http.Request) (*ResponseWithHeader
 			}
 		}
 
-		rp.lruCache.Add(cacheDigest, ResponseWithHeader{InProgress: true})
+		rp.lruCache.Add(cacheDigest, responseWithHeader{InProgress: true})
 
 		response, err = get(r)
 		if err != nil {
@@ -139,7 +141,7 @@ func (rp *RequestProcessor) ProcessRequest(r *http.Request) (*ResponseWithHeader
 	return response, nil
 }
 
-func get(req *http.Request) (*ResponseWithHeader, error) {
+func get(req *http.Request) (*responseWithHeader, error) {
 
 	client := &http.Client{}
 
@@ -173,7 +175,7 @@ func get(req *http.Request) (*ResponseWithHeader, error) {
 		return nil, err
 	}
 
-	return &ResponseWithHeader{
+	return &responseWithHeader{
 		InProgress: false,
 		Expires:    time.Now().Add(time.Duration(randInt(1000, 1500)) * time.Second),
 		Body:       body,
@@ -214,7 +216,7 @@ func dontCache(req *http.Request) bool {
 //    proxy_set_header   X-Forwarded-Proto $scheme;
 //
 //
-func redirectInsecure(req *http.Request) (*ResponseWithHeader, bool) {
+func redirectInsecure(req *http.Request) (*responseWithHeader, bool) {
 	if isPlainTextAgent(req.Header.Get("User-Agent")) {
 		return nil, false
 	}
@@ -236,7 +238,7 @@ The document has moved
 </BODY></HTML>
 `, target))
 
-	return &ResponseWithHeader{
+	return &responseWithHeader{
 		InProgress: false,
 		Expires:    time.Now().Add(time.Duration(randInt(1000, 1500)) * time.Second),
 		Body:       body,
@@ -284,3 +286,14 @@ func ipFromAddr(s string) string {
 	}
 	return s[:pos]
 }
+
+// fromCadre converts Cadre into a responseWithHeader.
+func fromCadre(cadre *routing.Cadre) *responseWithHeader {
+	return &responseWithHeader{
+		Body:       cadre.Body,
+		Expires:    cadre.Expires,
+		StatusCode: 200,
+		InProgress: false,
+	}
+
+}

cmd/route.go

@@ -1,37 +0,0 @@
-package main
-
-import "net/http"
-
-type Handler interface {
-	Response(*http.Request) *ResponseWithHeader
-}
-
-type routeFunc func(*http.Request) bool
-
-type route struct {
-	routeFunc
-	Handler
-}
-
-type Router struct {
-	rt []route
-}
-
-func (r *Router) Route(req *http.Request) Handler {
-	for _, re := range r.rt {
-		if re.routeFunc(req) {
-			return re.Handler
-		}
-	}
-	return nil
-}
-
-func (r *Router) AddPath(path string, handler Handler) {
-	r.rt = append(r.rt, route{routePath(path), handler})
-}
-
-func routePath(path string) routeFunc {
-	return routeFunc(func(req *http.Request) bool {
-		return req.URL.Path == path
-	})
-}

cmd/stat.go

@@ -6,6 +6,8 @@ import (
 	"net/http"
 	"sync"
 	"time"
+
+	"github.com/chubin/wttr.in/internal/routing"
 )
 
 // Stats holds processed requests statistics.
@@ -77,9 +79,8 @@ func (c *Stats) Show() []byte {
 	return b.Bytes()
 }
 
-func (c *Stats) Response(*http.Request) *ResponseWithHeader {
+func (c *Stats) Response(*http.Request) *routing.Cadre {
-	return &ResponseWithHeader{
+	return &routing.Cadre{
-		Body:       c.Show(),
+		Body: c.Show(),
-		StatusCode: 200,
 	}
 }

go.mod

@@ -1,9 +1,8 @@
-module github.com/chubin/wttr.in/v2
+module github.com/chubin/wttr.in
 
 go 1.16
 
 require (
 	github.com/hashicorp/golang-lru v0.6.0
 	github.com/robfig/cron v1.2.0
-	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -2,6 +2,3 @@ github.com/hashicorp/golang-lru v0.6.0 h1:uL2shRDx7RTrOrTCUZEGP/wJUFiUI8QT6E7z5o
 github.com/hashicorp/golang-lru v0.6.0/go.mod h1:iADmTwqILo4mZ8BN3D2Q6+9jd8WM5uGBxy+E8yxSoD4=
 github.com/robfig/cron v1.2.0 h1:ZjScXvvxeQ63Dbyxy76Fj3AT3Ut0aKsyd2/tl3DTMuQ=
 github.com/robfig/cron v1.2.0/go.mod h1:JGuDeoQd7Z6yL4zQhZ3OPEVHB7fL6Ka6skscFHfmt2k=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
-gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

internal/routing/routing.go

@@ -0,0 +1,71 @@
+package routing
+
+import (
+	"net/http"
+	"time"
+)
+
+// CadreFormat specifies how the shot data is formatted.
+type CadreFormat int
+
+const (
+	// CadreFormatANSI represents Terminal ANSI format.
+	CadreFormatANSI = iota
+
+	// CadreFormatHTML represents HTML.
+	CadreFormatHTML
+
+	// CadreFormatPNG represents PNG.
+	CadreFormatPNG
+)
+
+// Cadre contains result of a query execution.
+type Cadre struct {
+	// Body contains the data of Cadre, formatted as Format.
+	Body []byte
+
+	// Format of the shot.
+	Format CadreFormat
+
+	// Expires contains the time of the Cadre expiration,
+	// or 0 if it does not expire.
+	Expires time.Time
+}
+
+// Handler can handle queries and return views.
+type Handler interface {
+	Response(*http.Request) *Cadre
+}
+
+type routeFunc func(*http.Request) bool
+
+type route struct {
+	routeFunc
+	Handler
+}
+
+// Router keeps a routing table, and finds queries handlers, based on its rules.
+type Router struct {
+	rt []route
+}
+
+// Route returns a query handler based on its content.
+func (r *Router) Route(req *http.Request) Handler {
+	for _, re := range r.rt {
+		if re.routeFunc(req) {
+			return re.Handler
+		}
+	}
+	return nil
+}
+
+// AddPath adds route for a static path.
+func (r *Router) AddPath(path string, handler Handler) {
+	r.rt = append(r.rt, route{routePath(path), handler})
+}
+
+func routePath(path string) routeFunc {
+	return routeFunc(func(req *http.Request) bool {
+		return req.URL.Path == path
+	})
+}