Fix: detect failure (timeout...) on login (no token -> following requests were unauthorized).

bin/get-config

@@ -3,7 +3,21 @@
 API_BASE_URL=https://labmanager-api.edu-al.unipmn.it/api/1.0
 
 function getTokenJSON() {
-    echo `curl -s -k --max-time 10 -X POST -H "Content-Type: application/json" -d "{\"login\":\"guest\",\"pwd\":\"\"}" ${API_BASE_URL}/login`
+    # store the whole response with the status at the end
+    HTTP_RESPONSE=$(curl -s -k -w "HTTPSTATUS:%{http_code}" --max-time 10 -X POST -H "Content-Type: application/json" -d "{\"login\":\"guest\",\"pwd\":\"\"}" ${API_BASE_URL}/login)
+    # extract the body
+    HTTP_BODY=$(echo "$HTTP_RESPONSE" | sed -e 's/HTTPSTATUS\:.*//g')
+    # extract the status
+    HTTP_STATUS=$(echo "$HTTP_RESPONSE" | tr -d '\n' | sed -e 's/.*HTTPSTATUS://')
+
+    # check the status
+    if [[ $HTTP_STATUS -ne 200  ]]
+    then
+        echo "Error authenticating to server (http_status=$HTTP_STATUS)"
+        exit 1
+    else
+        echo $HTTP_BODY
+    fi
 }