DBZ-8403 Fix PostgreSQL 17 compilation

When compiling against PG17 on Debian testing with gcc 14, building
fails because of incompatible-pointer-type error. This commit updates
the macros added in e1f8714 to handle the pointer types.

Makefile

@@ -4,13 +4,8 @@ EXTENSION = decoderbufs
 PROTOBUF_C_CFLAGS = $(shell pkg-config --cflags 'libprotobuf-c >= 1.0.0')
 PROTOBUF_C_LDFLAGS = $(shell pkg-config --libs 'libprotobuf-c >= 1.0.0')
 
-ifneq ($(USE_POSTGIS),false)
-C_PARAMS = -DUSE_POSTGIS
-POSTGIS_C_LDFLAGS = -L/usr/local/lib -llwgeom
-endif
-
 PG_CPPFLAGS += -std=c11 $(PROTOBUF_C_CFLAGS) -I/usr/local/include $(C_PARAMS)
-SHLIB_LINK  += $(PROTOBUF_C_LDFLAGS) $(POSTGIS_C_LDFLAGS)
+SHLIB_LINK  += $(PROTOBUF_C_LDFLAGS)
 
 OBJS = src/decoderbufs.o src/proto/pg_logicaldec.pb-c.o
 

README.md

@@ -10,82 +10,130 @@
 A PostgreSQL logical decoder output plugin to deliver data as [Protocol Buffers](https://developers.google.com/protocol-buffers), adapted for Debezium
 
 ## Thanks to
-- The original [Decoderbufs Project](https://github.com/xstevens/decoderbufs) on which this is based 
+
+- The original [Decoderbufs Project](https://github.com/xstevens/decoderbufs) on which this is based
 - [The PostgreSQL Team](https://postgresql.org) for adding [logical decoding](http://www.postgresql.org/docs/9.4/static/logicaldecoding.html) support
 
 ## Dependencies
+
 This code depends on the following libraries and requires them for compilation:
 
-* [PostgreSQL](http://www.postgresql.org) 9.6+
-* [Protobuf-c](https://github.com/protobuf-c/protobuf-c) 1.2+ - used for data serialization
-* [PostGIS](http://www.postgis.net/) 2.1+ - used for Postgres geometric types support
+- [PostgreSQL](http://www.postgresql.org) 9.6+
+- [Protobuf-c](https://github.com/protobuf-c/protobuf-c) 1.2+ - used for data serialization
+- [PostGIS](http://www.postgis.net/) 2.1+ - used for Postgres geometric types support
 
 ## Building
 
-To build you will need to install PostgreSQL (for pg_config), PostgreSQL server development packages, protobuf-c for the
-Protocol Buffer support and some PostGIS development packages 
+`postgres-decoderbufs` has to be built from source after installing required dependencies.  The required dependencies are first PostgreSQL
+(for pg_config), PostgreSQL server development packages, protobuf-c for the Protocol Buffer support and some PostGIS development packages.
 
-### Debian
+### Installing Dependencies
 
-    # Core build utilities 
-    apt-get update && apt-get install -f -y software-properties-common build-essential pkg-config git postgresql-server-dev-9.6 
-    
-    # PostGIS dependency
-    apt-get install -f -y libproj-dev liblwgeom-dev
+#### Debian
 
-    # Protobuf-c dependency (requires a non-stable Debian repo)
-    add-apt-repository "deb http://ftp.debian.org/debian testing main contrib" && apt-get update
-    apt-get install -y libprotobuf-c-dev=1.2.1-1+b1
+```bash
+# Core build utilities 
+apt-get update && apt-get install -f -y software-properties-common build-essential pkg-config git postgresql-server-dev-9.6 
 
-The above are taken from the Debezium [docker images](https://github.com/debezium/docker-images).
+# PostGIS dependency
+apt-get install -f -y libproj-dev liblwgeom-dev
 
-### Other Linux distributions
+# Protobuf-c dependency (requires a non-stable Debian repo)
+add-apt-repository "deb http://ftp.debian.org/debian testing main contrib" && apt-get update
+apt-get install -y libprotobuf-c-dev=1.2.1-1+b1
+```
 
-You just need to make sure the above software packages (_or some flavour thereof_) are installed for your distro. 
+When updating the ProtoBuf definition, also install the ProtoBuf C compiler:
+
+```bash
+apt-get install -y protobuf-c-compiler=1.2.*
+```
+
+The above are taken from the Debezium [container images](https://github.com/debezium/docker-images).
+
+#### Other Linux distributions
+
+You just need to make sure the above software packages (_or some flavour thereof_) are installed for your distro.
 Note that the last step from the above sequence is only required for Debian to be able to install `libprotobuf-c-dev:1.2.1`
 
-If you have all of the prerequisites installed you should be able to just:
+### Getting the source code
 
