automation: perform tasks on remote machines
Sometimes you don't have access to a machine in order to
do something. For example, you may not have access to a Windows
machine required to build Windows binaries or run tests on that
platform.
This commit introduces a pile of code intended to help
"automate" common tasks, like building release artifacts.
In its current form, the automation code provides functionality
for performing tasks on Windows EC2 instances.
The hgautomation.aws module provides functionality for integrating
with AWS. It manages EC2 resources such as IAM roles, EC2
security groups, AMIs, and instances.
The hgautomation.windows module provides a higher-level
interface for performing tasks on remote Windows machines.
The hgautomation.cli module provides a command-line interface to
these higher-level primitives.
I attempted to structure Windows remote machine interaction
around Windows Remoting / PowerShell. This is kinda/sorta like
SSH + shell, but for Windows. In theory, most of the functionality
is cloud provider agnostic, as we should be able to use any
established WinRM connection to interact with a remote. In
reality, we're tightly coupled to AWS at the moment because
I didn't want to prematurely add abstractions for a 2nd cloud
provider. (1 was hard enough to implement.)
In the aws module is code for creating an image with a fully
functional Mercurial development environment. It contains VC9,
VC2017, msys, and other dependencies. The image is fully capable
of building all the existing Mercurial release artifacts and
running tests.
There are a few things that don't work. For example, running
Windows tests with Python 3. But building the Windows release
artifacts does work. And that was an impetus for this work.
(Although we don't yet support code signing.)
Getting this functionality to work was extremely time consuming.
It took hours debugging permissions failures and other wonky
behavior due to PowerShell Remoting. (The permissions model for
PowerShell is crazy and you brush up against all kinds of
issues because of the user/privileges of the user running
the PowerShell and the permissions of the PowerShell session
itself.)
The functionality around AWS resource management could use some
improving. In theory we support shared tenancy via resource
name prefixing. In reality, we don't offer a way to configure
this.
Speaking of AWS resource management, I thought about using a tool
like Terraform to manage resources. But at our scale, writing a
few dozen lines of code to manage resources seemed acceptable.
Maybe we should reconsider this if things grow out of control.
Time will tell.
Currently, emphasis is placed on Windows. But I only started
there because it was likely to be the most difficult to implement.
It should be relatively trivial to automate tasks on remote Linux
machines. In fact, I have a ~1 year old script to run tests on a
remote EC2 instance. I will likely be porting that to this new
"framework" in the near future.
# no-check-commit because foo_bar functions
Differential Revision: https://phab.mercurial-scm.org/D6142
# synthrepo.py - repo synthesis
#
# Copyright 2012 Facebook
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
'''synthesize structurally interesting change history
This extension is useful for creating a repository with properties
that are statistically similar to an existing repository. During
analysis, a simple probability table is constructed from the history
of an existing repository. During synthesis, these properties are
reconstructed.
Properties that are analyzed and synthesized include the following:
- Lines added or removed when an existing file is modified
- Number and sizes of files added
- Number of files removed
- Line lengths
- Topological distance to parent changeset(s)
- Probability of a commit being a merge
- Probability of a newly added file being added to a new directory
- Interarrival time, and time zone, of commits
- Number of files in each directory
A few obvious properties that are not currently handled realistically:
- Merges are treated as regular commits with two parents, which is not
realistic
- Modifications are not treated as operations on hunks of lines, but
as insertions and deletions of randomly chosen single lines
- Committer ID (always random)
- Executability of files
- Symlinks and binary files are ignored
'''
from __future__ import absolute_import
import bisect
import collections
import itertools
import json
import os
import random
import sys
import time
from mercurial.i18n import _
from mercurial.node import (
nullid,
nullrev,
short,
)
from mercurial import (
context,
diffutil,
error,
hg,
patch,
registrar,
scmutil,
)
from mercurial.utils import (
dateutil,
)
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'ships-with-hg-core'
cmdtable = {}
command = registrar.command(cmdtable)
newfile = {'new fi', 'rename', 'copy f', 'copy t'}
def zerodict():
return collections.defaultdict(lambda: 0)
def roundto(x, k):
if x > k * 2:
return int(round(x / float(k)) * k)
return int(round(x))
def parsegitdiff(lines):
filename, mar, lineadd, lineremove = None, None, zerodict(), 0
binary = False
for line in lines:
start = line[:6]
if start == 'diff -':
if filename:
yield filename, mar, lineadd, lineremove, binary
mar, lineadd, lineremove, binary = 'm', zerodict(), 0, False
filename = patch.gitre.match(line).group(1)
elif start in newfile:
mar = 'a'
elif start == 'GIT bi':
binary = True
elif start == 'delete':
mar = 'r'
elif start:
s = start[0]
if s == '-' and not line.startswith('--- '):
lineremove += 1
elif s == '+' and not line.startswith('+++ '):
lineadd[roundto(len(line) - 1, 5)] += 1
if filename:
yield filename, mar, lineadd, lineremove, binary
@command('analyze',
[('o', 'output', '', _('write output to given file'), _('FILE')),
('r', 'rev', [], _('analyze specified revisions'), _('REV'))],
_('hg analyze'), optionalrepo=True)
def analyze(ui, repo, *revs, **opts):
'''create a simple model of a repository to use for later synthesis
This command examines every changeset in the given range (or all
of history if none are specified) and creates a simple statistical
model of the history of the repository. It also measures the directory
structure of the repository as checked out.
