Fix the log levels mapping

docs/changelog-fragments/597.bugfix.rst

@@ -0,0 +1 @@
+Fixed log level mapping to cover whole libssh range -- by :user:`Jakuje`.

src/pylibsshext/includes/callbacks.pxd

@@ -127,3 +127,10 @@ cdef extern from "libssh/callbacks.h":
     ctypedef ssh_channel_callbacks_struct * ssh_channel_callbacks
 
     int ssh_set_channel_callbacks(ssh_channel channel, ssh_channel_callbacks cb)
+
+    ctypedef void(*ssh_logging_callback)(
+        int priority,
+        const char *function,
+        const char *buffer,
+        void *userdata)
+    int ssh_set_log_callback(ssh_logging_callback cb)

src/pylibsshext/logging.pxd

@@ -0,0 +1,23 @@
+# distutils: libraries = ssh
+#
+# This file is part of the pylibssh library
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, see file LICENSE.rst in this
+# repository.
+#
+from pylibsshext.includes cimport callbacks, libssh
+
+
+cdef class Logging:
+    pass

src/pylibsshext/logging.pyx

@@ -0,0 +1,101 @@
+#
+# This file is part of the pylibssh library
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, see file LICENSE.rst in this
+# repository.
+
+import logging
+
+from pylibsshext.errors cimport LibsshSessionException
+
+
+ANSIBLE_PYLIBSSH_TRACE = 5
+
+LOG_MAP = {
+    logging.NOTSET: libssh.SSH_LOG_NONE,
+    ANSIBLE_PYLIBSSH_TRACE: libssh.SSH_LOG_TRACE,
+    logging.DEBUG: libssh.SSH_LOG_DEBUG,
+    logging.INFO: libssh.SSH_LOG_INFO,
+    logging.WARNING: libssh.SSH_LOG_WARN,
+    logging.ERROR: libssh.SSH_LOG_WARN,
+    logging.CRITICAL: libssh.SSH_LOG_WARN
+}
+
+LOG_MAP_REV = {
+    libssh.SSH_LOG_NONE: logging.NOTSET,
+    libssh.SSH_LOG_TRACE: ANSIBLE_PYLIBSSH_TRACE,
+    libssh.SSH_LOG_DEBUG: logging.DEBUG,
+    libssh.SSH_LOG_INFO: logging.INFO,
+    libssh.SSH_LOG_WARN: logging.WARNING,
+}
+
+logger = logging.getLogger("libssh")
+
+
+def add_trace_log_level():
+    level_num = ANSIBLE_PYLIBSSH_TRACE
+    level_name = "TRACE"
+    method_name = level_name.lower()
+    logger_class = logging.getLoggerClass()
+
+    if hasattr(logging, level_name):
+        raise AttributeError('{} already defined in logging module'.format(level_name))
+    if hasattr(logging, method_name):
+        raise AttributeError('{} already defined in logging module'.format(method_name))
+    if hasattr(logger_class, method_name):
+        raise AttributeError('{} already defined in logger class'.format(method_name))
+
+    def logForLevel(self, message, *args, **kwargs):
+        if self.isEnabledFor(level_num):
+            self._log(level_num, message, args, **kwargs)
+
+    def logToRoot(message, *args, **kwargs):
+        logging.log(level_num, message, *args, **kwargs)
+
+    logging.addLevelName(level_num, level_name)
+    setattr(logging, level_name, level_num)
+    setattr(logging, method_name, logToRoot)
+    setattr(logger_class, method_name, logForLevel)
+
+
+cdef void _pylibssh_log_wrapper(int priority,
+                                const char *function,
+                                const char *buffer,
+                                void *userdata) noexcept nogil:
+    with gil:
+        log_level = LOG_MAP_REV[priority]
+        logger.log(log_level, f"{buffer}")
+
+
+def set_log_callback():
+    callbacks.ssh_set_log_callback(_pylibssh_log_wrapper)
+
+
+def logging_init():
+    try:
+        add_trace_log_level()
+    except AttributeError:
+        pass
+    set_log_callback()
+
+
+def set_level(level):
+    logging_init()
+    if level in LOG_MAP.keys():
+        rc = libssh.ssh_set_log_level(LOG_MAP[level])
+        if rc != libssh.SSH_OK:
+            raise LibsshSessionException("Failed to set log level [%d] with error [%d]" % (level, rc))
+        logger.setLevel(level)
+    else:
+        raise LibsshSessionException("Invalid log level [%d]" % level)

src/pylibsshext/session.pyx

@@ -15,12 +15,14 @@
 # License along with this library; if not, see file LICENSE.rst in this
 # repository.
 import inspect
-import logging
 
 from cpython.bytes cimport PyBytes_AS_STRING
 
 from pylibsshext.channel import Channel
+
 from pylibsshext.errors cimport LibsshSessionException
+
+from pylibsshext.logging import set_level
 from pylibsshext.scp import SCP
 from pylibsshext.sftp import SFTP
 
