Alvaro Herrera escribió:
> Hmm, maybe I should be considering a pair of macros instead --
> UTILITY_START_DROP and UTILITY_END_DROP. I'll give this a try. Other
> ideas are welcome.
This seems to work. See attached; I like the result because there's no
clutter and it supports all three cases without a problem.
I also added a new output column to pg_event_trigger_dropped_objects,
"subobject_name", which is NULL except when a column is being dropped,
in which case it contains the column name. Also, the "object type"
column now says "table column" instead of "table" when dropping a
column.
Another question arose in testing: this reports dropping of temp
objects, too, but of course not always: particularly not when temp
objects are dropped at the end of a session (or the beginning of a
session that reuses a previously used temp schema). I find this rather
inconsistent and I wonder if we should instead suppress reporting of
temp objects.
--
Álvaro Herrera http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services
diff --git a/doc/src/sgml/event-trigger.sgml b/doc/src/sgml/event-trigger.sgml
index 71241c8..1e67d86 100644
--- a/doc/src/sgml/event-trigger.sgml
+++ b/doc/src/sgml/event-trigger.sgml
@@ -36,8 +36,8 @@
The <literal>ddl_command_start</> event occurs just before the
execution of a <literal>CREATE</>, <literal>ALTER</>, or <literal>DROP</>
command. As an exception, however, this event does not occur for
- DDL commands targeting shared objects - databases, roles, and tablespaces
- - or for command targeting event triggers themselves. The event trigger
+ DDL commands targeting shared objects — databases, roles, and tablespaces
+ — or for command targeting event triggers themselves. The event trigger
mechanism does not support these object types.
<literal>ddl_command_start</> also occurs just before the execution of a
<literal>SELECT INTO</literal> command, since this is equivalent to
@@ -46,6 +46,16 @@
</para>
<para>
+ To list all objects that have been deleted as part of executing a
+ command, use the set returning
+ function <literal>pg_event_trigger_dropped_objects()</> from
+ your <literal>ddl_command_end</> event trigger code (see
+ <xref linkend="functions-event-triggers">). Note that
+ the trigger is executed after the objects have been deleted from the
+ system catalogs, so it's not possible to look them up anymore.
+ </para>
+
+ <para>
Event triggers (like other functions) cannot be executed in an aborted
transaction. Thus, if a DDL command fails with an error, any associated
<literal>ddl_command_end</> triggers will not be executed. Conversely,
@@ -433,6 +443,11 @@
<entry align="center"><literal>X</literal></entry>
</row>
<row>
+ <entry align="left"><literal>DROP OWNED</literal></entry>
+ <entry align="center"><literal>X</literal></entry>
+ <entry align="center"><literal>X</literal></entry>
+ </row>
+ <row>
<entry align="left"><literal>DROP RULE</literal></entry>
<entry align="center"><literal>X</literal></entry>
<entry align="center"><literal>X</literal></entry>
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 9b7e967..5721d1b 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -15702,4 +15702,54 @@ FOR EACH ROW EXECUTE PROCEDURE suppress_redundant_updates_trigger();
<xref linkend="SQL-CREATETRIGGER">.
</para>
</sect1>
+
+ <sect1 id="functions-event-triggers">
+ <title>Event Trigger Functions</title>
+
+ <indexterm>
+ <primary>pg_event_trigger_dropped_objects</primary>
+ </indexterm>
+
+ <para>
+ Currently <productname>PostgreSQL</> provides one built-in event trigger
+ helper function, <function>pg_event_trigger_dropped_objects</>, which
+ lists all object dropped by the command in whose <literal>ddl_command_end</>
+ event it is called. If the function is run in a context other than a
+ <literal>ddl_command_end</> event trigger function, or if it's run in the
+ <literal>ddl_command_end</> event of a command that does not drop objects,
+ it will return the empty set.
+ </para>
+
+ <para>
+ The <function>pg_event_trigger_dropped_objects</> function can be used
+ in an event trigger like this:
+<programlisting>
+CREATE FUNCTION test_event_trigger_for_drops()
+ RETURNS event_trigger LANGUAGE plpgsql AS $$
+DECLARE
+ obj record;
+BEGIN
+ FOR obj IN SELECT * FROM pg_event_trigger_dropped_objects()
+ LOOP
+ RAISE NOTICE '% dropped object: % %.% %',
+ tg_tag,
+ obj.object_type,
+ obj.schema_name,
+ obj.object_name,
+ obj.subobject_name;
+ END LOOP;
+END
+$$;
+CREATE EVENT TRIGGER test_event_trigger_for_drops
+ ON ddl_command_end
+ EXECUTE PROCEDURE test_event_trigger_for_drops();
+</programlisting>
+ </para>
+
+ <para>
+ For more information about event triggers,
+ see <xref linkend="event-triggers">.
+ </para>
+ </sect1>
+
</chapter>
diff --git a/src/backend/catalog/dependency.c b/src/backend/catalog/dependency.c
index 32f05bb..a91111b 100644
--- a/src/backend/catalog/dependency.c
+++ b/src/backend/catalog/dependency.c
@@ -198,6 +198,7 @@ static bool stack_address_present_add_flags(const ObjectAddress *object,
ObjectAddressStack *stack);
static void getRelationDescription(StringInfo buffer, Oid relid);
static void getOpFamilyDescription(StringInfo buffer, Oid opfid);
+static void getRelationTypeDescription(StringInfo buffer, Oid relid, int32 objectSubId);
/*
@@ -267,6 +268,12 @@ performDeletion(const ObjectAddress *object,
{
ObjectAddress *thisobj = targetObjects->refs + i;
+ if ((!(flags & PERFORM_DELETION_INTERNAL)) &&
+ EventTriggerSupportsObjectType(getObjectClass(thisobj)))
+ {
+ evtrig_sqldrop_add_object(thisobj);
+ }
+
deleteOneObject(thisobj, &depRel, flags);
}
@@ -349,6 +356,12 @@ performMultipleDeletions(const ObjectAddresses *objects,
{
ObjectAddress *thisobj = targetObjects->refs + i;
+ if ((!(flags & PERFORM_DELETION_INTERNAL)) &&
+ EventTriggerSupportsObjectType(getObjectClass(thisobj)))
+ {
+ evtrig_sqldrop_add_object(thisobj);
+ }
+
deleteOneObject(thisobj, &depRel, flags);
}
@@ -366,6 +379,10 @@ performMultipleDeletions(const ObjectAddresses *objects,
* This is currently used only to clean out the contents of a schema
* (namespace): the passed object is a namespace. We normally want this
* to be done silently, so there's an option to suppress NOTICE messages.
