Add following APIs and test cases: (#44)

*     Add following APIs and test cases:
    - get Yang module's prefix
    - get the datanode's data type
    - get the data type of the node that leafref node points to

* Add new libyang python APIs:
- get_leafref_path()
- get_leafref_type_schema()

src/sonic-yang-mgmt/sonic_yang.py

@@ -540,3 +540,122 @@ def find_data_dependencies (self, data_xpath):
  self.fail(e)
 
  return ref_list
+
+ """
+ get_module_prefix: get the prefix of a Yang module
+ input: name of the Yang module
+ output: prefix of the Yang module
+ """
+ def get_module_prefix(self, module_name):
+ prefix = ""
+ try:
+ module = self.get_module(module_name)
+ except Exception as e:
+ self.fail(e)
+ return prefix
+ else:
+ return module.prefix()
+
+ """
+ str_to_type: map string to type of node
+ input: string
+ output: type
+ """
+ def str_to_type (self, type_str):
+ mapped_type = {
+ "LY_TYPE_DER":ly.LY_TYPE_DER,
+ "LY_TYPE_BINARY":ly.LY_TYPE_BINARY,
+ "LY_TYPE_BITS":ly.LY_TYPE_BITS,
+ "LY_TYPE_BOOL":ly.LY_TYPE_BOOL,
+ "LY_TYPE_DEC64":ly.LY_TYPE_DEC64,
+ "LY_TYPE_EMPTY":ly.LY_TYPE_EMPTY,
+ "LY_TYPE_ENUM":ly.LY_TYPE_ENUM,
+ "LY_TYPE_IDENT":ly.LY_TYPE_IDENT,
+ "LY_TYPE_INST":ly.LY_TYPE_INST,
+ "LY_TYPE_LEAFREF":ly.LY_TYPE_LEAFREF,
+ "LY_TYPE_STRING":ly.LY_TYPE_STRING,
+ "LY_TYPE_UNION":ly.LY_TYPE_UNION,
+ "LY_TYPE_INT8":ly.LY_TYPE_INT8,
+ "LY_TYPE_UINT8":ly.LY_TYPE_UINT8,
+ "LY_TYPE_INT16":ly.LY_TYPE_INT16,
+ "LY_TYPE_UINT16":ly.LY_TYPE_UINT16,
+ "LY_TYPE_INT32":ly.LY_TYPE_INT32,
+ "LY_TYPE_UINT32":ly.LY_TYPE_UINT32,
+ "LY_TYPE_INT64":ly.LY_TYPE_INT64,
+ "LY_TYPE_UINT64":ly.LY_TYPE_UINT64,
+ "LY_TYPE_UNKNOWN":ly.LY_TYPE_UNKNOWN
+ }
+
+ if type_str not in mapped_type:
+ return ly.LY_TYPE_UNKNOWN
+
+ return mapped_type[type_str]
+
+ def get_data_type (self, schema_xpath):
+ try:
+ schema_node = self.find_schema_node(schema_xpath)
+ except Exception as e:
+ print("get_data_type(): Failed to find schema node from xpath: {}".format(schema_xpath))
+ self.fail(e)
+ return None
+
+ if (schema_node is not None):
+ return schema_node.subtype().type().base()
+
+ return ly.LY_TYPE_UNKNOWN
+
+ """
+ get_leafref_type: find the type of node that leafref references to
+ input: data_xpath - xpath of a data node
+ output: type of the node this leafref references to
+ """
+ def get_leafref_type (self, data_xpath):
+ data_node = self.find_data_node(data_xpath)
+ if (data_node is not None):
+ subtype = data_node.subtype()
+ if (subtype is not None):
+ if data_node.schema().subtype().type().base() != ly.LY_TYPE_LEAFREF:
+ print("get_leafref_type() node type for data xpath: {} is not LEAFREF".format(data_xpath))
+ return ly.LY_TYPE_UNKNOWN
+ else:
+ return subtype.value_type()
+
+ return ly.LY_TYPE_UNKNOWN
+
+ """
+ get_leafref_path(): find the leafref path
+ input: schema_xpath - xpath of a schema node
+ output: path value of the leafref node
+ """
+ def get_leafref_path (self, schema_xpath):
+ schema_node = self.find_schema_node(schema_xpath)
+ if (schema_node is not None):
+ subtype = schema_node.subtype()
+ if (subtype is not None):
+ if subtype.type().base() != ly.LY_TYPE_LEAFREF:
+ return None
+ else:
+ return subtype.type().info().lref().path()
+
+ return None
+
+ """
+ get_leafref_type_schema: find the type of node that leafref references to
+ input: schema_xpath - xpath of a schema node
+ output: type of the node this leafref references to
+ """
+ def get_leafref_type_schema (self, schema_xpath):
+ schema_node = self.find_schema_node(schema_xpath)
+ if (schema_node is not None):
+ subtype = schema_node.subtype()
+ if (subtype is not None):
+ if subtype.type().base() != ly.LY_TYPE_LEAFREF:
+ return None
+ else:
+ leafref_path = subtype.type().info().lref().path()
+ target = subtype.type().info().lref().target()
+ target_path = target.path()
+ target_type = self.get_data_type(target_path)
+ return target_type
+
+ return None

