mirror/postgresql
2
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2025-01-12 15:39:35 +08:00
Code Issues Packages Projects Releases Wiki Activity

Fix/improve bytea and boolean support in PL/Python

Browse Source 
Before, PL/Python converted data between SQL and Python by going
through a C string representation.  This broke for bytea in two ways:

- On input (function parameters), you would get a Python string that
  contains bytea's particular external representation with backslashes
  etc., instead of a sequence of bytes, which is what you would expect
  in a Python environment.  This problem is exacerbated by the new
  bytea output format.

- On output (function return value), null bytes in the Python string
  would cause truncation before the data gets stored into a bytea
  datum.

This is now fixed by converting directly between the PostgreSQL datum
and the Python representation.

The required generalized infrastructure also allows for other
improvements in passing:

- When returning a boolean value, the SQL datum is now true if and
  only if Python considers the value that was passed out of the
  PL/Python function to be true.  Previously, this determination was
  left to the boolean data type input function.  So, now returning
  'foo' results in true, because Python considers it true, rather than
  false because PostgreSQL considers it false.

- On input, we can convert the integer and float types directly to
  their Python equivalents without having to go through an
  intermediate string representation.

original patch by Caleb Welton, with updates by myself
This commit is contained in:
Peter Eisentraut 2009-09-09 19:00:09 +00:00
parent 255f66efa9
commit 3ab8b7fa6f
5 changed files with 456 additions and 147 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

39
src/backend/utils/adt/domains.c
View File

@ -25,7 +25,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/utils/adt/domains.c,v 1.8 2009/01/01 17:23:49 momjian Exp $
* $PostgreSQL: pgsql/src/backend/utils/adt/domains.c,v 1.9 2009/09/09 19:00:09 petere Exp $
*
*-------------------------------------------------------------------------
*/
@ -302,3 +302,40 @@ domain_recv(PG_FUNCTION_ARGS)
else
PG_RETURN_DATUM(value);
}
/*
* domain_check - check that a datum satisfies the constraints of a
* domain. extra and mcxt can be passed if they are available from,
* say, a FmgrInfo structure, or they can be NULL, in which case the
* setup is repeated for each call.
*/
void
domain_check(Datum value, bool isnull, Oid domainType, void **extra, MemoryContext mcxt)
{
DomainIOData *my_extra = NULL;
if (mcxt == NULL)
mcxt = CurrentMemoryContext;
/*
* We arrange to look up the needed info just once per series of calls,
* assuming the domain type doesn't change underneath us.
*/
if (extra)
my_extra = (DomainIOData *) *extra;
if (my_extra == NULL)
{
my_extra = (DomainIOData *) MemoryContextAlloc(mcxt,
sizeof(DomainIOData));
domain_state_setup(my_extra, domainType, true, mcxt);
if (extra)
*extra = (void *) my_extra;
}
else if (my_extra->domain_type != domainType)
domain_state_setup(my_extra, domainType, true, mcxt);
/*
* Do the necessary checks to ensure it's a valid domain value.
*/
domain_check_input(value, isnull, my_extra);
}

3
src/include/utils/builtins.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/utils/builtins.h,v 1.338 2009/08/04 16:08:36 tgl Exp $
* $PostgreSQL: pgsql/src/include/utils/builtins.h,v 1.339 2009/09/09 19:00:09 petere Exp $
*
*-------------------------------------------------------------------------
*/
@ -137,6 +137,7 @@ extern Datum char_text(PG_FUNCTION_ARGS);
/* domains.c */
extern Datum domain_in(PG_FUNCTION_ARGS);
extern Datum domain_recv(PG_FUNCTION_ARGS);
extern void domain_check(Datum value, bool isnull, Oid domainType, void **extra, MemoryContext mcxt);
/* encode.c */
extern Datum binary_encode(PG_FUNCTION_ARGS);