+ *
+ * Note we don't fire object drop event triggers here; it would be wrong to do
+ * so for the current only use of this function, but if more callers are added
+ * this might need to be reconsidered.
*/
void
deleteWhatDependsOn(const ObjectAddress *object,
@@ -3107,3 +3124,199 @@ pg_describe_object(PG_FUNCTION_ARGS)
description = getObjectDescription(&address);
PG_RETURN_TEXT_P(cstring_to_text(description));
}
+
+char *
+getObjectTypeDescription(const ObjectAddress *object)
+{
+ StringInfoData buffer;
+
+ initStringInfo(&buffer);
+
+ switch (getObjectClass(object))
+ {
+ case OCLASS_CLASS:
+ getRelationTypeDescription(&buffer, object->objectId,
+ object->objectSubId);
+ break;
+
+ case OCLASS_PROC:
+ appendStringInfo(&buffer, "function");
+ break;
+
+ case OCLASS_TYPE:
+ appendStringInfo(&buffer, "type");
+ break;
+
+ case OCLASS_CAST:
+ appendStringInfo(&buffer, "cast");
+ break;
+
+ case OCLASS_COLLATION:
+ appendStringInfo(&buffer, "collation");
+ break;
+
+ case OCLASS_CONSTRAINT:
+ appendStringInfo(&buffer, "constraint");
+ break;
+
+ case OCLASS_CONVERSION:
+ appendStringInfo(&buffer, "conversion");
+ break;
+
+ case OCLASS_DEFAULT:
+ appendStringInfo(&buffer, "default value");
+ break;
+
+ case OCLASS_LANGUAGE:
+ appendStringInfo(&buffer, "language");
+ break;
+
+ case OCLASS_LARGEOBJECT:
+ appendStringInfo(&buffer, "large object");
+ break;
+
+ case OCLASS_OPERATOR:
+ appendStringInfo(&buffer, "operator");
+ break;
+
+ case OCLASS_OPCLASS:
+ appendStringInfo(&buffer, "operator class");
+ break;
+
+ case OCLASS_OPFAMILY:
+ appendStringInfo(&buffer, "operator family");
+ break;
+
+ case OCLASS_AMOP:
+ appendStringInfo(&buffer, "operator of access method");
+ break;
+
+ case OCLASS_AMPROC:
+ appendStringInfo(&buffer, "function of access method");
+ break;
+
+ case OCLASS_REWRITE:
+ appendStringInfo(&buffer, "rule");
+ break;
+
+ case OCLASS_TRIGGER:
+ appendStringInfo(&buffer, "trigger");
+ break;
+
+ case OCLASS_SCHEMA:
+ appendStringInfo(&buffer, "schema");
+ break;
+
+ case OCLASS_TSPARSER:
+ appendStringInfo(&buffer, "text search parser");
+ break;
+
+ case OCLASS_TSDICT:
+ appendStringInfo(&buffer, "text search dictionary");
+ break;
+
+ case OCLASS_TSTEMPLATE:
+ appendStringInfo(&buffer, "text search template");
+ break;
+
+ case OCLASS_TSCONFIG:
+ appendStringInfo(&buffer, "text search configuration");
+ break;
+
+ case OCLASS_ROLE:
+ appendStringInfo(&buffer, "role");
+ break;
+
+ case OCLASS_DATABASE:
+ appendStringInfo(&buffer, "database");
+ break;
+
+ case OCLASS_TBLSPACE:
+ appendStringInfo(&buffer, "tablespace");
+ break;
+
+ case OCLASS_FDW:
+ appendStringInfo(&buffer, "foreign-data wrapper");
+ break;
+
+ case OCLASS_FOREIGN_SERVER:
+ appendStringInfo(&buffer, "server");
+ break;
+
+ case OCLASS_USER_MAPPING:
+ appendStringInfo(&buffer, "user mapping");
+ break;
+
+ case OCLASS_DEFACL:
+ /* XXX do we need more detail here? */
+ appendStringInfo(&buffer, "default ACL");
+ break;
+
+ case OCLASS_EXTENSION:
+ appendStringInfo(&buffer, "extension");
+ break;
+
+ case OCLASS_EVENT_TRIGGER:
+ appendStringInfo(&buffer, "event trigger");
+ break;
+
+ default:
+ appendStringInfo(&buffer, "unrecognized object type");
+ break;
+ }
+
+ return buffer.data;
+}
+
+/*
+ * subroutine for getObjectTypeDescription: describe a relation type
+ */
+static void
+getRelationTypeDescription(StringInfo buffer, Oid relid, int32 objectSubId)
+{
+ HeapTuple relTup;
+ Form_pg_class relForm;
+
+ relTup = SearchSysCache1(RELOID,
+ ObjectIdGetDatum(relid));
+ if (!HeapTupleIsValid(relTup))
+ elog(ERROR, "cache lookup failed for relation %u", relid);
+ relForm = (Form_pg_class) GETSTRUCT(relTup);
+
+ switch (relForm->relkind)
+ {
+ case RELKIND_RELATION:
+ appendStringInfo(buffer, "table");
+ break;
+ case RELKIND_INDEX:
+ appendStringInfo(buffer, "index");
+ break;
+ case RELKIND_SEQUENCE:
+ appendStringInfo(buffer, "sequence");
+ break;
+ case RELKIND_TOASTVALUE:
+ appendStringInfo(buffer, "toast table");
+ break;
+ case RELKIND_VIEW:
+ appendStringInfo(buffer, "view");
+ break;
+ case RELKIND_MATVIEW:
+ appendStringInfo(buffer, "materialized view");
+ break;
+ case RELKIND_COMPOSITE_TYPE:
+ appendStringInfo(buffer, "composite type");
+ break;
+ case RELKIND_FOREIGN_TABLE:
+ appendStringInfo(buffer, "foreign table");
+ break;
+ default:
+ /* shouldn't get here */
+ appendStringInfo(buffer, "relation");
+ break;
+ }
+
+ if (objectSubId != 0)
+ appendStringInfo(buffer, " column");
+
+ ReleaseSysCache(relTup);
+}
diff --git a/src/backend/catalog/objectaddress.c b/src/backend/catalog/objectaddress.c
index 6f60d7c..04f6893 100644
--- a/src/backend/catalog/objectaddress.c
+++ b/src/backend/catalog/objectaddress.c
@@ -1345,6 +1345,24 @@ get_object_aclkind(Oid class_id)
}
/*
+ * Return whether we have useful data for the given object class in the
+ * ObjectProperty table.
