@ -65,6 +65,23 @@ static void message_cb_wrapper(ReorderBuffer *cache, ReorderBufferTXN *txn,
XLogRecPtr message_lsn , bool transactional ,
const char * prefix , Size message_size , const char * message ) ;
/* streaming callbacks */
static void stream_start_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
XLogRecPtr first_lsn ) ;
static void stream_stop_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
XLogRecPtr last_lsn ) ;
static void stream_abort_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
XLogRecPtr abort_lsn ) ;
static void stream_commit_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
XLogRecPtr commit_lsn ) ;
static void stream_change_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
Relation relation , ReorderBufferChange * change ) ;
static void stream_message_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
XLogRecPtr message_lsn , bool transactional ,
const char * prefix , Size message_size , const char * message ) ;
static void stream_truncate_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
int nrelations , Relation relations [ ] , ReorderBufferChange * change ) ;
static void LoadOutputPlugin ( OutputPluginCallbacks * callbacks , char * plugin ) ;
/*
@ -189,6 +206,39 @@ StartupDecodingContext(List *output_plugin_options,
ctx - > reorder - > commit = commit_cb_wrapper ;
ctx - > reorder - > message = message_cb_wrapper ;
/*
* To support streaming , we require start / stop / abort / commit / change
* callbacks . The message and truncate callbacks are optional , similar to
* regular output plugins . We however enable streaming when at least one
* of the methods is enabled so that we can easily identify missing
* methods .
*
* We decide it here , but only check it later in the wrappers .
*/
ctx - > streaming = ( ctx - > callbacks . stream_start_cb ! = NULL ) | |
( ctx - > callbacks . stream_stop_cb ! = NULL ) | |
( ctx - > callbacks . stream_abort_cb ! = NULL ) | |
( ctx - > callbacks . stream_commit_cb ! = NULL ) | |
( ctx - > callbacks . stream_change_cb ! = NULL ) | |
( ctx - > callbacks . stream_message_cb ! = NULL ) | |
( ctx - > callbacks . stream_truncate_cb ! = NULL ) ;
/*
* streaming callbacks
*
* stream_message and stream_truncate callbacks are optional , so we do not
* fail with ERROR when missing , but the wrappers simply do nothing . We
* must set the ReorderBuffer callbacks to something , otherwise the calls
* from there will crash ( we don ' t want to move the checks there ) .
*/
ctx - > reorder - > stream_start = stream_start_cb_wrapper ;
ctx - > reorder - > stream_stop = stream_stop_cb_wrapper ;
ctx - > reorder - > stream_abort = stream_abort_cb_wrapper ;
ctx - > reorder - > stream_commit = stream_commit_cb_wrapper ;
ctx - > reorder - > stream_change = stream_change_cb_wrapper ;
ctx - > reorder - > stream_message = stream_message_cb_wrapper ;
ctx - > reorder - > stream_truncate = stream_truncate_cb_wrapper ;
ctx - > out = makeStringInfo ( ) ;
ctx - > prepare_write = prepare_write ;
ctx - > write = do_write ;
@ -866,6 +916,307 @@ message_cb_wrapper(ReorderBuffer *cache, ReorderBufferTXN *txn,
error_context_stack = errcallback . previous ;
}
static void
stream_start_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
XLogRecPtr first_lsn )
{
LogicalDecodingContext * ctx = cache - > private_data ;
LogicalErrorCallbackState state ;
ErrorContextCallback errcallback ;
Assert ( ! ctx - > fast_forward ) ;
/* We're only supposed to call this when streaming is supported. */
Assert ( ctx - > streaming ) ;
/* Push callback + info on the error context stack */
state . ctx = ctx ;
state . callback_name = " stream_start " ;
state . report_location = first_lsn ;
errcallback . callback = output_plugin_error_callback ;
errcallback . arg = ( void * ) & state ;
errcallback . previous = error_context_stack ;
error_context_stack = & errcallback ;
/* set output state */
ctx - > accept_writes = true ;
ctx - > write_xid = txn - > xid ;
/*
* report this message ' s lsn so replies from clients can give an up2date
* answer . This won ' t ever be enough ( and shouldn ' t be ! ) to confirm
* receipt of this transaction , but it might allow another transaction ' s
* commit to be confirmed with one message .