@@ -44,15 +46,6 @@ OPTS_DIR_MAP = {
     "add_identity": libssh.SSH_OPTIONS_ADD_IDENTITY,
 }
 
-LOG_MAP = {
-    logging.NOTSET: libssh.SSH_LOG_NONE,
-    logging.DEBUG: libssh.SSH_LOG_DEBUG,
-    logging.INFO: libssh.SSH_LOG_INFO,
-    logging.WARNING: libssh.SSH_LOG_WARN,
-    logging.ERROR: libssh.SSH_LOG_WARN,
-    logging.CRITICAL: libssh.SSH_LOG_TRACE
-}
-
 KNOW_HOST_MSG_MAP = {
     libssh.SSH_KNOWN_HOSTS_CHANGED: "Host key for server has changed: ",
     libssh.SSH_KNOWN_HOSTS_OTHER: "Host key type for server has changed: ",
@@ -334,6 +327,7 @@ cdef class Session(object):
         if rc != libssh.SSH_OK:
             return
 
+        # FIXME The SHA1 hashes are non-standard -- the most common these days are SHA256 hashes for fingerprints
         rc = libssh.ssh_get_publickey_hash(srv_pubkey, libssh.SSH_PUBLICKEY_HASH_SHA1, &hash, &hash_len)
 
         cdef libssh.ssh_keytypes_e key_type = libssh.ssh_key_type(srv_pubkey)
@@ -520,12 +514,7 @@ cdef class Session(object):
         return SFTP(self)
 
     def set_log_level(self, level):
-        if level in LOG_MAP.keys():
-            rc = libssh.ssh_set_log_level(LOG_MAP[level])
-            if rc != libssh.SSH_OK:
-                raise LibsshSessionException("Failed to set log level [%d] with error [%d]" % (level, rc))
-        else:
-            raise LibsshSessionException("Invalid log level [%d]" % level)
+        set_level(level)
 
     def close(self):
         if self._libssh_session is not NULL:

tests/unit/session_test.py

@@ -2,12 +2,18 @@
 
 """Tests suite for session."""
 
+import logging
+
 import pytest
 
 from pylibsshext.errors import LibsshSessionException
+from pylibsshext.logging import ANSIBLE_PYLIBSSH_TRACE
 from pylibsshext.session import Session
 
 
+LOCALHOST = '127.0.0.1'
+
+
 def test_make_session():
     """Smoke-test Session instance creation."""
     assert Session()
@@ -18,4 +24,49 @@ def test_session_connection_refused(free_port_num):
     error_msg = '^ssh connect failed: Connection refused$'
     ssh_session = Session()
     with pytest.raises(LibsshSessionException, match=error_msg):
-        ssh_session.connect(host='127.0.0.1', port=free_port_num)
+        ssh_session.connect(host=LOCALHOST, port=free_port_num)
+
+
+def test_session_log_level_debug(caplog, free_port_num):
+    """Test setting the log level to DEBUG should reveal copyright information."""
+    ssh_session = Session()
+    ssh_session.set_log_level(logging.DEBUG)
+
+    # the connection will fail but first log lands before that
+    with pytest.raises(LibsshSessionException):
+        ssh_session.connect(host=LOCALHOST, port=free_port_num)
+
+    found_copyright = False
+    for record in caplog.records:
+        # This log message is shown at different log levels in different libssh versions
+        if record.levelname in {'DEBUG', 'INFO'} and 'and libssh contributors.' in record.msg:
+            found_copyright = True
+    assert found_copyright
+
+
+def test_session_log_level_no_log(caplog, free_port_num):
+    """Test setting the log level to NONE should be quiet."""
+    ssh_session = Session()
+    ssh_session.set_log_level(logging.NOTSET)
+
+    # the connection will fail but first log lands before that
+    with pytest.raises(LibsshSessionException):
+        ssh_session.connect(host=LOCALHOST, port=free_port_num)
+
+    assert not caplog.records
+
+
+def test_session_log_level_trace(caplog, free_port_num):
+    """Test setting the log level to TRACE should provide even more logs."""
+    ssh_session = Session()
+    ssh_session.set_log_level(ANSIBLE_PYLIBSSH_TRACE)
+
+    # the connection will fail but first log lands before that
+    with pytest.raises(LibsshSessionException):
+        ssh_session.connect(host=LOCALHOST, port=free_port_num)
+
+    found_trace = False
+    for record in caplog.records:
+        if record.levelname == 'TRACE' and 'ssh_socket_pollcallback: Poll callback on socket' in record.msg:
+            found_trace = True
+    assert found_trace