+ */
+bool
+is_objectclass_supported(Oid class_id)
+{
+ int index;
+
+ for (index = 0; index < lengthof(ObjectProperty); index++)
+ {
+ if (ObjectProperty[index].class_oid == class_id)
+ return true;
+ }
+
+ return false;
+}
+
+/*
* Find ObjectProperty structure by class_id.
*/
static ObjectPropertyType *
diff --git a/src/backend/commands/alter.c b/src/backend/commands/alter.c
index 416a068..8a88c91 100644
--- a/src/backend/commands/alter.c
+++ b/src/backend/commands/alter.c
@@ -748,58 +748,6 @@ ExecAlterOwnerStmt(AlterOwnerStmt *stmt)
}
/*
- * Return a copy of the tuple for the object with the given object OID, from
- * the given catalog (which must have been opened by the caller and suitably
- * locked). NULL is returned if the OID is not found.
- *
- * We try a syscache first, if available.
- *
- * XXX this function seems general in possible usage. Given sufficient callers
- * elsewhere, we should consider moving it to a more appropriate place.
- */
-static HeapTuple
-get_catalog_object_by_oid(Relation catalog, Oid objectId)
-{
- HeapTuple tuple;
- Oid classId = RelationGetRelid(catalog);
- int oidCacheId = get_object_catcache_oid(classId);
-
- if (oidCacheId > 0)
- {
- tuple = SearchSysCacheCopy1(oidCacheId, ObjectIdGetDatum(objectId));
- if (!HeapTupleIsValid(tuple)) /* should not happen */
- return NULL;
- }
- else
- {
- Oid oidIndexId = get_object_oid_index(classId);
- SysScanDesc scan;
- ScanKeyData skey;
-
- Assert(OidIsValid(oidIndexId));
-
- ScanKeyInit(&skey,
- ObjectIdAttributeNumber,
- BTEqualStrategyNumber, F_OIDEQ,
- ObjectIdGetDatum(objectId));
-
- scan = systable_beginscan(catalog, oidIndexId, true,
- SnapshotNow, 1, &skey);
- tuple = systable_getnext(scan);
- if (!HeapTupleIsValid(tuple))
- {
- systable_endscan(scan);
- return NULL;
- }
- tuple = heap_copytuple(tuple);
-
- systable_endscan(scan);
- }
-
- return tuple;
-}
-
-/*
* Generic function to change the ownership of a given object, for simple
* cases (won't work for tables, nor other cases where we need to do more than
* change the ownership column of a single catalog entry).
diff --git a/src/backend/commands/event_trigger.c b/src/backend/commands/event_trigger.c
index 596178f..d467fb8 100644
--- a/src/backend/commands/event_trigger.c
+++ b/src/backend/commands/event_trigger.c
@@ -25,6 +25,7 @@
#include "commands/dbcommands.h"
#include "commands/event_trigger.h"
#include "commands/trigger.h"
+#include "funcapi.h"
#include "parser/parse_func.h"
#include "pgstat.h"
#include "miscadmin.h"
@@ -39,6 +40,10 @@
#include "utils/syscache.h"
#include "tcop/utility.h"
+/* -- Globally visible state -- */
+/* list of objects dropped by current command */
+slist_head SQLDropList = SLIST_STATIC_INIT(SQLDropList);
+
typedef struct
{
const char *obtypename;
@@ -89,6 +94,17 @@ static event_trigger_support_data event_trigger_support[] = {
{ NULL, false }
};
+/* Support for dropped objects */
+typedef struct SQLDropObject
+{
+ ObjectAddress address;
+ char *objname;
+ char *subobjname;
+ char *schemaname;
+ char *objecttype;
+ slist_node next;
+} SQLDropObject;
+
static void AlterEventTriggerOwner_internal(Relation rel,
HeapTuple tup,
Oid newOwnerId);
@@ -151,8 +167,12 @@ CreateEventTrigger(CreateEventTrigStmt *stmt)
}
/* Validate tag list, if any. */
- if (strcmp(stmt->eventname, "ddl_command_start") == 0 && tags != NULL)
+ if ((strcmp(stmt->eventname, "ddl_command_start") == 0 ||
+ strcmp(stmt->eventname, "ddl_command_end") == 0)
+ && tags != NULL)
+ {
validate_ddl_tags("tag", tags);
+ }
/*
* Give user a nice error message if an event trigger of the same name
@@ -220,7 +240,8 @@ check_ddl_tag(const char *tag)
pg_strcasecmp(tag, "SELECT INTO") == 0 ||
pg_strcasecmp(tag, "REFRESH MATERIALIZED VIEW") == 0 ||
pg_strcasecmp(tag, "ALTER DEFAULT PRIVILEGES") == 0 ||
- pg_strcasecmp(tag, "ALTER LARGE OBJECT") == 0)
+ pg_strcasecmp(tag, "ALTER LARGE OBJECT") == 0 ||
+ pg_strcasecmp(tag, "DROP OWNED") == 0)
return EVENT_TRIGGER_COMMAND_TAG_OK;
/*
@@ -827,3 +848,215 @@ EventTriggerSupportsObjectType(ObjectType obtype)
}
return true;
}
+
+/*
+ * Support for dropped objects information on event trigger functions.
