[FIX] web: rpc: not parsable request response

Connect in your browser to a db on runbot with mail installed and wait
until the runbot put to sleep the db. After a while, a new request to
get im_status will be sent and nginx responds to it with an error 404
and an invalid JSON response. A traceback with a particularly bad
message is then shown. Here we improve the traceback message.

closes odoo/odoo#99430

Signed-off-by: Aaron Bohy (aab) <aab@odoo.com>

addons/web/static/src/core/network/rpc_service.js

@@ -22,6 +22,8 @@ export class ConnectionLostError extends Error {}
 
 export class ConnectionAbortedError extends Error {}
 
+export class HTTPError extends Error {}
+
 // -----------------------------------------------------------------------------
 // Main RPC method
 // -----------------------------------------------------------------------------
@@ -64,7 +66,18 @@ export function jsonrpc(env, rpcId, url, params, settings = {}) {
                 reject(new ConnectionLostError());
                 return;
             }
-            const { error: responseError, result: responseResult } = JSON.parse(request.response);
+            let params;
+            try {
+                params = JSON.parse(request.response);
+            } catch (_) {
+                reject(
+                    new HTTPError(
+                        `server responded with invalid JSON response (HTTP${request.status}): ${request.response}`
+                    )
+                );
+                return;
+            }
+            const { error: responseError, result: responseResult } = params;
             if (!settings.silent) {
                 bus.trigger("RPC:RESPONSE", data.id);
             }

addons/web/static/tests/core/network/rpc_service_tests.js

@@ -252,3 +252,24 @@ QUnit.test("check connection aborted", async (assert) => {
     connection.abort();
     assert.rejects(connection, ConnectionAbortedError);
 });
+
+QUnit.test(
+    "Response with status 404 and invalid JSON response result in a rerror with a readable message",
+    async (assert) => {
+        const env = await makeTestEnv({ serviceRegistry });
+
+        const MockXHR = makeMockXHR({}, () => {});
+        const request = new MockXHR();
+        request.response = "<h...";
+        request.status = "404";
+
+        try {
+            await env.services.rpc("/test/", null, { xhr: request });
+        } catch (_e) {
+            assert.strictEqual(
+                _e.message,
+                "server responded with invalid JSON response (HTTP404): <h..."
+            );
+        }
+    }
+);