# Copyright (C) 2018-2019 The Software Heritage developers
# See the AUTHORS file at the top-level directory of this distribution
# License: GNU General Public License version 3, or any later version
# See top-level LICENSE file for more information
import click
import dulwich.repo
import os
import sys
from functools import partial
from urllib.parse import urlparse
from swh.model import hashutil
from swh.model import identifiers as pids
from swh.model.exceptions import ValidationError
from swh.model.from_disk import Content, Directory
CONTEXT_SETTINGS = dict(help_option_names=['-h', '--help'])
# Mapping between dulwich types and Software Heritage ones. Used by snapshot ID
# computation.
_DULWICH_TYPES = {
b'blob': 'content',
b'tree': 'directory',
b'commit': 'revision',
b'tag': 'release',
}
class PidParamType(click.ParamType):
name = 'persistent identifier'
def convert(self, value, param, ctx):
try:
pids.parse_persistent_identifier(value)
return value # return as string, as we need just that
except ValidationError as e:
self.fail('%s is not a valid PID. %s.' % (value, e), param, ctx)
def pid_of_file(path):
object = Content.from_file(path=path).get_data()
return pids.persistent_identifier(pids.CONTENT, object)
def pid_of_dir(path):
object = Directory.from_disk(path=path).get_data()
return pids.persistent_identifier(pids.DIRECTORY, object)
def pid_of_origin(url):
pid = pids.PersistentId(object_type='origin',
object_id=pids.origin_identifier({'url': url}))
return str(pid)
def pid_of_git_repo(path):
repo = dulwich.repo.Repo(path)
branches = {}
for ref, target in repo.refs.as_dict().items():
obj = repo[target]
if obj:
branches[ref] = {
'target': hashutil.bytehex_to_hash(target),
'target_type': _DULWICH_TYPES[obj.type_name],
}
else:
branches[ref] = None
for ref, target in repo.refs.get_symrefs().items():
branches[ref] = {
'target': target,
'target_type': 'alias',
}
snapshot = {'branches': branches}
pid = pids.PersistentId(object_type='snapshot',
object_id=pids.snapshot_identifier(snapshot))
return str(pid)
def identify_object(obj_type, follow_symlinks, obj):
if obj_type == 'auto':
if os.path.isfile(obj):
obj_type = 'content'
elif os.path.isdir(obj):
obj_type = 'directory'
else:
try: # URL parsing
if urlparse(obj).scheme:
obj_type = 'origin'
else:
raise ValueError
except ValueError:
raise click.BadParameter('cannot detect object type for %s' %
obj)
pid = None
if obj_type in ['content', 'directory']:
path = obj.encode(sys.getfilesystemencoding())
if follow_symlinks and os.path.islink(obj):
path = os.path.realpath(obj)
if obj_type == 'content':
pid = pid_of_file(path)
elif obj_type == 'directory':
pid = pid_of_dir(path)
elif obj_type == 'origin':
pid = pid_of_origin(obj)
elif obj_type == 'snapshot':
pid = pid_of_git_repo(obj)
else: # shouldn't happen, due to option validation
raise click.BadParameter('invalid object type: ' + obj_type)
# note: we return original obj instead of path here, to preserve user-given
# file name in output
return (obj, pid)
@click.command(context_settings=CONTEXT_SETTINGS)
@click.option('--dereference/--no-dereference', 'follow_symlinks',
default=True,
help='follow (or not) symlinks for OBJECTS passed as arguments '
+ '(default: follow)')
@click.option('--filename/--no-filename', 'show_filename', default=True,
help='show/hide file name (default: show)')
@click.option('--type', '-t', 'obj_type', default='auto',
type=click.Choice(['auto', 'content', 'directory', 'origin',
'snapshot']),
help='type of object to identify (default: auto)')
@click.option('--verify', '-v', metavar='PID', type=PidParamType(),
help='reference identifier to be compared with computed one')
@click.argument('objects', nargs=-1, required=True)
def identify(obj_type, verify, show_filename, follow_symlinks, objects):
"""Compute the Software Heritage persistent identifier (PID) for the given
source code object(s).
For more details about Software Heritage PIDs see:
\b
https://docs.softwareheritage.org/devel/swh-model/persistent-identifiers.html
\b
Examples:
\b
$ swh identify fork.c kmod.c sched/deadline.c
swh:1:cnt:2e391c754ae730bd2d8520c2ab497c403220c6e3 fork.c
swh:1:cnt:0277d1216f80ae1adeed84a686ed34c9b2931fc2 kmod.c
swh:1:cnt:57b939c81bce5d06fa587df8915f05affbe22b82 sched/deadline.c
\b
$ swh identify --no-filename /usr/src/linux/kernel/
swh:1:dir:f9f858a48d663b3809c9e2f336412717496202ab
\b
$ git clone --mirror https://forge.softwareheritage.org/source/helloworld.git
$ swh identify --type snapshot helloworld.git/
swh:1:snp:510aa88bdc517345d258c1fc2babcd0e1f905e93 helloworld.git
""" # NoQA # overlong lines in shell examples are fine
if verify and len(objects) != 1:
raise click.BadParameter('verification requires a single object')
results = map(partial(identify_object, obj_type, follow_symlinks), objects)
if verify:
pid = next(results)[1]
if verify == pid:
click.echo('PID match: %s' % pid)
sys.exit(0)
else:
click.echo('PID mismatch: %s != %s' % (verify, pid))
sys.exit(1)
else:
for (obj, pid) in results:
msg = pid
if show_filename:
msg = '%s\t%s' % (pid, os.fsdecode(obj))
click.echo(msg)
if __name__ == '__main__':
identify()