From 306e627c71bc135ff0dfe92b016f96d9b572c2ce Mon Sep 17 00:00:00 2001
From: Benedikt Terhechte <terhechte@gmail.com>
Date: Fri, 16 Dec 2022 09:15:08 +0100
Subject: [PATCH] save responses and subscriptions

---
 Sources/SwiftGraphQL/HTTP+WebSockets.swift | 31 +++++++++++++++++++-
 Sources/SwiftGraphQL/HTTP.swift            | 33 ++++++++++++++++++----
 2 files changed, 57 insertions(+), 7 deletions(-)

diff --git a/Sources/SwiftGraphQL/HTTP+WebSockets.swift b/Sources/SwiftGraphQL/HTTP+WebSockets.swift
index dc1d1061..32a21d27 100644
--- a/Sources/SwiftGraphQL/HTTP+WebSockets.swift
+++ b/Sources/SwiftGraphQL/HTTP+WebSockets.swift
@@ -101,7 +101,7 @@ public class GraphQLSocket<S: GraphQLEnabledSocket> {
 //                           log: OSLog.subscription,
 //                           type: .debug, (String(data: data, encoding: .utf8) ?? "Invalid .utf8")
 //                    )
-                    guard let message = try? JSONDecoder().decode(Message.self, from: data) else {
+                    guard var message = try? JSONDecoder().decode(Message.self, from: data) else {
                         os_log("Invalid JSON Payload", log: OSLog.subscription, type: .debug)
                         return false
                     }
@@ -130,6 +130,7 @@ public class GraphQLSocket<S: GraphQLEnabledSocket> {
                         self?.state = .running
                     case .next, .error, .complete, .data:
                         guard let id = message.id else { return false }
+                        message.originalData = data
                         self?.subscriptions[id]?(message)
                     case .connection_terminate, .connection_error:
                         self?.restart(errorHandler: errorHandler)
@@ -220,6 +221,21 @@ public class GraphQLSocket<S: GraphQLEnabledSocket> {
             self?.complete(id: id)
         }
         
+        #if DEBUG
+        #if targetEnvironment(simulator)
+        let payload = selection.buildPayload(operationName: operationName)
+
+        // Write the query. We also need the id, so we encode it into the variables
+        try? payload.query.write(toFile: "/tmp/query_\(id).graphql", atomically: true, encoding: .utf8)
+        // Write the variables
+        var copiedVariables = payload.variables
+        copiedVariables["gql-subscription-id"] = AnyCodable(stringLiteral: id)
+        if let variables = try? encoder.encode(copiedVariables) {
+            try? variables.write(to: URL(fileURLWithPath: "/tmp/query_variables_\(id).json"))
+        }
+        #endif
+        #endif
+        
         switch state {
         case .notRunning:
             if autoConnect {
@@ -260,6 +276,17 @@ public class GraphQLSocket<S: GraphQLEnabledSocket> {
                     switch message.type {
                     case .next, .data:
                         do {
+                            if let originalData = message.originalData {
+
+#if DEBUG
+#if targetEnvironment(simulator)
+                                // write the response out. A given subscription can have multiple responses.
+                                let debugTime = DispatchTime.now().uptimeNanoseconds
+                                let url = URL(fileURLWithPath: "/tmp/subscription_response_\(id)_\(debugTime).json")
+                                try? originalData.write(to: url)
+#endif
+#endif
+                            }
                             let result = try GraphQLResult(webSocketMessage: message, with: selection)
                             eventHandler(.success(result))
                         } catch {
@@ -339,6 +366,8 @@ public struct GraphQLSocketMessage: Codable {
         case pong
     }
     
+    public var originalData: Data?
+    
     public var type: MessageType
     public var id: String?
     /// Used for retreiving payload after decoding incomming message
diff --git a/Sources/SwiftGraphQL/HTTP.swift b/Sources/SwiftGraphQL/HTTP.swift
index cd090282..51f82372 100644
--- a/Sources/SwiftGraphQL/HTTP.swift
+++ b/Sources/SwiftGraphQL/HTTP.swift
@@ -89,17 +89,39 @@ private func send<Type, TypeLock>(
         return nil
     }
     
+    let debugTime = DispatchTime.now().uptimeNanoseconds
+    
     // Construct a GraphQL request.
     let request = createGraphQLRequest(
         selection: selection,
         operationName: operationName,
         url: url,
         headers: headers,
-        method: method
+        method: method,
+        debugTime: debugTime
     )
     
     // Create a completion handler.
     func onComplete(data: Data?, response: URLResponse?, error: Error?) {
+        
+        // Save the response or the error, depending on what's available
+        #if DEBUG
+        #if targetEnvironment(simulator)
+        let fallback = "\(String(describing: response))".data(using: .utf8) ?? "{'error': 'Could not serialize response'}".data(using: .utf8)!
+        let responeData: Data
+        if let data = data {
+            responeData = data
+        } else if let error = error {
+            responeData = "{'error': '\(error.localizedDescription)'}".data(using: .utf8)
+                ?? fallback
+        } else {
+            responeData = fallback
+        }
+        let url = URL(fileURLWithPath: "/tmp/query_response_\(debugTime).json")
+        try? responeData.write(to: url)
+        #endif
+        #endif
+        
         /* Process the response. */
         // Check for HTTP errors.
         if let error = error {
@@ -197,7 +219,8 @@ private func createGraphQLRequest<Type, TypeLock>(
     operationName: String?,
     url: URL,
     headers: HttpHeaders,
-    method: HttpMethod
+    method: HttpMethod,
+    debugTime: UInt64
 ) -> URLRequest where TypeLock: GraphQLOperation & Decodable {
     // Construct a request.
     var request = URLRequest(url: url)
@@ -216,12 +239,10 @@ private func createGraphQLRequest<Type, TypeLock>(
     #if DEBUG
     #if targetEnvironment(simulator)
     // Write the query
-    let time = DispatchTime.now().uptimeNanoseconds
-    let filename = operationName ?? "\(time)"
-    try? payload.query.write(toFile: "/tmp/query_\(filename).graphql", atomically: true, encoding: .utf8)
+    try? payload.query.write(toFile: "/tmp/query_\(debugTime).graphql", atomically: true, encoding: .utf8)
     // Write the variables
     if let variables = try? encoder.encode(payload.variables) {
-        try? variables.write(to: URL(fileURLWithPath: "/tmp/query_variables_\(filename).json"))
+        try? variables.write(to: URL(fileURLWithPath: "/tmp/query_variables_\(debugTime).json"))
     }
     #endif
     #endif