fix [BUG] AuthorizeAttribute does not add a header to the request rea…

…ctiveui#946

README.md

@@ -471,10 +471,23 @@ Task<User> GetUser(string user, [Header("Authorization")] string authorization);
 var user = await GetUser("octocat", "token OAUTH-TOKEN"); 
 ```
 
-#### Authorization (Dynamic Headers redux)
+#### Dynamic authorization header with scheme
 The most common reason to use headers is for authorization. Today most API's use some flavor of oAuth with access tokens that expire and refresh tokens that are longer lived.
 
-One way to encapsulate these kinds of token usage, a custom `HttpClientHandler` can be inserted instead.  
+If you want to set an access token at runtime and specify the authorization scheme (e.g. "Bearer"),
+you can add a dynamic value to a request by applying an `Authorize` attribute to a parameter:
+
+```csharp
+[Get("/users/{user}")]
+Task<User> GetUser(string user, [Authorize("Bearer")] string token);
+
+// Will add the header "Authorization: Bearer OAUTH-TOKEN}" to the request
+var user = await GetUser("octocat", "OAUTH-TOKEN"); 
+```
+
+#### Authorization (Dynamic Headers redux)
+
+Another way to encapsulate these kinds of token usage, a custom `HttpClientHandler` can be inserted instead.  
 There are two classes for doing this: one is `AuthenticatedHttpClientHandler`, which takes a `Func<Task<string>>` parameter, where a signature can be generated without knowing about the request.
 The other is `AuthenticatedParameterizedHttpClientHandler`, which takes a `Func<HttpRequestMessage, Task<string>>` parameter, where the signature requires information about the request (see earlier notes about Twitter's API)
 

Refit.Tests/RequestBuilder.cs

@@ -50,6 +50,9 @@ public interface IRestMethodInfoTests
         [Post("/foo/bar/{id}")]
         IObservable<string> PostSomeUrlEncodedStuff([AliasAs("id")] int anId, [Body(BodySerializationMethod.UrlEncoded)] Dictionary<string, string> theData);
 
+        [Get("/foo/bar/{id}")]
+        IObservable<string> FetchSomeStuffWithAuthorizationSchemeSpecified([AliasAs("id")] int anId, [Authorize("Bearer")] string token);
+
         [Get("/foo/bar/{id}")]
         [Headers("Api-Version: 2 ")]
         Task<string> FetchSomeStuffWithHardcodedHeaders(int id);
@@ -482,6 +485,19 @@ public void FindTheBodyParameter()
             Assert.Equal(1, fixture.BodyParameterInfo.Item3);
         }
 
+        [Fact]
+        public void FindTheAuthorizeParameter()
+        {
+            var input = typeof(IRestMethodInfoTests);
+            var fixture = new RestMethodInfo(input, input.GetMethods().First(x => x.Name == nameof(IRestMethodInfoTests.FetchSomeStuffWithAuthorizationSchemeSpecified)));
+            Assert.Equal("id", fixture.ParameterMap[0].Name);
+            Assert.Equal(ParameterType.Normal, fixture.ParameterMap[0].Type);
+
+            Assert.NotNull(fixture.AuthorizeParameterInfo);
+            Assert.Empty(fixture.QueryParameterMap);
+            Assert.Equal(1, fixture.AuthorizeParameterInfo.Item2);
+        }
+
         [Fact]
         public void AllowUrlEncodedContent()
         {

Refit/Attributes.cs

@@ -207,10 +207,14 @@ public HeaderAttribute(string header)
     }
 
     [AttributeUsage(AttributeTargets.Parameter)]
-    public class AuthorizeAttribute : HeaderAttribute
+    public class AuthorizeAttribute : Attribute
     {
         public AuthorizeAttribute(string scheme = "Bearer")
-            : base("Authorization: " + scheme) { }
+        {
+            Scheme = scheme;
+        }
+
+        public string Scheme { get; }
     }
 
     [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Property)] // Property is to allow for form url encoded data

Refit/RequestBuilderImplementation.cs

@@ -578,6 +578,12 @@ Func<object[], Task<HttpRequestMessage>> BuildRequestFactoryForMethod(RestMethod
                         isParameterMappedToRequest = true;
                     }
 
+                    //if authorize, add to request headers with scheme
+                    if (restMethod.AuthorizeParameterInfo != null && restMethod.AuthorizeParameterInfo.Item2 == i)
+                    {
+                        headersToAdd["Authorization"] = $"{restMethod.AuthorizeParameterInfo.Item1} {param}";
+                    }
+
                     // ignore nulls and already processed parameters
                     if (isParameterMappedToRequest || param == null) continue;
 

Refit/RestMethodInfo.cs

@@ -25,6 +25,7 @@ public class RestMethodInfo
         public Dictionary<string, string> Headers { get; set; }
         public Dictionary<int, string> HeaderParameterMap { get; set; }
         public Tuple<BodySerializationMethod, bool, int> BodyParameterInfo { get; set; }
+        public Tuple<string, int> AuthorizeParameterInfo { get; set; }
         public Dictionary<int, string> QueryParameterMap { get; set; }
         public Dictionary<int, Tuple<string, string>> AttachmentNameMap { get; set; }
         public Dictionary<int, ParameterInfo> ParameterInfoMap { get; set; }
@@ -70,6 +71,7 @@ public RestMethodInfo(Type targetInterface, MethodInfo methodInfo, RefitSettings
                 .ToDictionary(x => x.index, x => x.parameter);
             ParameterMap = BuildParameterMap(RelativePath, parameterList);
             BodyParameterInfo = FindBodyParameter(parameterList, IsMultipart, hma.Method);
+            AuthorizeParameterInfo = FindAuthorizationParameter(parameterList);
 
             Headers = ParseHeaders(methodInfo);
             HeaderParameterMap = BuildHeaderParameterMap(parameterList);
@@ -98,7 +100,8 @@ public RestMethodInfo(Type targetInterface, MethodInfo methodInfo, RefitSettings
             {
                 if (ParameterMap.ContainsKey(i) ||
                     HeaderParameterMap.ContainsKey(i) ||
-                    (BodyParameterInfo != null && BodyParameterInfo.Item3 == i))
+                    (BodyParameterInfo != null && BodyParameterInfo.Item3 == i) ||
+                    (AuthorizeParameterInfo != null && AuthorizeParameterInfo.Item2 == i))
                 {
                     continue;
                 }                
@@ -296,6 +299,27 @@ Tuple<BodySerializationMethod, bool, int> FindBodyParameter(IList<ParameterInfo>
             return null;
         }
 
+        Tuple<string, int> FindAuthorizationParameter(IList<ParameterInfo> parameterList)
+        {
+            var authorizeParams = parameterList
+                .Select(x => new { Parameter = x, AuthorizeAttribute = x.GetCustomAttributes(true).OfType<AuthorizeAttribute>().FirstOrDefault() })
+                .Where(x => x.AuthorizeAttribute != null)
+                .ToList();
+
+            if (authorizeParams.Count > 1)
+            {
+                throw new ArgumentException("Only one parameter can be an Authorize parameter");
+            }
+
+            if (authorizeParams.Count == 1)
+            {
+                var ret = authorizeParams[0];
+                return Tuple.Create(ret.AuthorizeAttribute.Scheme, parameterList.IndexOf(ret.Parameter));
+            }
+
+            return null;
+        }
+
         Dictionary<string, string> ParseHeaders(MethodInfo methodInfo)
         {
             var ret = new Dictionary<string, string>();