Merge pull request #1283 from relu91/fix-854

Support for default accept header in http client

Author: egekorkan

packages/binding-http/src/http-client-impl.ts

@@ -112,7 +112,10 @@ export default class HttpClient implements ProtocolClient {
     }
 
     public async readResource(form: HttpForm): Promise<Content> {
-        const request = await this.generateFetchRequest(form, "GET");
+        // See https://www.w3.org/TR/wot-thing-description11/#contentType-usage
+        // Case: 1B
+        const headers = form.contentType != null ? [["accept", form.contentType]] : [["accept", ContentSerdes.DEFAULT]];
+        const request = await this.generateFetchRequest(form, "GET", { headers });
         debug(`HttpClient (readResource) sending ${request.method} to ${request.url}`);
 
         const result = await this.fetch(request);
@@ -176,6 +179,15 @@ export default class HttpClient implements ProtocolClient {
 
     public async invokeResource(form: HttpForm, content?: Content): Promise<Content> {
         const headers = content != null ? [["content-type", content.type]] : [];
+        // See https://www.w3.org/TR/wot-thing-description11/#contentType-usage
+        // Cases: 1C and 2A
+        if (form.response?.contentType != null) {
+            headers.push(["accept", form.response?.contentType]);
+        } else if (form.contentType != null) {
+            headers.push(["accept", form.contentType]);
+        } else {
+            headers.push(["accept", ContentSerdes.DEFAULT]);
+        }
 
         const request = await this.generateFetchRequest(form, "POST", {
             headers,
@@ -347,12 +359,20 @@ export default class HttpClient implements ProtocolClient {
 
             const headers = form["htv:headers"] as Array<HttpHeader>;
             for (const option of headers) {
+                // override defaults
+                requestInit.headers = requestInit.headers.filter(
+                    (header) => header[0].toLowerCase() !== option["htv:fieldName"].toLowerCase()
+                );
                 requestInit.headers.push([option["htv:fieldName"], option["htv:fieldValue"]]);
             }
         } else if (typeof form["htv:headers"] === "object") {
             debug(`HttpClient got Form SINGLE-ENTRY 'headers' ${form["htv:headers"]}`);
 
             const option = form["htv:headers"] as HttpHeader;
+            // override defaults
+            requestInit.headers = requestInit.headers.filter(
+                (header) => header[0].toLowerCase() !== option["htv:fieldName"].toLowerCase()
+            );
             requestInit.headers.push([option["htv:fieldName"], option["htv:fieldValue"]]);
         }
 

packages/binding-http/test/http-client-test.ts

@@ -50,6 +50,7 @@ interface TestVector {
     method?: string;
     schema?: DataSchema;
     payload?: DataSchemaValue;
+    headers?: Record<string, string>;
     form: Form;
 }
 
@@ -153,6 +154,10 @@ class TestHttpServer implements ProtocolServer {
         expect(req.method).to.equal(this.testVector.method);
         expect(req.url).to.equal(new URL(this.testVector.form.href).pathname);
 
+        if (this.testVector.headers) {
+            expect(req.headers).to.include(this.testVector.headers);
+        }
+
         if (this.testVector.payload !== undefined) {
             // load payload
             const body: Array<Uint8Array> = [];
@@ -211,6 +216,9 @@ class HttpClientTest1 {
             form: <HttpForm>{
                 href: `http://localhost:${port1}/`,
             },
+            headers: {
+                accept: "application/json",
+            },
         };
         HttpClientTest1.httpServer.setTestVector(inputVector1);
         const resource = await this.client.readResource(inputVector1.form);
@@ -225,6 +233,9 @@ class HttpClientTest1 {
             form: <HttpForm>{
                 href: `http://localhost:${port1}/`,
             },
+            headers: {
+                "content-type": "application/json",
+            },
             payload: "test",
         };
         HttpClientTest1.httpServer.setTestVector(inputVector2);
@@ -239,6 +250,10 @@ class HttpClientTest1 {
             form: <HttpForm>{
                 href: `http://localhost:${port1}/`,
             },
+            headers: {
+                "content-type": "application/json",
+                accept: "application/json",
+            },
             payload: "test",
         };
         HttpClientTest1.httpServer.setTestVector(inputVector3);
@@ -269,7 +284,46 @@ class HttpClientTest1 {
         body.toString("ascii").should.eql("");
     }
 
