morro

sqlalchemy/dialects/postgresql/pypostgresql.py

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+"""Support for the PostgreSQL database via py-postgresql.
+
+Connecting
+----------
+
+URLs are of the form `postgresql+pypostgresql://user@password@host:port/dbname[?key=value&key=value...]`.
+
+
+"""
+from sqlalchemy.engine import default
+import decimal
+from sqlalchemy import util
+from sqlalchemy import types as sqltypes
+from sqlalchemy.dialects.postgresql.base import PGDialect, PGExecutionContext
+from sqlalchemy import processors
+
+class PGNumeric(sqltypes.Numeric):
+    def bind_processor(self, dialect):
+        return processors.to_str
+
+    def result_processor(self, dialect, coltype):
+        if self.asdecimal:
+            return None
+        else:
+            return processors.to_float
+
+class PGExecutionContext_pypostgresql(PGExecutionContext):
+    pass
+
+class PGDialect_pypostgresql(PGDialect):
+    driver = 'pypostgresql'
+
+    supports_unicode_statements = True
+    supports_unicode_binds = True
+    description_encoding = None
+    default_paramstyle = 'pyformat'
+
+    # requires trunk version to support sane rowcounts
+    # TODO: use dbapi version information to set this flag appropariately
+    supports_sane_rowcount = True
+    supports_sane_multi_rowcount = False
+
+    execution_ctx_cls = PGExecutionContext_pypostgresql
+    colspecs = util.update_copy(
+        PGDialect.colspecs,
+        {
+            sqltypes.Numeric : PGNumeric,
+            sqltypes.Float: sqltypes.Float,  # prevents PGNumeric from being used
+        }
+    )
+
+    @classmethod
+    def dbapi(cls):
+        from postgresql.driver import dbapi20
+        return dbapi20
+
+    def create_connect_args(self, url):
+        opts = url.translate_connect_args(username='user')
+        if 'port' in opts:
+            opts['port'] = int(opts['port'])
+        else:
+            opts['port'] = 5432
+        opts.update(url.query)
+        return ([], opts)
+
+    def is_disconnect(self, e):
+        return "connection is closed" in str(e)
+
+dialect = PGDialect_pypostgresql