From 058c616667aa4aa0506a7fd206c892c686e24f0f Mon Sep 17 00:00:00 2001
From: Yasen Pramatarov <yasen@lindeas.com>
Date: Wed, 16 Oct 2024 09:45:07 +0300
Subject: [PATCH] Adds a health check

---
 jilo-server.conf |  5 +++++
 main.go          | 34 +++++++++++++++++++++++++++++-----
 2 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/jilo-server.conf b/jilo-server.conf
index 1bce772..1341c24 100644
--- a/jilo-server.conf
+++ b/jilo-server.conf
@@ -1,2 +1,7 @@
 # database location
 database_path: "./jilo-server.db"
+
+# health check
+health_check_enabled: true
+health_check_port: 8080
+health_check_endpoint: "/health"
diff --git a/main.go b/main.go
index d685393..346494c 100644
--- a/main.go
+++ b/main.go
@@ -18,17 +18,23 @@ import (
 
 // Structures
 type Agent struct {
-    ID                  int
-    URL                 string
-    Secret              string
-    CheckPeriod         int
+    ID              int
+    URL             string
+    Secret          string
+    CheckPeriod     int
 }
 type Config struct {
-    DatabasePath        string      `yaml:"database_path"`
+    DatabasePath            string      `yaml:"database_path"`
+    HealthCheckEnabled      bool        `yaml:"health_check_enabled"`
+    HealthCheckPort         int         `yaml:"health_check_port"`
+    HealthCheckEndpoint     string      `yaml:"health_check_endpoint"`
 }
 
 var defaultConfig = Config {
     DatabasePath: "./jilo-server.db",
+    HealthCheckEnabled: false,
+    HealthCheckPort: 8080,
+    HealthCheckEndpoint: "/health",
 }
 
 // Loading the config file
@@ -50,6 +56,19 @@ func readConfig(filePath string) Config {
     return config
 }
 
+// Start the health check
+func startHealthCheckServer(port int, endpoint string) {
+    http.HandleFunc(endpoint, func(w http.ResponseWriter, r *http.Request) {
+        w.WriteHeader(http.StatusOK)
+        w.Write([]byte("Jilo Server is running"))
+    })
+
+    address := fmt.Sprintf(":%d", port)
+
+    log.Printf("Starting health check server on %s%s", address, endpoint)
+    go http.ListenAndServe(address, nil)
+}
+
 // Database initialization
 func setupDatabase(dbPath string, initDB bool) (*sql.DB, error) {
 
@@ -259,6 +278,11 @@ func main() {
     log.Printf("Using config file %s", finalConfigPath)
     config := readConfig(finalConfigPath)
 
+    // Start the health check, if it's enabled in the config file
+    if config.HealthCheckEnabled {
+        startHealthCheckServer(config.HealthCheckPort, config.HealthCheckEndpoint)
+    }
+
     // Connect to or setup the database
     log.Println("Initializing the database...")
     db, err := setupDatabase(config.DatabasePath, *initDB)