我正在尝试升级我们的 NestJS GraphQL 订阅服务器以利用graphql-ws而不是当前的subscriptions-transport-ws（如NestJS 文档所建议的）。我将NestJS版本升级到
"@nestjs/core": "^8.0.6",
"@nestjs/graphql": "^9.0.4",
"@nestjs/platform-express": "^8.0.6",
"graphql": "^15.5.3",
"graphql-tools": "^8.2.0",
"apollo-server-express": "^3.3.0",
之后，我将subscriptions选项添加到App.Module：
GraphQLModule.forRoot({
autoSchemaFile: true,
sortSchema: true,
playground: true,
installSubscriptionHandlers: true,
subscriptions: {
'graphql-ws': true
},
}),
但是，当我（在操场上）订阅以前有效的订阅时，我得到：
{
"error": "Could not connect to websocket endpoint ws://localhost:8880/graphql. Please check if the endpoint url is correct."
}
在控制台中我得到：
WebSocket protocol error occured. It was most likely caused due to an unsupported subprotocol "graphql-ws" requested by …