The model is written out to a JSON file, and can be used by
:hg:`synthesize` to create or augment a repository with synthetic
commits that have a structure that is statistically similar to the
analyzed repository.
'''
root = repo.root
if not root.endswith(os.path.sep):
root += os.path.sep
revs = list(revs)
revs.extend(opts['rev'])
if not revs:
revs = [':']
output = opts['output']
if not output:
output = os.path.basename(root) + '.json'
if output == '-':
fp = sys.stdout
else:
fp = open(output, 'w')
# Always obtain file counts of each directory in the given root directory.
def onerror(e):
ui.warn(_('error walking directory structure: %s\n') % e)
dirs = {}
rootprefixlen = len(root)
for dirpath, dirnames, filenames in os.walk(root, onerror=onerror):
dirpathfromroot = dirpath[rootprefixlen:]
dirs[dirpathfromroot] = len(filenames)
if '.hg' in dirnames:
dirnames.remove('.hg')
lineschanged = zerodict()
children = zerodict()
p1distance = zerodict()
p2distance = zerodict()
linesinfilesadded = zerodict()
fileschanged = zerodict()
filesadded = zerodict()
filesremoved = zerodict()
linelengths = zerodict()
interarrival = zerodict()
parents = zerodict()
dirsadded = zerodict()
tzoffset = zerodict()
# If a mercurial repo is available, also model the commit history.
if repo:
revs = scmutil.revrange(repo, revs)
revs.sort()
progress = ui.makeprogress(_('analyzing'), unit=_('changesets'),
total=len(revs))
for i, rev in enumerate(revs):
progress.update(i)
ctx = repo[rev]
pl = ctx.parents()
pctx = pl[0]
prev = pctx.rev()
children[prev] += 1
p1distance[rev - prev] += 1
parents[len(pl)] += 1
tzoffset[ctx.date()[1]] += 1
if len(pl) > 1:
p2distance[rev - pl[1].rev()] += 1
if prev == rev - 1:
lastctx = pctx
else:
lastctx = repo[rev - 1]
if lastctx.rev() != nullrev:
timedelta = ctx.date()[0] - lastctx.date()[0]
interarrival[roundto(timedelta, 300)] += 1
diffopts = diffutil.diffallopts(ui, {'git': True})
diff = sum((d.splitlines()
for d in ctx.diff(pctx, opts=diffopts)), [])
fileadds, diradds, fileremoves, filechanges = 0, 0, 0, 0
for filename, mar, lineadd, lineremove, isbin in parsegitdiff(diff):
if isbin:
continue
added = sum(lineadd.itervalues(), 0)
if mar == 'm':
if added and lineremove:
lineschanged[roundto(added, 5),
roundto(lineremove, 5)] += 1
filechanges += 1
elif mar == 'a':
fileadds += 1
if '/' in filename:
filedir = filename.rsplit('/', 1)[0]
if filedir not in pctx.dirs():
diradds += 1
linesinfilesadded[roundto(added, 5)] += 1
elif mar == 'r':
fileremoves += 1
for length, count in lineadd.iteritems():
linelengths[length] += count
fileschanged[filechanges] += 1
filesadded[fileadds] += 1
dirsadded[diradds] += 1
filesremoved[fileremoves] += 1
progress.complete()
invchildren = zerodict()
for rev, count in children.iteritems():
invchildren[count] += 1
if output != '-':
ui.status(_('writing output to %s\n') % output)
def pronk(d):
return sorted(d.iteritems(), key=lambda x: x[1], reverse=True)
json.dump({'revs': len(revs),
'initdirs': pronk(dirs),
'lineschanged': pronk(lineschanged),
'children': pronk(invchildren),
'fileschanged': pronk(fileschanged),
'filesadded': pronk(filesadded),
'linesinfilesadded': pronk(linesinfilesadded),
'dirsadded': pronk(dirsadded),
'filesremoved': pronk(filesremoved),
'linelengths': pronk(linelengths),
'parents': pronk(parents),
'p1distance': pronk(p1distance),
'p2distance': pronk(p2distance),
'interarrival': pronk(interarrival),
'tzoffset': pronk(tzoffset),
},
fp)
fp.close()
@command('synthesize',
[('c', 'count', 0, _('create given number of commits'), _('COUNT')),
('', 'dict', '', _('path to a dictionary of words'), _('FILE')),
('', 'initfiles', 0, _('initial file count to create'), _('COUNT'))],
_('hg synthesize [OPTION].. DESCFILE'))
def synthesize(ui, repo, descpath, **opts):
'''synthesize commits based on a model of an existing repository
The model must have been generated by :hg:`analyze`. Commits will
be generated randomly according to the probabilities described in
the model. If --initfiles is set, the repository will be seeded with
the given number files following the modeled repository's directory
structure.