-    make && make install
+If you have all of the above prerequisites installed, clone this git repo to build from source:
+
+```bash
+git clone https://github.com/debezium/postgres-decoderbufs.git
+cd postgres-decoderbufs
+```
+
+### Optional: Re-generating ProtoBuf code
+
+This is only needed after changes to the ProtoBuf definition (_proto/pg_logicaldec.proto):
+
+```bash
+cd proto
+protoc-c --c_out=../src/proto pg_logicaldec.proto
+cd ..
+```
+
+Commit the generated files to git then.
+
+### Building and installing decoderbufs
+
+If you have multiple Postgres versions installed, you can select which version to install decoderbufs into by altering your `$PATH` to point to the right version.
+Then `make` and `make install` for each version.  Here is an example:
+
+```bash
+# Install for Postgres 9.6 if I have multiple local versions
+export PATH=/usr/lib/postgresql/9.6/bin:$PATH
+make
+make install
+```
 
 Once the extension has been installed you just need to enable it and logical replication in postgresql.conf:
 
-    # MODULES
-    shared_preload_libraries = 'decoderbufs'
-    
-    # REPLICATION
-    wal_level = logical             # minimal, archive, hot_standby, or logical (change requires restart)
-    max_wal_senders = 8             # max number of walsender processes (change requires restart)
-    wal_keep_segments = 4           # in logfile segments, 16MB each; 0 disables
-    #wal_sender_timeout = 60s       # in milliseconds; 0 disables
-    max_replication_slots = 4       # max number of replication slots (change requires restart)
+```bash
+# MODULES
+shared_preload_libraries = 'decoderbufs'
+
+# REPLICATION
+wal_level = logical             # minimal, archive, hot_standby, or logical (change requires restart)
+max_wal_senders = 8             # max number of walsender processes (change requires restart)
+wal_keep_segments = 4           # in logfile segments, 16MB each; 0 disables
+#wal_sender_timeout = 60s       # in milliseconds; 0 disables
+max_replication_slots = 4       # max number of replication slots (change requires restart)
+```
 
 In addition, permissions will have to be added for the user that connects to the DB to be able to replicate. This can be modified in _pg\_hba.conf_ like so:
 
-    local   replication     <youruser>                          trust
-    host    replication     <youruser>  127.0.0.1/32            trust
-    host    replication     <youruser>  ::1/128                 trust
-    
+```make
+local   replication     <youruser>                          trust
+host    replication     <youruser>  127.0.0.1/32            trust
+host    replication     <youruser>  ::1/128                 trust
+```
+
 And restart PostgreSQL.
 
 ## Usage
-    -- can use SQL for demo purposes
-    select * from pg_create_logical_replication_slot('decoderbufs_demo', 'decoderbufs');
-    
-    -- DO SOME TABLE MODIFICATIONS (see below about UPDATE/DELETE)
-    
-    -- peek at WAL changes using decoderbufs debug mode for SQL console
-    select data from pg_logical_slot_peek_changes('decoderbufs_demo', NULL, NULL, 'debug-mode', '1');
-    -- get WAL changes using decoderbufs to update the WAL position
-    select data from pg_logical_slot_get_changes('decoderbufs_demo', NULL, NULL, 'debug-mode', '1');
-    
-    -- check the WAL position of logical replicators
-    select * from pg_replication_slots where slot_type = 'logical';
+
+```sql
+-- can use SQL for demo purposes
+select * from pg_create_logical_replication_slot('decoderbufs_demo', 'decoderbufs');
+
+-- DO SOME TABLE MODIFICATIONS (see below about UPDATE/DELETE)
+
+-- peek at WAL changes using decoderbufs debug mode for SQL console
+select data from pg_logical_slot_peek_changes('decoderbufs_demo', NULL, NULL, 'debug-mode', '1');
+-- get WAL changes using decoderbufs to update the WAL position
+select data from pg_logical_slot_get_changes('decoderbufs_demo', NULL, NULL, 'debug-mode', '1');
+
+-- check the WAL position of logical replicators
+select * from pg_replication_slots where slot_type = 'logical';
+```
 
 If you're performing an UPDATE/DELETE on your table and you don't see results for those operations from logical decoding, make sure you have set [REPLICA IDENTITY](http://www.postgresql.org/docs/9.4/static/sql-altertable.html#SQL-CREATETABLE-REPLICA-IDENTITY) appropriately for your use case.
-    
+
 The binary format will be consumed by the Debezium Postgres Connector.
-          
+
 ## Type Mappings
 
 The following table shows how current PostgreSQL type OIDs are mapped to which decoderbuf fields:
@@ -116,5 +164,5 @@ The following table shows how current PostgreSQL type OIDs are mapped to which d
 
 ## Support
 
-File bug reports and feature requests using [Debezium's JIRA](https://issues.jboss.org/browse/DBZ) and the 
+File bug reports and feature requests using [Debezium's JIRA](https://issues.jboss.org/browse/DBZ) and the
 [postgresql-connector](https://issues.jboss.org/browse/DBZ/component/12323543) component

proto/pg_logicaldec.proto

@@ -5,9 +5,12 @@ option java_outer_classname = "PgProto";
 option optimize_for = SPEED;
 
 enum Op {
+    UNKNOWN = -1;
     INSERT = 0;
     UPDATE = 1;
     DELETE = 2;
+    BEGIN  = 3;
+    COMMIT = 4;
 }
 
 message Point {
@@ -27,6 +30,7 @@ message DatumMessage {
       string datum_string = 8;
       bytes datum_bytes = 9;
       Point datum_point = 10;
+      bool datum_missing = 11;
     }
 }
 

