diff options
| -rw-r--r-- | contrib/postgres_fdw/Makefile | 2 | ||||
| -rw-r--r-- | contrib/postgres_fdw/connection.c | 82 | ||||
| -rw-r--r-- | contrib/postgres_fdw/expected/postgres_fdw.out | 8 | ||||
| -rw-r--r-- | contrib/postgres_fdw/meson.build | 1 | ||||
| -rw-r--r-- | contrib/postgres_fdw/postgres_fdw--1.1--1.2.sql | 16 | ||||
| -rw-r--r-- | contrib/postgres_fdw/postgres_fdw.control | 2 | ||||
| -rw-r--r-- | doc/src/sgml/postgres-fdw.sgml | 21 |
7 files changed, 112 insertions, 20 deletions
diff --git a/contrib/postgres_fdw/Makefile b/contrib/postgres_fdw/Makefile index b9fa6993052..88fdce40d6a 100644 --- a/contrib/postgres_fdw/Makefile +++ b/contrib/postgres_fdw/Makefile @@ -14,7 +14,7 @@ PG_CPPFLAGS = -I$(libpq_srcdir) SHLIB_LINK_INTERNAL = $(libpq) EXTENSION = postgres_fdw -DATA = postgres_fdw--1.0.sql postgres_fdw--1.0--1.1.sql +DATA = postgres_fdw--1.0.sql postgres_fdw--1.0--1.1.sql postgres_fdw--1.1--1.2.sql REGRESS = postgres_fdw query_cancel diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c index 33e8054f643..3e902a723d4 100644 --- a/contrib/postgres_fdw/connection.c +++ b/contrib/postgres_fdw/connection.c @@ -108,9 +108,19 @@ static uint32 pgfdw_we_get_result = 0; } while(0) /* + * Extension version number, for supporting older extension versions' objects + */ +enum pgfdwVersion +{ + PGFDW_V1_1 = 0, + PGFDW_V1_2, +}; + +/* * SQL functions */ PG_FUNCTION_INFO_V1(postgres_fdw_get_connections); +PG_FUNCTION_INFO_V1(postgres_fdw_get_connections_1_2); PG_FUNCTION_INFO_V1(postgres_fdw_disconnect); PG_FUNCTION_INFO_V1(postgres_fdw_disconnect_all); @@ -159,6 +169,8 @@ static void pgfdw_security_check(const char **keywords, const char **values, UserMapping *user, PGconn *conn); static bool UserMappingPasswordRequired(UserMapping *user); static bool disconnect_cached_connections(Oid serverid); +static void postgres_fdw_get_connections_internal(FunctionCallInfo fcinfo, + enum pgfdwVersion api_version); /* * Get a PGconn which can be used to execute queries on the remote PostgreSQL @@ -1977,23 +1989,34 @@ pgfdw_finish_abort_cleanup(List *pending_entries, List *cancel_requested, } } +/* Number of output arguments (columns) for various API versions */ +#define POSTGRES_FDW_GET_CONNECTIONS_COLS_V1_1 2 +#define POSTGRES_FDW_GET_CONNECTIONS_COLS_V1_2 3 +#define POSTGRES_FDW_GET_CONNECTIONS_COLS 3 /* maximum of above */ + /* - * List active foreign server connections. + * Internal function used by postgres_fdw_get_connections variants. + * + * For API version 1.1, this function returns a set of records with + * the following values: * - * This function takes no input parameter and returns setof record made of - * following values: * - server_name - server name of active connection. In case the foreign server * is dropped but still the connection is active, then the server name will * be NULL in output. * - valid - true/false representing whether the connection is valid or not. - * Note that the connections can get invalidated in pgfdw_inval_callback. + * Note that connections can become invalid in pgfdw_inval_callback. + * + * For API version 1.2 and later, this function returns the following + * additional value along with the two values from version 1.1: + * + * - used_in_xact - true if the connection is used in the current transaction. * * No records are returned when there are no cached connections at all. */ -Datum -postgres_fdw_get_connections(PG_FUNCTION_ARGS) +static void +postgres_fdw_get_connections_internal(FunctionCallInfo fcinfo, + enum pgfdwVersion api_version) { -#define POSTGRES_FDW_GET_CONNECTIONS_COLS 2 ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo; HASH_SEQ_STATUS scan; ConnCacheEntry *entry; @@ -2002,7 +2025,22 @@ postgres_fdw_get_connections(PG_FUNCTION_ARGS) /* If cache doesn't exist, we return no records */ if (!ConnectionHash) - PG_RETURN_VOID(); + return; + + /* Check we have the expected number of output arguments */ + switch (rsinfo->setDesc->natts) + { + case POSTGRES_FDW_GET_CONNECTIONS_COLS_V1_1: + if (api_version != PGFDW_V1_1) + elog(ERROR, "incorrect number of output arguments"); + break; + case POSTGRES_FDW_GET_CONNECTIONS_COLS_V1_2: + if (api_version != PGFDW_V1_2) + elog(ERROR, "incorrect number of output arguments"); + break; + default: + elog(ERROR, "incorrect number of output arguments"); + } hash_seq_init(&scan, ConnectionHash); while ((entry = (ConnCacheEntry *) hash_seq_search(&scan))) @@ -2061,8 +2099,36 @@ postgres_fdw_get_connections(PG_FUNCTION_ARGS) values[1] = BoolGetDatum(!entry->invalidated); + if (api_version >= PGFDW_V1_2) + { + /* Is this connection used in the current transaction? */ + values[2] = BoolGetDatum(entry->xact_depth > 0); + } + tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls); } +} + +/* + * List active foreign server connections. + * + * The SQL API of this function has changed multiple times, and will likely + * do so again in future. To support the case where a newer version of this + * loadable module is being used with an old SQL declaration of the function, + * we continue to support the older API versions. + */ +Datum +postgres_fdw_get_connections_1_2(PG_FUNCTION_ARGS) +{ + postgres_fdw_get_connections_internal(fcinfo, PGFDW_V1_2); + + PG_RETURN_VOID(); +} + +Datum +postgres_fdw_get_connections(PG_FUNCTION_ARGS) +{ + postgres_fdw_get_connections_internal(fcinfo, PGFDW_V1_1); PG_RETURN_VOID(); } diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index 39b2b317e87..82fdc0e26fc 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -10464,10 +10464,10 @@ drop cascades to foreign table ft7 -- should be output as invalid connections. Also the server name for -- loopback3 should be NULL because the server was dropped. SELECT * FROM postgres_fdw_get_connections() ORDER BY 1; - server_name | valid --------------+------- - loopback | f - | f + server_name | valid | used_in_xact +-------------+-------+-------------- + loopback | f | t + | f | t (2 rows) -- The invalid connections get closed in pgfdw_xact_callback during commit. diff --git a/contrib/postgres_fdw/meson.build b/contrib/postgres_fdw/meson.build index f0803ee077e..3014086ba64 100644 --- a/contrib/postgres_fdw/meson.build +++ b/contrib/postgres_fdw/meson.build @@ -26,6 +26,7 @@ install_data( 'postgres_fdw.control', 'postgres_fdw--1.0.sql', 'postgres_fdw--1.0--1.1.sql', + 'postgres_fdw--1.1--1.2.sql', kwargs: contrib_data_args, ) diff --git a/contrib/postgres_fdw/postgres_fdw--1.1--1.2.sql b/contrib/postgres_fdw/postgres_fdw--1.1--1.2.sql new file mode 100644 index 00000000000..0c65bf2e149 --- /dev/null +++ b/contrib/postgres_fdw/postgres_fdw--1.1--1.2.sql @@ -0,0 +1,16 @@ +/* contrib/postgres_fdw/postgres_fdw--1.1--1.2.sql */ + +-- complain if script is sourced in psql, rather than via ALTER EXTENSION +\echo Use "ALTER EXTENSION postgres_fdw UPDATE TO '1.2'" to load this file. \quit + +/* First we have to remove it from the extension */ +ALTER EXTENSION postgres_fdw DROP FUNCTION postgres_fdw_get_connections (); + +/* Then we can drop it */ +DROP FUNCTION postgres_fdw_get_connections (); + +CREATE FUNCTION postgres_fdw_get_connections (OUT server_name text, + OUT valid boolean, OUT used_in_xact boolean) +RETURNS SETOF record +AS 'MODULE_PATHNAME', 'postgres_fdw_get_connections_1_2' +LANGUAGE C STRICT PARALLEL RESTRICTED; diff --git a/contrib/postgres_fdw/postgres_fdw.control b/contrib/postgres_fdw/postgres_fdw.control index d489382064c..a4b800be4fc 100644 --- a/contrib/postgres_fdw/postgres_fdw.control +++ b/contrib/postgres_fdw/postgres_fdw.control @@ -1,5 +1,5 @@ # postgres_fdw extension comment = 'foreign-data wrapper for remote PostgreSQL servers' -default_version = '1.1' +default_version = '1.2' module_pathname = '$libdir/postgres_fdw' relocatable = true diff --git a/doc/src/sgml/postgres-fdw.sgml b/doc/src/sgml/postgres-fdw.sgml index e0eac6705f1..b904f7a33ec 100644 --- a/doc/src/sgml/postgres-fdw.sgml +++ b/doc/src/sgml/postgres-fdw.sgml @@ -777,7 +777,9 @@ OPTIONS (ADD password_required 'false'); <variablelist> <varlistentry> - <term><function>postgres_fdw_get_connections(OUT server_name text, OUT valid boolean) returns setof record</function></term> + <term><function>postgres_fdw_get_connections(OUT server_name text, + OUT valid boolean, OUT used_in_xact boolean) + returns setof record</function></term> <listitem> <para> This function returns information about all open connections postgres_fdw @@ -785,11 +787,11 @@ OPTIONS (ADD password_required 'false'); no open connections, no records are returned. Example usage of the function: <screen> -postgres=# SELECT * FROM postgres_fdw_get_connections() ORDER BY 1; - server_name | valid --------------+------- - loopback1 | t - loopback2 | f +postgres=*# SELECT * FROM postgres_fdw_get_connections() ORDER BY 1; + server_name | valid | used_in_xact +-------------+-------+-------------- + loopback1 | t | t + loopback2 | f | t </screen> The output columns are described in <xref linkend="postgres-fdw-get-connections-columns"/>. @@ -827,6 +829,13 @@ postgres=# SELECT * FROM postgres_fdw_get_connections() ORDER BY 1; the transaction. True is returned otherwise. </entry> </row> + <row> + <entry><structfield>used_in_xact</structfield></entry> + <entry><type>boolean</type></entry> + <entry> + True if this connection is used in the current transaction. + </entry> + </row> </tbody> </tgroup> </table> |