src/sonic-yang-mgmt/tests/libyang-python-tests/test_SonicYang.json

@@ -99,5 +99,43 @@
  "parent":"/sonic-vlan:sonic-vlan/VLAN_INTERFACE/VLAN_INTERFACE_LIST[vlanid='111'][ip-prefix='10.1.1.64/26']"},
  {"xpath":"/sonic-port:sonic-port/PORT/PORT_LIST[port_name='Ethernet9']/speed",
  "parent":"/sonic-port:sonic-port/PORT/PORT_LIST[port_name='Ethernet9']"}
- ]
+ ],
+ "prefix":[
+ {"module_name":"sonic-head", "module_prefix":"sonic-head"},
+ {"module_name":"sonic-port", "module_prefix":"port"},
+ {"module_name":"sonic-acl", "module_prefix":"acl"},
+ {"module_name":"sonic-interface", "module_prefix":"intf"},
+ {"module_name":"sonic-portchannel", "module_prefix":"lag"},
+ {"module_name":"sonic-vlan", "module_prefix":"vlan"}
+ ],
+ "data_type":[
+ {"xpath":"/sonic-port:sonic-port/sonic-port:PORT/sonic-port:PORT_LIST/sonic-port:port_name", "data_type":"LY_TYPE_STRING"},
+ {"xpath":"/sonic-vlan:sonic-vlan/sonic-vlan:VLAN_INTERFACE/sonic-vlan:VLAN_INTERFACE_LIST/sonic-vlan:vlanid", "data_type":"LY_TYPE_LEAFREF"}
+ ],
+ "leafref_type":[
+ {"xpath":"/sonic-vlan:sonic-vlan/VLAN_INTERFACE/VLAN_INTERFACE_LIST[vlanid='111'][ip-prefix='2000:f500:45:6709::/64']/vlanid", "data_type":"LY_TYPE_UINT16"},
+ {"xpath":"/sonic-interface:sonic-interface/INTERFACE/INTERFACE_LIST[interface='Ethernet8'][ip-prefix='2000:f500:40:a749::/126']/interface", "data_type":"LY_TYPE_STRING"},
+ {"xpath":"/sonic-vlan:sonic-vlan/VLAN_MEMBER/VLAN_MEMBER_LIST[vlanid='111'][port='Ethernet0']/port", "data_type":"LY_TYPE_STRING"},
+ {"xpath":"/sonic-vlan:sonic-vlan/VLAN_MEMBER/VLAN_MEMBER_LIST[vlanid='111'][port='Ethernet0']/vlanid", "data_type":"LY_TYPE_UINT16"}
+ ],
+ "leafref_type_schema":[
+ {"xpath":"/sonic-vlan:sonic-vlan/sonic-vlan:VLAN_INTERFACE/sonic-vlan:VLAN_INTERFACE_LIST/sonic-vlan:vlanid",
+ "data_type":"LY_TYPE_UINT16"},
+ {"xpath":"/sonic-interface:sonic-interface/sonic-interface:INTERFACE/sonic-interface:INTERFACE_LIST/sonic-interface:interface",
+ "data_type":"LY_TYPE_STRING"},
+ {"xpath":"/sonic-vlan:sonic-vlan/sonic-vlan:VLAN_MEMBER/sonic-vlan:VLAN_MEMBER_LIST/sonic-vlan:port",
+ "data_type":"LY_TYPE_STRING"},
+ {"xpath":"/sonic-vlan:sonic-vlan/sonic-vlan:VLAN_MEMBER/sonic-vlan:VLAN_MEMBER_LIST/sonic-vlan:vlanid",
+ "data_type":"LY_TYPE_UINT16"}
+ ],
+ "leafref_path":[
+ {"xpath":"/sonic-vlan:sonic-vlan/sonic-vlan:VLAN_INTERFACE/sonic-vlan:VLAN_INTERFACE_LIST/sonic-vlan:vlanid",
+ "leafref_path":"../../../VLAN/VLAN_LIST/vlanid"},
+ {"xpath":"/sonic-interface:sonic-interface/sonic-interface:INTERFACE/sonic-interface:INTERFACE_LIST/sonic-interface:interface",
+ "leafref_path":"/sonic-port:sonic-port/sonic-port:PORT/sonic-port:PORT_LIST/sonic-port:port_name"},
+ {"xpath":"/sonic-vlan:sonic-vlan/sonic-vlan:VLAN_MEMBER/sonic-vlan:VLAN_MEMBER_LIST/sonic-vlan:port",
+ "leafref_path":"/sonic-port:sonic-port/sonic-port:PORT/sonic-port:PORT_LIST/sonic-port:port_name"},
+ {"xpath":"/sonic-vlan:sonic-vlan/sonic-vlan:VLAN_MEMBER/sonic-vlan:VLAN_MEMBER_LIST/sonic-vlan:vlanid",
+ "leafref_path":"../../../VLAN/VLAN_LIST/vlanid"}
+ ]
 }

