Implementation of resolvers for new GraphQL schema

config/config.go

@@ -0,0 +1,64 @@
+package config
+
+import (
+	"context"
+	"encoding/json"
+	"log"
+	"net/http"
+	"os"
+	"sync"
+)
+
+var lock sync.RWMutex
+var config map[string]interface{}
+
+const configFilePath string = "./var/ui.config.json"
+
+func init() {
+	lock.Lock()
+	defer lock.Unlock()
+
+	bytes, err := os.ReadFile(configFilePath)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	if err := json.Unmarshal(bytes, &config); err != nil {
+		log.Fatal(err)
+	}
+}
+
+// Call this function to change the current configuration.
+// `value` must be valid JSON. This This function is thread-safe.
+func UpdateConfig(key, value string, ctx context.Context) error {
+	var v interface{}
+	if err := json.Unmarshal([]byte(value), &v); err != nil {
+		return err
+	}
+
+	lock.Lock()
+	defer lock.Unlock()
+
+	config[key] = v
+	bytes, err := json.Marshal(config)
+	if err != nil {
+		return err
+	}
+
+	if err := os.WriteFile(configFilePath, bytes, 0644); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// http.HandlerFunc compatible function that serves the current configuration as JSON
+func ServeConfig(rw http.ResponseWriter, r *http.Request) {
+	lock.RLock()
+	defer lock.RUnlock()
+
+	rw.Header().Set("Content-Type", "application/json")
+	if err := json.NewEncoder(rw).Encode(config); err != nil {
+		http.Error(rw, err.Error(), http.StatusInternalServerError)
+	}
+}