When synthesizing new content, commit descriptions, and user
names, words will be chosen randomly from a dictionary that is
presumed to contain one word per line. Use --dict to specify the
path to an alternate dictionary to use.
'''
try:
fp = hg.openpath(ui, descpath)
except Exception as err:
raise error.Abort('%s: %s' % (descpath, err[0].strerror))
desc = json.load(fp)
fp.close()
def cdf(l):
if not l:
return [], []
vals, probs = zip(*sorted(l, key=lambda x: x[1], reverse=True))
t = float(sum(probs, 0))
s, cdfs = 0, []
for v in probs:
s += v
cdfs.append(s / t)
return vals, cdfs
lineschanged = cdf(desc['lineschanged'])
fileschanged = cdf(desc['fileschanged'])
filesadded = cdf(desc['filesadded'])
dirsadded = cdf(desc['dirsadded'])
filesremoved = cdf(desc['filesremoved'])
linelengths = cdf(desc['linelengths'])
parents = cdf(desc['parents'])
p1distance = cdf(desc['p1distance'])
p2distance = cdf(desc['p2distance'])
interarrival = cdf(desc['interarrival'])
linesinfilesadded = cdf(desc['linesinfilesadded'])
tzoffset = cdf(desc['tzoffset'])
dictfile = opts.get('dict') or '/usr/share/dict/words'
try:
fp = open(dictfile, 'rU')
except IOError as err:
raise error.Abort('%s: %s' % (dictfile, err.strerror))
words = fp.read().splitlines()
fp.close()
initdirs = {}
if desc['initdirs']:
for k, v in desc['initdirs']:
initdirs[k.encode('utf-8').replace('.hg', '_hg')] = v
initdirs = renamedirs(initdirs, words)
initdirscdf = cdf(initdirs)
def pick(cdf):
return cdf[0][bisect.bisect_left(cdf[1], random.random())]
def pickpath():
return os.path.join(pick(initdirscdf), random.choice(words))
def makeline(minimum=0):
total = max(minimum, pick(linelengths))
c, l = 0, []
while c < total:
w = random.choice(words)
c += len(w) + 1
l.append(w)
return ' '.join(l)
wlock = repo.wlock()
lock = repo.lock()
nevertouch = {'.hgsub', '.hgignore', '.hgtags'}
_synthesizing = _('synthesizing')
_files = _('initial files')
_changesets = _('changesets')
# Synthesize a single initial revision adding files to the repo according
# to the modeled directory structure.
initcount = int(opts['initfiles'])
if initcount and initdirs:
pctx = repo['.']