rpms/postgres-decoderbufs.spec

@@ -0,0 +1,48 @@
+Name:		postgres-decoderbufs
+Version:	0.10.0
+Release:	1%{?dist}
+Summary:	PostgreSQL Protocol Buffers logical decoder plugin
+
+License:	MIT
+URL:		https://github.com/debezium/postgres-decoderbufs
+
+%global full_version %{version}.Final
+
+Source0:	https://github.com/debezium/%{name}/archive/v%{full_version}.tar.gz
+
+BuildRequires:	gcc
+BuildRequires:	postgresql-devel >= 9.6, postgresql-server-devel >= 9.6
+BuildRequires:	postgis-devel >= 2
+BuildRequires:	protobuf-c-devel
+
+Requires:	protobuf-c
+%{?postgresql_module_requires}
+
+Recommends:	postgis
+
+%description
+A PostgreSQL logical decoder output plugin to deliver data as Protocol Buffers messages.
+
+%prep
+%setup -qn postgres-decoderbufs-%{full_version}
+
+
+%build
+%make_build
+
+
+%install
+%make_install
+
+
+%files
+%doc README.md
+%license LICENSE
+%{_libdir}/pgsql/decoderbufs.so
+%{_datadir}/pgsql/extension/decoderbufs.control
+
+
+%changelog
+* Wed Oct 9 2019 - Jiri Pechanec <jpechane@redhat.com> 0.10.0-1
+* Tue May 14 2019 - Jiri Pechanec <jpechane@redhat.com> 0.9.5-1
+- Initial RPM packaging

src/decoderbufs.c

@@ -60,10 +60,10 @@
 #error Expecting timestamps to be represented as integers, not as floating-point.
 #endif
 
-#ifdef USE_POSTGIS
-/* POSTGIS version define so it doesn't redef macros */
-#define POSTGIS_PGSQL_VERSION 94
-#include "liblwgeom.h"
+#if PG_VERSION_NUM >= 170000
+#define TUPLE_ACCESS(x) x
+#else
+#define TUPLE_ACCESS(x) &x->tuple
 #endif
 
 PG_MODULE_MAGIC;
@@ -80,10 +80,6 @@ typedef struct {
   bool debug_mode;
 } DecoderData;
 
-/* GLOBALs for PostGIS dynamic OIDs */
-Oid geometry_oid = InvalidOid;
-Oid geography_oid = InvalidOid;
-
 /* these must be available to pg_dlsym() */
 extern void _PG_init(void);
 extern void _PG_output_plugin_init(OutputPluginCallbacks *cb);
@@ -119,9 +115,14 @@ static void pg_decode_startup(LogicalDecodingContext *ctx,
   elog(DEBUG1, "Entering startup callback");
 
   data = palloc(sizeof(DecoderData));
+#if PG_VERSION_NUM >= 90600
+  data->context = AllocSetContextCreate(
+      ctx->context, "decoderbufs context", ALLOCSET_DEFAULT_SIZES);
+#else
   data->context = AllocSetContextCreate(
       ctx->context, "decoderbufs context", ALLOCSET_DEFAULT_MINSIZE,
       ALLOCSET_DEFAULT_INITSIZE, ALLOCSET_DEFAULT_MAXSIZE);
+#endif
   data->debug_mode = false;
   opt->output_type = OUTPUT_PLUGIN_BINARY_OUTPUT;
 
@@ -169,32 +170,6 @@ static void pg_decode_shutdown(LogicalDecodingContext *ctx) {
   MemoryContextDelete(data->context);
 }
 
-/* BEGIN callback */
-static void pg_decode_begin_txn(LogicalDecodingContext *ctx,
-                                ReorderBufferTXN *txn) {
-#ifdef USE_POSTGIS
-  // set PostGIS geometry type id (these are dynamic)
-  // TODO: Figure out how to make sure we get the typid's from postgis extension namespace
-  if (geometry_oid == InvalidOid) {
-    geometry_oid = TypenameGetTypid("geometry");
-    if (geometry_oid != InvalidOid) {
-      elog(DEBUG1, "PostGIS geometry type detected: %u", geometry_oid);
-    }
-  }
-  if (geography_oid == InvalidOid) {
-    geography_oid = TypenameGetTypid("geography");
-    if (geography_oid != InvalidOid) {
-      elog(DEBUG1, "PostGIS geometry type detected: %u", geography_oid);
-    }
-  }
-#endif
-}
-
-/* COMMIT callback */
-static void pg_decode_commit_txn(LogicalDecodingContext *ctx,
-                                 ReorderBufferTXN *txn, XLogRecPtr commit_lsn) {
-}
-
 /* print tuple datums (only used for debug-mode) */
 static void print_tuple_datums(StringInfo out, Decoderbufs__DatumMessage **tup,
                                size_t n) {
@@ -275,76 +250,16 @@ static void print_row_msg(StringInfo out, Decoderbufs__RowMessage *rmsg) {
 