+ *
+ * We keep the list of objects dropped by the current command in SQLDropList
+ * (comprising SQLDropObject items). Each command that might drop objects
+ * saves the current list in a local variable, initializes a new empty list and
+ * does the dependency.c dance to drop objects, which populates the list; when
+ * the event triggers are invoked they can consume the list via
+ * pg_event_trigger_dropped_objects(). When the command finishes, the list is
+ * cleared and the original list is restored. This is to support the case that
+ * an event trigger function drops objects "reentrantly".
+ */
+
+/*
+ * Initialize state of objects dropped
+ */
+void
+EventTriggerInitializeDrop(slist_head *save_objlist)
+{
+ /* save previous state in local vars of caller, for later restore */
+ *save_objlist = SQLDropList;
+
+ slist_init(&SQLDropList);
+}
+
+/*
+ * Restore state after running a command that drops objects; free memory from a
+ * list we may have created.
+ */
+void
+EventTriggerFinalizeDrop(slist_head save_objlist)
+{
+ slist_mutable_iter iter;
+
+ slist_foreach_modify(iter, &SQLDropList)
+ {
+ SQLDropObject *obj = slist_container(SQLDropObject, next, iter.cur);
+
+ if (obj->objname)
+ pfree(obj->objname);
+ if (obj->subobjname)
+ pfree(obj->subobjname);
+ if (obj->schemaname)
+ pfree(obj->schemaname);
+ pfree(obj);
+ }
+
+ SQLDropList = save_objlist;
+}
+
+/*
+ * Register one object as being dropped by the current command.
+ *
+ * XXX do we need to think about memory context these things are stored in?
+ */
+void
+evtrig_sqldrop_add_object(ObjectAddress *object)
+{
+ SQLDropObject *obj;
+
+ Assert(EventTriggerSupportsObjectType(getObjectClass(object)));
+
+ obj = palloc0(sizeof(SQLDropObject));
+ obj->address = *object;
+
+ /*
+ * Obtain object and schema names from the object's catalog tuple, if one
+ * exists.
+ */
+ if (is_objectclass_supported(obj->address.classId))
+ {
+ Relation catalog;
+ HeapTuple tuple;
+
+ catalog = heap_open(obj->address.classId, AccessShareLock);
+ tuple = get_catalog_object_by_oid(catalog, obj->address.objectId);
+ if (tuple)
+ {
+ AttrNumber attnum;
+ Datum datum;
+ bool isnull;
+
+ attnum = get_object_attnum_name(obj->address.classId);
+ if (attnum != InvalidAttrNumber)
+ {
+ datum = heap_getattr(tuple, attnum,
+ RelationGetDescr(catalog), &isnull);
+ if (!isnull)
+ obj->objname = pstrdup(NameStr(*DatumGetName(datum)));
+ }
+
+ attnum = get_object_attnum_namespace(obj->address.classId);
+ if (attnum != InvalidAttrNumber)
+ {
+ datum = heap_getattr(tuple, attnum,
+ RelationGetDescr(catalog), &isnull);
+ if (!isnull)
+ obj->schemaname = get_namespace_name(DatumGetObjectId(datum));
+ }
+ }
+
+ /* add a column name, if present */
+ if (obj->address.objectSubId != 0)
+ {
+ /* must be a relation of some kind */
+ Assert(RelationGetRelid(catalog) == RelationRelationId);
+
+ obj->subobjname = get_attname(obj->address.objectId,
+ obj->address.objectSubId);
+ }
+
+ heap_close(catalog, AccessShareLock);
+ }
+
+ /* and object type, too */
+ obj->objecttype = getObjectTypeDescription(&obj->address);
+
+ slist_push_head(&SQLDropList, &obj->next);
+}
+
+/*
+ * pg_event_trigger_dropped_objects
+ *
+ * Make the list of dropped objects available to the user function run by the
+ * Event Trigger.
