Improve test host disposal and introspection file update safety

Agent-Logs-Url: https://github.com/fsprojects/FSharp.Data.GraphQL/sessions/4998e0af-9a24-4088-a9a9-3318b08f3de9

Co-authored-by: xperiandri <2365592+xperiandri@users.noreply.github.com>

Author: Copilot

tests/FSharp.Data.GraphQL.IntegrationTests/IntrospectionUpdateTests.fs

@@ -42,7 +42,7 @@ let readDestinationDocumentAsync ct (stream : FileStream) =
 let updateIntrospectionFileAsync ct sourceStream =
     task {
         use destinationStream =
-            new FileStream (introspectionFilePath, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.None)
+            new FileStream (introspectionFilePath, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.Read)
 
         let options = JsonWriterOptions(Indented = true)
         let! sourceDocument = parseAndNormalizeJsonAsync ct options sourceStream
@@ -67,8 +67,7 @@ let updateIntrospectionFileAsync ct sourceStream =
 [<Fact>]
 let ``Get GraphQL introspection response returns schema`` () =
     task {
-        use factory = new TestHosts.IntegrationServerApplicationFactory ()
-        use httpClient = factory.CreateClient ()
+        use httpClient = TestHosts.createIntegrationHttpClient ()
         let! response = httpClient.GetFromJsonAsync<JsonElement>("/", CancellationToken.None)
         let schema = response.GetProperty("data").GetProperty("__schema")
         Assert.NotEqual(Unchecked.defaultof<JsonElement>, schema)
@@ -79,8 +78,7 @@ let ``Get GraphQL introspection response returns schema`` () =
 [<Fact>]
 let ``Update integration introspection file when schema changes`` () =
     task {
-        use factory = new TestHosts.IntegrationServerApplicationFactory ()
-        use httpClient = factory.CreateClient ()
+        use httpClient = TestHosts.createIntegrationHttpClient ()
         let! sourceStream = httpClient.GetStreamAsync("/")
         let! _ = updateIntrospectionFileAsync CancellationToken.None sourceStream
         Assert.True(File.Exists introspectionFilePath)

tests/FSharp.Data.GraphQL.IntegrationTests/TestHosts.fs

@@ -3,25 +3,40 @@ module FSharp.Data.GraphQL.IntegrationTests.TestHosts
 open FSharp.Data.GraphQL
 open Microsoft.AspNetCore.Mvc.Testing
 open System.Net.Http
+open System
 
 type IntegrationServerApplicationFactory () =
     inherit WebApplicationFactory<FSharp.Data.GraphQL.IntegrationTests.Server.Startup> ()
 
 type StarWarsApplicationFactory () =
     inherit WebApplicationFactory<FSharp.Data.GraphQL.Samples.StarWarsApi.Startup> ()
 
+let private integrationFactory = lazy (new IntegrationServerApplicationFactory ())
+let private starWarsFactory = lazy (new StarWarsApplicationFactory ())
+
 let private integrationClient : Lazy<HttpClient> =
-    lazy
-        (let factory = new IntegrationServerApplicationFactory ()
-         factory.CreateClient ())
+    lazy (integrationFactory.Value.CreateClient ())
 
 let private starWarsClient : Lazy<HttpClient> =
-    lazy
-        (let factory = new StarWarsApplicationFactory ()
-         factory.CreateClient ())
+    lazy (starWarsFactory.Value.CreateClient ())
+
+do
+    AppDomain.CurrentDomain.ProcessExit.Add(fun _ ->
+        if integrationClient.IsValueCreated then
+            integrationClient.Value.Dispose ()
+
+        if starWarsClient.IsValueCreated then
+            starWarsClient.Value.Dispose ()
+
+        if integrationFactory.IsValueCreated then
+            integrationFactory.Value.Dispose ()
+
+        if starWarsFactory.IsValueCreated then
+            starWarsFactory.Value.Dispose ())
 
 let integrationServerUrl = integrationClient.Value.BaseAddress.ToString().TrimEnd '/'
 let starWarsServerUrl = starWarsClient.Value.BaseAddress.ToString().TrimEnd '/'
 
 let createIntegrationConnection () = new GraphQLClientConnection (integrationClient.Value)
 let createStarWarsConnection () = new GraphQLClientConnection (starWarsClient.Value)
+let createIntegrationHttpClient () = integrationFactory.Value.CreateClient ()