*/
ctx - > write_location = first_lsn ;
/* in streaming mode, stream_start_cb is required */
if ( ctx - > callbacks . stream_start_cb = = NULL )
ereport ( ERROR ,
( errcode ( ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE ) ,
errmsg ( " logical streaming requires a stream_start_cb callback " ) ) ) ;
ctx - > callbacks . stream_start_cb ( ctx , txn ) ;
/* Pop the error context stack */
error_context_stack = errcallback . previous ;
}
static void
stream_stop_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
XLogRecPtr last_lsn )
{
LogicalDecodingContext * ctx = cache - > private_data ;
LogicalErrorCallbackState state ;
ErrorContextCallback errcallback ;
Assert ( ! ctx - > fast_forward ) ;
/* We're only supposed to call this when streaming is supported. */
Assert ( ctx - > streaming ) ;
/* Push callback + info on the error context stack */
state . ctx = ctx ;
state . callback_name = " stream_stop " ;
state . report_location = last_lsn ;
errcallback . callback = output_plugin_error_callback ;
errcallback . arg = ( void * ) & state ;
errcallback . previous = error_context_stack ;
error_context_stack = & errcallback ;
/* set output state */
ctx - > accept_writes = true ;
ctx - > write_xid = txn - > xid ;
/*
* report this message ' s lsn so replies from clients can give an up2date
* answer . This won ' t ever be enough ( and shouldn ' t be ! ) to confirm
* receipt of this transaction , but it might allow another transaction ' s
* commit to be confirmed with one message .
*/
ctx - > write_location = last_lsn ;
/* in streaming mode, stream_stop_cb is required */
if ( ctx - > callbacks . stream_stop_cb = = NULL )
ereport ( ERROR ,
( errcode ( ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE ) ,
errmsg ( " logical streaming requires a stream_stop_cb callback " ) ) ) ;
ctx - > callbacks . stream_stop_cb ( ctx , txn ) ;
/* Pop the error context stack */
error_context_stack = errcallback . previous ;
}
static void
stream_abort_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
XLogRecPtr abort_lsn )
{
LogicalDecodingContext * ctx = cache - > private_data ;
LogicalErrorCallbackState state ;
ErrorContextCallback errcallback ;
Assert ( ! ctx - > fast_forward ) ;
/* We're only supposed to call this when streaming is supported. */
Assert ( ctx - > streaming ) ;
/* Push callback + info on the error context stack */
state . ctx = ctx ;
state . callback_name = " stream_abort " ;
state . report_location = abort_lsn ;
errcallback . callback = output_plugin_error_callback ;
errcallback . arg = ( void * ) & state ;
errcallback . previous = error_context_stack ;
error_context_stack = & errcallback ;
/* set output state */
ctx - > accept_writes = true ;
ctx - > write_xid = txn - > xid ;
ctx - > write_location = abort_lsn ;
/* in streaming mode, stream_abort_cb is required */
if ( ctx - > callbacks . stream_abort_cb = = NULL )
ereport ( ERROR ,
( errcode ( ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE ) ,
errmsg ( " logical streaming requires a stream_abort_cb callback " ) ) ) ;
ctx - > callbacks . stream_abort_cb ( ctx , txn , abort_lsn ) ;
/* Pop the error context stack */
error_context_stack = errcallback . previous ;
}
static void
stream_commit_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
XLogRecPtr commit_lsn )
{
LogicalDecodingContext * ctx = cache - > private_data ;
LogicalErrorCallbackState state ;
ErrorContextCallback errcallback ;
Assert ( ! ctx - > fast_forward ) ;
/* We're only supposed to call this when streaming is supported. */
Assert ( ctx - > streaming ) ;
/* Push callback + info on the error context stack */
state . ctx = ctx ;
state . callback_name = " stream_commit " ;
state . report_location = txn - > final_lsn ;
errcallback . callback = output_plugin_error_callback ;
errcallback . arg = ( void * ) & state ;
errcallback . previous = error_context_stack ;
error_context_stack = & errcallback ;
/* set output state */
ctx - > accept_writes = true ;
ctx - > write_xid = txn - > xid ;
ctx - > write_location = txn - > end_lsn ;
/* in streaming mode, stream_abort_cb is required */
if ( ctx - > callbacks . stream_commit_cb = = NULL )
ereport ( ERROR ,
( errcode ( ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE ) ,
errmsg ( " logical streaming requires a stream_commit_cb callback " ) ) ) ;
ctx - > callbacks . stream_commit_cb ( ctx , txn , commit_lsn ) ;
/* Pop the error context stack */
error_context_stack = errcallback . previous ;
}
static void
stream_change_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
Relation relation , ReorderBufferChange * change )
{
LogicalDecodingContext * ctx = cache - > private_data ;
LogicalErrorCallbackState state ;
ErrorContextCallback errcallback ;
Assert ( ! ctx - > fast_forward ) ;
/* We're only supposed to call this when streaming is supported. */
Assert ( ctx - > streaming ) ;
/* Push callback + info on the error context stack */
state . ctx = ctx ;
state . callback_name = " stream_change " ;
state . report_location = change - > lsn ;
errcallback . callback = output_plugin_error_callback ;
errcallback . arg = ( void * ) & state ;
errcallback . previous = error_context_stack ;
error_context_stack = & errcallback ;
/* set output state */
ctx - > accept_writes = true ;
ctx - > write_xid = txn - > xid ;
/*
* report this change ' s lsn so replies from clients can give an up2date
* answer . This won ' t ever be enough ( and shouldn ' t be ! ) to confirm
* receipt of this transaction , but it might allow another transaction ' s
* commit to be confirmed with one message .
