Allow stream return type (#39)

ConsumePlugin/GeneratedRestClient.fs

@@ -9,6 +9,7 @@ namespace PureGym
 open System
 open System.Threading
 open System.Threading.Tasks
+open System.IO
 open RestEase
 
 /// Module for constructing a REST client.
@@ -218,4 +219,64 @@ module PureGymApi =
                     return node
                 }
                 |> (fun a -> Async.StartAsTask (a, ?cancellationToken = ct))
+
+            member _.GetStream (ct : CancellationToken option) =
+                async {
+                    let! ct = Async.CancellationToken
+
+                    let uri =
+                        System.Uri (client.BaseAddress, System.Uri ("endpoint", System.UriKind.Relative))
+
+                    let httpMessage =
+                        new System.Net.Http.HttpRequestMessage (
+                            Method = System.Net.Http.HttpMethod.Get,
+                            RequestUri = uri
+                        )
+
+                    let! response = client.SendAsync (httpMessage, ct) |> Async.AwaitTask
+                    let response = response.EnsureSuccessStatusCode ()
+                    let! node = response.Content.ReadAsStreamAsync ct |> Async.AwaitTask
+                    return node
+                }
+                |> (fun a -> Async.StartAsTask (a, ?cancellationToken = ct))
+
+            member _.GetStream' (ct : CancellationToken option) =
+                async {
+                    let! ct = Async.CancellationToken
+
+                    let uri =
+                        System.Uri (client.BaseAddress, System.Uri ("endpoint", System.UriKind.Relative))
+
+                    let httpMessage =
+                        new System.Net.Http.HttpRequestMessage (
+                            Method = System.Net.Http.HttpMethod.Get,
+                            RequestUri = uri
+                        )
+
+                    let! response = client.SendAsync (httpMessage, ct) |> Async.AwaitTask
+                    let response = response.EnsureSuccessStatusCode ()
+                    let! node = response.Content.ReadAsStreamAsync ct |> Async.AwaitTask
+                    return node
+                }
+                |> (fun a -> Async.StartAsTask (a, ?cancellationToken = ct))
+
+            member _.GetStream'' (ct : CancellationToken option) =
+                async {
+                    let! ct = Async.CancellationToken
+
+                    let uri =
+                        System.Uri (client.BaseAddress, System.Uri ("endpoint", System.UriKind.Relative))
+
+                    let httpMessage =
+                        new System.Net.Http.HttpRequestMessage (
+                            Method = System.Net.Http.HttpMethod.Get,
+                            RequestUri = uri
+                        )
+
+                    let! response = client.SendAsync (httpMessage, ct) |> Async.AwaitTask
+                    let response = response.EnsureSuccessStatusCode ()
+                    let! node = response.Content.ReadAsStreamAsync ct |> Async.AwaitTask
+                    return node
+                }
+                |> (fun a -> Async.StartAsTask (a, ?cancellationToken = ct))
         }

ConsumePlugin/RestApiExample.fs

@@ -3,6 +3,7 @@ namespace PureGym
 open System
 open System.Threading
 open System.Threading.Tasks
+open System.IO
 open RestEase
 
 [<WoofWare.Myriad.Plugins.HttpClient>]
@@ -29,3 +30,12 @@ type IPureGymApi =
 
     [<Get "endpoint/{param}">]
     abstract GetPathParam : [<Path "param">] parameter : string * ?ct : CancellationToken -> Task<string>
+
+    [<Get "endpoint">]
+    abstract GetStream : ?ct : CancellationToken -> Task<System.IO.Stream>
+
+    [<Get "endpoint">]
+    abstract GetStream' : ?ct : CancellationToken -> Task<IO.Stream>
+
+    [<Get "endpoint">]
+    abstract GetStream'' : ?ct : CancellationToken -> Task<Stream>

MyriadPlugin.Test/MyriadPlugin.Test.fsproj

@@ -9,6 +9,7 @@
   <ItemGroup>
     <Compile Include="HttpClient.fs"/>
     <Compile Include="TestPathParam.fs" />
+    <Compile Include="TestReturnTypes.fs" />
     <Compile Include="TestSurface.fs"/>
     <Compile Include="TestRemoveOptions.fs"/>
     <Compile Include="TestJsonParse.fs"/>