 }
 
-/* this doesn't seem to be available in the public api (unfortunate) */
-static double numeric_to_double_no_overflow(Numeric num) {
-  char *tmp;
-  double val;
-  char *endptr;
-
-  tmp = DatumGetCString(DirectFunctionCall1(numeric_out, NumericGetDatum(num)));
-
-  /* unlike float8in, we ignore ERANGE from strtod */
-  val = strtod(tmp, &endptr);
-  if (*endptr != '\0') {
-    /* shouldn't happen ... */
-    ereport(ERROR,
-            (errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
-             errmsg("invalid input syntax for type double precision: \"%s\"",
-                    tmp)));
-  }
-
-  return val;
-}
-
-static bool geography_point_as_decoderbufs_point(Datum datum,
-                                                 Decoderbufs__Point *p) {
-#ifdef USE_POSTGIS
-  GSERIALIZED *geom;
-  LWGEOM *lwgeom;
-  LWPOINT *point = NULL;
-  POINT2D p2d;
-
-  geom = (GSERIALIZED *)PG_DETOAST_DATUM(datum);
-  if (gserialized_get_type(geom) != POINTTYPE) {
-    return false;
-  }
-
-  lwgeom = lwgeom_from_gserialized(geom);
-  point = lwgeom_as_lwpoint(lwgeom);
-  if (lwgeom_is_empty(lwgeom)) {
-    return false;
-  }
-
-  getPoint2d_p(point->point, 0, &p2d);
-
-  if (p != NULL) {
-    Decoderbufs__Point dp = DECODERBUFS__POINT__INIT;
-    dp.x = p2d.x;
-    dp.y = p2d.y;
-    memcpy(p, &dp, sizeof(dp));
-    elog(DEBUG1, "Translating geography to point: (x,y) = (%f,%f)", p->x, p->y);
-  }
-
-  return true;
-#else
-  elog(DEBUG1, "PostGIS support is off, recompile decoderbufs with USE_POSTGIS option!");
-  return false;
-#endif
-}
-
 /* set a datum value based on its OID specified by typid */
 static void set_datum_value(Decoderbufs__DatumMessage *datum_msg, Oid typid,
                             Oid typoutput, Datum datum) {
-  Numeric num;
   bytea *valptr = NULL;
   const char *output = NULL;
   Point *p = NULL;
   Timestamp ts;
-  double duration;
   TimeTzADT *timetz = NULL;
-  Interval   *interval = NULL;
   Decoderbufs__Point dp = DECODERBUFS__POINT__INIT;
-     
+
   int size = 0;
   switch (typid) {
     case BOOLOID:
@@ -360,10 +275,13 @@ static void set_datum_value(Decoderbufs__DatumMessage *datum_msg, Oid typid,
       datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_INT32;
       break;
     case INT8OID:
-    case OIDOID:
       datum_msg->datum_int64 = DatumGetInt64(datum);
       datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_INT64;
       break;
+    case OIDOID:
+      datum_msg->datum_int64 = (Oid) DatumGetUInt64(datum);
+      datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_INT64;
+      break;
     case FLOAT4OID:
       datum_msg->datum_float = DatumGetFloat4(datum);
       datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_FLOAT;
@@ -372,7 +290,7 @@ static void set_datum_value(Decoderbufs__DatumMessage *datum_msg, Oid typid,
       datum_msg->datum_double = DatumGetFloat8(datum);
       datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_DOUBLE;
       break;
-    case CASHOID: 
+    case CASHOID:
       datum_msg->datum_int64 = DatumGetCash(datum);
       datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_INT64;
       break;
@@ -382,11 +300,12 @@ static void set_datum_value(Decoderbufs__DatumMessage *datum_msg, Oid typid,
     case BPCHAROID:
     case TEXTOID:
     case JSONOID:
-    case JSONBOID: 
+    case JSONBOID:
     case XMLOID:
     case BITOID:
     case VARBITOID:
     case UUIDOID:
+    case INTERVALOID:
       output = OidOutputFunctionCall(typoutput, datum);
       datum_msg->datum_string = pnstrdup(output, strlen(output));
       datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_STRING;
@@ -394,24 +313,22 @@ static void set_datum_value(Decoderbufs__DatumMessage *datum_msg, Oid typid,
     case TIMESTAMPOID:
       ts = DatumGetTimestamp(datum);
       if (TIMESTAMP_NOT_FINITE(ts)) {
-           ereport(ERROR, (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
-           errmsg("timestamp \'%s\'out of range", ts ? strVal(ts) : "(null)")));
+           datum_msg->datum_int64 = ts;
       } else {
            datum_msg->datum_int64 = TIMESTAMPTZ_TO_USEC_SINCE_EPOCH(ts);
-           datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_INT64;
-           break;       
       }
+      datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_INT64;
+      break;
     case TIMESTAMPTZOID:
       ts = DatumGetTimestampTz(datum);
       if (TIMESTAMP_NOT_FINITE(ts)) {
-           ereport(ERROR, (errcode(ERRCODE_DATETIME_VALUE_OUT_OF_RANGE),
-           errmsg("timestamp \'%s\'out of range", ts ? strVal(ts) : "(null)")));
-       } else {
+           datum_msg->datum_int64 = ts;
+      } else {
            datum_msg->datum_int64 = TIMESTAMPTZ_TO_USEC_SINCE_EPOCH(ts);
-           datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_INT64;
-           break;       
-        }
-    case DATEOID: 
+      }
+      datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_INT64;
+      break;
+    case DATEOID:
       /* simply get the number of days as the stored 32 bit value and convert to EPOCH */
       datum_msg->datum_int32 = DATE_TO_DAYS_SINCE_EPOCH(DatumGetDateADT(datum));
       datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_INT32;
@@ -419,21 +336,12 @@ static void set_datum_value(Decoderbufs__DatumMessage *datum_msg, Oid typid,
     case TIMEOID:
       datum_msg->datum_int64 = DatumGetTimeADT(datum);
       datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_INT64;
-      break;                                                 
+      break;
     case TIMETZOID:
       timetz = DatumGetTimeTzADTP(datum);
-      /* use GMT-equivalent time */     
+      /* use GMT-equivalent time */
       datum_msg->datum_double = (double) (timetz->time + (timetz->zone * 1000000.0));
       datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_DOUBLE;
-      break;     
-    case INTERVALOID:
-      interval = DatumGetIntervalP(datum);
-      /* 
-        Convert the month part of Interval to days using assumed average month length of 365.25/12.0 days. 
-      */  
-      duration = interval->time + interval->day * (double) USECS_PER_DAY + interval->month * ((DAYS_PER_YEAR / (double) MONTHS_PER_YEAR) * USECS_PER_DAY);
-      datum_msg->datum_double = duration;
-      datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_DOUBLE;
       break;
     case BYTEAOID:
       valptr = DatumGetByteaPCopy(datum);
@@ -452,13 +360,7 @@ static void set_datum_value(Decoderbufs__DatumMessage *datum_msg, Oid typid,
       datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_POINT;
       break;
     default:
-      // PostGIS uses dynamic OIDs so we need to check the type again here
-      if (typid == geometry_oid || typid == geography_oid) {
-        elog(DEBUG1, "Converting geography point to datum_point");
-        datum_msg->datum_point = palloc(sizeof(Decoderbufs__Point));
-        geography_point_as_decoderbufs_point(datum, datum_msg->datum_point);
-        datum_msg->datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_POINT;
-      } else {
+      {
         int len;
         elog(DEBUG1, "Encountered unknown typid: %d, using bytes", typid);
         output = OidOutputFunctionCall(typoutput, datum);
@@ -478,15 +380,15 @@ static int valid_attributes_count_from(TupleDesc tupdesc) {
   int natt;
   int count = 0;
   for (natt = 0; natt < tupdesc->natts; natt++) {
-      Form_pg_attribute attr = tupdesc->attrs[natt];
-      
+      Form_pg_attribute attr = TupleDescAttr(tupdesc, natt);
+
       /* skip dropped columns and system columns */
-      if (attr->attisdropped  || attr->attnum < 0) {       
+      if (attr->attisdropped  || attr->attnum < 0) {
         continue;
-      }    
-      count++;      
+      }
+      count++;
   }
-  return count;    
+  return count;
 }
 