124
src/pl/plpython/expected/plpython_types.out
View File

@ -32,6 +32,74 @@ CONTEXT: PL/Python function "test_type_conversion_bool"
(1 row)
-- test various other ways to express Booleans in Python
CREATE FUNCTION test_type_conversion_bool_other(n int) RETURNS bool AS $$
# numbers
if n == 0:
ret = 0
elif n == 1:
ret = 5
# strings
elif n == 2:
ret = ''
elif n == 3:
ret = 'fa' # true in Python, false in PostgreSQL
# containers
elif n == 4:
ret = []
elif n == 5:
ret = [0]
plpy.info(ret, not not ret)
return ret
$$ LANGUAGE plpythonu;
SELECT * FROM test_type_conversion_bool_other(0);
INFO: (0, False)
CONTEXT: PL/Python function "test_type_conversion_bool_other"
test_type_conversion_bool_other
---------------------------------
f
(1 row)
SELECT * FROM test_type_conversion_bool_other(1);
INFO: (5, True)
CONTEXT: PL/Python function "test_type_conversion_bool_other"
test_type_conversion_bool_other
---------------------------------
t
(1 row)
SELECT * FROM test_type_conversion_bool_other(2);
INFO: ('', False)
CONTEXT: PL/Python function "test_type_conversion_bool_other"
test_type_conversion_bool_other
---------------------------------
f
(1 row)
SELECT * FROM test_type_conversion_bool_other(3);
INFO: ('fa', True)
CONTEXT: PL/Python function "test_type_conversion_bool_other"
test_type_conversion_bool_other
---------------------------------
t
(1 row)
SELECT * FROM test_type_conversion_bool_other(4);
INFO: ([], False)
CONTEXT: PL/Python function "test_type_conversion_bool_other"
test_type_conversion_bool_other
---------------------------------
f
(1 row)
SELECT * FROM test_type_conversion_bool_other(5);
INFO: ([0], True)
CONTEXT: PL/Python function "test_type_conversion_bool_other"
test_type_conversion_bool_other
---------------------------------
t
(1 row)
CREATE FUNCTION test_type_conversion_char(x char) RETURNS char AS $$
plpy.info(x, type(x))
return x
@ -278,13 +346,21 @@ plpy.info(x, type(x))
return x
$$ LANGUAGE plpythonu;
SELECT * FROM test_type_conversion_bytea('hello world');
INFO: ('\\x68656c6c6f20776f726c64', <type 'str'>)
INFO: ('hello world', <type 'str'>)
CONTEXT: PL/Python function "test_type_conversion_bytea"
test_type_conversion_bytea
----------------------------
\x68656c6c6f20776f726c64
(1 row)
SELECT * FROM test_type_conversion_bytea(E'null\\000byte');
INFO: ('null\x00byte', <type 'str'>)
CONTEXT: PL/Python function "test_type_conversion_bytea"
test_type_conversion_bytea
----------------------------
\x6e756c6c0062797465
(1 row)
SELECT * FROM test_type_conversion_bytea(null);
INFO: (None, <type 'NoneType'>)
CONTEXT: PL/Python function "test_type_conversion_bytea"
@ -304,17 +380,31 @@ try:
except ValueError, e:
return 'FAILED: ' + str(e)
$$ LANGUAGE plpythonu;
/* This will currently fail because the bytea datum is presented to
Python as a string in bytea-encoding, which Python doesn't understand. */
SELECT test_type_unmarshal(x) FROM test_type_marshal() x;
test_type_unmarshal
--------------------------
FAILED: bad marshal data
test_type_unmarshal
---------------------
hello world
(1 row)
--
-- Domains
--
