Merge pull request #56 from Mastercard/feature/fix-webflux-signer

Fixing Webflux Signer

Author: danny-gallagher

README.md

@@ -145,7 +145,7 @@ signer.sign(request);
 WebClient client = WebClient.create();
 ClientRequest request = ClientRequest.create(HttpMethod.POST, URI.create("https://api.mastercard.com/service"))
         .header("Content-Type", MediaType.APPLICATION_JSON_VALUE)
-        .body(BodyInserters.fromValue(yourRequestObject))
+        .body(BodyInserters.fromValue(new BodyInserterWrapper(yourRequestObject)))
         .build();
 
 SpringWebfluxSigner signer = new SpringWebfluxSigner(consumerKey, signingKey);

src/main/java/com/mastercard/developer/signers/SpringWebfluxSigner.java

@@ -1,6 +1,10 @@
 package com.mastercard.developer.signers;
 
+import com.fasterxml.jackson.databind.ObjectMapper;
 import com.mastercard.developer.oauth.OAuth;
+import org.springframework.http.ReactiveHttpOutputMessage;
+import org.springframework.web.reactive.function.BodyInserter;
+import org.springframework.web.reactive.function.BodyInserters;
 import org.springframework.web.reactive.function.client.ClientRequest;
 import reactor.core.publisher.Mono;
 
@@ -19,12 +23,36 @@ public SpringWebfluxSigner(String consumerKey, PrivateKey signingKey) {
     public ClientRequest sign(ClientRequest request) throws Exception {
         URI uri = request.url();
         String method = request.method().name();
+        BodyInserterWrapper<Object> bodyInserterWrapper = (BodyInserterWrapper<Object>) request.body();
+        String payload = new ObjectMapper().writeValueAsString(bodyInserterWrapper.getBody());
 
-        String authHeader = OAuth.getAuthorizationHeader(uri, method, request.body().toString(), charset, consumerKey, signingKey);
+        String authHeader = OAuth.getAuthorizationHeader(uri, method, payload, charset, consumerKey, signingKey);
 
         // Add auth header
         return Mono.just(ClientRequest.from(request)
                 .headers(headers -> headers.add(OAuth.AUTHORIZATION_HEADER_NAME, authHeader))
                 .build()).block();
     }
 }
+
+class BodyInserterWrapper<T> implements BodyInserter<T, ReactiveHttpOutputMessage> {
+    private final T body;
+    private final BodyInserter<T, ReactiveHttpOutputMessage> delegate;
+
+    public BodyInserterWrapper(T body) {
+        this.body = body;
+        this.delegate = BodyInserters.fromValue(body);
+    }
+
+    @Override
+    public Mono<Void> insert(
+            ReactiveHttpOutputMessage outputMessage,
+            BodyInserter.Context context
+    ) {
+        return delegate.insert(outputMessage, context);
+    }
+
+    public T getBody() {
+        return body;
+    }
+}

src/test/java/com/mastercard/developer/signers/SpringWebfluxSignerTest.java

@@ -24,10 +24,8 @@ public void testSign_ShouldAddOAuth1HeaderToPostRequest() throws Exception {
         // GIVEN
         PrivateKey signingKey = getTestSigningKey();
         String consumerKey = "Some key";
-        MediaType jsonMediaType = MediaType.parse("application/json; charset=" + UTF8_CHARSET.name());
-        RequestBody body = RequestBody.create(jsonMediaType, "{\"foo\":\"bår\"}");
-        BodyInserter<RequestBody, ReactiveHttpOutputMessage> inserter = BodyInserters.fromValue(body);
-        ClientRequest request = ClientRequest.create(HttpMethod.GET, URI.create("https://api.mastercard.com/service")).body(inserter).build();
+        BodyInserterWrapper bodyWrapper = new BodyInserterWrapper("{\"foo\":\"bår\"}");
+        ClientRequest request = ClientRequest.create(HttpMethod.GET, URI.create("https://api.mastercard.com/service")).body(bodyWrapper).build();
 
         // WHEN
         SpringWebfluxSigner instanceUnderTest = new SpringWebfluxSigner(consumerKey, signingKey);