rename listener package to internal/server

socketserver/internal/server/backend.go

@@ -0,0 +1,72 @@
+package server
+
+import (
+	"net/http"
+	"time"
+	"fmt"
+	"net/url"
+	"github.com/pmylund/go-cache"
+	"strconv"
+	"io/ioutil"
+)
+
+var httpClient http.Client
+var backendUrl string
+var responseCache *cache.Cache
+
+func SetupBackend(url string) {
+	httpClient.Timeout = 60 * time.Second
+	backendUrl = url
+	responseCache = cache.New(60 * time.Second, 120 * time.Second)
+}
+
+func getCacheKey(remoteCommand, data string) string {
+	return fmt.Sprintf("%s/%s", remoteCommand, data)
+}
+
+func RequestRemoteDataCached(remoteCommand, data string, auth AuthInfo) (string, error) {
+	cached, ok := responseCache.Get(getCacheKey(remoteCommand, data))
+	if ok {
+		return cached.(string), nil
+	}
+	return RequestRemoteData(remoteCommand, data, auth)
+}
+
+func RequestRemoteData(remoteCommand, data string, auth AuthInfo) (string, error) {
+	destUrl := fmt.Sprintf("%s/%s", backendUrl, remoteCommand)
+	var authKey string
+	if auth.UsernameValidated {
+		authKey = "usernameClaimed"
+	} else {
+		authKey = "username"
+	}
+
+	formData := url.Values{
+		"clientData": []string{data},
+		authKey: []string{auth.TwitchUsername},
+	}
+
+	resp, err := httpClient.PostForm(destUrl, 	formData)
+	if err != nil {
+		return "", err
+	}
+
+	respBytes, err := ioutil.ReadAll(resp.Body)
+	resp.Body.Close()
+	if err != nil {
+		return "", err
+	}
+
+	responseJson := string(respBytes)
+
+	if resp.Header.Get("FFZ-Cache") != "" {
+		durSecs, err := strconv.ParseInt(resp.Header.Get("FFZ-Cache"), 10, 64)
+		if err != nil {
+			return "", fmt.Errorf("The RPC server returned a non-integer cache duration: %v", err)
+		}
+		duration := time.Duration(durSecs) * time.Second
+		responseCache.Set(getCacheKey(remoteCommand, data), responseJson, duration)
+	}
+
+	return responseJson, nil
+}