 /* convert a PG tuple to an array of DatumMessage(s) */
@@ -506,20 +408,20 @@ static void tuple_to_tuple_msg(Decoderbufs__DatumMessage **tmsg,
     bool typisvarlena;
     Decoderbufs__DatumMessage datum_msg = DECODERBUFS__DATUM_MESSAGE__INIT;
 
-    attr = tupdesc->attrs[natt];
-    
+    attr = TupleDescAttr(tupdesc, natt);
+
     /* skip dropped columns and system columns */
     if (attr->attisdropped || attr->attnum < 0) {
       elog(DEBUG1, "skipping column %d because %s", natt + 1, attr->attisdropped ? "it's a dropped column" : "it's a system column");
       continue;
-    }    
+    }
 
-    attrName = quote_identifier(NameStr(attr->attname));     
-    elog(DEBUG1, "processing column %d with name %s", natt + 1, attrName);    
+    attrName = quote_identifier(NameStr(attr->attname));
+    elog(DEBUG1, "processing column %d with name %s", natt + 1, attrName);
 
     /* set the column name */
     datum_msg.column_name = (char *)attrName;
-    
+
     /* set datum from tuple */
     origval = heap_getattr(tuple, natt + 1, tupdesc, &isnull);
 
@@ -531,7 +433,8 @@ static void tuple_to_tuple_msg(Decoderbufs__DatumMessage **tmsg,
     getTypeOutputInfo(attr->atttypid, &typoutput, &typisvarlena);
     if (!isnull) {
       if (typisvarlena && VARATT_IS_EXTERNAL_ONDISK(origval)) {
-        // TODO: Is there a way we can handle this?
+        datum_msg.datum_missing = true;
+        datum_msg.datum_case = DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_MISSING;
         elog(DEBUG1, "Not handling external on disk varlena at the moment.");
       } else if (!typisvarlena) {
         set_datum_value(&datum_msg, attr->atttypid, typoutput, origval);
@@ -540,7 +443,7 @@ static void tuple_to_tuple_msg(Decoderbufs__DatumMessage **tmsg,
         set_datum_value(&datum_msg, attr->atttypid, typoutput, val);
       }
     } else {
-      elog(DEBUG1, "column %s is null, ignoring value", attrName);  
+      elog(DEBUG1, "column %s is null, ignoring value", attrName);
     }
 
     tmsg[valid_attr_cnt] = palloc(sizeof(datum_msg));
@@ -564,7 +467,7 @@ static void add_metadata_to_msg(Decoderbufs__TypeInfo **tmsg,
     Decoderbufs__TypeInfo typeinfo = DECODERBUFS__TYPE_INFO__INIT;
     bool not_null;
 
