Merge pull request #54 from diegobfernandez/develop

Add Option<'T> support for BindQueryString
giraffe-fsharp · May 31, 2017 · 14b0598 · 14b0598
2 parents ad7e986 + 102694f
commit 14b0598
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Showing 2 changed files with 65 additions and 2 deletions.
diff --git a/src/Giraffe/HttpContextExtensions.fs b/src/Giraffe/HttpContextExtensions.fs
@@ -7,6 +7,7 @@ open System.ComponentModel
 open Microsoft.AspNetCore.Http
 open Microsoft.Extensions.Primitives
 open Microsoft.Extensions.Logging
+open Microsoft.FSharp.Reflection
 open Microsoft.Net.Http.Headers
 open Giraffe.Common
 
@@ -87,9 +88,36 @@ type HttpContext with
                 let strValue = ref (StringValues())
                 if query.TryGetValue(p.Name, strValue)
                 then
-                    let converter = TypeDescriptor.GetConverter p.PropertyType
+                    let isOptionType = 
+                        p.PropertyType.GetTypeInfo().IsGenericType &&
+                        p.PropertyType.GetGenericTypeDefinition() = typedefof<Option<_>>
+
+                    let propertyType =
+                        if isOptionType then
+                            p.PropertyType.GetGenericArguments().[0]
+                        else
+                            p.PropertyType
+
+                    let propertyType =
+                        if propertyType.GetTypeInfo().IsValueType then
+                            (typedefof<Nullable<_>>).MakeGenericType([|propertyType|])
+                        else
+                            propertyType
+
+                    let converter = TypeDescriptor.GetConverter propertyType
+
                     let value = converter.ConvertFromInvariantString(strValue.Value.ToString())
-                    p.SetValue(obj, value, null))
+
+                    if isOptionType then
+                        let cases = FSharpType.GetUnionCases(p.PropertyType)
+                        let value =
+                            if isNull value then
+                                FSharpValue.MakeUnion(cases.[0], [||])
+                            else
+                                FSharpValue.MakeUnion(cases.[1], [|value|])
+                        p.SetValue(obj, value, null)
+                    else
+                        p.SetValue(obj, value, null))
             return obj
         }
 

diff --git a/tests/Giraffe.Tests/ModelBindingTests.fs b/tests/Giraffe.Tests/ModelBindingTests.fs
@@ -24,6 +24,13 @@ let getBody (ctx : HttpContext) =
     use reader = new StreamReader(ctx.Response.Body, Encoding.UTF8)
     reader.ReadToEnd()
 
+[<CLIMutable>]
+type ModelWithOption =
+    {
+        OptionalInt: int option
+        OptionalString: string option
+    }
+
 [<CLIMutable>]
 type Customer =
     {
@@ -203,6 +210,34 @@ let ``bindQueryString test`` () =
         let body = getBody ctx
         Assert.Equal(expected, body)
 
+[<Fact>]
+let ``bindQueryString with option property test`` () =
+    let testRoute queryStr expected =
+        let queryHandlerWithSome (ctx : HttpContext) =
+            async {
+                let! model = ctx.BindQueryString<ModelWithOption>()
+                Assert.Equal(expected, model)
+                return! setStatusCode 200 ctx
+            }
+
+        let app = GET >=> route "/" >=> queryHandlerWithSome
+
+        let ctx = Substitute.For<HttpContext>()
+        let query = Microsoft.AspNetCore.WebUtilities.QueryHelpers.ParseQuery queryStr
+        ctx.Request.Query.ReturnsForAnyArgs(QueryCollection(query) :> IQueryCollection) |> ignore
+        ctx.Request.Method.ReturnsForAnyArgs "GET" |> ignore
+        ctx.Request.Path.ReturnsForAnyArgs (PathString("/")) |> ignore
+        ctx.Response.Body <- new MemoryStream()
+
+        ctx
+        |> app
+        |> Async.RunSynchronously
+        |> ignore
+
+    testRoute "?OptionalInt=1&OptionalString=Hi" { OptionalInt = Some 1; OptionalString = Some "Hi" }
+    testRoute "?" { OptionalInt = None; OptionalString = None }
+    testRoute "?OptionalInt=&OptionalString=" { OptionalInt = None; OptionalString = Some "" }
+
 [<Fact>]
 let ``bindModel with JSON content returns correct result`` () =
     let ctx = Substitute.For<HttpContext>()