src/sonic-yang-mgmt/tests/libyang-python-tests/test_sonic_yang.py

@@ -214,6 +214,46 @@ def test_merge_data_tree(self, data, yang_s):
  yang_s.merge_data(data_merge_file, yang_dir)
  #yang_s.root.print_mem(ly.LYD_JSON, ly.LYP_FORMAT)
 
+ #test get module prefix
+ def test_get_module_prefix(self, yang_s, data):
+ for node in data['prefix']:
+ xpath = str(node['module_name'])
+ expected = node['module_prefix']
+ prefix = yang_s.get_module_prefix(xpath)
+ assert expected == prefix
+
+ #test get data type
+ def test_get_data_type(self, yang_s, data):
+ for node in data['data_type']:
+ xpath = str(node['xpath'])
+ expected = node['data_type']
+ expected_type = yang_s.str_to_type(expected)
+ data_type = yang_s.get_data_type(xpath)
+ assert expected_type == data_type
+
+ def test_get_leafref_type(self, yang_s, data):
+ for node in data['leafref_type']:
+ xpath = str(node['xpath'])
+ expected = node['data_type']
+ expected_type = yang_s.str_to_type(expected)
+ data_type = yang_s.get_leafref_type(xpath)
+ assert expected_type == data_type
+
+ def test_get_leafref_path(self, yang_s, data):
+ for node in data['leafref_path']:
+ xpath = str(node['xpath'])
+ expected_path = node['leafref_path']
+ path = yang_s.get_leafref_path(xpath)
+ assert expected_path == path
+
+ def test_get_leafref_type_schema(self, yang_s, data):
+ for node in data['leafref_type_schema']:
+ xpath = str(node['xpath'])
+ expected = node['data_type']
+ expected_type = yang_s.str_to_type(expected)
+ data_type = yang_s.get_leafref_type_schema(xpath)
+ assert expected_type == data_type
+
  def test_xlate_rev_xlate(self):
  # This Test is with Sonic YANG model, so create class from start
  # read the config