Make Port and http/https configurable for the test container

It introduces env vars:

* HTTP_PORT: choose a port to serve. If not set, uses 8080
* HTTPS_PORT: choose to serve HTTPS and on which port
* HTTPS_CERT_PATH: Path to the cert to use when serving HTTPS
* HTTPS_KEY_PATH: Path to the ssl key to use when serving HTTPS

Change-Id: I5078ba0345999dadd7d3850f07c538a617c54e46
Signed-off-by: Antoni Segura Puimedon <celebdor@gmail.com>

test_container/server.go

@@ -1,21 +1,46 @@
 package main
 
 import (
-        "fmt"
-        "log"
-        "net/http"
-        "os"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"strings"
 )
 
 func handler(w http.ResponseWriter, r *http.Request) {
-        hostname, err := os.Hostname()
-        log.Println("Received request")
-        if err == nil {
-                fmt.Fprintf(w, "%s: HELLO! I AM ALIVE!!!\n", hostname)
-        }
+	hostname, err := os.Hostname()
+	log.Println("Received request")
+	if err == nil {
+		fmt.Fprintf(w, "%s: HELLO! I AM ALIVE!!!\n", hostname)
+	}
 }
 
 func main() {
-    http.HandleFunc("/", handler)
-    log.Fatal(http.ListenAndServe(":8080", nil))
+	http.HandleFunc("/", handler)
+
+	httpsPort, httpsPortPresent := os.LookupEnv("HTTPS_PORT")
+
+	var port string
+	if httpsPortPresent {
+		port = ":" + strings.TrimSpace(httpsPort)
+
+		cert, certPresent := os.LookupEnv("HTTPS_CERT_PATH")
+		key, keyPresent := os.LookupEnv("HTTPS_KEY_PATH")
+
+		if !certPresent || !keyPresent {
+			log.Fatal("HTTPS_PORT configured but missing HTTPS_CERT_PATH and/or HTTPS_KEY_PATH")
+		}
+
+		log.Fatal(http.ListenAndServeTLS(port, cert, key, nil))
+	} else {
+		httpPort, confPresent := os.LookupEnv("HTTP_PORT")
+		if confPresent {
+			port = ":" + strings.TrimSpace(httpPort)
+		} else {
+			port = ":8080"
+		}
+
+		log.Fatal(http.ListenAndServe(port, nil))
+	}
 }