CREATE DOMAIN booltrue AS bool CHECK (VALUE IS TRUE OR VALUE IS NULL);
CREATE FUNCTION test_type_conversion_booltrue(x booltrue, y bool) RETURNS booltrue AS $$
return y
$$ LANGUAGE plpythonu;
SELECT * FROM test_type_conversion_booltrue(true, true);
test_type_conversion_booltrue
-------------------------------
t
(1 row)
SELECT * FROM test_type_conversion_booltrue(false, true);
ERROR: value for domain booltrue violates check constraint "booltrue_check"
SELECT * FROM test_type_conversion_booltrue(true, false);
ERROR: value for domain booltrue violates check constraint "booltrue_check"
CONTEXT: while creating return value
PL/Python function "test_type_conversion_booltrue"
CREATE DOMAIN uint2 AS int2 CHECK (VALUE >= 0);
CREATE FUNCTION test_type_conversion_uint2(x uint2, y int) RETURNS uint2 AS $$
plpy.info(x, type(x))
@ -342,13 +432,29 @@ CONTEXT: PL/Python function "test_type_conversion_uint2"
1
(1 row)
CREATE DOMAIN nnint AS int CHECK (VALUE IS NOT NULL);
CREATE FUNCTION test_type_conversion_nnint(x nnint, y int) RETURNS nnint AS $$
return y
$$ LANGUAGE plpythonu;
SELECT * FROM test_type_conversion_nnint(10, 20);
test_type_conversion_nnint
----------------------------
20
(1 row)
SELECT * FROM test_type_conversion_nnint(null, 20);
ERROR: value for domain nnint violates check constraint "nnint_check"
SELECT * FROM test_type_conversion_nnint(10, null);
ERROR: value for domain nnint violates check constraint "nnint_check"
CONTEXT: while creating return value
PL/Python function "test_type_conversion_nnint"
CREATE DOMAIN bytea10 AS bytea CHECK (octet_length(VALUE) = 10 AND VALUE IS NOT NULL);
CREATE FUNCTION test_type_conversion_bytea10(x bytea10, y bytea) RETURNS bytea10 AS $$
plpy.info(x, type(x))
return y
$$ LANGUAGE plpythonu;
SELECT * FROM test_type_conversion_bytea10('hello wold', 'hello wold');
INFO: ('\\x68656c6c6f20776f6c64', <type 'str'>)
INFO: ('hello wold', <type 'str'>)
CONTEXT: PL/Python function "test_type_conversion_bytea10"
test_type_conversion_bytea10
------------------------------
@ -358,7 +464,7 @@ CONTEXT: PL/Python function "test_type_conversion_bytea10"
SELECT * FROM test_type_conversion_bytea10('hello world', 'hello wold');
ERROR: value for domain bytea10 violates check constraint "bytea10_check"
SELECT * FROM test_type_conversion_bytea10('hello word', 'hello world');
INFO: ('\\x68656c6c6f20776f7264', <type 'str'>)
INFO: ('hello word', <type 'str'>)
CONTEXT: PL/Python function "test_type_conversion_bytea10"
ERROR: value for domain bytea10 violates check constraint "bytea10_check"
CONTEXT: while creating return value
@ -366,7 +472,7 @@ PL/Python function "test_type_conversion_bytea10"
SELECT * FROM test_type_conversion_bytea10(null, 'hello word');
ERROR: value for domain bytea10 violates check constraint "bytea10_check"
SELECT * FROM test_type_conversion_bytea10('hello word', null);
INFO: ('\\x68656c6c6f20776f7264', <type 'str'>)
INFO: ('hello word', <type 'str'>)
CONTEXT: PL/Python function "test_type_conversion_bytea10"
ERROR: value for domain bytea10 violates check constraint "bytea10_check"
CONTEXT: while creating return value

