Add examples to the WiredTiger extension methods for accessing the

metadata.

3 files changed, 104 insertions, 3 deletions

diff --git a/dist/s_string.ok b/dist/s_string.ok
index 8a3a2002816..d031f64d8ae 100644
--- a/dist/s_string.ok
+++ b/dist/s_string.ok
@@ -350,6 +350,7 @@ cxa
 data's
 datalen
 datasets
+datasource
 dbc
 decl
 decr
@@ -796,6 +797,7 @@ untyped
 upd
 upg
 uri
+uri's
 usedp
 usr
 utf
diff --git a/examples/c/ex_data_source.c b/examples/c/ex_data_source.c
index dd2b56616aa..3372d1825f4 100644
--- a/examples/c/ex_data_source.c
+++ b/examples/c/ex_data_source.c
@@ -197,6 +197,30 @@ my_open_cursor(WT_DATA_SOURCE *dsrc, WT_SESSION *session,
 	}
 
 	{
+	/*! [WT_EXTENSION config_strget] */
+	WT_CONFIG_ITEM v;
+	int64_t my_data_source_page_size;
+
+	/*
+	 * Retrieve the value of the integer type configuration string
+	 * "page_size" from a local string (as opposed to the provided
+	 * WT_CONFIG_ARG reference).
+	 */
+	const char *config_string = "path=/dev/loop,page_size=1024";
+
+	if ((ret = wt_api->config_strget(
+	    wt_api, session, config_string, "page_size", &v)) != 0) {
+		(void)wt_api->err_printf(wt_api, session,
+		    "page_size configuration: %s", wiredtiger_strerror(ret));
+		return (ret);
+	}
+	my_data_source_page_size = v.val;
+	/*! [WT_EXTENSION config_strget] */
+
+	(void)my_data_source_page_size;
+	}
+
+	{
 	/*! [WT_EXTENSION config_get] */
 	WT_CONFIG_ITEM v;
 	const char *my_data_source_key;
@@ -262,6 +286,72 @@ my_open_cursor(WT_DATA_SOURCE *dsrc, WT_SESSION *session,
 	}
 	/*! [WT_DATA_SOURCE error message] */
 
+	{
+	/*! [WT_EXTENSION metadata insert] */
+	/*
+	 * Insert a new WiredTiger metadata record.
+	 */
+	const char *key = "datasource_uri";
+	const char *value = "data source uri's record";
+
+	if ((ret = wt_api->metadata_insert(wt_api, session, key, value)) != 0) {
+		(void)wt_api->err_printf(wt_api, session,
+		    "%s: metadata insert: %s", key, wiredtiger_strerror(ret));
+		return (ret);
+	}
+	/*! [WT_EXTENSION metadata insert] */
+	}
+
+	{
+	/*! [WT_EXTENSION metadata remove] */
+	/*
+	 * Remove a WiredTiger metadata record.
+	 */
+	const char *key = "datasource_uri";
+
+	if ((ret = wt_api->metadata_remove(wt_api, session, key)) != 0) {
+		(void)wt_api->err_printf(wt_api, session,
+		    "%s: metadata remove: %s", key, wiredtiger_strerror(ret));
+		return (ret);
+	}
+	/*! [WT_EXTENSION metadata remove] */
+	}
+
+	{
+	/*! [WT_EXTENSION metadata search] */
+	/*
+	 * Insert a new WiredTiger metadata record.
+	 */
+	const char *key = "datasource_uri";
+	const char *value;
+
+	if ((ret =
+	    wt_api->metadata_search(wt_api, session, key, &value)) != 0) {
+		(void)wt_api->err_printf(wt_api, session,
+		    "%s: metadata search: %s", key, wiredtiger_strerror(ret));
+		return (ret);
+	}
+	printf("metadata: %s has a value of %s\n", key, value);
+	/*! [WT_EXTENSION metadata search] */
+	}
+
+	{
+	/*! [WT_EXTENSION metadata update] */
+	/*
+	 * Update a WiredTiger metadata record (insert it if it does not yet
+	 * exist, update it if it does).
+	 */
+	const char *key = "datasource_uri";
+	const char *value = "data source uri's record";
+
+	if ((ret = wt_api->metadata_update(wt_api, session, key, value)) != 0) {
+		(void)wt_api->err_printf(wt_api, session,
+		    "%s: metadata update: %s", key, wiredtiger_strerror(ret));
+		return (ret);
+	}
+	/*! [WT_EXTENSION metadata update] */
+	}
+
 	return (0);
 }
 
diff --git a/src/include/wiredtiger_ext.h b/src/include/wiredtiger_ext.h
index 8682171edf7..021875474e5 100644
--- a/src/include/wiredtiger_ext.h
+++ b/src/include/wiredtiger_ext.h
@@ -140,7 +140,7 @@ struct __wt_extension_api {
 	 * @param value the returned value
 	 * @errors
 	 *
-	 * @snippet ex_data_source.c WT_EXTENSION config_get
+	 * @snippet ex_data_source.c WT_EXTENSION config_strget
 	 */
 	int (*config_strget)(WT_EXTENSION_API *wt_api, WT_SESSION *session,
 	    const char *config, const char *key, WT_CONFIG_ITEM *value);
@@ -194,13 +194,15 @@ struct __wt_extension_api {
 	    WT_CONFIG_SCAN *scan, WT_CONFIG_ITEM *key, WT_CONFIG_ITEM *value);
 
 	/*!
-	 * Insert a row into the metadata.
+	 * Insert a row into the metadata if it does not already exist.
 	 *
 	 * @param wt_api the extension handle
 	 * @param session the session handle (or NULL if none available)
 	 * @param key row key
 	 * @param value row value
 	 * @errors
+	 *
+	 * @snippet ex_data_source.c WT_EXTENSION metadata insert
 	 */
 	int (*metadata_insert)(WT_EXTENSION_API *wt_api,
 	    WT_SESSION *session, const char *key, const char *value);
@@ -212,6 +214,8 @@ struct __wt_extension_api {
 	 * @param session the session handle (or NULL if none available)
 	 * @param key row key
 	 * @errors
+	 *
+	 * @snippet ex_data_source.c WT_EXTENSION metadata remove
 	 */
 	int (*metadata_remove)(
 	    WT_EXTENSION_API *wt_api, WT_SESSION *session, const char *key);
@@ -224,18 +228,23 @@ struct __wt_extension_api {
 	 * @param key row key
 	 * @param [out] valuep the row value
 	 * @errors
+	 *
+	 * @snippet ex_data_source.c WT_EXTENSION metadata search
 	 */
 	int (*metadata_search)(WT_EXTENSION_API *wt_api,
 	    WT_SESSION *session, const char *key, const char **valuep);
 
 	/*!
-	 * Update a row in the metadata.
+	 * Update a row in the metadata by either inserting a new record or
+	 * updating an existing record.
 	 *
 	 * @param wt_api the extension handle
 	 * @param session the session handle (or NULL if none available)
 	 * @param key row key
 	 * @param value row value
 	 * @errors
+	 *
+	 * @snippet ex_data_source.c WT_EXTENSION metadata update
 	 */
 	int (*metadata_update)(WT_EXTENSION_API *wt_api,
 	    WT_SESSION *session, const char *key, const char *value);