From d5148efc41c2ed82e4c22a15390df78d7b46c391 Mon Sep 17 00:00:00 2001 From: Tom Andrade Date: Sun, 6 Oct 2019 13:40:14 +0200 Subject: [PATCH] Use structs to hold configuration data instead of loose variables --- main.go | 229 ++++++++++++++++++++++++++++---------------------------- 1 file changed, 116 insertions(+), 113 deletions(-) diff --git a/main.go b/main.go index 15ecfe0..2d9929f 100644 --- a/main.go +++ b/main.go @@ -22,17 +22,19 @@ import ( "github.com/patrickmn/go-cache" ) -const letterBytes = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789" // Base strings for randStringBytesMaskImprSrc -const ( - letterIdxBits = 6 // 6 bits to represent a letter index - letterIdxMask = 1< 65535 || cfg.port < 1 { + log.Fatalln("Invalid port number") + } + if cfg.path != "" && !strings.HasSuffix(cfg.path, "/") { + cfg.path = cfg.path + "/" + } + + if cfg.port != 80 && cfg.proto == "http" { + cfg.hostSuf = ":" + strconv.Itoa(cfg.port) + "/" + } else if cfg.port != 443 && cfg.proto == "https" { + cfg.hostSuf = ":" + strconv.Itoa(cfg.port) + "/" + } else if cfg.port == 443 || cfg.port == 80 { + cfg.hostSuf = "/" + } + + ip := net.ParseIP(cfg.addr) + if ip != nil { + cfg.listenAddr = ip.String() + ":" + strconv.Itoa(cfg.port) + } else { + if govalidator.IsDNSName(cfg.addr) { + cfg.listenAddr = cfg.addr + ":" + strconv.Itoa(cfg.port) + } else { + log.Fatalln("Invalid ip address") + } + } + + if !govalidator.IsDNSName(cfg.domain) { + log.Fatalln("Invalid domain address") + } + + cfg.templates = template.Must(template.ParseFiles("templates/response.html")) +} + +func (c config) index(w http.ResponseWriter, r *http.Request) { b := body{ HasForm: true, Line1: "Welcome to Short, the simple URL shortener,", Line2: "Type an URL below to shorten it", } - t.Execute(w, b) + c.templates.Execute(w, b) } // get executes the GET command @@ -71,7 +137,7 @@ func set(key, suffix string) { // redirect reads the key from the requests url (GET /key) searches the // kv database for it and if found redirects the user to value, if not // found return a 404. -func redirect(w http.ResponseWriter, r *http.Request, path string) { +func (c config) redirect(w http.ResponseWriter, r *http.Request) { vals := mux.Vars(r) key := vals["key"] b := body{ @@ -83,15 +149,15 @@ func redirect(w http.ResponseWriter, r *http.Request, path string) { Line1: "Boo, looks like this ghost stole this page!", Line2: "But you can type an URL below to shorten it", } - if path != "" { - key = strings.Replace(key, path, "", 1) + if c.path != "" { + key = strings.Replace(key, c.path, "", 1) } rgx, _ := regexp.Compile("[a-zA-Z0-9]+") key = rgx.FindString(key) key, status := get(key) if !status { w.WriteHeader(http.StatusNotFound) - t.Execute(w, b) + c.templates.Execute(w, b) return } u, _ := url.Parse(key) @@ -106,7 +172,7 @@ func redirect(w http.ResponseWriter, r *http.Request, path string) { // unique on the kv database and if not unique regenerates it and checks again, // then if writes the kv pair suffix, url to the database and return the // shortened url to the user -func shortner(w http.ResponseWriter, r *http.Request, proto, domain, hostSuf, path string, urlSize int) { +func (c config) shortner(w http.ResponseWriter, r *http.Request) { if !govalidator.IsURL(r.FormValue("url")) { b := body{ FullHeader: true, @@ -118,26 +184,26 @@ func shortner(w http.ResponseWriter, r *http.Request, proto, domain, hostSuf, pa Line2: "But you can type an URL below to shorten it", } w.WriteHeader(http.StatusBadRequest) - t.Execute(w, b) + c.templates.Execute(w, b) return } u, _ := url.Parse(r.FormValue("url")) - suffix := randStringBytesMaskImprSrc(urlSize) + suffix := randStringBytesMaskImprSrc(c.urlSize) for { _, status := get(suffix) if !status { break } - suffix = randStringBytesMaskImprSrc(urlSize) + suffix = randStringBytesMaskImprSrc(c.urlSize) } set(u.String(), suffix) - shortend := proto + "://" + domain + hostSuf + path + suffix + shortend := c.proto + "://" + c.domain + c.hostSuf + c.path + suffix b := body{ IsLink: true, Line1: shortend, } - t.Execute(w, b) + c.templates.Execute(w, b) } // randStringBytesMaskImprSrc Generate random string of n size @@ -160,7 +226,7 @@ func randStringBytesMaskImprSrc(n int) string { // internalError receives a http.ResponseWriter, msg and error and // return a internal error page with http code 500 to the user -func internalError(w http.ResponseWriter, msg string, err error) { +func (c config) internalError(w http.ResponseWriter, msg string, err error) { b := body{ FullHeader: true, IsGhost: true, @@ -172,11 +238,11 @@ func internalError(w http.ResponseWriter, msg string, err error) { } log.Println(err) w.WriteHeader(http.StatusInternalServerError) - t.Execute(w, b) + c.templates.Execute(w, b) } // itemsCount returns the number of kv pairs on the in meomry database -func itemsCount(w http.ResponseWriter, r *http.Request) { +func (c config) itemsCount(w http.ResponseWriter, r *http.Request) { w.Write( []byte( strconv.Itoa( @@ -187,12 +253,12 @@ func itemsCount(w http.ResponseWriter, r *http.Request) { } // itemsDump returns a json with all the kv pairs on the in memory database -func itemsDump(w http.ResponseWriter, r *http.Request) { +func (c config) itemsDump(w http.ResponseWriter, r *http.Request) { dumpObj, err := json.Marshal( pool.Items(), ) if err != nil { - internalError(w, "Unable to dump key value db: ", err) + c.internalError(w, "Unable to dump key value db: ", err) } w.Write( []byte(dumpObj), @@ -200,129 +266,66 @@ func itemsDump(w http.ResponseWriter, r *http.Request) { } // itemsFromFile loads kv pairs from the dumpFile json to the in memory database -func itemsFromFile(w http.ResponseWriter, r *http.Request, dumpFile string) { - jsonFile, err := ioutil.ReadFile(dumpFile) +func (c config) itemsFromFile(w http.ResponseWriter, r *http.Request) { + jsonFile, err := ioutil.ReadFile(c.dumpFile) var dumpObj map[string]cache.Item json.Unmarshal([]byte(jsonFile), &dumpObj) if err != nil { - internalError(w, "Cannot open file "+dumpFile+": ", err) + c.internalError(w, "Cannot open file "+c.dumpFile+": ", err) return } pool = cache.NewFrom(240*time.Hour, 1*time.Hour, dumpObj) b := body{ Line1: "Imported " + strconv.Itoa(len(dumpObj)) + " items to the DB", } - t.Execute(w, b) + c.templates.Execute(w, b) } // itemsFromPost loads kv pairs from a json POST to the in memory database -func itemsFromPost(w http.ResponseWriter, r *http.Request) { +func (c config) itemsFromPost(w http.ResponseWriter, r *http.Request) { decoder := json.NewDecoder(r.Body) var dumpObj map[string]cache.Item err := decoder.Decode(&dumpObj) if err != nil { - internalError(w, "Cannot parse JSON: ", err) + c.internalError(w, "Cannot parse JSON: ", err) return } pool = cache.NewFrom(240*time.Hour, 1*time.Hour, dumpObj) b := body{ Line1: "Imported " + strconv.Itoa(len(dumpObj)) + " items to the DB", } - t.Execute(w, b) + c.templates.Execute(w, b) } // itemsDumpToFile dumps the kv pairs from the in memory database to the dumpFile -func itemsDumpToFile(w http.ResponseWriter, r *http.Request, dumpFile string) { +func (c config) itemsDumpToFile(w http.ResponseWriter, r *http.Request) { dumpObj, _ := json.Marshal( pool.Items(), ) - err := ioutil.WriteFile(dumpFile, dumpObj, 