383
src/pl/plpython/plpython.c
View File

@ -1,7 +1,7 @@
/**********************************************************************
* plpython.c - python as a procedural language for PostgreSQL
*
* $PostgreSQL: pgsql/src/pl/plpython/plpython.c,v 1.127 2009/08/25 12:44:59 petere Exp $
* $PostgreSQL: pgsql/src/pl/plpython/plpython.c,v 1.128 2009/09/09 19:00:09 petere Exp $
*
*********************************************************************
*/
@ -78,7 +78,8 @@ PG_MODULE_MAGIC;
* objects.
*/
typedef PyObject *(*PLyDatumToObFunc) (const char *);
struct PLyDatumToOb;
typedef PyObject *(*PLyDatumToObFunc) (struct PLyDatumToOb*, Datum);
typedef struct PLyDatumToOb
{
@ -104,8 +105,16 @@ typedef union PLyTypeInput
/* convert PyObject to a Postgresql Datum or tuple.
* output from Python
*/
struct PLyObToDatum;
struct PLyTypeInfo;
typedef Datum (*PLyObToDatumFunc) (struct PLyTypeInfo*,
struct PLyObToDatum*,
PyObject *);
typedef struct PLyObToDatum
{
PLyObToDatumFunc func;
FmgrInfo typfunc; /* The type's input function */
Oid typoid; /* The OID of the type */
Oid typioparam;
@ -131,12 +140,11 @@ typedef struct PLyTypeInfo
{
PLyTypeInput in;
PLyTypeOutput out;
int is_rowtype;
/*
* is_rowtype can be: -1 not known yet (initial state) 0 scalar datatype
* 1 rowtype 2 rowtype, but I/O functions not set up yet
* is_rowtype can be: -1 = not known yet (initial state); 0 = scalar datatype;
* 1 = rowtype; 2 = rowtype, but I/O functions not set up yet
*/
int is_rowtype;
} PLyTypeInfo;
@ -263,12 +271,24 @@ static void PLy_output_tuple_funcs(PLyTypeInfo *, TupleDesc);
static void PLy_input_tuple_funcs(PLyTypeInfo *, TupleDesc);
/* conversion functions */
static PyObject *PLyBool_FromBool(PLyDatumToOb *arg, Datum d);
static PyObject *PLyFloat_FromFloat4(PLyDatumToOb *arg, Datum d);
static PyObject *PLyFloat_FromFloat8(PLyDatumToOb *arg, Datum d);
static PyObject *PLyFloat_FromNumeric(PLyDatumToOb *arg, Datum d);
static PyObject *PLyInt_FromInt16(PLyDatumToOb *arg, Datum d);
static PyObject *PLyInt_FromInt32(PLyDatumToOb *arg, Datum d);
static PyObject *PLyLong_FromInt64(PLyDatumToOb *arg, Datum d);
static PyObject *PLyString_FromBytea(PLyDatumToOb *arg, Datum d);
static PyObject *PLyString_FromDatum(PLyDatumToOb *arg, Datum d);
static PyObject *PLyDict_FromTuple(PLyTypeInfo *, HeapTuple, TupleDesc);
static PyObject *PLyBool_FromString(const char *);
static PyObject *PLyFloat_FromString(const char *);
static PyObject *PLyInt_FromString(const char *);
static PyObject *PLyLong_FromString(const char *);
static PyObject *PLyString_FromString(const char *);
static Datum PLyObject_ToBool(PLyTypeInfo *, PLyObToDatum *,
PyObject *);
static Datum PLyObject_ToBytea(PLyTypeInfo *, PLyObToDatum *,
PyObject *);
static Datum PLyObject_ToDatum(PLyTypeInfo *, PLyObToDatum *,
PyObject *);
static HeapTuple PLyMapping_ToTuple(PLyTypeInfo *, PyObject *);
static HeapTuple PLySequence_ToTuple(PLyTypeInfo *, PyObject *);
@ -552,8 +572,6 @@ PLy_modify_tuple(PLyProcedure *proc, PyObject *pltd, TriggerData *tdata,
for (i = 0; i < natts; i++)
{
char *src;
platt = PyList_GetItem(plkeys, i);
if (!PyString_Check(platt))
ereport(ERROR,
@ -580,20 +598,9 @@ PLy_modify_tuple(PLyProcedure *proc, PyObject *pltd, TriggerData *tdata,
}
else if (plval != Py_None)
{
plstr = PyObject_Str(plval);
if (!plstr)
PLy_elog(ERROR, "could not create string representation of Python object");
src = PyString_AsString(plstr);
modvalues[i] =
InputFunctionCall(&proc->result.out.r.atts[atti].typfunc,
src,
proc->result.out.r.atts[atti].typioparam,
tupdesc->attrs[atti]->atttypmod);
PLyObToDatum *att = &proc->result.out.r.atts[atti];
modvalues[i] = (att->func) (&proc->result, att, plval);
modnulls[i] = ' ';
Py_DECREF(plstr);
plstr = NULL;
}
else
{
@ -830,8 +837,6 @@ PLy_function_handler(FunctionCallInfo fcinfo, PLyProcedure *proc)