-    attr = tupdesc->attrs[natt];
+    attr = TupleDescAttr(tupdesc, natt);
 
     /* skip dropped columns and system columns */
     if (attr->attisdropped || attr->attnum < 0) {
@@ -585,6 +488,90 @@ static void add_metadata_to_msg(Decoderbufs__TypeInfo **tmsg,
   }
 }
 
+/* BEGIN callback */
+static void pg_decode_begin_txn(LogicalDecodingContext *ctx,
+                                ReorderBufferTXN *txn) {
+
+  DecoderData *data;
+  MemoryContext old;
+  Decoderbufs__RowMessage rmsg = DECODERBUFS__ROW_MESSAGE__INIT;
+  elog(DEBUG1, "Entering begin callback");
+
+
+  /* Avoid leaking memory by using and resetting our own context */
+  data = ctx->output_plugin_private;
+  old = MemoryContextSwitchTo(data->context);
+
+  rmsg.op = DECODERBUFS__OP__BEGIN;
+  rmsg.has_op = true;
+  rmsg.transaction_id = txn->xid;
+  rmsg.has_transaction_id = true;
+#if PG_VERSION_NUM >= 150000
+  rmsg.commit_time = TIMESTAMPTZ_TO_USEC_SINCE_EPOCH(txn->xact_time.commit_time);
+#else
+  rmsg.commit_time = TIMESTAMPTZ_TO_USEC_SINCE_EPOCH(txn->commit_time);
+#endif
+  rmsg.has_commit_time = true;
+
+  /* write msg */
+  OutputPluginPrepareWrite(ctx, true);
+  if (data->debug_mode) {
+    print_row_msg(ctx->out, &rmsg);
+  } else {
+    size_t psize = decoderbufs__row_message__get_packed_size(&rmsg);
+    void *packed = palloc(psize);
+    size_t ssize = decoderbufs__row_message__pack(&rmsg, packed);
+    appendBinaryStringInfo(ctx->out, packed, ssize);
+  }
+  OutputPluginWrite(ctx, true);
+
+  /* Cleanup, freeing memory */
+  MemoryContextSwitchTo(old);
+  MemoryContextReset(data->context);
+}
+
+/* COMMIT callback */
+static void pg_decode_commit_txn(LogicalDecodingContext *ctx,
+                                 ReorderBufferTXN *txn, XLogRecPtr commit_lsn) {
+
+  DecoderData *data;
+  MemoryContext old;
+  Decoderbufs__RowMessage rmsg = DECODERBUFS__ROW_MESSAGE__INIT;
+  elog(DEBUG1, "Entering commit callback");
+
+
+  /* Avoid leaking memory by using and resetting our own context */
+  data = ctx->output_plugin_private;
+  old = MemoryContextSwitchTo(data->context);
+
+  rmsg.op = DECODERBUFS__OP__COMMIT;
+  rmsg.has_op = true;
+  rmsg.transaction_id = txn->xid;
+  rmsg.has_transaction_id = true;
+#if PG_VERSION_NUM >= 150000
+  rmsg.commit_time = TIMESTAMPTZ_TO_USEC_SINCE_EPOCH(txn->xact_time.commit_time);
+#else
+  rmsg.commit_time = TIMESTAMPTZ_TO_USEC_SINCE_EPOCH(txn->commit_time);
+#endif
+  rmsg.has_commit_time = true;
+
+  /* write msg */
+  OutputPluginPrepareWrite(ctx, true);
+  if (data->debug_mode) {
+    print_row_msg(ctx->out, &rmsg);
+  } else {
+    size_t psize = decoderbufs__row_message__get_packed_size(&rmsg);
+    void *packed = palloc(psize);
+    size_t ssize = decoderbufs__row_message__pack(&rmsg, packed);
+    appendBinaryStringInfo(ctx->out, packed, ssize);
+  }
+  OutputPluginWrite(ctx, true);
+
+  /* Cleanup, freeing memory */
+  MemoryContextSwitchTo(old);
+  MemoryContextReset(data->context);
+}
+
 /* callback for individual changed tuples */
 static void pg_decode_change(LogicalDecodingContext *ctx, ReorderBufferTXN *txn,
                              Relation relation, ReorderBufferChange *change) {
@@ -617,12 +604,16 @@ static void pg_decode_change(LogicalDecodingContext *ctx, ReorderBufferTXN *txn,
   /* set common fields */
   rmsg.transaction_id = txn->xid;
   rmsg.has_transaction_id = true;
+#if PG_VERSION_NUM >= 150000
+  rmsg.commit_time = TIMESTAMPTZ_TO_USEC_SINCE_EPOCH(txn->xact_time.commit_time);
+#else
   rmsg.commit_time = TIMESTAMPTZ_TO_USEC_SINCE_EPOCH(txn->commit_time);
+#endif
   rmsg.has_commit_time = true;
-  rmsg.table = pstrdup(quote_qualified_identifier(get_namespace_name(get_rel_namespace(RelationGetRelid(relation))), 
+  rmsg.table = pstrdup(quote_qualified_identifier(get_namespace_name(get_rel_namespace(RelationGetRelid(relation))),
     NameStr(class_form->relname)));
-  
- 
+
+
   /* decode different operation types */
   switch (change->action) {
     case REORDER_BUFFER_CHANGE_INSERT:
@@ -637,13 +628,13 @@ static void pg_decode_change(LogicalDecodingContext *ctx, ReorderBufferTXN *txn,
         rmsg.new_tuple =
             palloc(sizeof(Decoderbufs__DatumMessage*) * rmsg.n_new_tuple);
         tuple_to_tuple_msg(rmsg.new_tuple, relation,
-                           &change->data.tp.newtuple->tuple, tupdesc);
+                           TUPLE_ACCESS(change->data.tp.newtuple), tupdesc);
 