0644) + err := ioutil.WriteFile(c.dumpFile, dumpObj, 0644) if err != nil { - internalError(w, "Failed to open json file: ", err) + c.internalError(w, "Failed to open json file: ", err) return } b := body{ - Line1: "Imported " + "Dump writen to: " + dumpFile, + Line1: "Imported " + "Dump writen to: " + c.dumpFile, } - t.Execute(w, b) - + c.templates.Execute(w, b) } func main() { - var hostSuf string - var listenAddr string - - addr := flag.String("addr", "localhost", "Address to listen for connections") - domain := flag.String("domain", "localhost", "Domain to write to the URLs") - dumpFile := flag.String("dump", "urls.json", "Path to the file to dump the kv db") - path := flag.String("path", "", "Path to the base URL (https://localhost/PATH/... remember to append a / at the end") - port := flag.Int("port", 8080, "Port to listen for connections") - proto := flag.String("proto", "https", "proto to the base URL (HTTPS://localhost/path/... no real https here just to set the url (for like a proxy offloading https") - urlSize := flag.Int("urlsize", 10, "Define the size of the shortened String, default 10") - version := flag.Bool("v", false, "prints current version") - flag.Parse() - if *version { - log.SetFlags(0) - log.Println(appVersion) - os.Exit(0) - } - - if *port > 65535 || *port < 1 { - log.Fatalln("Invalid port number") - } - if *path != "" && !strings.HasSuffix(*path, "/") { - *path = *path + "/" - } - if *port != 80 && *proto == "http" { - hostSuf = ":" + strconv.Itoa(*port) + "/" - } else if *port != 443 && *proto == "https" { - hostSuf = ":" + strconv.Itoa(*port) + "/" - } else if *port == 443 || *port == 80 { - hostSuf = "/" - } - ip := net.ParseIP(*addr) - if ip != nil { - listenAddr = ip.String() + ":" + strconv.Itoa(*port) - } else { - if govalidator.IsDNSName(*addr) { - listenAddr = *addr + ":" + strconv.Itoa(*port) - } else { - log.Fatalln("Invalid ip address") - } - } - - if !govalidator.IsDNSName(*domain) { - log.Fatalln("Invalid domain address") - } r := mux.NewRouter() - r.HandleFunc("/", index).Methods("GET") + r.HandleFunc("/", cfg.index).Methods("GET") + r.HandleFunc("/", cfg.shortner).Methods("POST") + r.HandleFunc("/{key}", cfg.redirect).Methods("GET") + r.HandleFunc("/v1/dumpToFile", cfg.itemsDumpToFile).Methods("GET") + r.HandleFunc("/v1/fromFile", cfg.itemsFromFile).Methods("GET") + r.HandleFunc("/v1/count", cfg.itemsCount).Methods("GET") + r.HandleFunc("/v1/dump", cfg.itemsDump).Methods("GET") + r.HandleFunc("/v1/fromPost", cfg.itemsFromPost).Methods("POST") - r.HandleFunc("/", - func(w http.ResponseWriter, r *http.Request) { - shortner(w, r, *proto, *domain, hostSuf, *path, *urlSize) - }).Methods("POST") - - r.HandleFunc("/{key}", - func(w http.ResponseWriter, r *http.Request) { - redirect(w, r, *path) - }).Methods("GET") - - r.HandleFunc("/v1/dumpToFile", - func(w http.ResponseWriter, r *http.Request) { - itemsDumpToFile(w, r, *dumpFile) - }).Methods("GET") - - r.HandleFunc("/v1/fromFile", - func(w http.ResponseWriter, r *http.Request) { - itemsFromFile(w, r, *dumpFile) - }).Methods("GET") - - r.HandleFunc("/v1/count", itemsCount).Methods("GET") - r.HandleFunc("/v1/dump", itemsDump).Methods("GET") - r.HandleFunc("/v1/fromPost", itemsFromPost).Methods("POST") - - log.Printf("Domain: %s, URL Proto: %s, Listen Address: %s\n", *domain, *proto, *addr) - log.Fatal(http.ListenAndServe(listenAddr, handlers.CombinedLoggingHandler(os.Stdout, r))) + log.Printf("Domain: %s, URL Proto: %s, Listen Address: %s\n", cfg.domain, cfg.proto, cfg.listenAddr) + log.Fatal(http.ListenAndServe(cfg.listenAddr, handlers.CombinedLoggingHandler(os.Stdout, r))) }