Datum rv;
PyObject *volatile plargs = NULL;
PyObject *volatile plrv = NULL;
PyObject *volatile plrv_so = NULL;
char *plrv_sc;
ErrorContextCallback plerrcontext;
PG_TRY();
@ -909,7 +914,6 @@ PLy_function_handler(FunctionCallInfo fcinfo, PLyProcedure *proc)
Py_XDECREF(plargs);
Py_XDECREF(plrv);
Py_XDECREF(plrv_so);
PLy_function_delete_args(proc);
@ -983,21 +987,15 @@ PLy_function_handler(FunctionCallInfo fcinfo, PLyProcedure *proc)
else
{
fcinfo->isnull = false;
plrv_so = PyObject_Str(plrv);
if (!plrv_so)
PLy_elog(ERROR, "could not create string representation of Python object");
plrv_sc = PyString_AsString(plrv_so);
rv = InputFunctionCall(&proc->result.out.d.typfunc,
plrv_sc,
proc->result.out.d.typioparam,
-1);
rv = (proc->result.out.d.func) (&proc->result,
&proc->result.out.d,
plrv);
}
}
PG_CATCH();
{
Py_XDECREF(plargs);
Py_XDECREF(plrv);
Py_XDECREF(plrv_so);
PG_RE_THROW();
}
@ -1007,7 +1005,6 @@ PLy_function_handler(FunctionCallInfo fcinfo, PLyProcedure *proc)
Py_XDECREF(plargs);
Py_DECREF(plrv);
Py_XDECREF(plrv_so);
return rv;
}
@ -1090,12 +1087,8 @@ PLy_function_build_args(FunctionCallInfo fcinfo, PLyProcedure *proc)
arg = NULL;
else
{
char *ct;
ct = OutputFunctionCall(&(proc->args[i].in.d.typfunc),
fcinfo->arg[i]);
arg = (proc->args[i].in.d.func) (ct);
pfree(ct);
arg = (proc->args[i].in.d.func) (&(proc->args[i].in.d),
fcinfo->arg[i]);
}
}
@ -1646,6 +1639,24 @@ PLy_output_datum_func2(PLyObToDatum *arg, HeapTuple typeTup)
arg->typoid = HeapTupleGetOid(typeTup);
arg->typioparam = getTypeIOParam(typeTup);
arg->typbyval = typeStruct->typbyval;
/*
* Select a conversion function to convert Python objects to
* PostgreSQL datums. Most data types can go through the generic
* function.
*/
switch (getBaseType(arg->typoid))
{
case BOOLOID:
arg->func = PLyObject_ToBool;
break;
case BYTEAOID:
arg->func = PLyObject_ToBytea;
break;
default:
arg->func = PLyObject_ToDatum;
break;
}
}
static void
@ -1672,22 +1683,31 @@ PLy_input_datum_func2(PLyDatumToOb *arg, Oid typeOid, HeapTuple typeTup)
switch (getBaseType(typeOid))
{
case BOOLOID:
arg->func = PLyBool_FromString;
arg->func = PLyBool_FromBool;
break;
case FLOAT4OID:
arg->func = PLyFloat_FromFloat4;
break;
case FLOAT8OID:
arg->func = PLyFloat_FromFloat8;
break;
case NUMERICOID:
arg->func = PLyFloat_FromString;
arg->func = PLyFloat_FromNumeric;
break;
case INT2OID:
arg->func = PLyInt_FromInt16;
break;
case INT4OID:
arg->func = PLyInt_FromString;
arg->func = PLyInt_FromInt32;
break;
case INT8OID:
arg->func = PLyLong_FromString;
arg->func = PLyLong_FromInt64;
break;
case BYTEAOID:
arg->func = PLyString_FromBytea;
break;
default:
arg->func = PLyString_FromString;
arg->func = PLyString_FromDatum;
break;
}
}
@ -1713,9 +1733,8 @@ PLy_typeinfo_dealloc(PLyTypeInfo *arg)
}
}
/* assumes that a bool is always returned as a 't' or 'f' */
static PyObject *
PLyBool_FromString(const char *src)
PLyBool_FromBool(PLyDatumToOb *arg, Datum d)
{
/*
* We would like to use Py_RETURN_TRUE and Py_RETURN_FALSE here for
@ -1723,47 +1742,75 @@ PLyBool_FromString(const char *src)
* Python >= 2.3, and we support older versions.
* http://docs.python.org/api/boolObjects.html
*/
if (src[0] == 't')
if (DatumGetBool(d))
return PyBool_FromLong(1);
return PyBool_FromLong(0);
}
static PyObject *
PLyFloat_FromString(const char *src)
PLyFloat_FromFloat4(PLyDatumToOb *arg, Datum d)
{
double v;
char *eptr;
errno = 0;
v = strtod(src, &eptr);
if (*eptr != '\0' || errno)
return NULL;
return PyFloat_FromDouble(v);
return PyFloat_FromDouble(DatumGetFloat4(d));
}
static PyObject *
PLyInt_FromString(const char *src)
PLyFloat_FromFloat8(PLyDatumToOb *arg, Datum d)
{
long v;
char *eptr;
errno = 0;
v = strtol(src, &eptr, 0);
if (*eptr != '\0' || errno)
return NULL;
return PyInt_FromLong(v);
