work around unreliable EDT server

epsiEDTtoICS.sh

@@ -41,7 +41,11 @@ ENDOFTEXT
     thu=$(date +%Y%m%dT%z -d "$(($offset+4-$dayOfWeek))days")
     fri=$(date +%Y%m%dT%z -d "$(($offset+5-$dayOfWeek))days")
 
-    curl -s "https://edtmobiliteng.wigorservices.net/WebPsDyn.aspx?action=posEDTBEECOME&serverid=C&Tel=${1}&date=$(date +%m/%d/%Y -d "${offset}days")" \
+    for ((i=1; i<5; i=i*2)); do
+      week="$(curl -s "https://edtmobiliteng.wigorservices.net/WebPsDyn.aspx?action=posEDTBEECOME&serverid=C&Tel=${1}&date=$(date +%m/%d/%Y -d "${offset}days")")" \
+      && { echo "$week"; break; }
+      sleep ${i}s
+    done \
     | tr '\r\n' ' ' \
     | sed -r 's/[[:blank:]]+/ /g' \
     | grep -oE '<DIV [^>]*class="Case" [^>]*style="[^"]*left *:[^"]*"|DIV [^>]*style="[^"]*left *:[^"]*" [^>]*class="Case"|<td [^>]*class="TC(ase|Prof|hdeb|Salle)"([^<]|<[^/]|</[^t]|</t[^d])*</td>' \
@@ -104,6 +108,7 @@ ENDOFTEXT
         out()
       }'
     offset=$(($offset+7))
+    sleep 0.3s
   done
 
   cat <<-ENDOFTEXT