如何使用 apollo ios 客户端实现 graphql 订阅
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【中文标题】如何使用 apollo ios 客户端实现 graphql 订阅【英文标题】:How to implement graphql subscription using apollo ios client 【发布时间】:2019-01-14 03:58:56 【问题描述】:我正在尝试使用 apollo ios 客户端实现 graphql 订阅。但由于缺乏文档示例而无法弄清楚。 阿波罗文档中给出的示例是:
let apollo: ApolloClient =
let configuration = URLSessionConfiguration.default
// Add additional headers as needed
configuration.httpAdditionalHeaders = ["Authorization": "Bearer <token>"] // Replace `<token>`
let url = URL(string: "http://localhost:8080/graphql")!
return ApolloClient(networkTransport: HTTPNetworkTransport(url: url, configuration: configuration))
()
APOLLO IOS GUIDE: Creating a client
【问题讨论】:
【参考方案1】:按照以下步骤在 apollo ios graphql 客户端中实现订阅。
使用 cocoapods:
pod 'Apollo'
pod 'Apollo/WebSocket'
pod install
创建客户端以支持订阅和身份验证。在AppDelegate.swift
中添加以下代码:
-
Websocket - 我们必须使用
WebSocketTransport
和URLRequest
身份验证 - 我们必须将连接参数connectingPayload
中的身份验证参数传递给服务器。对于 http,我们在问题 sn-p 中提到的标头中传递它。
SplitNetworkTransport
- 结合 http
和 websocket
来创建客户端。我们必须使用httpNetworkTransport
和webSocketNetworkTransport
lazy var apollo: ApolloClient =
let authPayloads = [
"Authorization": "Bearer "
]
let configuration = URLSessionConfiguration.default
configuration.httpAdditionalHeaders = authPayloads
let map: GraphQLMap = authPayloads
let wsEndpointURL = URL(string: "ws://localhost:8080/subscriptions")!
let endpointURL = URL(string: "http://localhost:8080/api")!
let websocket = WebSocketTransport(request: URLRequest(url: wsEndpointURL), connectingPayload: map)
let splitNetworkTransport = SplitNetworkTransport(
httpNetworkTransport: HTTPNetworkTransport(
url: endpointURL,
configuration: configuration
),
webSocketNetworkTransport: websocket
)
return ApolloClient(networkTransport: splitNetworkTransport)
()
【讨论】:
从哪里获得 wsEndpointURL?下一步我需要做什么来更新 UI? 你能帮帮我吗【参考方案2】:我快到了。我因在 Websocket 升级中没有正确的标头而被拒绝。我最终不得不直接在URLRequest
对象上设置它们。
var apollo: ApolloClient?
let authHeaders = ["X-Hasura-Access-Key": "<my_Key>", "Content-Type": "application/json"]
let configuration = URLSessionConfiguration.default
// Add additional headers as needed
configuration.httpAdditionalHeaders = authHeaders
//The string to my graph QL Server run by Hasure on AWS RDS.
let graphQLEndpoint = "http://<my_host>/v1alpha1/graphql"
let graphQLSubscriptionEndpoint = "ws://<my_host>/v1alpha1/graphql"
//Take my Ec2 Server string and make a URL for the graph QL and subscriptions
guard let httpURL = URL(string: graphQLEndpoint), let webSocketURL = URL(string: graphQLSubscriptionEndpoint) else
return nil
let httpTransport = HTTPNetworkTransport(url: httpURL, configuration: configuration, sendOperationIdentifiers: false)
var request = URLRequest(url: webSocketURL)
request.setValue("<my_key>", forHTTPHeaderField: "X-Hasura-Access-Key")
request.setValue("application/json", forHTTPHeaderField: "Content-Type")
let webSocketTransport = WebSocketTransport(request: request, sendOperationIdentifiers: false, connectingPayload: nil)
let splitTransport = SplitNetworkTransport(httpNetworkTransport: httpTransport, webSocketNetworkTransport: webSocketTransport)
//Initalize the APolloClient with that URL.
return ApolloClient(networkTransport: splitTransport)
在那之后升级工作了。
【讨论】:
【参考方案3】:这是我的 ApolloClient 设置,仅用于 Web 套接字传输客户端:
let connectingPayload = ["authToken": accessToken]
let urlRequest = URLRequest(url: baseURL)
let webSocketTransport = WebSocketTransport(request: urlRequest, sendOperationIdentifiers: false, connectingPayload: connectingPayload)
let apollo = ApolloClient(networkTransport: webSocketTransport)
【讨论】:
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