Limited functionality of custom middleware (Infinite loop when trying to handle HTTP request bodies) #344
Description
When using a custom middleware in a SAP UI5 application as described here, the req and res objects handed over to the middleware are of different shape. Express-specific methods like res.status() oder res.header() do not exist (which can be worked around with native Node methods tough). However, I could not find a solution for the following problem:
POST Request bodies can't be handled at all; the middleware falls into an infinite loop when trying to read them via res.on('data', ...) or other stream reading methods (or encapsulating other middlewares/parsers like http-proxy, express.json(), bodyParser.json()). When using the Chromium browser, the request is aborted after exactly 20 oder 40 seconds, a postman request seems to have no timout and runs forever (until the execution of Karma is stopped).
When serving the application directly with the same UI5 configuration and middleware files, tests can be executed without problems.
Versions:
"karma": "^6.2.0",
"karma-ui5": "^2.3.3",
"express": "^4.17.1",
"@sap/ux-ui5-tooling": "^1.2.1",
"@ui5/cli": "^2.6.4",
"@ui5/fs": "2.0.3",
"@sap/grunt-sapui5-bestpractice-build": "^1.4.13",
"@sap/ux-specification": "^1.78.8",
"@ui5/logger": "2.0.0"
ui5-testing.yaml:
specVersion: '2.1'
metadata:
name: grunt-build
type: application
framework:
name: SAPUI5
version: "1.84.0"
libraries:
- name: sap.m
- name: sap.ui.core
- name: sap.ui.layout
- name: sap.ui.support
development: true
- name: sap.ui.table
- name: sap.ui.unified
#- name: sap.ui.model
- name: sap.ushell
development: true
- name: themelib_sap_fiori_3
optional: true
- name: themelib_sap_belize
optional: true
#- name: themelib_sap_bluecrystal
# optional: true
- name: sap.f
- name: sap.tnt
resources:
configuration:
paths:
webapp: /webapp
server:
customMiddleware:
- name: proxy
beforeMiddleware: serveResources
configuration:
testing: true
---
specVersion: '2.1'
kind: extension
type: server-middleware
metadata:
name: proxy
middleware:
path: lib/middleware/proxy.js
opatests.Qunit.html:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Integration tests</title>
<script id="sap-ui-bootstrap"
src="https://sapui5.hana.ondemand.com/resources/sap-ui-core.js"
data-sap-ui-theme='sap_fiori_3'
data-sap-ui-resourceroots='{
"com.myapp.test": "../../"
}'
data-sap-ui-animation="false"
data-sap-ui-compatVersion="edge"
data-sap-ui-async="true">
</script>
<!--<link rel="stylesheet" type="text/css" href="../../../../../../../../../../resources/sap/ui/thirdparty/qunit-2.css">-->
<link rel="stylesheet" type="text/css" href="https://code.jquery.com/qunit/qunit-2.11.0.css">
<link href="https://fonts.googleapis.com/css2?family=Material+Icons+Round" rel="stylesheet">
<!--<script src="../../../../../../../../../../resources/sap/ui/thirdparty/qunit-2.js"></script>-->
<script src="https://code.jquery.com/qunit/qunit-2.11.0.js"></script>
<script src="../../../../../../../../../../resources/sap/ui/qunit/qunit-junit.js"></script>
<script src="opaTests.qunit.js"></script>
</head>
<body>
<div id="qunit"></div>
<div id="qunit-fixture"></div>
</body>
</html>
karma.conf.js:
module.exports = function (config) {
"use strict";
config.set({
frameworks: ['ui5'], //, 'qunit'],
reporters: ["progress"],
browsers: ["Chrome_without_security"],
customLaunchers: {
Chrome_without_security: {
base: 'Chrome',
flags: [
'--disable-web-security',
'--no-sandbox',
'--disable-ipc-flooding-protection',
'--no-default-browser-check'
]
}
},
client: {
runInParent: true
},
ui5: {
mode: "html",
testpage: "webapp/test/integration/opaTests.qunit.html",
configPath: "ui5-testing.yaml",
},
});
};
I assume this is a bug, otherwise I would appreciate an explanation of what is exactly going on here under the hood and wheter there is a known workaroung. Thanks!