feat: add logging

Signed-off-by: Smuu <18609909+Smuu@users.noreply.github.com>

README.md

@@ -1 +1,5 @@
-# autoscale-proxy
+# autoscale-proxy
+
+## ToDo
+
+- use internal services instead of domain names

main.go

@@ -3,10 +3,24 @@ package main
 import (
 	"bytes"
 	"io"
+	"log"
 	"net/http"
+	"os"
 	"strings"
 )
 
+var (
+	debugLog *log.Logger
+	infoLog  *log.Logger
+	errorLog *log.Logger
+)
+
+func init() {
+	debugLog = log.New(os.Stdout, "DEBUG: ", log.Ldate|log.Ltime|log.Lshortfile)
+	infoLog = log.New(os.Stdout, "INFO: ", log.Ldate|log.Ltime|log.Lshortfile)
+	errorLog = log.New(os.Stderr, "ERROR: ", log.Ldate|log.Ltime|log.Lshortfile)
+}
+
 func replaceDomainInResponse(originalSubdomain, replaceSubdomain, originalDomain string, buffer *bytes.Buffer) {
 	body := buffer.String()
 	fullReplace := replaceSubdomain + "." + "lunaroasis.net" // We know that statescale and snapscale are under this domain
@@ -43,8 +57,10 @@ func proxyRequest(fullSubdomain, path string, buffer *bytes.Buffer, r *http.Requ
 }
 
 func handleRequest(w http.ResponseWriter, r *http.Request) {
+	infoLog.Printf("Received request from %s", r.Host)
 	hostParts := strings.Split(r.Host, ".")
 	if len(hostParts) < 3 {
+		errorLog.Printf("Invalid domain: %s", r.Host)
 		http.Error(w, "Invalid domain", http.StatusBadRequest)
 		return
 	}
@@ -55,9 +71,14 @@ func handleRequest(w http.ResponseWriter, r *http.Request) {
 	buffer := new(bytes.Buffer)
 	backupBuffer := new(bytes.Buffer)
 
+	debugLog.Printf("Proxying request to %s", subdomain+".statescale")
 	statusCode, headers, err := proxyRequest(subdomain+".statescale", r.RequestURI, buffer, r)
+	debugLog.Printf("Received status code %d", statusCode)
 	if err != nil || statusCode >= 400 {
+		debugLog.Printf("Proxying request to %s", subdomain+".snapscale")
 		backupStatusCode, backupHeaders, _ := proxyRequest(subdomain+".snapscale", r.RequestURI, backupBuffer, r)
+		debugLog.Printf("Received status code %d", backupStatusCode)
+
 		replaceDomainInResponse(subdomain, subdomain+".snapscale", originalDomain, backupBuffer)
 
 		for key, value := range backupHeaders {
@@ -77,6 +98,7 @@ func handleRequest(w http.ResponseWriter, r *http.Request) {
 }
 
 func main() {
+	infoLog.Println("Starting server on :8080")
 	http.HandleFunc("/", handleRequest)
 	http.ListenAndServe(":8080", nil)
 }