feat: Download files with a shifter proxy, not the client one

src/DIRAC/WorkloadManagementSystem/Client/PilotLoggingPlugins/FileCacheDownloadPlugin.py

@@ -25,7 +25,6 @@ def __init__(self):
         """
         self.setup = gConfig.getValue("/DIRAC/Setup", None)
 
-    @executeWithUserProxy
     def getRemotePilotLogs(self, pilotStamp, vo=None):
         """
         Pilot log getter method, carrying the unique pilot identity and a VO name.
@@ -42,7 +41,21 @@ def getRemotePilotLogs(self, pilotStamp, vo=None):
         sLog.info("LFN to download: ", lfn)
         filepath = tempfile.TemporaryDirectory().name
         os.makedirs(filepath, exist_ok=True)
-        res = DataManager().getFile(lfn, destinationDir=filepath)
+        # get pilot credentials which uploaded logs to an external storage:
+        res = opsHelper.getOptionsDict("Shifter/DataManager")
+        if not res["OK"]:
+            message = f"No shifter defined for VO: {vo} - needed to retrieve the logs !"
+            sLog.error(message)
+            return S_ERROR(message)
+
+        proxyUser = res["Value"].get("User")
+        proxyGroup = res["Value"].get("Group")
+
+        sLog.info(f"Proxy used for retrieving pilot logs: VO: {vo}, User: {proxyUser}, Group: {proxyGroup}")
+
+        res = self._downloadLogs(
+            lfn, filepath, proxyUserName=proxyUser, proxyUserGroup=proxyGroup
+        )  # pylint: disable=unexpected-keyword-arg
         sLog.debug("getFile result:", res)
         if not res["OK"]:
             sLog.error(f"Failed to contact storage")
@@ -61,3 +74,7 @@ def getRemotePilotLogs(self, pilotStamp, vo=None):
         resultDict = {}
         resultDict["StdOut"] = stdout
         return S_OK(resultDict)
+
+    @executeWithUserProxy
+    def _downloadLogs(self, lfn, filepath):
+        return DataManager().getFile(lfn, destinationDir=filepath)