Add more error handling and mutex guards

sharedlibrary/collections.go

@@ -47,7 +47,10 @@ func GetCollection(serverName *C.char, databaseId *C.char, collectionId *C.char)
 		return C.CString("")
 	}
 
-	collectionJson, _ := json.Marshal(collection)
+	collectionJson, err := json.Marshal(collection)
+	if err != nil {
+		return C.CString("")
+	}
 	return C.CString(string(collectionJson))
 }
 
@@ -67,7 +70,10 @@ func GetAllCollections(serverName *C.char, databaseId *C.char) *C.char {
 		return C.CString("")
 	}
 
-	collectionsJson, _ := json.Marshal(collections)
+	collectionsJson, err := json.Marshal(collections)
+	if err != nil {
+		return C.CString("")
+	}
 	return C.CString(string(collectionsJson))
 }
 

sharedlibrary/databases.go

@@ -45,7 +45,10 @@ func GetDatabase(serverName *C.char, databaseId *C.char) *C.char {
 		return C.CString("")
 	}
 
-	databaseJson, _ := json.Marshal(database)
+	databaseJson, err := json.Marshal(database)
+	if err != nil {
+		return C.CString("")
+	}
 	return C.CString(string(databaseJson))
 }
 

sharedlibrary/documents.go

@@ -49,7 +49,10 @@ func GetDocument(serverName *C.char, databaseId *C.char, collectionId *C.char, d
 		return C.CString("")
 	}
 
-	documentJson, _ := json.Marshal(document)
+	documentJson, err := json.Marshal(document)
+	if err != nil {
+		return C.CString("")
+	}
 	return C.CString(string(documentJson))
 }
 
@@ -70,7 +73,10 @@ func GetAllDocuments(serverName *C.char, databaseId *C.char, collectionId *C.cha
 		return C.CString("")
 	}
 
-	documentsJson, _ := json.Marshal(documents)
+	documentsJson, err := json.Marshal(documents)
+	if err != nil {
+		return C.CString("")
+	}
 	return C.CString(string(documentsJson))
 }
 

sharedlibrary/shared.go

@@ -14,7 +14,7 @@ type ServerInstance struct {
 }
 
 var serverInstances map[string]*ServerInstance
-var mutex sync.RWMutex
+var mutex sync.Mutex
 
 const (
 	ResponseSuccess = 0
@@ -32,8 +32,8 @@ const (
 )
 
 func getInstance(serverName string) (*ServerInstance, bool) {
-	mutex.RLock()
-	defer mutex.RUnlock()
+	mutex.Lock()
+	defer mutex.Unlock()
 
 	if serverInstances == nil {
 		serverInstances = make(map[string]*ServerInstance)