1 files changed, 283 insertions, 0 deletions
diff --git a/python/vyos/configtree.py b/python/vyos/configtree.py
new file mode 100644
index 000000000..d8ffaca99
--- /dev/null
+++ b/python/vyos/configtree.py
@@ -0,0 +1,283 @@
+# configtree -- a standalone VyOS config file manipulation library (Python bindings)
+# Copyright (C) 2018 VyOS maintainers and contributors
+#
+# 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, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+import re
+import json
+
+from ctypes import cdll, c_char_p, c_void_p, c_int
+
+
+def escape_backslash(string: str) -> str:
+    """Escape single backslashes in string that are not in escape sequence"""
+    p = re.compile(r'(?<!\\)[\\](?!b|f|n|r|t|\\[^bfnrt])')
+    result = p.sub(r'\\\\', string)
+    return result
+
+def extract_version(s):
+    """ Extract the version string from the config string """
+    t = re.split('(^//)', s, maxsplit=1, flags=re.MULTILINE)
+    return (s, ''.join(t[1:]))
+
+def check_path(path):
+    # Necessary type checking
+    if not isinstance(path, list):
+        raise TypeError("Expected a list, got a {}".format(type(path)))
+    else:
+        pass
+
+
+class ConfigTreeError(Exception):
+    pass
+
+
+class ConfigTree(object):
+    def __init__(self, config_string, libpath='/usr/lib/libvyosconfig.so.0'):
+        self.__config = None
+        self.__lib = cdll.LoadLibrary(libpath)
+
+        # Import functions
+        self.__from_string = self.__lib.from_string
+        self.__from_string.argtypes = [c_char_p]
+        self.__from_string.restype = c_void_p
+
+        self.__get_error = self.__lib.get_error
+        self.__get_error.argtypes = []
+        self.__get_error.restype = c_char_p
+
+        self.__to_string = self.__lib.to_string
+        self.__to_string.argtypes = [c_void_p]
+        self.__to_string.restype = c_char_p
+
+        self.__to_commands = self.__lib.to_commands
+        self.__to_commands.argtypes = [c_void_p]
+        self.__to_commands.restype = c_char_p
+
+        self.__to_json = self.__lib.to_json
+        self.__to_json.argtypes = [c_void_p]
+        self.__to_json.restype = c_char_p
+
+        self.__to_json_ast = self.__lib.to_json_ast
+        self.__to_json_ast.argtypes = [c_void_p]
+        self.__to_json_ast.restype = c_char_p
+
+        self.__set_add_value = self.__lib.set_add_value
+        self.__set_add_value.argtypes = [c_void_p, c_char_p, c_char_p]
+        self.__set_add_value.restype = c_int
+
+        self.__delete_value = self.__lib.delete_value
+        self.__delete_value.argtypes = [c_void_p, c_char_p, c_char_p]
+        self.__delete_value.restype = c_int
+
+        self.__delete = self.__lib.delete_node
+        self.__delete.argtypes = [c_void_p, c_char_p]
+        self.__delete.restype = c_int
+
+        self.__rename = self.__lib.rename_node
+        self.__rename.argtypes = [c_void_p, c_char_p, c_char_p]
+        self.__rename.restype = c_int
+
+        self.__copy = self.__lib.copy_node
+        self.__copy.argtypes = [c_void_p, c_char_p, c_char_p]
+        self.__copy.restype = c_int
+
+        self.__set_replace_value = self.__lib.set_replace_value
+        self.__set_replace_value.argtypes = [c_void_p, c_char_p, c_char_p]
+        self.__set_replace_value.restype = c_int
+
+        self.__set_valueless = self.__lib.set_valueless
+        self.__set_valueless.argtypes = [c_void_p, c_char_p]
+        self.__set_valueless.restype = c_int
+
+        self.__exists = self.__lib.exists
+        self.__exists.argtypes = [c_void_p, c_char_p]
+        self.__exists.restype = c_int
+
+        self.__list_nodes = self.__lib.list_nodes
+        self.__list_nodes.argtypes = [c_void_p, c_char_p]
+        self.__list_nodes.restype = c_char_p
+
+        self.__return_value = self.__lib.return_value
+        self.__return_value.argtypes = [c_void_p, c_char_p]
+        self.__return_value.restype = c_char_p
+
+        self.__return_values = self.__lib.return_values
+        self.__return_values.argtypes = [c_void_p, c_char_p]
+        self.__return_values.restype = c_char_p
+
+        self.__is_tag = self.__lib.is_tag
+        self.__is_tag.argtypes = [c_void_p, c_char_p]
+        self.__is_tag.restype = c_int
+
+        self.__set_tag = self.__lib.set_tag
+        self.__set_tag.argtypes = [c_void_p, c_char_p]
+        self.__set_tag.restype = c_int
+
+        self.__destroy = self.__lib.destroy
+        self.__destroy.argtypes = [c_void_p]
+
+        config_section, version_section = extract_version(config_string)
+        config_section = escape_backslash(config_section)
+        config = self.__from_string(config_section.encode())
+        if config is None:
+            msg = self.__get_error().decode()
+            raise ValueError("Failed to parse config: {0}".format(msg))
+        else:
+            self.__config = config
+            self.__version = version_section
+
+    def __del__(self):
+        if self.__config is not None:
+            self.__destroy(self.__config)
+
+    def __str__(self):
+        return self.to_string()
+
+    def to_string(self):
+        config_string = self.__to_string(self.__config).decode()
+        config_string = "{0}\n{1}".format(config_string, self.__version)
+        return config_string
+
+    def to_commands(self):
+        return self.__to_commands(self.__config).decode()
+
+    def to_json(self):
+        return self.__to_json(self.__config).decode()
+
+    def to_json_ast(self):
+        return self.__to_json_ast(self.__config).decode()
+
+    def set(self, path, value=None, replace=True):
+        """Set new entry in VyOS configuration.
