jobs: notify on failure

custom/packages/maxwell-notify.nix

@@ -1,20 +1,35 @@
-{ writeScriptBin, fish, curl
+{ lib
+, writers
+, curl
+, jq
 , homeserver
 , roomId
 , authToken
 }:
 
-writeScriptBin "notify" ''
+writers.writeDashBin "notify" ''
-  #!${fish}/bin/fish
+  export PATH="$PATH:${lib.makeBinPath [ curl jq ]}"
 
-  set token (cat ${authToken})
+  if test $(id -u) != 0; then
-
-  if test (id -u) != 0
     echo 'you must be root to send a notice'
     exit 1
-  end
+  fi
 
-  set url '${homeserver}/rooms/${roomId}/send/m.room.message?access_token='$token
+  token=$(cat ${authToken})
-  set msg '{"msgtype":"m.text", "body": "'$argv[1]'"}'
+  url="${homeserver}/rooms/${roomId}/send/m.room.message?access_token=$token"
-  ${curl}/bin/curl -s -XPOST -d $msg $url
+
+  if test $# -eq 1; then
+    # send first arg as text
+    msg=$(printf "%s" "$1" | jq -Rsc '{ "msgtype": "m.text", "body": . }')
+  else
+    # send stdin formatted as code
+    msg=$(jq -Rsc '{
+      "msgtype": "m.text",
+      "format": "org.matrix.custom.html",
+      "body": "",
+      "formatted_body": ("<pre><code>" + . + "</code></pre>")
+      }')
+  fi
+
+  curl -s "$url" -d "$msg"
 ''

jobs.nix

@@ -4,6 +4,17 @@ with lib;
 
 {
 
+  systemd.services."notify-failed@" = {
+    description = "notify that %i has failed";
+    scriptArgs = "%i";
+    path = [ pkgs.maxwell-notify ];
+    script = ''
+      unit=$1
+      notify "$unit: failed. last log lines:"
+      journalctl -u "$unit" -o cat -n 15 | notify
+    '';
+  };
+
   systemd.services.ydns = {
     description = "update ydns address record";
     after    = [ "network-online.target" ];
@@ -63,8 +74,9 @@ with lib;
 
   in {
     description = "system backup";
-    after   = [ "network-online.target" ];
+    after       = [ "network-online.target" ];
-    startAt = "*-*-* 03:00";  # every day at 3:00
+    startAt     = "*-*-* 03:00";  # every day at 3:00
+    onFailure   = [ "notify-failed@backup.service" ];
 
     serviceConfig = {
       Type = "oneshot";
@@ -133,6 +145,7 @@ with lib;
     description = "update namecoin names";
     after       = [ "namecoind.service" ];
     startAt     = "hourly";
+    onFailure   = [ "notify-failed@namecoin-update.service" ];
 
     path = [ pkgs.namecoind ];
     serviceConfig.Type = "oneshot";