+ */
+Datum
+pg_event_trigger_dropped_objects(PG_FUNCTION_ARGS)
+{
+ ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+ TupleDesc tupdesc;
+ Tuplestorestate *tupstore;
+ MemoryContext per_query_ctx;
+ MemoryContext oldcontext;
+ slist_iter iter;
+
+ /* check to see if caller supports us returning a tuplestore */
+ if (rsinfo == NULL || !IsA(rsinfo, ReturnSetInfo))
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("set-valued function called in context that cannot accept a set")));
+ if (!(rsinfo->allowedModes & SFRM_Materialize))
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("materialize mode required, but it is not allowed in this context")));
+
+ /* Build a tuple descriptor for our result type */
+ if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
+ elog(ERROR, "return type must be a row type");
+
+ /* Build tuplestore to hold the result rows */
+ per_query_ctx = rsinfo->econtext->ecxt_per_query_memory;
+ oldcontext = MemoryContextSwitchTo(per_query_ctx);
+
+ tupstore = tuplestore_begin_heap(true, false, work_mem);
+ rsinfo->returnMode = SFRM_Materialize;
+ rsinfo->setResult = tupstore;
+ rsinfo->setDesc = tupdesc;
+
+ MemoryContextSwitchTo(oldcontext);
+
+ slist_foreach(iter, &SQLDropList)
+ {
+ SQLDropObject *obj;
+ int i = 0;
+ Datum values[7];
+ bool nulls[7];
+
+ obj = slist_container(SQLDropObject, next, iter.cur);
+
+ MemSet(values, 0, sizeof(values));
+ MemSet(nulls, 0, sizeof(nulls));
+
+ /* classid */
+ values[i++] = ObjectIdGetDatum(obj->address.classId);
+
+ /* objid */
+ values[i++] = ObjectIdGetDatum(obj->address.objectId);
+
+ /* objsubid */
+ values[i++] = Int32GetDatum(obj->address.objectSubId);
+
+ /* object type */
+ values[i++] = CStringGetTextDatum(obj->objecttype);
+
+ /* objname */
+ if (obj->objname)
+ values[i++] = CStringGetTextDatum(obj->objname);
+ else
+ nulls[i++] = true;
+
+ /* subobjname */
+ if (obj->subobjname)
+ values[i++] = CStringGetTextDatum(obj->subobjname);
+ else
+ nulls[i++] = true;
+
+ /* schemaname */
+ if (obj->schemaname)
+ values[i++] = CStringGetTextDatum(obj->schemaname);
+ else
+ nulls[i++] = true;
+
+ tuplestore_putvalues(tupstore, tupdesc, values, nulls);
+ }
+
+ /* clean up and return the tuplestore */
+ tuplestore_donestoring(tupstore);
+
+ return (Datum) 0;
+}
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index a1c03f1..66839d8 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -370,6 +370,52 @@ ProcessUtility(Node *parsetree,
} \
} while (0)
+/*
+ * UTILITY_BEGIN_DROP and UTILITY_END_DROP are a pair of macros to enclose a
+ * code fragment that executes a command that may drop database objects, so
+ * that the event trigger environment is appropriately setup.
+ *
+ * Note these macros will call EventTriggerDDLCommandEnd if the object type is
+ * supported; caller must make sure to call EventTriggerDDLCommandStart by
+ * itself.
+ */
+#define UTILITY_BEGIN_DROP(isCompleteQuery, has_objtype, objtype) \
+ do { \
+ slist_head _save_objlist; \
+ bool _supported; \
+ bool _isComplete = isCompleteQuery; \
+ \
+ _supported = has_objtype ? EventTriggerSupportsObjectType(objtype) : true; \
+ \
+ if (_isComplete) \
+ { \
+ EventTriggerInitializeDrop(&_save_objlist); \
+ } \
+ PG_TRY(); \
+ {
+
+#define UTILITY_END_DROP(parsetree) \
+ } \
+ if (_isComplete && _supported) \
+ { \
+ EventTriggerDDLCommandEnd(parsetree); \
+ } \
+ \
+ PG_CATCH(); \
+ { \
+ if (_isComplete && _supported) \
+ { \
+ EventTriggerFinalizeDrop(_save_objlist); \
+ } \
+ PG_RE_THROW(); \
+ } \
+ PG_END_TRY(); \
+ if (_isComplete && _supported) \
+ { \
+ EventTriggerFinalizeDrop(_save_objlist); \
+ } \
+ } while (0)
+
void
standard_ProcessUtility(Node *parsetree,
const char *queryString,
@@ -704,6 +750,8 @@ standard_ProcessUtility(Node *parsetree,
&& EventTriggerSupportsObjectType(stmt->removeType))
EventTriggerDDLCommandStart(parsetree);
+ UTILITY_BEGIN_DROP(isCompleteQuery, true, stmt->removeType);
+
switch (stmt->removeType)
{
case OBJECT_INDEX:
@@ -724,9 +772,7 @@ standard_ProcessUtility(Node *parsetree,
break;
}
- if (isCompleteQuery
- && EventTriggerSupportsObjectType(stmt->removeType))
- EventTriggerDDLCommandEnd(parsetree);
+ UTILITY_END_DROP(parsetree);
break;
}
@@ -826,6 +872,8 @@ standard_ProcessUtility(Node *parsetree,
/* Run parse analysis ... */
stmts = transformAlterTableStmt(atstmt, queryString);
+ UTILITY_BEGIN_DROP(isCompleteQuery, true, OBJECT_TABLE);
+
/* ... and do it */
foreach(l, stmts)
{
@@ -851,6 +899,8 @@ standard_ProcessUtility(Node *parsetree,
if (lnext(l) != NULL)
CommandCounterIncrement();
}
+
+ UTILITY_END_DROP(parsetree);
}
else
ereport(NOTICE,
@@ -1248,8 +1298,12 @@ standard_ProcessUtility(Node *parsetree,
break;
case T_DropOwnedStmt:
- /* no event triggers for global objects */
+ if (isCompleteQuery)
+ EventTriggerDDLCommandStart(parsetree);
+
+ UTILITY_BEGIN_DROP(isCompleteQuery, false, 0);
DropOwnedObjects((DropOwnedStmt *) parsetree);
+ UTILITY_END_DROP(parsetree);
break;
case T_ReassignOwnedStmt:
diff --git a/src/backend/utils/cache/lsyscache.c b/src/backend/utils/cache/lsyscache.c
index 5865962..7f25de4 100644
--- a/src/backend/utils/cache/lsyscache.c
+++ b/src/backend/utils/cache/lsyscache.c
@@ -18,6 +18,7 @@
#include "access/hash.h"
#include "access/htup_details.h"
#include "access/nbtree.h"
+#include "access/sysattr.h"
#include "bootstrap/bootstrap.h"
#include "catalog/pg_amop.h"
#include "catalog/pg_amproc.h"
@@ -40,6 +41,7 @@
#include "utils/lsyscache.h"
#include "utils/rel.h"
#include "utils/syscache.h"
+#include "utils/tqual.h"
#include "utils/typcache.h"
/* Hook for plugins to get control in get_attavgwidth() */
@@ -2926,3 +2928,54 @@ get_range_subtype(Oid rangeOid)
else
return InvalidOid;
}
+
+/* ------------- GENERIC -------------- */
+
+/*
+ * Return a copy of the tuple for the object with the given object OID, from
+ * the given catalog (which must have been opened by the caller and suitably
+ * locked). NULL is returned if the OID is not found.
