Serve html from golang server via template

.gitignore

@@ -1,3 +1,4 @@
 *.sqlite3
 *.sqlite3-journal
 .DS_Store
+.vscode

server.go

@@ -4,6 +4,7 @@ import (
 	"database/sql"
 	"encoding/json"
 	"fmt"
+	"html/template"
 	"log"
 	"net/http"
 
@@ -17,6 +18,7 @@ const (
 
 var (
 	db                *sql.DB
+	indexHtmlTemplate *template.Template
 )
 
 type ChoicesPost struct {
@@ -60,6 +62,22 @@ func initDatabase() {
 	}
 }
 
+func prepareStaticContent() {
+	var err error
+	indexHtmlTemplate, err = template.ParseFiles("./static/index.html")
+	if err != nil {
+		log.Fatalf("[!] Could not parse index.html template, error: %s\n", err)
+	}
+}
+
+func handleGetRoot(w http.ResponseWriter, r *http.Request) {
+	err := indexHtmlTemplate.Execute(w, nil)
+	if err != nil {
+		log.Printf("[!] Could not execute index.html template, error: %s\n", err)
+		http.Error(w, "Error rendering template", http.StatusInternalServerError)
+	}
+}
+
 func handleGetPing(w http.ResponseWriter, r *http.Request) {
 	log.Printf("[*] Received request %v %v\n", r.Method, r.URL)
 	fmt.Fprintf(w, "PONG\n")
@@ -86,17 +104,30 @@ func handlePostSubmit(w http.ResponseWriter, r *http.Request) {
 		log.Printf("[!] Could not marshal choices, error: %s\n", err)
 	}
 
+	tx, err := db.Begin()
+	if err != nil {
+		log.Printf("[!] Could not begin database transaction, error: %s\n", err)
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+
 	const query = `
 		INSERT INTO choices (pollid, username, choices)
 		VALUES (?, ?, ?);
 	`
 
-	_, err = db.Exec(query, choicesPost.PollId, choicesPost.Username, string(choicesJson))
+	_, err = tx.Exec(query, choicesPost.PollId, choicesPost.Username, string(choicesJson))
 	if err != nil {
 		log.Printf("[!] Could not insert choices into database, error: %s\n", err)
+		tx.Rollback()
+		w.WriteHeader(http.StatusBadRequest)
+		return
 	}
 
-	log.Printf("[*] Persisted choices for %s to database\n", "DUMMY USERNAME")
+	tx.Commit()
+
+	log.Printf("[*] Persisted choices for poll %d, username %s to database\n",
+		choicesPost.PollId, choicesPost.Username)
 
 	w.WriteHeader(http.StatusOK)
 }
@@ -112,11 +143,18 @@ func main() {
 	initDatabase()
 	defer db.Close()
 
+	prepareStaticContent()
+
 	http.HandleFunc(
 		"GET /api/ping",
 		handleGetPing,
 	)
 
+	http.HandleFunc(
+		"GET /",
+		handleGetRoot,
+	)
+
 	http.HandleFunc(
 		"POST /api/submit",
 		handlePostSubmit,

static/index.html

@@ -54,7 +54,84 @@
         <input id="submit-name" type="text" placeholder="Enter your name" />
         <button id="submit-btn" type="submit" onclick="submit">Submit</button>
     </div>
-    <script src="index.js"></script>
+    <script>
+        // Days of the week
+        const daysOfWeek = ["Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"];
+
+        // Select the calendar container
+        const calendar = document.getElementById("calendar");
+
+        // Create the weekly calendar
+        daysOfWeek.forEach((day) => {
+            // Create a column for each day
+            const dayColumn = document.createElement("div");
+            dayColumn.classList.add("day-column");
+
+            // Add a header for the day
+            const dayHeader = document.createElement("div");
+            dayHeader.classList.add("day-header");
+            dayHeader.textContent = day;
+            dayColumn.appendChild(dayHeader);
+
+            // Add hourly blocks for each day
+            for (let hour = 0; hour < 24; hour++) {
+                const hourBlock = document.createElement("div");
+                hourBlock.classList.add("hour-block");
+                hourBlock.textContent = `${hour}:00`;
+
+                // Add a click event listener to toggle color
+                hourBlock.addEventListener("click", () => {
+                    hourBlock.classList.toggle("clicked");
+                });
+
+                dayColumn.appendChild(hourBlock);
+            }
+
+            // Append the day column to the calendar
+            calendar.appendChild(dayColumn);
+        });
+
+        const submitName = document.getElementById("submit-name")
+        const submitBtn = document.getElementById("submit-btn")
+
+        submitBtn.onclick = function () {
+            if (submitName.value == "") {
+                console.log("Submitter name is missing.")
+                return
+            }
+
+            const days = calendar.children
+            const choices = Array.from(days).map(
+                day => Array.from(day.children).slice(1, 25).map(
+                    hour => hour.classList.contains("clicked")))
+            console.log(`Submitting dates for ${submitName.value}`)
+            console.log(JSON.stringify(choices))
+
+            const url = "http://localhost:8080/api/submit";
+
+            fetch(url, {
+                method: "POST", // Specify the HTTP method
+                headers: {
+                    "Content-Type": "application/json", // Inform the server about the data format
+                },
+                body: JSON.stringify({pollId: 1, username: submitName.value, choices: choices}), // Convert the data to JSON string
+            })
+            /*
+                .then(response => {
+                    if (!response.ok) {
+                        throw new Error('Network response was not ok ' + response.statusText);
+                    }
+                    return response.json(); // Parse the JSON response
+                })
+                .then(data => {
+                    console.log('Success:', data); // Handle the response data
+                })
+                .catch(error => {
+                    console.error('Error:', error); // Handle errors
+                });
+            */
+        }
+    </script>
 </body>
 
 </html>