*/
ctx - > write_location = change - > lsn ;
/* in streaming mode, stream_change_cb is required */
if ( ctx - > callbacks . stream_change_cb = = NULL )
ereport ( ERROR ,
( errcode ( ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE ) ,
errmsg ( " logical streaming requires a stream_change_cb callback " ) ) ) ;
ctx - > callbacks . stream_change_cb ( ctx , txn , relation , change ) ;
/* Pop the error context stack */
error_context_stack = errcallback . previous ;
}
static void
stream_message_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
XLogRecPtr message_lsn , bool transactional ,
const char * prefix , Size message_size , const char * message )
{
LogicalDecodingContext * ctx = cache - > private_data ;
LogicalErrorCallbackState state ;
ErrorContextCallback errcallback ;
Assert ( ! ctx - > fast_forward ) ;
/* We're only supposed to call this when streaming is supported. */
Assert ( ctx - > streaming ) ;
/* this callback is optional */
if ( ctx - > callbacks . stream_message_cb = = NULL )
return ;
/* Push callback + info on the error context stack */
state . ctx = ctx ;
state . callback_name = " stream_message " ;
state . report_location = message_lsn ;
errcallback . callback = output_plugin_error_callback ;
errcallback . arg = ( void * ) & state ;
errcallback . previous = error_context_stack ;
error_context_stack = & errcallback ;
/* set output state */
ctx - > accept_writes = true ;
ctx - > write_xid = txn ! = NULL ? txn - > xid : InvalidTransactionId ;
ctx - > write_location = message_lsn ;
/* do the actual work: call callback */
ctx - > callbacks . stream_message_cb ( ctx , txn , message_lsn , transactional , prefix ,
message_size , message ) ;
/* Pop the error context stack */
error_context_stack = errcallback . previous ;
}
static void
stream_truncate_cb_wrapper ( ReorderBuffer * cache , ReorderBufferTXN * txn ,
int nrelations , Relation relations [ ] ,
ReorderBufferChange * change )
{
LogicalDecodingContext * ctx = cache - > private_data ;
LogicalErrorCallbackState state ;
ErrorContextCallback errcallback ;
Assert ( ! ctx - > fast_forward ) ;
/* We're only supposed to call this when streaming is supported. */
Assert ( ctx - > streaming ) ;
/* this callback is optional */
if ( ! ctx - > callbacks . stream_truncate_cb )
return ;
/* Push callback + info on the error context stack */
state . ctx = ctx ;
state . callback_name = " stream_truncate " ;
state . report_location = change - > lsn ;
errcallback . callback = output_plugin_error_callback ;
errcallback . arg = ( void * ) & state ;
errcallback . previous = error_context_stack ;
error_context_stack = & errcallback ;
/* set output state */
ctx - > accept_writes = true ;
ctx - > write_xid = txn - > xid ;
/*
* report this change ' s lsn so replies from clients can give an up2date
* answer . This won ' t ever be enough ( and shouldn ' t be ! ) to confirm
* receipt of this transaction , but it might allow another transaction ' s
* commit to be confirmed with one message .
*/
ctx - > write_location = change - > lsn ;
ctx - > callbacks . stream_truncate_cb ( ctx , txn , nrelations , relations , change ) ;
/* Pop the error context stack */
error_context_stack = errcallback . previous ;
}
/*
* Set the required catalog xmin horizon for historic snapshots in the current
* replication slot .
Amit Kapila
5 years ago