+ *
+ * We try a syscache first, if available.
+ */
+HeapTuple
+get_catalog_object_by_oid(Relation catalog, Oid objectId)
+{
+ HeapTuple tuple;
+ Oid classId = RelationGetRelid(catalog);
+ int oidCacheId = get_object_catcache_oid(classId);
+
+ if (oidCacheId > 0)
+ {
+ tuple = SearchSysCacheCopy1(oidCacheId, ObjectIdGetDatum(objectId));
+ if (!HeapTupleIsValid(tuple)) /* should not happen */
+ return NULL;
+ }
+ else
+ {
+ Oid oidIndexId = get_object_oid_index(classId);
+ SysScanDesc scan;
+ ScanKeyData skey;
+
+ Assert(OidIsValid(oidIndexId));
+
+ ScanKeyInit(&skey,
+ ObjectIdAttributeNumber,
+ BTEqualStrategyNumber, F_OIDEQ,
+ ObjectIdGetDatum(objectId));
+
+ scan = systable_beginscan(catalog, oidIndexId, true,
+ SnapshotNow, 1, &skey);
+ tuple = systable_getnext(scan);
+ if (!HeapTupleIsValid(tuple))
+ {
+ systable_endscan(scan);
+ return NULL;
+ }
+ tuple = heap_copytuple(tuple);
+
+ systable_endscan(scan);
+ }
+
+ return tuple;
+}
diff --git a/src/include/catalog/dependency.h b/src/include/catalog/dependency.h
index 8e0837f..106d8fb 100644
--- a/src/include/catalog/dependency.h
+++ b/src/include/catalog/dependency.h
@@ -179,6 +179,8 @@ extern ObjectClass getObjectClass(const ObjectAddress *object);
extern char *getObjectDescription(const ObjectAddress *object);
extern char *getObjectDescriptionOids(Oid classid, Oid objid);
+extern char *getObjectTypeDescription(const ObjectAddress *object);
+
extern ObjectAddresses *new_object_addresses(void);
extern void add_exact_object_address(const ObjectAddress *object,
diff --git a/src/include/catalog/objectaddress.h b/src/include/catalog/objectaddress.h
index ffaf4ea..8a34b50 100644
--- a/src/include/catalog/objectaddress.h
+++ b/src/include/catalog/objectaddress.h
@@ -38,6 +38,7 @@ extern void check_object_ownership(Oid roleid,
extern Oid get_object_namespace(const ObjectAddress *address);
+extern bool is_objectclass_supported(Oid class_id);
extern Oid get_object_oid_index(Oid class_id);
extern int get_object_catcache_oid(Oid class_id);
extern int get_object_catcache_name(Oid class_id);
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 0e26ebf..09b5e61 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -4682,6 +4682,9 @@ DATA(insert OID = 3473 ( spg_range_quad_leaf_consistent PGNSP PGUID 12 1 0 0 0
DESCR("SP-GiST support for quad tree over range");
+/* event triggers */
+DATA(insert OID = 3566 ( pg_event_trigger_dropped_objects PGNSP PGUID 12 10 100 0 0 f f f f t t s 0 0 2249 "" "{26,26,26,25,25,25,25}" "{o,o,o,o,o,o,o}" "{classid, objid, objsubid, object_type, object_name, subobject_name, schema_name}" _null_ pg_event_trigger_dropped_objects _null_ _null_ _null_ ));
+DESCR("list objects dropped by the current command");
/*
* Symbolic values for provolatile column: these indicate whether the result
* of a function is dependent *only* on the values of its explicit arguments,
diff --git a/src/include/commands/event_trigger.h b/src/include/commands/event_trigger.h
index 74c150b..2730e7a 100644
--- a/src/include/commands/event_trigger.h
+++ b/src/include/commands/event_trigger.h
@@ -13,7 +13,10 @@
#ifndef EVENT_TRIGGER_H
#define EVENT_TRIGGER_H
+#include "catalog/dependency.h"
+#include "catalog/objectaddress.h"
#include "catalog/pg_event_trigger.h"
+#include "lib/ilist.h"
#include "nodes/parsenodes.h"
typedef struct EventTriggerData
@@ -43,4 +46,8 @@ extern bool EventTriggerSupportsObjectType(ObjectType obtype);
extern void EventTriggerDDLCommandStart(Node *parsetree);
extern void EventTriggerDDLCommandEnd(Node *parsetree);
+extern void EventTriggerInitializeDrop(slist_head *save_objlist);
+extern void EventTriggerFinalizeDrop(slist_head save_objlist);
+extern void evtrig_sqldrop_add_object(ObjectAddress *object);
+
#endif /* EVENT_TRIGGER_H */
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index c0debe4..785d1de 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -1147,6 +1147,9 @@ extern Datum pg_describe_object(PG_FUNCTION_ARGS);
/* commands/constraint.c */
extern Datum unique_key_recheck(PG_FUNCTION_ARGS);
+/* commands/event_trigger.c */
+extern Datum pg_event_trigger_dropped_objects(PG_FUNCTION_ARGS);
+
/* commands/extension.c */
extern Datum pg_available_extensions(PG_FUNCTION_ARGS);
extern Datum pg_available_extension_versions(PG_FUNCTION_ARGS);
diff --git a/src/include/utils/lsyscache.h b/src/include/utils/lsyscache.h
index 49f459a..dfa6eb7 100644
--- a/src/include/utils/lsyscache.h
+++ b/src/include/utils/lsyscache.h
@@ -16,6 +16,7 @@
#include "access/attnum.h"
#include "access/htup.h"
#include "nodes/pg_list.h"
+#include "utils/relcache.h"
/* Result list element for get_op_btree_interpretation */
typedef struct OpBtreeInterpretation
@@ -152,6 +153,7 @@ extern void free_attstatsslot(Oid atttype,
