Make prom-collect generic

ansible/roles/common/templates/prom-collect.j2

@@ -1,15 +1,12 @@
 #!/bin/sh
 
-metric="$1"
+name="$1"
+value="$2"
 txtdir=/var/lib/prometheus/textfile_collector
-time="$(date +%s)"
 
-cat << EOF > "$txtdir/$metric.prom.$$"
-${metric}_last_run_seconds $time
-EOF
+printf "$name $value" > "$txtdir/$name.prom.$$"
 
 # Rename the temporary file atomically.
 # This avoids the node exporter seeing half a file.
-mv "$txtdir/$metric.prom.$$" \
-  "$txtdir/$metric.prom"
-
+mv "$txtdir/$name.prom.$$" \
+  "$txtdir/$name.prom"

ansible/roles/postgresql/templates/pg_backup.j2

@@ -5,4 +5,4 @@
 
 cd /var/lib/postgresql
 sudo -u postgres pg_dumpall | gzip -9 > "pgbackup.gz"
-prom-collect postgresql_backup
+prom-collect postgresql_backup_last_run_seconds $(date +%s)

builds/daily/postgres-backups.yaml

@@ -26,5 +26,5 @@ tasks:
   - metrics: |
       for server in "${targets[@]}"
       do
-        ssh "$server" prom-collect postgresql_offsite_backup
+        ssh "$server" prom-collect postgresql_offsite_backup_last_run_seconds $(date +%s)
       done