fix(utils): now parseUndiciResponse handles compressed data before to…

… converting it (#223)

src/utils.ts

@@ -1,7 +1,9 @@
 /* eslint-disable no-redeclare */
 
 // Import Node.js Dependencies
-import { IncomingHttpHeaders } from "http";
+import { gunzip } from "node:zlib";
+import { promisify } from "node:util";
+import { IncomingHttpHeaders } from "node:http";
 
 // Import Third-party Dependencies
 import * as contentType from "content-type";
@@ -17,6 +19,7 @@ const kDefaultEncodingCharset = "utf-8";
 const kCharsetConversionTable = {
   "ISO-8859-1": "latin1"
 };
+const kAsyncGunzip = promisify(gunzip);
 
 export const DEFAULT_HEADER = { "user-agent": kDefaultUserAgent };
 
@@ -41,13 +44,21 @@ export function getEncodingCharset(charset = kDefaultEncodingCharset): BufferEnc
  * If the response as a content type equal to 'application/json' we automatically parse it with JSON.parse().
  */
 export async function parseUndiciResponse<T>(response: Dispatcher.ResponseData): Promise<T | string> {
-  const body = await response.body.text();
   const contentTypeHeader = response.headers["content-type"] as string | undefined;
-  const { type } = contentType.parse(
+  const { type, parameters } = contentType.parse(
     contentTypeHeader ?? kDefaultMimeType
   );
 
+  let body;
   try {
+    if (response.headers["content-encoding"] === "gzip") {
+      const buf = await response.body.arrayBuffer();
+      body = (await kAsyncGunzip(buf)).toString(getEncodingCharset(parameters.charset));
+    }
+    else {
+      body = await response.body.text();
+    }
+
     return type === "application/json" && body ? JSON.parse(body) : body;
   }
   catch (error) {

test/utils.spec.ts

@@ -1,5 +1,6 @@
 // Import Node.js Dependencies
 import { IncomingHttpHeaders } from "http2";
+import { gzipSync } from "zlib";
 import stream from "stream";
 
 // Import Internal Dependencies
@@ -217,6 +218,54 @@ describe("parseUndiciResponse", () => {
 
     expect(data).toStrictEqual(payload);
   });
+
+  it("must unzip data when there is a 'content-encoding' header set with 'gzip' before to converting it to a string", async() => {
+    const payload = "hello world!";
+    const body: any = {
+      async arrayBuffer() {
+        return gzipSync(payload);
+      }
+    };
+    const data = await Utils.parseUndiciResponse<string>({
+      ...defaultUndiciResponseMeta, body, headers: {
+        "content-encoding": "gzip"
+      }
+    });
+
+    expect(data).toStrictEqual(payload);
+  });
+
+  it("must unzip data when there is a 'content-encoding' header set with 'gzip' before to converting it to JSON", async() => {
+    const payload = { foo: "hello world!" };
+    const body: any = {
+      async arrayBuffer() {
+        return gzipSync(JSON.stringify(payload));
+      }
+    };
+
+    const data = await Utils.parseUndiciResponse<string>({
+      ...defaultUndiciResponseMeta, body, headers: {
+        "content-encoding": "gzip",
+        "content-type": "application/json; charset=utf-8"
+      }
+    });
+
+    expect(data).toStrictEqual(payload);
+  });
+
+  it("should not unzip data when 'content-encoding' header is not set", async() => {
+    const payload = "hello world!";
+    const buf = gzipSync(payload);
+    const body: any = {
+      text: () => buf.toString()
+    };
+
+    const data = await Utils.parseUndiciResponse<string>({
+      ...defaultUndiciResponseMeta, body, headers: {}
+    });
+
+    expect(data).toStrictEqual(buf.toString());
+  });
 });
 
 describe("getCurrentEnv", () => {