MyriadPlugin.Test/TestReturnTypes.fs

@@ -0,0 +1,58 @@
+namespace MyriadPlugin.Test
+
+open System
+open System.IO
+open System.Net
+open FsUnitTyped
+open System.Net.Http
+open PureGym
+open NUnit.Framework
+
+[<TestFixture>]
+module TestReturnTypes =
+
+    [<Test>]
+    let ``String return`` () =
+        let proc (message : HttpRequestMessage) : HttpResponseMessage Async =
+            async {
+                message.Method |> shouldEqual HttpMethod.Get
+                let content = new StringContent ("this is not a JSON string")
+                let resp = new HttpResponseMessage (HttpStatusCode.OK)
+                resp.Content <- content
+                return resp
+            }
+
+        use client = HttpClientMock.make (Uri "https://example.com") proc
+        let api = PureGymApi.make client
+
+        api.GetPathParam("hi").Result |> shouldEqual "this is not a JSON string"
+
+    [<TestCase "GetStream">]
+    [<TestCase "GetStream'">]
+    [<TestCase "GetStream''">]
+    let ``Stream return`` (case : string) =
+        let result = [| 1uy ; 2uy ; 3uy ; 4uy |]
+
+        let proc (message : HttpRequestMessage) : HttpResponseMessage Async =
+            async {
+                message.Method |> shouldEqual HttpMethod.Get
+                let result = new MemoryStream (result)
+                let content = new StreamContent (result)
+                let resp = new HttpResponseMessage (HttpStatusCode.OK)
+                resp.Content <- content
+                return resp
+            }
+
+        use client = HttpClientMock.make (Uri "https://example.com") proc
+        let api = PureGymApi.make client
+
+        use stream =
+            match case with
+            | "GetStream" -> api.GetStream().Result
+            | "GetStream'" -> api.GetStream'().Result
+            | "GetStream''" -> api.GetStream''().Result
+            | _ -> failwith $"unrecognised case: %s{case}"
+
+        let buf = Array.zeroCreate 10
+        stream.Read (buf, 0, 10) |> shouldEqual 4
+        Array.take 4 buf |> shouldEqual result

WoofWare.Myriad.Plugins/AstHelper.fs

@@ -116,6 +116,16 @@ module internal SynTypePatterns =
             | _ -> None
         | _ -> None
 
+    let (|Stream|_|) (fieldType : SynType) : unit option =
+        match fieldType with
+        | SynType.LongIdent ident ->
+            match ident.LongIdent |> List.map (fun i -> i.idText) with
+            | [ "System" ; "IO" ; "Stream" ]
+            | [ "IO" ; "Stream" ]
+            | [ "Stream" ] -> Some ()
+            | _ -> None
+        | _ -> None
+
     let (|NumberType|_|) (fieldType : SynType) =
         match fieldType with
         | SynType.LongIdent ident ->

WoofWare.Myriad.Plugins/HttpClientGenerator.fs

@@ -331,7 +331,8 @@ module internal HttpClientGenerator =
 
         let returnExpr =
             match info.ReturnType with
-            | String -> SynExpr.CreateIdentString "node"
+            | String
+            | Stream -> SynExpr.CreateIdentString "node"
             | _ ->
                 JsonParseGenerator.parseNode
                     None
@@ -412,6 +413,19 @@ module internal HttpClientGenerator =
                                 )
                             )
                         )
+                | Stream ->
+                    yield
+                        LetBang (
+                            "node",
+                            SynExpr.awaitTask (
+                                SynExpr.CreateApp (
+                                    SynExpr.CreateLongIdent (
+                                        SynLongIdent.Create [ "response" ; "Content" ; "ReadAsStreamAsync" ]
+                                    ),
+                                    SynExpr.CreateIdentString "ct"
+                                )
+                            )
+                        )
                 | _ ->
                     yield
                         LetBang (