Start abstracting template stuff

This is for #32.

This adds a starting framework for loading, caching, and executing
templates on the server and the client.  Currently only the server uses
this functionality.

common/templates.go

@@ -0,0 +1,89 @@
+package common
+
+import (
+	"fmt"
+	html "html/template"
+	"net/http"
+	"strings"
+	text "text/template"
+)
+
+// Holds the server's templates
+var serverTemplates map[string]*html.Template
+
+// Holds the client's chat templates
+var chatTemplates map[string]*text.Template
+
+var isServer bool = false
+
+// keys and files to load for that template
+var serverTemplateDefs map[string][]string = map[string][]string{
+	"pin":  []string{"./static/base.html", "./static/thedoor.html"},
+	"main": []string{"./static/base.html", "./static/main.html"},
+	"help": []string{"./static/base.html", "./static/help.html"},
+}
+
+var chatTemplateDefs map[string]string = map[string]string{
+	fmt.Sprint(DTInvalid, 0): "wot",
+
+	fmt.Sprint(DTChat, MsgChat): `<span>{{.Badge}} <span class="name" style="color:{{.Color}}">{{.From}}` +
+		`</span><b>:</b> <span class="msg">{{.Message}}</span></span>`,
+	fmt.Sprint(DTChat, MsgAction): `<span style="color:{{.Color}}"><span class="name">{{.From}}` +
+		`</span> <span class="cmdme">{{.Message}}</span></span>`,
+}
+
+// Called from the server
+func InitTemplates() error {
+	isServer = true
+	serverTemplates = make(map[string]*html.Template)
+	chatTemplates = make(map[string]*text.Template)
+
+	// Parse server templates
+	for key, files := range serverTemplateDefs {
+		t, err := html.ParseFiles(files...)
+		if err != nil {
+			return fmt.Errorf("Unable to parse templates for %s: %v", key, err)
+		}
+
+		serverTemplates[key] = t
+	}
+
+	// Parse client templates
+	//for key, def := range chatTemplateDefs {
+	//	t := text.New(key)
+	//	err, _ := t.Parse(def)
+	//	if err != nil {
+	//		return fmt.Errorf("Unabel to parse chat template %q: %v", key, err)
+	//	}
+
+	//	chatTemplates[key] = t
+	//}
+
+	return nil
+}
+
+// TODO
+func LoadChatTemplates() error {
+	return nil
+}
+
+func ExecuteChatTemplate(typeA, typeB int, data interface{}) (string, error) {
+	key := fmt.Sprint(typeA, typeB)
+	t := chatTemplates[key]
+	builder := &strings.Builder{}
+
+	if err := t.Execute(builder, data); err != nil {
+		return "", err
+	}
+
+	return builder.String(), nil
+}
+
+func ExecuteServerTemplate(w http.ResponseWriter, key string, data interface{}) error {
+	t, ok := serverTemplates[key]
+	if !ok {
+		return fmt.Errorf("Template with the key %q does not exist", key)
+	}
+
+	return t.Execute(w, data)
+}

handlers.go

@@ -3,7 +3,6 @@ package main
 import (
 	"encoding/json"
 	"fmt"
-	"html/template"
 	"io"
 	"net/http"
 	"path/filepath"
@@ -223,12 +222,6 @@ func checkRoomAccess(w http.ResponseWriter, r *http.Request) bool {
 }
 
 func handlePinTemplate(w http.ResponseWriter, r *http.Request, errorMessage string) {
-	t, err := template.ParseFiles("./static/base.html", "./static/thedoor.html")
-	if err != nil {
-		common.LogErrorf("Error parsing template file: %v", err)
-		return
-	}
-
 	type Data struct {
 		Title      string
 		SubmitText string
@@ -245,19 +238,13 @@ func handlePinTemplate(w http.ResponseWriter, r *http.Request, errorMessage stri
 		Notice:     errorMessage,
 	}
 
-	err = t.Execute(w, data)
+	err := common.ExecuteServerTemplate(w, "pin", data)
 	if err != nil {
 		common.LogErrorf("Error executing file, %v", err)
 	}
 }
 
 func handleHelpTemplate(w http.ResponseWriter, r *http.Request) {
-	t, err := template.ParseFiles("./static/base.html", "./static/help.html")
-	if err != nil {
-		common.LogErrorf("Error parsing template file, %v\n", err)
-		return
-	}
-
 	type Data struct {
 		Title         string
 		Commands      map[string]string
@@ -278,7 +265,7 @@ func handleHelpTemplate(w http.ResponseWriter, r *http.Request) {
 		data.AdminCommands = getHelp(common.CmdlAdmin)
 	}
 
-	err = t.Execute(w, data)
+	err := common.ExecuteServerTemplate(w, "help", data)
 	if err != nil {
 		common.LogErrorf("Error executing file, %v", err)
 	}
@@ -314,12 +301,6 @@ func handleIndexTemplate(w http.ResponseWriter, r *http.Request) {
 		common.LogDebugln("Granted access")
 	}
 
-	t, err := template.ParseFiles("./static/base.html", "./static/main.html")
-	if err != nil {
-		common.LogErrorf("Error parsing template file, %v\n", err)
-		return
-	}
-
 	type Data struct {
 		Video, Chat         bool
 		MessageHistoryCount int
@@ -347,7 +328,7 @@ func handleIndexTemplate(w http.ResponseWriter, r *http.Request) {
 		w.Header().Set("Cache-Control", "no-cache, must-revalidate")
 	}
 
-	err = t.Execute(w, data)
+	err := common.ExecuteServerTemplate(w, "main", data)
 	if err != nil {
 		common.LogErrorf("Error executing file, %v", err)
 	}

main.go

@@ -51,6 +51,11 @@ func main() {
 		os.Exit(1)
 	}
 
+	if err := common.InitTemplates(); err != nil {
+		common.LogErrorln(err)
+		os.Exit(1)
+	}
+
 	exit := make(chan bool)
 	go handleInterrupt(exit)