return PyFloat_FromDouble(DatumGetFloat8(d));
}
static PyObject *
PLyLong_FromString(const char *src)
PLyFloat_FromNumeric(PLyDatumToOb *arg, Datum d)
{
return PyLong_FromString((char *) src, NULL, 0);
/*
* Numeric is cast to a PyFloat:
* This results in a loss of precision
* Would it be better to cast to PyString?
*/
Datum f = DirectFunctionCall1(numeric_float8, d);
double x = DatumGetFloat8(f);
return PyFloat_FromDouble(x);
}
static PyObject *
PLyString_FromString(const char *src)
PLyInt_FromInt16(PLyDatumToOb *arg, Datum d)
{
return PyString_FromString(src);
return PyInt_FromLong(DatumGetInt16(d));
}
static PyObject *
PLyInt_FromInt32(PLyDatumToOb *arg, Datum d)
{
return PyInt_FromLong(DatumGetInt32(d));
}
static PyObject *
PLyLong_FromInt64(PLyDatumToOb *arg, Datum d)
{
/* on 32 bit platforms "long" may be too small */
if (sizeof(int64) > sizeof(long))
return PyLong_FromLongLong(DatumGetInt64(d));
else
return PyLong_FromLong(DatumGetInt64(d));
}
static PyObject *
PLyString_FromBytea(PLyDatumToOb *arg, Datum d)
{
text *txt = DatumGetByteaP(d);
char *str = VARDATA(txt);
size_t size = VARSIZE(txt) - VARHDRSZ;
return PyString_FromStringAndSize(str, size);
}
static PyObject *
PLyString_FromDatum(PLyDatumToOb *arg, Datum d)
{
char *x = OutputFunctionCall(&arg->typfunc, d);
PyObject *r = PyString_FromString(x);
pfree(x);
return r;
}
static PyObject *
@ -1783,8 +1830,7 @@ PLyDict_FromTuple(PLyTypeInfo *info, HeapTuple tuple, TupleDesc desc)
{
for (i = 0; i < info->in.r.natts; i++)
{
char *key,
*vsrc;
char *key;
Datum vattr;
bool is_null;
PyObject *value;
@ -1799,14 +1845,7 @@ PLyDict_FromTuple(PLyTypeInfo *info, HeapTuple tuple, TupleDesc desc)
PyDict_SetItemString(dict, key, Py_None);
else
{
vsrc = OutputFunctionCall(&info->in.r.atts[i].typfunc,
vattr);
/*
* no exceptions allowed
*/
value = info->in.r.atts[i].func(vsrc);
pfree(vsrc);
value = (info->in.r.atts[i].func) (&info->in.r.atts[i], vattr);
PyDict_SetItemString(dict, key, value);
Py_DECREF(value);
}
@ -1822,6 +1861,116 @@ PLyDict_FromTuple(PLyTypeInfo *info, HeapTuple tuple, TupleDesc desc)
return dict;
}
/*
* Convert a Python object to a PostgreSQL bool datum. This can't go
* through the generic conversion function, because Python attaches a
* Boolean value to everything, more things than the PostgreSQL bool
* type can parse.
*/
static Datum
PLyObject_ToBool(PLyTypeInfo *info,
PLyObToDatum *arg,
PyObject *plrv)
{
Datum rv;
Assert(plrv != Py_None);
rv = BoolGetDatum(PyObject_IsTrue(plrv));
if (get_typtype(arg->typoid) == TYPTYPE_DOMAIN)
domain_check(rv, false, arg->typoid, &arg->typfunc.fn_extra, arg->typfunc.fn_mcxt);
return rv;
}
/*
* Convert a Python object to a PostgreSQL bytea datum. This doesn't
* go through the generic conversion function to circumvent problems
* with embedded nulls. And it's faster this way.
*/
static Datum
PLyObject_ToBytea(PLyTypeInfo *info,
PLyObToDatum *arg,
PyObject *plrv)
{
PyObject *volatile plrv_so = NULL;
Datum rv;
Assert(plrv != Py_None);
plrv_so = PyObject_Str(plrv);
if (!plrv_so)
PLy_elog(ERROR, "could not create string representation of Python object");
PG_TRY();
{
char *plrv_sc = PyString_AsString(plrv_so);
size_t len = PyString_Size(plrv_so);
size_t size = len + VARHDRSZ;
bytea *result = palloc(size);
SET_VARSIZE(result, size);
memcpy(VARDATA(result), plrv_sc, len);
rv = PointerGetDatum(result);
}
PG_CATCH();
{
Py_XDECREF(plrv_so);
PG_RE_THROW();
}
PG_END_TRY();
Py_XDECREF(plrv_so);
if (get_typtype(arg->typoid) == TYPTYPE_DOMAIN)
domain_check(rv, false, arg->typoid, &arg->typfunc.fn_extra, arg->typfunc.fn_mcxt);
return rv;
}
/*
* Generic conversion function: Convert PyObject to cstring and
* cstring into PostgreSQL type.
*/
static Datum
PLyObject_ToDatum(PLyTypeInfo *info,
PLyObToDatum *arg,
PyObject *plrv)
{
PyObject *volatile plrv_so = NULL;
