Move metadata extraction into a library function (#26198)

* Move metadata extraction into a library function
* fix the string cases to throw NotImplementedError
* Some python3 fixes
This commit is contained in:
Toshio Kuratomi 2017-06-28 18:10:26 -07:00 committed by GitHub
parent 6908038036
commit e27c2860e7
2 changed files with 222 additions and 185 deletions

View file

@ -28,9 +28,7 @@ from collections import defaultdict
from distutils.version import StrictVersion from distutils.version import StrictVersion
from pprint import pformat, pprint from pprint import pformat, pprint
import yaml from ansible.parsing.metadata import ParseError, extract_metadata
from ansible.module_utils._text import to_text
from ansible.plugins import module_loader from ansible.plugins import module_loader
@ -42,11 +40,6 @@ NONMODULE_MODULE_NAMES = frozenset(os.path.splitext(p)[0] for p in NONMODULE_PY_
DEFAULT_METADATA = {'metadata_version': '1.0', 'status': ['preview'], 'supported_by': 'community'} DEFAULT_METADATA = {'metadata_version': '1.0', 'status': ['preview'], 'supported_by': 'community'}
class ParseError(Exception):
"""Thrown when parsing a file fails"""
pass
class MissingModuleError(Exception): class MissingModuleError(Exception):
"""Thrown when unable to find a plugin""" """Thrown when unable to find a plugin"""
pass pass
@ -87,183 +80,6 @@ def parse_args(arg_string):
return action, {'version': version, 'overwrite': overwrite, 'csvfile': csvfile} return action, {'version': version, 'overwrite': overwrite, 'csvfile': csvfile}
def seek_end_of_dict(module_data, start_line, start_col, next_node_line, next_node_col):
"""Look for the end of a dict in a set of lines
We know the starting position of the dict and we know the start of the
next code node but in between there may be multiple newlines and comments.
There may also be multiple python statements on the same line (separated
by semicolons)
Examples::
ANSIBLE_METADATA = {[..]}
DOCUMENTATION = [..]
ANSIBLE_METADATA = {[..]} # Optional comments with confusing junk => {}
# Optional comments {}
DOCUMENTATION = [..]
ANSIBLE_METADATA = {
[..]
}
# Optional comments {}
DOCUMENTATION = [..]
ANSIBLE_METADATA = {[..]} ; DOCUMENTATION = [..]
ANSIBLE_METADATA = {}EOF
"""
if next_node_line is None:
# The dict is the last statement in the file
snippet = module_data.splitlines()[start_line:]
next_node_col = 0
# Include the last line in the file
last_line_offset = 0
else:
# It's somewhere in the middle so we need to separate it from the rest
snippet = module_data.splitlines()[start_line:next_node_line]
# Do not include the last line because that's where the next node
# starts
last_line_offset = 1
if next_node_col == 0:
# This handles all variants where there are only comments and blank
# lines between the dict and the next code node
# Step backwards through all the lines in the snippet
for line_idx, line in tuple(reversed(tuple(enumerate(snippet))))[last_line_offset:]:
end_col = None
# Step backwards through all the characters in the line
for col_idx, char in reversed(tuple(enumerate(c for c in line))):
if char == '}' and end_col is None:
# Potentially found the end of the dict
end_col = col_idx
elif char == '#' and end_col is not None:
# The previous '}' was part of a comment. Keep trying
end_col = None
if end_col is not None:
# Found the end!
end_line = start_line + line_idx
break
else:
# Harder cases involving multiple statements on one line
# Good Ansible Module style doesn't do this so we're just going to
# treat this as an error for now:
raise ParseError('Multiple statements per line confuses the module metadata parser.')
return end_line, end_col
def seek_end_of_string(module_data, start_line, start_col, next_node_line, next_node_col):
"""
This is much trickier than finding the end of a dict. A dict has only one
ending character, "}". Strings have four potential ending characters. We
have to parse the beginning of the string to determine what the ending
character will be.
Examples:
ANSIBLE_METADATA = '''[..]''' # Optional comment with confusing chars '''
# Optional comment with confusing chars '''
DOCUMENTATION = [..]
ANSIBLE_METADATA = '''
[..]
'''
DOCUMENTATIONS = [..]
ANSIBLE_METADATA = '''[..]''' ; DOCUMENTATION = [..]
SHORT_NAME = ANSIBLE_METADATA = '''[..]''' ; DOCUMENTATION = [..]
String marker variants:
* '[..]'
* "[..]"
* '''[..]'''
* \"\"\"[..]\"\"\"
Each of these come in u, r, and b variants:
* '[..]'
* u'[..]'
* b'[..]'
* r'[..]'
* ur'[..]'
* ru'[..]'
* br'[..]'
* b'[..]'
* rb'[..]'
"""
raise NotImplementedError('Finding end of string not yet implemented')
def extract_metadata(module_data):
"""Extract the metadata from a module
:arg module_data: Byte string containing a module's code
:returns: a tuple of metadata (a dict), line the metadata starts on,
column the metadata starts on, line the metadata ends on, column the
metadata ends on, and the names the metadata is assigned to. One of
the names the metadata is assigned to will be ANSIBLE_METADATA If no
metadata is found, the tuple will be (None, -1, -1, -1, -1, None)
"""
metadata = None
start_line = -1
start_col = -1
end_line = -1
end_col = -1
targets = None
mod_ast_tree = ast.parse(module_data)
for root_idx, child in enumerate(mod_ast_tree.body):
if isinstance(child, ast.Assign):
for target in child.targets:
if target.id == 'ANSIBLE_METADATA':
if isinstance(child.value, ast.Dict):
metadata = ast.literal_eval(child.value)
try:
# Determine where the next node starts
next_node = mod_ast_tree.body[root_idx + 1]
next_lineno = next_node.lineno
next_col_offset = next_node.col_offset
except IndexError:
# Metadata is defined in the last node of the file
next_lineno = None
next_col_offset = None
# Determine where the current metadata ends
end_line, end_col = seek_end_of_dict(module_data,
child.lineno - 1,
child.col_offset,
next_lineno,
next_col_offset)
elif isinstance(child.value, ast.Str):
metadata = yaml.safe_load(child.value.s)
end_line = seek_end_of_string(module_data)
elif isinstance(child.value, ast.Bytes):
metadata = yaml.safe_load(to_text(child.value.s, errors='surrogate_or_strict'))
end_line = seek_end_of_string(module_data)
else:
# Example:
# ANSIBLE_METADATA = 'junk'
# ANSIBLE_METADATA = { [..the real metadata..] }
continue
# Do these after the if-else so we don't pollute them in
# case this was a false positive
start_line = child.lineno - 1
start_col = child.col_offset
targets = [t.id for t in child.targets]
break
if metadata is not None:
# Once we've found the metadata we're done
break
return metadata, start_line, start_col, end_line, end_col, targets
def find_documentation(module_data): def find_documentation(module_data):
"""Find the DOCUMENTATION metadata for a module file""" """Find the DOCUMENTATION metadata for a module file"""
start_line = -1 start_line = -1

