Accept: Check that the update is written

Check that the static topology update is written to disk,
and that it does not differ from the version served by
the discovery service.

acceptance/discovery_infra_fetches_static_acceptance/test

@@ -1,7 +1,7 @@
 #!/bin/bash
 
 # This test checks that the infra services fetch the static topology
-# from the discovery service.
+# from the discovery service, and that it writes the update to disk.
 
 PROGRAM=`basename "$0"`
 COMMAND="$1"
@@ -14,9 +14,12 @@ test_setup() {
     set -e
     base_setup
 
-    for cfg in gen/ISD1/AS$AS_FILE/*/{cs,ps}config.toml; do
-        set_log_lvl "$cfg"
-        set_interval "$cfg" "static"
+    for elem in gen/ISD1/AS$AS_FILE/{cs,ps}*; do
+        for cfg in $elem/*.toml; do
+            set_log_lvl "$cfg"
+            set_interval "$cfg" "static"
+            sed -i -e "/\[discovery.static]/a Filename = \"/share/cache/${elem##*/}-topo.json\"" $cfg
+        done
     done
 
     base_start_scion
@@ -27,14 +30,25 @@ test_run() {
     # Start serving static topology.
     jq ".BorderRouters[].InternalAddrs.IPv4.PublicOverlay = {Addr: \"127.42.42.42\", OverlayPort: 39999} | .Timestamp = $( date +%s) | .TTL = 3" $TOPO | sponge $STATIC_FULL
     sleep 6
+    # Check that the mock ds serves the file
     check_file "static"
+    # Check that the logs contain setting and writing the topo.
     check_logs "ps$IA_FILE-1"
     check_logs "cs$IA_FILE-1"
+    # Check that the written file does not differ from the served file.
+    check_diff "ps$IA_FILE-1"
+    check_diff "cs$IA_FILE-1"
 }
 
 check_logs() {
     grep -q "\[discovery\] Set topology .* Mode=static" "logs/$1.log" || \
         { echo "Setting static topology not found in logs. id=$1"; return 1; }
+    grep -q "\[discovery\] Topology written to filesystem .* Mode=static" "logs/$1.log" || \
+        { echo "Writing static topology not found in logs. id=$1"; return 1; }
+}
+
+check_diff () {
+    diff -q $STATIC_FULL gen-cache/$1-topo.json
 }
 
 shift