-    @test async "should apply form information - read with POST instead of PUT"() {
+    @test async "should apply form information - read with not default content-type"() {
+        // read with defaults
+        const inputVector1 = {
+            op: ["readproperty"],
+            form: <HttpForm>{
+                href: `http://localhost:${port1}/`,
+                contentType: "text/plain",
+            },
+            headers: {
+                accept: "text/plain",
+            },
+        };
+        HttpClientTest1.httpServer.setTestVector(inputVector1);
+        const resource = await this.client.readResource(inputVector1.form);
+        const body = await resource.toBuffer();
+        body.toString("ascii").should.eql("");
+    }
+
+    @test async "should apply form information - read with header override"() {
+        // read with defaults
+        const inputVector1 = {
+            op: ["readproperty"],
+            form: <HttpForm>{
+                href: `http://localhost:${port1}/`,
+                "htv:headers": {
+                    "htv:fieldName": "accept",
+                    "htv:fieldValue": "text/plain",
+                },
+            },
+            headers: {
+                accept: "text/plain",
+            },
+        };
+        HttpClientTest1.httpServer.setTestVector(inputVector1);
+        const resource = await this.client.readResource(inputVector1.form);
+        const body = await resource.toBuffer();
+        body.toString("ascii").should.eql("");
+    }
+
+    @test async "should apply form information - write with POST instead of PUT"() {
         // write with POST instead of PUT
         const inputVector2 = {
             op: ["writeproperty"],
@@ -283,7 +337,7 @@ class HttpClientTest1 {
         await this.client.writeResource(inputVector2.form, new DefaultContent(Readable.from(inputVector2.payload)));
     }
 
-    @test async "should apply form information - read with PUT instead of GET"() {
+    @test async "should apply form information - invoke with PUT instead of GET"() {
         // invoke with PUT instead of POST
         const inputVector3 = {
             op: ["invokeaction"],
@@ -297,7 +351,7 @@ class HttpClientTest1 {
         await this.client.invokeResource(inputVector3.form, new DefaultContent(Readable.from(inputVector3.payload)));
     }
 
-    @test async "should apply form information - read with DELETE instead of POST"() {
+    @test async "should apply form information - invoke with DELETE instead of POST"() {
         // invoke with DELETE instead of POST
         const inputVector4 = {
             op: ["invokeaction"],
@@ -309,6 +363,63 @@ class HttpClientTest1 {
         HttpClientTest1.httpServer.setTestVector(inputVector4);
         await this.client.invokeResource(inputVector4.form);
     }
+
+    @test async "should apply form information - invoke with not default content-type and no inputs"() {
+        // invoke with DELETE instead of POST
+        const inputVector4 = {
+            op: ["invokeaction"],
+            form: <HttpForm>{
+                href: `http://localhost:${port1}/`,
+                contentType: "text/plain",
+            },
+            headers: {
+                accept: "text/plain",
+            },
+        };
+        HttpClientTest1.httpServer.setTestVector(inputVector4);
+        await this.client.invokeResource(inputVector4.form);
+    }
+
+    @test async "should apply form information - invoke with not default content-type"() {
+        // invoke with DELETE instead of POST
+        const inputVector4 = {
+            op: ["invokeaction"],
+            form: <HttpForm>{
+                href: `http://localhost:${port1}/`,
+                contentType: "text/plain",
+            },
+            headers: {
+                "content-type": "text/plain",
+                accept: "text/plain",
+            },
+            payload: "test",
+        };
+        HttpClientTest1.httpServer.setTestVector(inputVector4);
+        await this.client.invokeResource(
+            inputVector4.form,
+            new Content("text/plain", Readable.from(inputVector4.payload))
+        );
+    }
+
+    @test async "should apply form information - invoke with default content-type and response content-type"() {
+        // invoke with DELETE instead of POST
+        const inputVector4 = {
+            op: ["invokeaction"],
+            form: <HttpForm>{
+                href: `http://localhost:${port1}/`,
+                response: {
+                    contentType: "text/plain",
+                },
+            },
+            headers: {
+                "content-type": "application/json",
+                accept: "text/plain",
+            },
+            payload: "test",
+        };
+        HttpClientTest1.httpServer.setTestVector(inputVector4);
+        await this.client.invokeResource(inputVector4.form, new DefaultContent(Readable.from(inputVector4.payload)));
+    }
 }
 
 @suite("HTTP client subscriptions")