Support last update date #20

workflow/hpr_db_backup.bash

@@ -1,9 +1,23 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 # 5,20,35,50 * * * * $HOME/userfiles/sql/hpr_db_backup.bash >> $HOME/userfiles/sql/cron.log 2>&1 &
 
 # https://hackerpublicradio.org/hpr.sql.rss
 
+# Runs periodically (comment suggests every 15 minutes).
+# Gets the latest information_schema.tables.UPDATE_TIME.
+# Compares it with last_update.txt.
+# If unchanged, does nothing.
+# If changed, waits at least 5 minutes since the previous dump.
+# Creates three mysqldump files:
+#     full DB dump
+#     site dump excluding reservations
+#     another full recovery dump
+# Generates an RSS feed containing checksums of the site SQL.
+# Copies/rsyncs the site SQL and RSS to the HPR web host.
+# Records the detected DB timestamp in last_update.txt.
+
+
 #TODO
 #add a rss feed with the latest updates. Linking to the changes on gittea.
 # run that every 5 minutes and then if there is a change sleep 5 and confirm there has been no change since.
@@ -24,18 +38,11 @@ hpr_database_file="hackerpublicradio.org/public_html/hpr.sql"
 
 sync_delay_seconds="300" # 5 minutes
 
-last_update_query="SELECT
-  update_time
-FROM
-  information_schema.tables tab
-WHERE
-  update_time > (current_timestamp() - interval 30 day)
-  AND table_type = 'BASE TABLE'
-  AND table_name not in ('reservations')
-  AND table_schema not in ('information_schema', 'sys', 'performance_schema', 'mysql')
-ORDER BY
-  update_time DESC
-LIMIT 1;"
+last_update_query="USE hpr_hpr;
+SELECT GREATEST(
+    (SELECT MAX(last_changed) FROM eps),
+    (SELECT MAX(last_changed) FROM comments)
+) AS newest_last_changed;"
 
 if [ ! -s "${credential_file}" ]
 then