Show a big scary warning when using non-production versions

.env

@@ -1,5 +1,6 @@
 HOST=local-development.ury.org.uk
 REACT_APP_VERSION=$npm_package_version
+REACT_APP_HOMEPAGE=$npm_package_homepage
 REACT_APP_MYRADIO_NONAPI_BASE=https://ury.org.uk/myradio-staging
 REACT_APP_MYRADIO_BASE=https://ury.org.uk/api-staging/v2
 REACT_APP_BROADCAST_API_BASE=https://ury.org.uk/webstudio/api/v1

.gitignore

@@ -28,6 +28,7 @@ yarn-error.log*
 .mypy_cache/
 env/
 env.ci/
+venv/
 
 serverconfig.ini
 

Jenkinsfile

@@ -71,7 +71,7 @@ pipeline {
         }
         steps {
           sh 'sed -i -e \'s/ury.org.uk\\/webstudio-dev/ury.org.uk\\/webstudio/\' package.json'
-          sh 'REACT_APP_GIT_SHA=`git rev-parse --short HEAD` yarn build'
+          sh 'REACT_APP_GIT_SHA=`git rev-parse --short HEAD` REACT_APP_PRODUCTION=true yarn build'
           sshagent(credentials: ['ury']) {
            sh 'rsync -av --delete-after build/ deploy@ury:/usr/local/www/webstudio'
           }

src/showplanner/PISModal.tsx

@@ -3,6 +3,20 @@ import Modal from "react-modal";
 import { getLatestNewsItem, NewsEntry } from "../api";
 import { Button } from "reactstrap";
 
+function DevWarning() {
+  if (process.env.REACT_APP_PRODUCTION === "true") {
+    return null;
+  }
+  return (
+    <div style={{ color: "white", backgroundColor: "#960000" }}>
+    <h1>Development Version</h1>
+    <strong>You are using a development version of WebStudio.</strong> This version is NOT tested and may have severe bugs and performance problems.<br />
+    <em><strong>DO NOT BROADCAST LIVE SHOWS USING THIS VERSION!</strong></em><br />
+    For the latest and greatest tested WebStudio, go to <a href={process.env.REACT_APP_HOMEPAGE}>{process.env.REACT_APP_HOMEPAGE}</a>.
+    </div>
+  );
+}
+
 export function PisModal({
   close,
   isOpen,
@@ -35,6 +49,7 @@ export function PisModal({
 
   return (
     <Modal isOpen={isOpen} onRequestClose={close}>
+      <DevWarning />
       <h1>Presenter News</h1>
       {(news === "loading" || news === "not_loaded") && (
         <p>Loading the news...</p>