Add C date loader

8x faster than the Python loader

diff --git a/psycopg3_c/psycopg3_c/_psycopg3.pyx b/psycopg3_c/psycopg3_c/_psycopg3.pyx
index e6c34397bf126b028624ff84f22c5ce28c4a2420..520a303ec42bdf1d7b3f8863f10d46a94f1f91d6 100644 (file)
--- a/psycopg3_c/psycopg3_c/_psycopg3.pyx
+++ b/psycopg3_c/psycopg3_c/_psycopg3.pyx
@@ -27,6 +27,7 @@ include "_psycopg3/copy.pyx"
 include "_psycopg3/generators.pyx"
 include "_psycopg3/transform.pyx"
 
+include "types/date.pyx"
 include "types/numeric.pyx"
 include "types/singletons.pyx"
 include "types/text.pyx"

diff --git a/psycopg3_c/psycopg3_c/types/date.pyx b/psycopg3_c/psycopg3_c/types/date.pyx
new file mode 100644 (file)
index 0000000..fa97a4e
--- /dev/null
+++ b/psycopg3_c/psycopg3_c/types/date.pyx
@@ -0,0 +1,80 @@
+"""
+Cython adapters for date/time types.
+"""
+
+# Copyright (C) 2021 The Psycopg Team
+
+
+from cpython.datetime cimport import_datetime, date_new
+
+from psycopg3 import errors as e
+
+
+# Initialise the datetime C API
+import_datetime()
+
+DEF ORDER_YMD = 0
+DEF ORDER_DMY = 1
+DEF ORDER_MDY = 2
+
+
+@cython.final
+cdef class DateLoader(CLoader):
+
+    format = PQ_TEXT
+    cdef int _order
+
+    def __init__(self, oid: int, context: Optional[AdaptContext] = None):
+        super().__init__(oid, context)
+
+        cdef const char *ds = _get_datestyle(self._pgconn)
+        if ds[0] == b'I':  # ISO
+            self._order = ORDER_YMD
+        elif ds[0] == b'G':  # German
+            self._order = ORDER_DMY
+        elif ds[0] == b'S' or ds[0] == b'P':  # SQL or Postgres
+            self._order = (
+                ORDER_DMY if ds.endswith(b"DMY") else ORDER_MDY
+            )
+        else:
+            raise e.InterfaceError(f"unexpected DateStyle: {ds.decode('ascii')}")
+
+    cdef object cload(self, const char *data, size_t length):
+        if length != 10:
+            s = bytes(data).decode("utf8", "replace")
+            raise e.DataError(f"date not supported: {s!r}")
+
+        cdef int vals[3]
+        vals[0] = vals[1] = vals[2] = 0
+
+        cdef size_t i
+        cdef int ival = 0
+        for i in range(length):
+            if b'0' <= data[i] <= b'9':
+                vals[ival] = vals[ival] * 10 + (data[i] - <char>b'0')
+            else:
+                ival += 1
+                if ival >= 3:
+                    s = bytes(data).decode("utf8", "replace")
+                    raise e.DataError(f"can't parse date {s!r}")
+
+        try:
+            if self._order == ORDER_YMD:
+                return date_new(vals[0], vals[1], vals[2])
+            elif self._order == ORDER_DMY:
+                return date_new(vals[2], vals[1], vals[0])
+            else:
+                return date_new(vals[2], vals[0], vals[1])
+        except ValueError as ex:
+            s = bytes(data).decode("utf8", "replace")
+            raise e.DataError(f"can't manage date {s!r}: {ex}") from None
+
+
+cdef const char *_get_datestyle(pq.PGconn pgconn):
+    cdef const char *ds
+    if pgconn is not None:
+        ds = libpq.PQparameterStatus(pgconn._pgconn_ptr, b"DateStyle")
+        if ds is not NULL and ds[0]:
+            return ds
+
+    return b"ISO, DMY"