float4 *numbers, int nnumbers);
extern char *get_namespace_name(Oid nspid);
extern Oid get_range_subtype(Oid rangeOid);
+extern HeapTuple get_catalog_object_by_oid(Relation catalog, Oid objectId);
#define type_is_array(typid) (get_element_type(typid) != InvalidOid)
/* type_is_array_domain accepts both plain arrays and domains over arrays */
diff --git a/src/test/regress/expected/event_trigger.out b/src/test/regress/expected/event_trigger.out
index bf020de..264bbb3 100644
--- a/src/test/regress/expected/event_trigger.out
+++ b/src/test/regress/expected/event_trigger.out
@@ -93,11 +93,129 @@ ERROR: event trigger "regress_event_trigger" does not exist
drop role regression_bob;
ERROR: role "regression_bob" cannot be dropped because some objects depend on it
DETAIL: owner of event trigger regress_event_trigger3
+-- cleanup before next test
-- these are all OK; the second one should emit a NOTICE
drop event trigger if exists regress_event_trigger2;
drop event trigger if exists regress_event_trigger2;
NOTICE: event trigger "regress_event_trigger2" does not exist, skipping
drop event trigger regress_event_trigger3;
drop event trigger regress_event_trigger_end;
-drop function test_event_trigger();
+\dy
+ List of event triggers
+ Name | Event | Owner | Enabled | Procedure | Tags
+------+-------+-------+---------+-----------+------
+(0 rows)
+
+-- test support for dropped objects
+CREATE SCHEMA schema_one authorization regression_bob;
+CREATE SCHEMA schema_two authorization regression_bob;
+CREATE SCHEMA audit_tbls authorization regression_bob;
+SET SESSION AUTHORIZATION regression_bob;
+CREATE TABLE schema_one.table_one(a int);
+CREATE TABLE schema_one.table_two(a int);
+CREATE TABLE schema_one.table_three(a int);
+CREATE TABLE audit_tbls.table_two(the_value schema_one.table_two);
+CREATE TABLE schema_two.table_two(a int);
+CREATE TABLE schema_two.table_three(a int, b text);
+CREATE TABLE audit_tbls.table_three(the_value schema_two.table_three);
+RESET SESSION AUTHORIZATION;
+CREATE TABLE dropped_objects (type text,
+ schema text,
+ object text,
+ subobject text,
+ curr_user text,
+ sess_user text);
+CREATE OR REPLACE FUNCTION test_evtrig_dropped_objects() RETURNS event_trigger
+LANGUAGE plpgsql AS $$
+DECLARE
+ obj record;
+BEGIN
+ FOR obj IN SELECT * FROM pg_event_trigger_dropped_objects()
+ LOOP
+ IF obj.object_type = 'table' THEN
+ EXECUTE format('DROP TABLE IF EXISTS audit_tbls.%s',
+ obj.object_name);
+ END IF;
+
+ INSERT INTO dropped_objects
+ (type, schema, object, subobject, curr_user, sess_user) VALUES
+ (obj.object_type, obj.schema_name, obj.object_name,
+ obj.subobject_name, current_user, session_user);
+ END LOOP;
+END
+$$;
+CREATE EVENT TRIGGER regress_event_trigger_drop_objects ON ddl_command_end
+ WHEN TAG IN ('drop table', 'drop function', 'drop view',
+ 'drop owned', 'drop schema', 'alter table')
+ EXECUTE PROCEDURE test_evtrig_dropped_objects();
+ALTER TABLE schema_one.table_one DROP COLUMN a;
+DROP SCHEMA schema_one, schema_two CASCADE;
+NOTICE: drop cascades to 7 other objects
+DETAIL: drop cascades to table schema_two.table_two
+drop cascades to table schema_two.table_three
+drop cascades to table audit_tbls.table_three column the_value
+drop cascades to table schema_one.table_one
+drop cascades to table schema_one.table_two
+drop cascades to table audit_tbls.table_two column the_value
+drop cascades to table schema_one.table_three
+NOTICE: table "table_two" does not exist, skipping
+CONTEXT: SQL statement "DROP TABLE IF EXISTS audit_tbls.table_two"
+PL/pgSQL function test_evtrig_dropped_objects() line 8 at EXECUTE statement
+SQL statement "DROP TABLE IF EXISTS audit_tbls.table_two"
+PL/pgSQL function test_evtrig_dropped_objects() line 8 at EXECUTE statement
+NOTICE: table "table_three" does not exist, skipping
+CONTEXT: SQL statement "DROP TABLE IF EXISTS audit_tbls.table_three"
+PL/pgSQL function test_evtrig_dropped_objects() line 8 at EXECUTE statement
+SQL statement "DROP TABLE IF EXISTS audit_tbls.table_three"
+PL/pgSQL function test_evtrig_dropped_objects() line 8 at EXECUTE statement
+NOTICE: table "table_one" does not exist, skipping
+CONTEXT: SQL statement "DROP TABLE IF EXISTS audit_tbls.table_one"
+PL/pgSQL function test_evtrig_dropped_objects() line 8 at EXECUTE statement
+NOTICE: table "table_two" does not exist, skipping
+CONTEXT: SQL statement "DROP TABLE IF EXISTS audit_tbls.table_two"
+PL/pgSQL function test_evtrig_dropped_objects() line 8 at EXECUTE statement
+NOTICE: table "table_three" does not exist, skipping
+CONTEXT: SQL statement "DROP TABLE IF EXISTS audit_tbls.table_three"
+PL/pgSQL function test_evtrig_dropped_objects() line 8 at EXECUTE statement
+SELECT * FROM dropped_objects WHERE schema IS NULL OR schema <> 'pg_toast';