         rmsg.n_new_typeinfo = rmsg.n_new_tuple;
         rmsg.new_typeinfo =
             palloc(sizeof(Decoderbufs__TypeInfo*) * rmsg.n_new_typeinfo);
         add_metadata_to_msg(rmsg.new_typeinfo, relation,
-                           &change->data.tp.newtuple->tuple, tupdesc);
+                           TUPLE_ACCESS(change->data.tp.newtuple), tupdesc);
       }
       break;
     case REORDER_BUFFER_CHANGE_UPDATE:
@@ -658,7 +649,7 @@ static void pg_decode_change(LogicalDecodingContext *ctx, ReorderBufferTXN *txn,
           rmsg.old_tuple =
               palloc(sizeof(Decoderbufs__DatumMessage*) * rmsg.n_old_tuple);
           tuple_to_tuple_msg(rmsg.old_tuple, relation,
-                             &change->data.tp.oldtuple->tuple, tupdesc);
+                             TUPLE_ACCESS(change->data.tp.oldtuple), tupdesc);
         }
         if (change->data.tp.newtuple != NULL) {
           elog(DEBUG1, "decoding new tuple information");
@@ -668,13 +659,13 @@ static void pg_decode_change(LogicalDecodingContext *ctx, ReorderBufferTXN *txn,
           rmsg.new_tuple =
               palloc(sizeof(Decoderbufs__DatumMessage*) * rmsg.n_new_tuple);
           tuple_to_tuple_msg(rmsg.new_tuple, relation,
-                             &change->data.tp.newtuple->tuple, tupdesc);
+                             TUPLE_ACCESS(change->data.tp.newtuple), tupdesc);
 
           rmsg.n_new_typeinfo = rmsg.n_new_tuple;
           rmsg.new_typeinfo =
               palloc(sizeof(Decoderbufs__TypeInfo*) * rmsg.n_new_typeinfo);
           add_metadata_to_msg(rmsg.new_typeinfo, relation,
-                             &change->data.tp.newtuple->tuple, tupdesc);
+                             TUPLE_ACCESS(change->data.tp.newtuple), tupdesc);
         }
       }
       break;
@@ -690,13 +681,13 @@ static void pg_decode_change(LogicalDecodingContext *ctx, ReorderBufferTXN *txn,
         rmsg.old_tuple =
             palloc(sizeof(Decoderbufs__DatumMessage*) *  rmsg.n_old_tuple);
         tuple_to_tuple_msg(rmsg.old_tuple, relation,
-                           &change->data.tp.oldtuple->tuple, tupdesc);
+                           TUPLE_ACCESS(change->data.tp.oldtuple), tupdesc);
       } else {
         elog(DEBUG1, "no information to decode from DELETE because either no PK is present or REPLICA IDENTITY NOTHING or invalid ");
       }
       break;
     default:
-      elog(WARNING, "unknown change action");       
+      elog(WARNING, "unknown change action");
       Assert(0);
       break;
   }

