Added a new test for ROOT file uploads to DQMGUI

It uses a ROOT file generated by the TestDQMServicesDemo test and
uploads it to the dev DQMGUI. This should cover the case where CMSSW
moves to a new ROOT release, which might be incompatible with the one
being used at the DQMGUI.

Resolves: #43590

DQMServices/Demo/test/BuildFile.xml

@@ -6,3 +6,6 @@
 </library>
 
 <test name="TestDQMServicesDemo" command="runtests.sh"/>
+<test name="TestDQMGUIUpload" command="test_dqmgui_upload.sh">
+  <flags PRE_TEST="TestDQMServicesDemo"/>  
+</test>

DQMServices/Demo/test/test_dqmgui_upload.sh

@@ -0,0 +1,64 @@
+#!/bin/env bash
+# Simple test to use one of the files generated by TestDQMServicesDemo test
+# to upload it to the dev DQMGUI, making sure that the ROOT file format generated
+# is compatible. See cmssw issue #43590.
+# Requires curl and jq to be installed. Also requires either a Grid key and certificate,
+# or a proxy to be available.
+set -x
+set -e
+
+DEV_DQMGUI_URL="https://cmsweb.cern.ch/dqm/dev"
+# Create a unique fake "Era", so that different executions of this test
+# produce differently named files. This is required, because this test might pass
+# if it's checking a file that was successfully uploaded during a previous
+# instance of the same test.
+UNIQUE_ERA_ID=$(date -u +%Y%m%d%M%S%N)
+OLD_FILENAME=DQM_V0001_R000000001__Harvesting__DQMTests__DQMIO.root
+NEW_FILENAME=${OLD_FILENAME/DQMTests/DQMTests${UNIQUE_ERA_ID}}
+
+# Make sure the required file exists. We expect to find it in the current directory.
+if [ ! -f $OLD_FILENAME ]; then
+    echo "Unable to find required file ${OLD_FILENAME}!"
+    exit 1
+fi
+
+# Prepare curl args
+curl_args=""
+if [ -n "$X509_CERT_DIR" ]; then
+    curl_args="--capath ${X509_CERT_DIR}/ --key ${X509_USER_PROXY} --cert ${X509_USER_PROXY}"
+elif [ -n "$X509_USER_CERT" ] && [ -n "$X509_USER_CERT" ]; then
+    curl_args="--capath ${X509_CERT_DIR}/ --key ${X509_USER_KEY} --cert ${X509_USER_CERT}"
+elif [ -f $HOME/.globus/usercert.pem ] && [ -f $HOME/.globus/userkey.pem ]; then
+    curl_args="-k --key $HOME/.globus/userkey.pem --cert $HOME/.globus/usercert.pem"
+else
+    echo "Unable to find proxy or key/cert env vars, cannot continue"
+    exit 1
+fi
+
+# Make a copy with a filename that conforms to the naming convention required by DQMGUI.
+rm -f "$NEW_FILENAME"
+cp $OLD_FILENAME "$NEW_FILENAME"
+
+# Upload the file to the DQMGUI
+visDQMUpload.py "$DEV_DQMGUI_URL" "$NEW_FILENAME"
+
+# Wait for a bit for the file to be imported into the DQMGUI's index.
+# The currently used file is very small and expected to be ingested quickly,
+# but better safe than sorry.
+SECONDS_TO_WAIT=600
+# Reset shell's internal SECONDS var.
+SECONDS=0
+
+while true; do
+    # Wait for the dataset to appear in the /json/samples endpoint. It might take a while.
+    if curl -L $curl_args "${DEV_DQMGUI_URL}/data/json/samples?match=DQMTests${UNIQUE_ERA_ID}" | jq .samples[0].items[0].dataset | grep -q "$UNIQUE_ERA_ID"; then
+        exit 0
+    fi
+
+    sleep 1
+    # Timeout after SECONDS_TO_WAIT have passed.
+    if [ $SECONDS -ge $SECONDS_TO_WAIT ]; then
+        exit 10
+    fi
+done
+exit 1