dirs = set(pctx.dirs())
files = {}
def validpath(path):
# Don't pick filenames which are already directory names.
if path in dirs:
return False
# Don't pick directories which were used as file names.
while path:
if path in files:
return False
path = os.path.dirname(path)
return True
progress = ui.makeprogress(_synthesizing, unit=_files, total=initcount)
for i in xrange(0, initcount):
progress.update(i)
path = pickpath()
while not validpath(path):
path = pickpath()
data = '%s contents\n' % path
files[path] = data
dir = os.path.dirname(path)
while dir and dir not in dirs:
dirs.add(dir)
dir = os.path.dirname(dir)
def filectxfn(repo, memctx, path):
return context.memfilectx(repo, memctx, path, files[path])
progress.complete()
message = 'synthesized wide repo with %d files' % (len(files),)
mc = context.memctx(repo, [pctx.node(), nullid], message,
files, filectxfn, ui.username(),
'%d %d' % dateutil.makedate())
initnode = mc.commit()
if ui.debugflag:
hexfn = hex
else:
hexfn = short
ui.status(_('added commit %s with %d files\n')
% (hexfn(initnode), len(files)))
# Synthesize incremental revisions to the repository, adding repo depth.
count = int(opts['count'])
heads = set(map(repo.changelog.rev, repo.heads()))
progress = ui.makeprogress(_synthesizing, unit=_changesets, total=count)
for i in xrange(count):
progress.update(i)
node = repo.changelog.node
revs = len(repo)
def pickhead(heads, distance):
if heads:
lheads = sorted(heads)
rev = revs - min(pick(distance), revs)
if rev < lheads[-1]:
rev = lheads[bisect.bisect_left(lheads, rev)]
else:
rev = lheads[-1]
return rev, node(rev)
return nullrev, nullid
r1 = revs - min(pick(p1distance), revs)
p1 = node(r1)
# the number of heads will grow without bound if we use a pure
# model, so artificially constrain their proliferation
toomanyheads = len(heads) > random.randint(1, 20)
if p2distance[0] and (pick(parents) == 2 or toomanyheads):
r2, p2 = pickhead(heads.difference([r1]), p2distance)
else:
r2, p2 = nullrev, nullid
pl = [p1, p2]
pctx = repo[r1]
mf = pctx.manifest()
mfk = mf.keys()
changes = {}
if mfk:
for __ in xrange(pick(fileschanged)):
for __ in xrange(10):
fctx = pctx.filectx(random.choice(mfk))
path = fctx.path()
if not (path in nevertouch or fctx.isbinary() or
'l' in fctx.flags()):
break
lines = fctx.data().splitlines()
add, remove = pick(lineschanged)
for __ in xrange(remove):
if not lines:
break
del lines[random.randrange(0, len(lines))]
for __ in xrange(add):
lines.insert(random.randint(0, len(lines)), makeline())
path = fctx.path()
changes[path] = '\n'.join(lines) + '\n'
for __ in xrange(pick(filesremoved)):
for __ in xrange(10):
path = random.choice(mfk)
if path not in changes:
break
if filesadded:
dirs = list(pctx.dirs())
dirs.insert(0, '')
for __ in xrange(pick(filesadded)):
pathstr = ''
while pathstr in dirs:
path = [random.choice(dirs)]
if pick(dirsadded):
path.append(random.choice(words))
path.append(random.choice(words))
pathstr = '/'.join(filter(None, path))
data = '\n'.join(makeline()
for __ in xrange(pick(linesinfilesadded))) + '\n'
changes[pathstr] = data
def filectxfn(repo, memctx, path):
if path not in changes:
return None
return context.memfilectx(repo, memctx, path, changes[path])
if not changes:
continue
if revs:
date = repo['tip'].date()[0] + pick(interarrival)
else:
date = time.time() - (86400 * count)
# dates in mercurial must be positive, fit in 32-bit signed integers.
date = min(0x7fffffff, max(0, date))
user = random.choice(words) + '@' + random.choice(words)
mc = context.memctx(repo, pl, makeline(minimum=2),
sorted(changes),
filectxfn, user, '%d %d' % (date, pick(tzoffset)))
newnode = mc.commit()
heads.add(repo.changelog.rev(newnode))
heads.discard(r1)
heads.discard(r2)
progress.complete()
lock.release()
wlock.release()
def renamedirs(dirs, words):
'''Randomly rename the directory names in the per-dir file count dict.'''
wordgen = itertools.cycle(words)
replacements = {'': ''}
def rename(dirpath):
'''Recursively rename the directory and all path prefixes.
The mapping from path to renamed path is stored for all path prefixes
as in dynamic programming, ensuring linear runtime and consistent
renaming regardless of iteration order through the model.
'''
if dirpath in replacements:
return replacements[dirpath]
head, _ = os.path.split(dirpath)
if head:
head = rename(head)
else:
head = ''
renamed = os.path.join(head, next(wordgen))
replacements[dirpath] = renamed
return renamed
result = []
for dirpath, count in dirs.iteritems():
result.append([rename(dirpath.lstrip(os.sep)), count])
return result