Datum rv;
Assert(plrv != Py_None);
plrv_so = PyObject_Str(plrv);
if (!plrv_so)
PLy_elog(ERROR, "could not create string representation of Python object");
PG_TRY();
{
char *plrv_sc = PyString_AsString(plrv_so);
size_t plen = PyString_Size(plrv_so);
size_t slen = strlen(plrv_sc);
if (slen < plen)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("could not convert Python object into cstring: Python string representation appears to contain null bytes")));
else if (slen > plen)
elog(ERROR, "could not convert Python object into cstring: Python string longer than reported length");
rv = InputFunctionCall(&arg->typfunc, plrv_sc, arg->typioparam, -1);
}
PG_CATCH();
{
Py_XDECREF(plrv_so);
PG_RE_THROW();
}
PG_END_TRY();
Py_XDECREF(plrv_so);
return rv;
}
static HeapTuple
PLyMapping_ToTuple(PLyTypeInfo *info, PyObject *mapping)
@ -1845,11 +1994,12 @@ PLyMapping_ToTuple(PLyTypeInfo *info, PyObject *mapping)
for (i = 0; i < desc->natts; ++i)
{
char *key;
PyObject *volatile value,
*volatile so;
PyObject *volatile value;
PLyObToDatum *att;
key = NameStr(desc->attrs[i]->attname);
value = so = NULL;
value = NULL;
att = &info->out.r.atts[i];
PG_TRY();
{
value = PyMapping_GetItemString(mapping, key);
@ -1860,19 +2010,7 @@ PLyMapping_ToTuple(PLyTypeInfo *info, PyObject *mapping)
}
else if (value)
{
char *valuestr;
so = PyObject_Str(value);
if (so == NULL)
PLy_elog(ERROR, "could not compute string representation of Python object");
valuestr = PyString_AsString(so);
values[i] = InputFunctionCall(&info->out.r.atts[i].typfunc
,valuestr
,info->out.r.atts[i].typioparam
,-1);
Py_DECREF(so);
so = NULL;
values[i] = (att->func) (info, att, value);
nulls[i] = false;
}
else
@ -1887,7 +2025,6 @@ PLyMapping_ToTuple(PLyTypeInfo *info, PyObject *mapping)
}
PG_CATCH();
{
Py_XDECREF(so);
Py_XDECREF(value);
PG_RE_THROW();
}
@ -1934,10 +2071,11 @@ PLySequence_ToTuple(PLyTypeInfo *info, PyObject *sequence)
nulls = palloc(sizeof(bool) * desc->natts);
for (i = 0; i < desc->natts; ++i)
{
PyObject *volatile value,
*volatile so;
PyObject *volatile value;
PLyObToDatum *att;
value = so = NULL;
value = NULL;
att = &info->out.r.atts[i];
PG_TRY();
{
value = PySequence_GetItem(sequence, i);
@ -1949,18 +2087,7 @@ PLySequence_ToTuple(PLyTypeInfo *info, PyObject *sequence)
}
else if (value)
{
char *valuestr;
so = PyObject_Str(value);
if (so == NULL)
PLy_elog(ERROR, "could not compute string representation of Python object");
valuestr = PyString_AsString(so);
values[i] = InputFunctionCall(&info->out.r.atts[i].typfunc
,valuestr
,info->out.r.atts[i].typioparam
,-1);
Py_DECREF(so);
so = NULL;
values[i] = (att->func) (info, att, value);
nulls[i] = false;
}
@ -1969,7 +2096,6 @@ PLySequence_ToTuple(PLyTypeInfo *info, PyObject *sequence)
}
PG_CATCH();
{
Py_XDECREF(so);
Py_XDECREF(value);
PG_RE_THROW();
}
@ -2005,11 +2131,12 @@ PLyObject_ToTuple(PLyTypeInfo *info, PyObject *object)
for (i = 0; i < desc->natts; ++i)
{
char *key;
PyObject *volatile value,
*volatile so;
PyObject *volatile value;
PLyObToDatum *att;
key = NameStr(desc->attrs[i]->attname);
value = so = NULL;
value = NULL;
att = &info->out.r.atts[i];
PG_TRY();
{
value = PyObject_GetAttrString(object, key);
@ -2020,18 +2147,7 @@ PLyObject_ToTuple(PLyTypeInfo *info, PyObject *object)
}
else if (value)
{
char *valuestr;
so = PyObject_Str(value);
if (so == NULL)
PLy_elog(ERROR, "could not compute string representation of Python object");
valuestr = PyString_AsString(so);
values[i] = InputFunctionCall(&info->out.r.atts[i].typfunc
,valuestr
,info->out.r.atts[i].typioparam
,-1);
Py_DECREF(so);
so = NULL;
values[i] = (att->func) (info, att, value);
nulls[i] = false;
}
else
@ -2047,7 +2163,6 @@ PLyObject_ToTuple(PLyTypeInfo *info, PyObject *object)
}
PG_CATCH();
{
Py_XDECREF(so);
Py_XDECREF(value);
PG_RE_THROW();
}