+ type | schema | object | subobject | curr_user | sess_user
+--------------+------------+--------------+-----------+-----------+-----------
+ table column | schema_one | table_one | a | alvherre | alvherre
+ schema | | schema_two | | alvherre | alvherre
+ table | audit_tbls | table_two | | alvherre | alvherre
+ type | audit_tbls | table_two | | alvherre | alvherre
+ type | audit_tbls | _table_two | | alvherre | alvherre
+ table | schema_two | table_two | | alvherre | alvherre
+ type | schema_two | table_two | | alvherre | alvherre
+ type | schema_two | _table_two | | alvherre | alvherre
+ table | audit_tbls | table_three | | alvherre | alvherre
+ type | audit_tbls | table_three | | alvherre | alvherre
+ type | audit_tbls | _table_three | | alvherre | alvherre
+ table | schema_two | table_three | | alvherre | alvherre
+ type | schema_two | table_three | | alvherre | alvherre
+ type | schema_two | _table_three | | alvherre | alvherre
+ table column | audit_tbls | table_three | the_value | alvherre | alvherre
+ schema | | schema_one | | alvherre | alvherre
+ table | schema_one | table_one | | alvherre | alvherre
+ type | schema_one | table_one | | alvherre | alvherre
+ type | schema_one | _table_one | | alvherre | alvherre
+ table | schema_one | table_two | | alvherre | alvherre
+ type | schema_one | table_two | | alvherre | alvherre
+ type | schema_one | _table_two | | alvherre | alvherre
+ table column | audit_tbls | table_two | the_value | alvherre | alvherre
+ table | schema_one | table_three | | alvherre | alvherre
+ type | schema_one | table_three | | alvherre | alvherre
+ type | schema_one | _table_three | | alvherre | alvherre
+(26 rows)
+
+drop owned by regression_bob;
+SELECT * FROM dropped_objects WHERE type = 'schema';
+ type | schema | object | subobject | curr_user | sess_user
+--------+--------+------------+-----------+-----------+-----------
+ schema | | schema_two | | alvherre | alvherre
+ schema | | schema_one | | alvherre | alvherre
+ schema | | audit_tbls | | alvherre | alvherre
+(3 rows)
+
drop role regression_bob;
+DROP EVENT TRIGGER regress_event_trigger_drop_objects;
diff --git a/src/test/regress/sql/event_trigger.sql b/src/test/regress/sql/event_trigger.sql
index a07dcd7..0c5e7db 100644
--- a/src/test/regress/sql/event_trigger.sql
+++ b/src/test/regress/sql/event_trigger.sql
@@ -97,10 +97,71 @@ drop event trigger regress_event_trigger;
-- should fail, regression_bob owns regress_event_trigger2/3
drop role regression_bob;
+-- cleanup before next test
-- these are all OK; the second one should emit a NOTICE
drop event trigger if exists regress_event_trigger2;
drop event trigger if exists regress_event_trigger2;
drop event trigger regress_event_trigger3;
drop event trigger regress_event_trigger_end;
-drop function test_event_trigger();
+\dy
+
+-- test support for dropped objects
+CREATE SCHEMA schema_one authorization regression_bob;
+CREATE SCHEMA schema_two authorization regression_bob;
+CREATE SCHEMA audit_tbls authorization regression_bob;
+SET SESSION AUTHORIZATION regression_bob;
+
+CREATE TABLE schema_one.table_one(a int);
+CREATE TABLE schema_one.table_two(a int);
+CREATE TABLE schema_one.table_three(a int);
+CREATE TABLE audit_tbls.table_two(the_value schema_one.table_two);
+
+CREATE TABLE schema_two.table_two(a int);
+CREATE TABLE schema_two.table_three(a int, b text);
+CREATE TABLE audit_tbls.table_three(the_value schema_two.table_three);
+
+RESET SESSION AUTHORIZATION;
+
+CREATE TABLE dropped_objects (type text,
+ schema text,
+ object text,
+ subobject text,
+ curr_user text,
+ sess_user text);
+
+CREATE OR REPLACE FUNCTION test_evtrig_dropped_objects() RETURNS event_trigger
+LANGUAGE plpgsql AS $$
+DECLARE
+ obj record;
+BEGIN
+ FOR obj IN SELECT * FROM pg_event_trigger_dropped_objects()
+ LOOP
+ IF obj.object_type = 'table' THEN
+ EXECUTE format('DROP TABLE IF EXISTS audit_tbls.%s',
+ obj.object_name);
+ END IF;
+
+ INSERT INTO dropped_objects
+ (type, schema, object, subobject, curr_user, sess_user) VALUES
+ (obj.object_type, obj.schema_name, obj.object_name,
+ obj.subobject_name, current_user, session_user);
+ END LOOP;
+END
+$$;
+
+CREATE EVENT TRIGGER regress_event_trigger_drop_objects ON ddl_command_end
+ WHEN TAG IN ('drop table', 'drop function', 'drop view',
+ 'drop owned', 'drop schema', 'alter table')
+ EXECUTE PROCEDURE test_evtrig_dropped_objects();
+
+ALTER TABLE schema_one.table_one DROP COLUMN a;
+DROP SCHEMA schema_one, schema_two CASCADE;
+
+SELECT * FROM dropped_objects WHERE schema IS NULL OR schema <> 'pg_toast';
+
+drop owned by regression_bob;
+SELECT * FROM dropped_objects WHERE type = 'schema';
+
drop role regression_bob;
+
+DROP EVENT TRIGGER regress_event_trigger_drop_objects;
--
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