View file

@ -0,0 +1,221 @@
# (c) 2017, Toshio Kuratomi <tkuratomi@ansible.com>
#
# This file is part of Ansible
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible. If not, see <http://www.gnu.org/licenses/>.
# Make coding more python3-ish
from __future__ import (absolute_import, division, print_function)
__metaclass__ = type
import ast
import yaml
from ansible.module_utils._text import to_text
class ParseError(Exception):
"""Thrown when parsing a file fails"""
pass
def seek_end_of_dict(module_data, start_line, start_col, next_node_line, next_node_col):
"""Look for the end of a dict in a set of lines
We know the starting position of the dict and we know the start of the
next code node but in between there may be multiple newlines and comments.
There may also be multiple python statements on the same line (separated
by semicolons)
Examples::
ANSIBLE_METADATA = {[..]}
DOCUMENTATION = [..]
ANSIBLE_METADATA = {[..]} # Optional comments with confusing junk => {}
# Optional comments {}
DOCUMENTATION = [..]
ANSIBLE_METADATA = {
[..]
}
# Optional comments {}
DOCUMENTATION = [..]
ANSIBLE_METADATA = {[..]} ; DOCUMENTATION = [..]
ANSIBLE_METADATA = {}EOF
"""
if next_node_line is None:
# The dict is the last statement in the file
snippet = module_data.splitlines()[start_line:]
next_node_col = 0
# Include the last line in the file
last_line_offset = 0
else:
# It's somewhere in the middle so we need to separate it from the rest
snippet = module_data.splitlines()[start_line:next_node_line]
# Do not include the last line because that's where the next node
# starts
last_line_offset = 1
if next_node_col == 0:
# This handles all variants where there are only comments and blank
# lines between the dict and the next code node
# Step backwards through all the lines in the snippet
for line_idx, line in tuple(reversed(tuple(enumerate(snippet))))[last_line_offset:]:
end_col = None
# Step backwards through all the characters in the line
for col_idx, char in reversed(tuple(enumerate(c for c in line))):
if not isinstance(char, bytes):
# Python3 wart. slicing a byte string yields integers
char = bytes((char,))
if char == b'}' and end_col is None:
# Potentially found the end of the dict
end_col = col_idx
elif char == b'#' and end_col is not None:
# The previous '}' was part of a comment. Keep trying
end_col = None
if end_col is not None:
# Found the end!
end_line = start_line + line_idx
break
else:
raise ParseError('Unable to find the end of dictionary')
else:
# Harder cases involving multiple statements on one line
# Good Ansible Module style doesn't do this so we're just going to
# treat this as an error for now:
raise ParseError('Multiple statements per line confuses the module metadata parser.')
return end_line, end_col
def seek_end_of_string(module_data, start_line, start_col, next_node_line, next_node_col):
"""
This is much trickier than finding the end of a dict. A dict has only one
ending character, "}". Strings have four potential ending characters. We
have to parse the beginning of the string to determine what the ending
character will be.
Examples:
ANSIBLE_METADATA = '''[..]''' # Optional comment with confusing chars '''
# Optional comment with confusing chars '''
DOCUMENTATION = [..]
ANSIBLE_METADATA = '''
[..]
'''
DOCUMENTATIONS = [..]
ANSIBLE_METADATA = '''[..]''' ; DOCUMENTATION = [..]
SHORT_NAME = ANSIBLE_METADATA = '''[..]''' ; DOCUMENTATION = [..]
String marker variants:
* '[..]'
* "[..]"
* '''[..]'''
* \"\"\"[..]\"\"\"
Each of these come in u, r, and b variants:
* '[..]'
* u'[..]'
* b'[..]'
* r'[..]'
* ur'[..]'
* ru'[..]'
* br'[..]'
* b'[..]'
* rb'[..]'
"""
raise NotImplementedError('Finding end of string not yet implemented')
def extract_metadata(module_data):
"""Extract the metadata from a module
:arg module_data: Byte string containing a module's code
:returns: a tuple of metadata (a dict), line the metadata starts on,
column the metadata starts on, line the metadata ends on, column the
metadata ends on, and the names the metadata is assigned to. One of
the names the metadata is assigned to will be ANSIBLE_METADATA If no
metadata is found, the tuple will be (None, -1, -1, -1, -1, None)
"""
metadata = None
start_line = -1
start_col = -1
end_line = -1
end_col = -1
targets = None
mod_ast_tree = ast.parse(module_data)
for root_idx, child in enumerate(mod_ast_tree.body):
if isinstance(child, ast.Assign):
for target in child.targets:
if target.id == 'ANSIBLE_METADATA':
metadata = ast.literal_eval(child.value)
try:
# Determine where the next node starts
next_node = mod_ast_tree.body[root_idx + 1]
next_lineno = next_node.lineno
next_col_offset = next_node.col_offset
except IndexError:
# Metadata is defined in the last node of the file
next_lineno = None
next_col_offset = None
if isinstance(child.value, ast.Dict):
# Determine where the current metadata ends
end_line, end_col = seek_end_of_dict(module_data,
child.lineno - 1,
child.col_offset,
next_lineno,
next_col_offset)
elif isinstance(child.value, ast.Str):
metadata = yaml.safe_load(child.value.s)
end_line, end_col = seek_end_of_string(module_data,
child.lineno - 1,
child.col_offset,
next_lineno,
next_col_offset)
elif isinstance(child.value, ast.Bytes):
metadata = yaml.safe_load(to_text(child.value.s, errors='surrogate_or_strict'))
end_line, end_col = seek_end_of_string(module_data,
child.lineno - 1,
child.col_offset,
next_lineno,
next_col_offset)
else:
# Example:
# ANSIBLE_METADATA = 'junk'
# ANSIBLE_METADATA = { [..the real metadata..] }
continue
# Do these after the if-else so we don't pollute them in
# case this was a false positive
start_line = child.lineno - 1
start_col = child.col_offset
targets = [t.id for t in child.targets]
break
if metadata is not None:
# Once we've found the metadata we're done
break
return metadata, start_line, start_col, end_line, end_col, targets