54
src/pl/plpython/sql/plpython_types.sql
View File

@ -16,6 +16,35 @@ SELECT * FROM test_type_conversion_bool(false);
SELECT * FROM test_type_conversion_bool(null);
-- test various other ways to express Booleans in Python
CREATE FUNCTION test_type_conversion_bool_other(n int) RETURNS bool AS $$
# numbers
if n == 0:
ret = 0
elif n == 1:
ret = 5
# strings
elif n == 2:
ret = ''
elif n == 3:
ret = 'fa' # true in Python, false in PostgreSQL
# containers
elif n == 4:
ret = []
elif n == 5:
ret = [0]
plpy.info(ret, not not ret)
return ret
$$ LANGUAGE plpythonu;
SELECT * FROM test_type_conversion_bool_other(0);
SELECT * FROM test_type_conversion_bool_other(1);
SELECT * FROM test_type_conversion_bool_other(2);
SELECT * FROM test_type_conversion_bool_other(3);
SELECT * FROM test_type_conversion_bool_other(4);
SELECT * FROM test_type_conversion_bool_other(5);
CREATE FUNCTION test_type_conversion_char(x char) RETURNS char AS $$
plpy.info(x, type(x))
return x
@ -105,6 +134,7 @@ return x
$$ LANGUAGE plpythonu;
SELECT * FROM test_type_conversion_bytea('hello world');
SELECT * FROM test_type_conversion_bytea(E'null\\000byte');
SELECT * FROM test_type_conversion_bytea(null);
@ -121,8 +151,6 @@ except ValueError, e:
return 'FAILED: ' + str(e)
$$ LANGUAGE plpythonu;
/* This will currently fail because the bytea datum is presented to
Python as a string in bytea-encoding, which Python doesn't understand. */
SELECT test_type_unmarshal(x) FROM test_type_marshal() x;
@ -130,6 +158,17 @@ SELECT test_type_unmarshal(x) FROM test_type_marshal() x;
-- Domains
--
CREATE DOMAIN booltrue AS bool CHECK (VALUE IS TRUE OR VALUE IS NULL);
CREATE FUNCTION test_type_conversion_booltrue(x booltrue, y bool) RETURNS booltrue AS $$
return y
$$ LANGUAGE plpythonu;
SELECT * FROM test_type_conversion_booltrue(true, true);
SELECT * FROM test_type_conversion_booltrue(false, true);
SELECT * FROM test_type_conversion_booltrue(true, false);
CREATE DOMAIN uint2 AS int2 CHECK (VALUE >= 0);
CREATE FUNCTION test_type_conversion_uint2(x uint2, y int) RETURNS uint2 AS $$
@ -142,6 +181,17 @@ SELECT * FROM test_type_conversion_uint2(100::uint2, -50);
SELECT * FROM test_type_conversion_uint2(null, 1);
CREATE DOMAIN nnint AS int CHECK (VALUE IS NOT NULL);
CREATE FUNCTION test_type_conversion_nnint(x nnint, y int) RETURNS nnint AS $$
return y
$$ LANGUAGE plpythonu;
SELECT * FROM test_type_conversion_nnint(10, 20);
SELECT * FROM test_type_conversion_nnint(null, 20);
SELECT * FROM test_type_conversion_nnint(10, null);
CREATE DOMAIN bytea10 AS bytea CHECK (octet_length(VALUE) = 10 AND VALUE IS NOT NULL);
CREATE FUNCTION test_type_conversion_bytea10(x bytea10, y bytea) RETURNS bytea10 AS $$