src/proto/pg_logicaldec.pb-c.c

@@ -230,7 +230,7 @@ const ProtobufCMessageDescriptor decoderbufs__point__descriptor =
   (ProtobufCMessageInit) decoderbufs__point__init,
   NULL,NULL,NULL    /* reserved[123] */
 };
-static const ProtobufCFieldDescriptor decoderbufs__datum_message__field_descriptors[10] =
+static const ProtobufCFieldDescriptor decoderbufs__datum_message__field_descriptors[11] =
 {
   {
     "column_name",
@@ -352,6 +352,18 @@ static const ProtobufCFieldDescriptor decoderbufs__datum_message__field_descript
     0 | PROTOBUF_C_FIELD_FLAG_ONEOF,             /* flags */
     0,NULL,NULL    /* reserved1,reserved2, etc */
   },
+  {
+    "datum_missing",
+    11,
+    PROTOBUF_C_LABEL_OPTIONAL,
+    PROTOBUF_C_TYPE_BOOL,
+    offsetof(Decoderbufs__DatumMessage, datum_case),
+    offsetof(Decoderbufs__DatumMessage, datum_missing),
+    NULL,
+    NULL,
+    0 | PROTOBUF_C_FIELD_FLAG_ONEOF,             /* flags */
+    0,NULL,NULL    /* reserved1,reserved2, etc */
+  },
 };
 static const unsigned decoderbufs__datum_message__field_indices_by_name[] = {
   0,   /* field[0] = column_name */
@@ -362,13 +374,14 @@ static const unsigned decoderbufs__datum_message__field_indices_by_name[] = {
   4,   /* field[4] = datum_float */
   2,   /* field[2] = datum_int32 */
   3,   /* field[3] = datum_int64 */
+  10,   /* field[10] = datum_missing */
   9,   /* field[9] = datum_point */
   7,   /* field[7] = datum_string */
 };
 static const ProtobufCIntRange decoderbufs__datum_message__number_ranges[1 + 1] =
 {
   { 1, 0 },
-  { 0, 10 }
+  { 0, 11 }
 };
 const ProtobufCMessageDescriptor decoderbufs__datum_message__descriptor =
 {
@@ -378,7 +391,7 @@ const ProtobufCMessageDescriptor decoderbufs__datum_message__descriptor =
   "Decoderbufs__DatumMessage",
   "decoderbufs",
   sizeof(Decoderbufs__DatumMessage),
-  10,
+  11,
   decoderbufs__datum_message__field_descriptors,
   decoderbufs__datum_message__field_indices_by_name,
   1,  decoderbufs__datum_message__number_ranges,
@@ -552,20 +565,26 @@ const ProtobufCMessageDescriptor decoderbufs__row_message__descriptor =
   (ProtobufCMessageInit) decoderbufs__row_message__init,
   NULL,NULL,NULL    /* reserved[123] */
 };
-static const ProtobufCEnumValue decoderbufs__op__enum_values_by_number[3] =
+static const ProtobufCEnumValue decoderbufs__op__enum_values_by_number[6] =
 {
+  { "UNKNOWN", "DECODERBUFS__OP__UNKNOWN", -1 },
   { "INSERT", "DECODERBUFS__OP__INSERT", 0 },
   { "UPDATE", "DECODERBUFS__OP__UPDATE", 1 },
   { "DELETE", "DECODERBUFS__OP__DELETE", 2 },
+  { "BEGIN", "DECODERBUFS__OP__BEGIN", 3 },
+  { "COMMIT", "DECODERBUFS__OP__COMMIT", 4 },
 };
 static const ProtobufCIntRange decoderbufs__op__value_ranges[] = {
-{0, 0},{0, 3}
+{-1, 0},{0, 6}
 };
-static const ProtobufCEnumValueIndex decoderbufs__op__enum_values_by_name[3] =
+static const ProtobufCEnumValueIndex decoderbufs__op__enum_values_by_name[6] =
 {
-  { "DELETE", 2 },
-  { "INSERT", 0 },
-  { "UPDATE", 1 },
+  { "BEGIN", 4 },
+  { "COMMIT", 5 },
+  { "DELETE", 3 },
+  { "INSERT", 1 },
+  { "UNKNOWN", 0 },
+  { "UPDATE", 2 },
 };
 const ProtobufCEnumDescriptor decoderbufs__op__descriptor =
 {
@@ -574,9 +593,9 @@ const ProtobufCEnumDescriptor decoderbufs__op__descriptor =
   "Op",
   "Decoderbufs__Op",
   "decoderbufs",
-  3,
+  6,
   decoderbufs__op__enum_values_by_number,
-  3,
+  6,
   decoderbufs__op__enum_values_by_name,
   1,
   decoderbufs__op__value_ranges,

src/proto/pg_logicaldec.pb-c.h

@@ -24,9 +24,12 @@ typedef struct _Decoderbufs__RowMessage Decoderbufs__RowMessage;
 /* --- enums --- */
 
 typedef enum _Decoderbufs__Op {
+  DECODERBUFS__OP__UNKNOWN = -1,
   DECODERBUFS__OP__INSERT = 0,
   DECODERBUFS__OP__UPDATE = 1,
-  DECODERBUFS__OP__DELETE = 2
+  DECODERBUFS__OP__DELETE = 2,
+  DECODERBUFS__OP__BEGIN = 3,
+  DECODERBUFS__OP__COMMIT = 4
     PROTOBUF_C__FORCE_ENUM_TO_BE_INT_SIZE(DECODERBUFS__OP)
 } Decoderbufs__Op;
 
@@ -53,6 +56,7 @@ typedef enum {
   DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_STRING = 8,
   DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_BYTES = 9,
   DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_POINT = 10,
+  DECODERBUFS__DATUM_MESSAGE__DATUM_DATUM_MISSING = 11,
 } Decoderbufs__DatumMessage__DatumCase;
 
 struct  _Decoderbufs__DatumMessage
@@ -71,6 +75,7 @@ struct  _Decoderbufs__DatumMessage
     char *datum_string;
     ProtobufCBinaryData datum_bytes;
     Decoderbufs__Point *datum_point;
+    protobuf_c_boolean datum_missing;
   };
 };
 #define DECODERBUFS__DATUM_MESSAGE__INIT \