Preserve response body on api requests with XML response types. (#4180)

Today, apiv2 will try to parse XML responses as JSON with poor results, e.g.

```
⚠ functions: Upload Error: Unable to parse JSON: SyntaxError: Unexpected token < in JSON at position 0

Error: Unable to parse JSON: SyntaxError: Unexpected token < in JSON at position 0
```

Here, we explicitly add support for `xml` as a responseType and deal with it as a string. E.g.

```
⚠  functions: Upload Error: HTTP Error: 400, <?xml version='1.0' encoding='UTF-8'?><Error><Code>EntityTooLarge</Code><Message>Your proposed upload is larger than the maximum object size specified in your Policy Document.</Message><Details>Content-length exceeds upper bound on range</Details></Error>

Error: HTTP Error: 400, <?xml version='1.0' encoding='UTF-8'?><Error><Code>EntityTooLarge</Code><Message>Your proposed upload is larger than the maximum object size specified in your Policy Document.</Message><Details>Content-length exceeds upper bound on range</Details></Error>
```

Fixes #4146

CHANGELOG.md

@@ -4,4 +4,5 @@
 - Fixes broken functions:config:clone command (#4173).
 - Fixes issue where `auth:import` would fail when reading a JSON file. (#4157)
 - Fixes issue where custom claims added in Auth Emulator UI was not properly shown.
+- Improves handling of API requests with XML responses (#4180).
 - Updates the underlying request library in Hosting deploys and uses project-scoped URLs. (#2558)

src/apiv2.ts

@@ -23,7 +23,7 @@ interface BaseRequestOptions<T> extends VerbOptions {
   method: HttpMethod;
   path: string;
   body?: T | string | NodeJS.ReadableStream;
-  responseType?: "json" | "stream";
+  responseType?: "json" | "stream" | "xml";
   redirect?: "error" | "follow" | "manual";
   compress?: boolean;
 }
@@ -415,6 +415,8 @@ export class Client {
                 throw new FirebaseError(`Unable to parse JSON: ${err}`);
               }
             }
+          } else if (options.responseType === "xml") {
+            body = (await res.text()) as unknown as ResT;
           } else if (options.responseType === "stream") {
             body = res.body as unknown as ResT;
           } else {

src/gcp/storage.ts

@@ -158,6 +158,7 @@ export async function upload(
     method: "PUT",
     path: url.pathname,
     queryParams: url.searchParams,
+    responseType: "xml",
     headers: {
       "content-type": "application/zip",
       ...extraHeaders,

src/responseToError.js

@@ -4,18 +4,26 @@ const _ = require("lodash");
 const { FirebaseError } = require("./error");
 
 module.exports = function (response, body) {
-  if (typeof body === "string" && response.statusCode === 404) {
-    body = {
-      error: {
-        message: "Not Found",
-      },
-    };
-  }
-
   if (response.statusCode < 400) {
     return null;
   }
 
+  if (typeof body === "string") {
+    if (response.statusCode === 404) {
+      body = {
+        error: {
+          message: "Not Found",
+        },
+      };
+    } else {
+      body = {
+        error: {
+          message: body,
+        },
+      };
+    }
+  }
+
   if (typeof body !== "object") {
     try {
       body = JSON.parse(body);

src/test/apiv2.spec.ts

@@ -394,6 +394,36 @@ describe("apiv2", () => {
       expect(nock.isDone()).to.be.true;
     });
 
+    it("should preserve XML messages", async () => {
+      const xml = "<?xml version='1.0' encoding='UTF-8'?><Message>Hello!</Message>";
+      nock("https://example.com").get("/path/to/foo").reply(200, xml);
+
+      const c = new Client({ urlPrefix: "https://example.com" });
+      const r = await c.request({
+        method: "GET",
+        path: "/path/to/foo",
+        responseType: "xml",
+      });
+      expect(r.body).to.deep.equal(xml);
+      expect(nock.isDone()).to.be.true;
+    });
+
+    it("should preserve XML messages on error", async () => {
+      const xml =
+        "<?xml version='1.0' encoding='UTF-8'?><Error><Code>EntityTooLarge</Code></Error>";
+      nock("https://example.com").get("/path/to/foo").reply(400, xml);
+
+      const c = new Client({ urlPrefix: "https://example.com" });
+      await expect(
+        c.request({
+          method: "GET",
+          path: "/path/to/foo",
+          responseType: "xml",
+        })
+      ).to.eventually.be.rejectedWith(FirebaseError, /EntityTooLarge/);
+      expect(nock.isDone()).to.be.true;
+    });
+
     describe("with a proxy", () => {
       let proxyServer: Server;
       let targetServer: Server;