From 7c4549b936855f1d655ee1933f458817bd03e82a Mon Sep 17 00:00:00 2001
From: Jason Woofenden <jason@jasonwoof.com>
Date: Tue, 7 Jul 2015 15:28:33 -0400
Subject: [PATCH] add persistent.php (key/value store)

---
 examples/persistent.sql |    6 ++++++
 persistent.php          |   44 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 50 insertions(+)
 create mode 100644 examples/persistent.sql
 create mode 100644 persistent.php

diff --git a/examples/persistent.sql b/examples/persistent.sql
new file mode 100644
index 0000000..462b73c
--- /dev/null
+++ b/examples/persistent.sql
@@ -0,0 +1,6 @@
+drop table if exists persistent;
+create table persistent (
+	k varchar(30) binary not null default "",
+	v varchar(255) binary not null default "",
+	primary key (k)
+) CHARSET=utf8;
diff --git a/persistent.php b/persistent.php
new file mode 100644
index 0000000..cc12028
--- /dev/null
+++ b/persistent.php
@@ -0,0 +1,44 @@
+<?php
+
+# a simple, persistent, key/value store optimized for many reads
+#
+# call persistent_{get,set,clear}
+
+# for internal use
+function persistent_init() {
+	if (isset($GLOBALS['wfpl_persistent'])) {
+		return;
+	}
+	$GLOBALS['wfpl_persistent'] = array();
+	$rows = db_get_rows('persistent', 'k,v');
+	foreach ($rows as &$row) {
+		$GLOBALS['wfpl_persistent'][$row[0]] = json_decode($row[1], true);
+	} unset($row);
+}
+
+function persistent_get($k) {
+	persistent_init();
+	if (isset($GLOBALS['wfpl_persistent'][$k])) {
+		return $GLOBALS['wfpl_persistent'][$k];
+	}
+	return null;
+}
+function persistent_set($k, $v) {
+	persistent_init();
+	if (isset($GLOBALS['wfpl_persistent'][$k])) {
+		if ($GLOBALS['wfpl_persistent'][$k] === $v) {
+			return;
+		}
+		db_update('persistent', 'v', json_encode($v), 'where k=%"', $k);
+	} else {
+		db_insert('persistent', 'k,v', $k, json_encode($v));
+	}
+	$GLOBALS['wfpl_persistent'][$k] = $v;
+}
+function persistent_clear($k) {
+	persistent_init();
+	if (isset($GLOBALS['wfpl_persistent'][$k])) {
+		db_delete('persistent', 'where k=%"', $k);
+		unset($GLOBALS['wfpl_persistent'][$k]);
+	}
+}
-- 
1.7.10.4