Added ConnectionInfo.dsn_parameters attributeinfo-dsn-params

4 files changed, 84 insertions, 23 deletions

diff --git a/doc/src/connection.rst b/doc/src/connection.rst
index 95b858d..b31c2d2 100644
--- a/doc/src/connection.rst
+++ b/doc/src/connection.rst
@@ -614,29 +614,6 @@ The ``connection`` class
 
 
     .. index::
-        pair: Connection; Parameters
-
-    .. method:: get_dsn_parameters()
-
-        Get the effective dsn parameters for the connection as a dictionary.
-
-        The *password* parameter is removed from the result.
-
-        Example::
-
-            >>> conn.get_dsn_parameters()
-            {'dbname': 'test', 'user': 'postgres', 'port': '5432', 'sslmode': 'prefer'}
-
-        Requires libpq >= 9.3.
-
-        .. seealso:: libpq docs for `PQconninfo()`__ for details.
-
-            .. __: https://www.postgresql.org/docs/current/static/libpq-connect.html#LIBPQ-PQCONNINFO
-
-        .. versionadded:: 2.7
-
-
-    .. index::
         pair: Connection; Status
 
     .. attribute:: status
@@ -882,6 +859,32 @@ The ``connection`` class
         .. versionadded:: 2.0.12
 
 
+    .. index::
+        pair: Connection; Parameters
+
+    .. method:: get_dsn_parameters()
+
+        Also available as `~connection.info`\ `!.`\
+        `~psycopg2.extensions.ConnectionInfo.dsn_parameters`.
+
+        Get the effective dsn parameters for the connection as a dictionary.
+
+        The *password* parameter is removed from the result.
+
+        Example::
+
+            >>> conn.get_dsn_parameters()
+            {'dbname': 'test', 'user': 'postgres', 'port': '5432', 'sslmode': 'prefer'}
+
+        Requires libpq >= 9.3.
+
+        .. seealso:: libpq docs for `PQconninfo()`__ for details.
+
+            .. __: https://www.postgresql.org/docs/current/static/libpq-connect.html#LIBPQ-PQCONNINFO
+
+        .. versionadded:: 2.7
+
+
 .. testcode::
     :hide:
 
diff --git a/doc/src/extensions.rst b/doc/src/extensions.rst
index ee45bec..22d9b5d 100644
--- a/doc/src/extensions.rst
+++ b/doc/src/extensions.rst
@@ -165,6 +165,15 @@ introspection etc.
     .. autoattribute:: host
     .. autoattribute:: port
     .. autoattribute:: options
+    .. autoattribute:: dsn_parameters
+
+        Example::
+
+            >>> conn.info.dsn_parameters
+            {'dbname': 'test', 'user': 'postgres', 'port': '5432', 'sslmode': 'prefer'}
+
+        Requires libpq >= 9.3.
+
     .. autoattribute:: status
     .. autoattribute:: transaction_status
     .. automethod:: parameter_status(name)
diff --git a/psycopg/conninfo_type.c b/psycopg/conninfo_type.c
index af099d4..a74e792 100644
--- a/psycopg/conninfo_type.c
+++ b/psycopg/conninfo_type.c
@@ -166,6 +166,46 @@ options_get(connInfoObject *self)
 }
 
 
+static const char dsn_parameters_doc[] =
+"The effective connection parameters.\n"
+"\n"
+":type: `!dict`\n"
+"\n"
+"The results include values which weren't explicitly set by the connection\n"
+"string, such as defaults, environment variables, etc.\n"
+"The *password* parameter is removed from the results.\n"
+"\n"
+".. seealso:: libpq docs for `PQconninfo()`__ for details.\n"
+".. __: https://www.postgresql.org/docs/current/libpq-connect.html"
+    "#LIBPQ-PQCONNINFO";
+
+static PyObject *
+dsn_parameters_get(connInfoObject *self)
+{
+#if PG_VERSION_NUM >= 90300
+    PyObject *res = NULL;
+    PQconninfoOption *options = NULL;
+
+    EXC_IF_CONN_CLOSED(self->conn);
+
+    if (!(options = PQconninfo(self->conn->pgconn))) {
+        PyErr_NoMemory();
+        goto exit;
+    }
+
+    res = psycopg_dict_from_conninfo_options(options, /* include_password = */ 0);
+
+exit:
+    PQconninfoFree(options);
+
+    return res;
+#else
+    PyErr_SetString(NotSupportedError, "PQconninfo not available in libpq < 9.3");
+    return NULL;
+#endif
+}
+
+
 static const char status_doc[] =
 "The status of the connection.\n"
 "\n"
@@ -497,6 +537,8 @@ static struct PyGetSetDef connInfoObject_getsets[] = {
     { "host", (getter)host_get, NULL, (char *)host_doc },
     { "port", (getter)port_get, NULL, (char *)port_doc },
     { "options", (getter)options_get, NULL, (char *)options_doc },
+    { "dsn_parameters", (getter)dsn_parameters_get, NULL,
+        (char *)dsn_parameters_doc },
     { "status", (getter)status_get, NULL, (char *)status_doc },
     { "transaction_status", (getter)transaction_status_get, NULL,
         (char *)transaction_status_doc },
diff --git a/tests/test_connection.py b/tests/test_connection.py
index e60b7dd..ea74e1e 100755
--- a/tests/test_connection.py
+++ b/tests/test_connection.py
@@ -1752,6 +1752,13 @@ class TestConnectionInfo(ConnectingTestCase):
         self.assert_(isinstance(self.conn.info.options, str))
         self.assert_(self.bconn.info.options is None)
 
+    @skip_before_libpq(9, 3)
+    def test_dsn_parameters(self):
+        d = self.conn.info.dsn_parameters
+        self.assert_(isinstance(d, dict))
+        self.assertEqual(d['dbname'], dbname)  # the only param we can check reliably
+        self.assert_('password' not in d, d)
+
     def test_status(self):
         self.assertEqual(self.conn.info.status, 0)
         self.assertEqual(self.bconn.info.status, 1)