+        path: configuration path e.g. 'system dns forwarding listen-address'
+        value: value to be added to node, e.g. '172.18.254.201'
+        replace: True: current occurance will be replaced
+                 False: new value will be appended to current occurances - use
+                 this for adding values to a multi node
+        """
+
+        check_path(path)
+        path_str = " ".join(map(str, path)).encode()
+
+        if value is None:
+            self.__set_valueless(self.__config, path_str)
+        else:
+            if replace:
+                self.__set_replace_value(self.__config, path_str, str(value).encode())
+            else:
+                self.__set_add_value(self.__config, path_str, str(value).encode())
+
+    def delete(self, path):
+        check_path(path)
+        path_str = " ".join(map(str, path)).encode()
+
+        self.__delete(self.__config, path_str)
+
+    def delete_value(self, path, value):
+        check_path(path)
+        path_str = " ".join(map(str, path)).encode()
+
+        self.__delete_value(self.__config, path_str, value.encode())
+
+    def rename(self, path, new_name):
+        check_path(path)
+        path_str = " ".join(map(str, path)).encode()
+        newname_str = new_name.encode()
+
+        # Check if a node with intended new name already exists
+        new_path = path[:-1] + [new_name]
+        if self.exists(new_path):
+            raise ConfigTreeError()
+        res = self.__rename(self.__config, path_str, newname_str)
+        if (res != 0):
+            raise ConfigTreeError("Path [{}] doesn't exist".format(path))
+
+    def copy(self, old_path, new_path):
+        check_path(old_path)
+        check_path(new_path)
+        oldpath_str = " ".join(map(str, old_path)).encode()
+        newpath_str = " ".join(map(str, new_path)).encode()
+
+        # Check if a node with intended new name already exists
+        if self.exists(new_path):
+            raise ConfigTreeError()
+        res = self.__copy(self.__config, oldpath_str, newpath_str)
+        if (res != 0):
+            raise ConfigTreeError("Path [{}] doesn't exist".format(old_path))
+
+    def exists(self, path):
+        check_path(path)
+        path_str = " ".join(map(str, path)).encode()
+
+        res = self.__exists(self.__config, path_str)
+        if (res == 0):
+            return False
+        else:
+            return True
+
+    def list_nodes(self, path):
+        check_path(path)
+        path_str = " ".join(map(str, path)).encode()
+
+        res_json = self.__list_nodes(self.__config, path_str).decode()
+        res = json.loads(res_json)
+
+        if res is None:
+            raise ConfigTreeError("Path [{}] doesn't exist".format(path_str))
+        else:
+            return res
+
+    def return_value(self, path):
+        check_path(path)
+        path_str = " ".join(map(str, path)).encode()
+
+        res_json = self.__return_value(self.__config, path_str).decode()
+        res = json.loads(res_json)
+
+        if res is None:
+            raise ConfigTreeError("Path [{}] doesn't exist".format(path_str))
+        else:
+            return res
+
+    def return_values(self, path):
+        check_path(path)
+        path_str = " ".join(map(str, path)).encode()
+
+        res_json = self.__return_values(self.__config, path_str).decode()
+        res = json.loads(res_json)
+
+        if res is None:
+            raise ConfigTreeError("Path [{}] doesn't exist".format(path_str))
+        else:
+            return res
+
+    def is_tag(self, path):
+        check_path(path)
+        path_str = " ".join(map(str, path)).encode()
+
+        res = self.__is_tag(self.__config, path_str)
+        if (res >= 1):
+            return True
+        else:
+            return False
+
+    def set_tag(self, path):
+        check_path(path)
+        path_str = " ".join(map(str, path)).encode()
+
+        res = self.__set_tag(self.__config, path_str)
+        if (res == 0):
+            return True
+        else:
+            raise ConfigTreeError("Path [{}] doesn't exist".format(path_str))
+