Mercurial > hg
view tests/drawdag.py @ 37048:fc5e261915b9
wireproto: require POST for all HTTPv2 requests
Wire protocol version 1 transfers argument data via request
headers by default. This has historically caused problems because
servers institute limits on the length of individual HTTP headers
as well as the total size of all request headers. Mercurial servers
can advertise the maximum length of an individual header. But
there's no guarantee any intermediate HTTP agents will accept
headers up to that length.
In the existing wire protocol, server operators typically also
key off the HTTP request method to implement authentication.
For example, GET requests translate to read-only requests and
can be allowed. But read-write commands must use POST and require
authentication. This has typically worked because the only wire
protocol commands that use POST modify the repo (e.g. the
"unbundle" command).
There is an experimental feature to enable clients to transmit
argument data via POST request bodies. This is technically a
better and more robust solution. But we can't enable it by default
because of servers assuming POST means write access.
In version 2 of the wire protocol, the permissions of a request
are encoded in the URL. And with it being a new protocol in a new
URL space, we're not constrained by backwards compatibility
requirements.
This commit adopts the technically superior mechanism of using
HTTP request bodies to send argument data by requiring POST for
all commands. Strictly speaking, it may be possible to send
request bodies on GET requests. But my experience is that not all
HTTP stacks support this. POST pretty much always works. Using POST
for read-only operations does sacrifice some RESTful design
purity. But this API cares about practicality, not about being
in Roy T. Fielding's REST ivory tower.
There's a chance we may relax this restriction in the future. But
for now, I want to see how far we can get with a POST only API.
Differential Revision: https://phab.mercurial-scm.org/D2837
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Tue, 13 Mar 2018 11:57:43 -0700 |
parents | 4e41b59633fa |
children | 9a813e4c8406 |
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# drawdag.py - convert ASCII revision DAG to actual changesets # # Copyright 2016 Facebook, Inc. # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. """ create changesets from an ASCII graph for testing purpose. For example, given the following input:: c d |/ b | a 4 changesets and 4 local tags will be created. `hg log -G -T "{rev} {desc} (tag: {tags})"` will output:: o 3 d (tag: d tip) | | o 2 c (tag: c) |/ o 1 b (tag: b) | o 0 a (tag: a) For root nodes (nodes without parents) in the graph, they can be revsets pointing to existing nodes. The ASCII graph could also have disconnected components with same names referring to the same changeset. Therefore, given the repo having the 4 changesets (and tags) above, with the following ASCII graph as input:: foo bar bar foo | / | | ancestor(c,d) a baz The result (`hg log -G -T "{desc}"`) will look like:: o foo |\ +---o bar | | | | o | baz | / +---o d | | +---o c | | o | b |/ o a Note that if you take the above `hg log` output directly as input. It will work as expected - the result would be an isomorphic graph:: o foo |\ | | o d | |/ | | o c | |/ | | o bar | |/| | o | b | |/ o / baz / o a This is because 'o' is specially handled in the input: instead of using 'o' as the node name, the word to the right will be used. Some special comments could have side effects: - Create obsmarkers # replace: A -> B -> C -> D # chained 1 to 1 replacements # split: A -> B, C # 1 to many # prune: A, B, C # many to nothing """ from __future__ import absolute_import, print_function import collections import itertools import re from mercurial.i18n import _ from mercurial import ( context, error, node, obsolete, pycompat, registrar, scmutil, tags as tagsmod, ) cmdtable = {} command = registrar.command(cmdtable) _pipechars = b'\\/+-|' _nonpipechars = b''.join(pycompat.bytechr(i) for i in range(33, 127) if pycompat.bytechr(i) not in _pipechars) def _isname(ch): """char -> bool. return True if ch looks like part of a name, False otherwise""" return ch in _nonpipechars def _parseasciigraph(text): r"""str -> {str : [str]}. convert the ASCII graph to edges >>> import pprint >>> pprint.pprint({pycompat.sysstr(k): [pycompat.sysstr(vv) for vv in v] ... for k, v in _parseasciigraph(br''' ... G ... | ... I D C F # split: B -> E, F, G ... \ \| | # replace: C -> D -> H ... H B E # prune: F, I ... \|/ ... A ... ''').items()}) {'A': [], 'B': ['A'], 'C': ['B'], 'D': ['B'], 'E': ['A'], 'F': ['E'], 'G': ['F'], 'H': ['A'], 'I': ['H']} >>> pprint.pprint({pycompat.sysstr(k): [pycompat.sysstr(vv) for vv in v] ... for k, v in _parseasciigraph(br''' ... o foo ... |\ ... +---o bar ... | | | ... | o | baz ... | / ... +---o d ... | | ... +---o c ... | | ... o | b ... |/ ... o a ... ''').items()}) {'a': [], 'b': ['a'], 'bar': ['b', 'a'], 'baz': [], 'c': ['b'], 'd': ['b'], 'foo': ['baz', 'b']} """ lines = text.splitlines() edges = collections.defaultdict(list) # {node: []} def get(y, x): """(int, int) -> char. give a coordinate, return the char. return a space for anything out of range""" if x < 0 or y < 0: return b' ' try: return lines[y][x:x + 1] or b' ' except IndexError: return b' ' def getname(y, x): """(int, int) -> str. like get(y, x) but concatenate left and right parts. if name is an 'o', try to replace it to the right""" result = b'' for i in itertools.count(0): ch = get(y, x - i) if not _isname(ch): break result = ch + result for i in itertools.count(1): ch = get(y, x + i) if not _isname(ch): break result += ch if result == b'o': # special handling, find the name to the right result = b'' for i in itertools.count(2): ch = get(y, x + i) if ch == b' ' or ch in _pipechars: if result or x + i >= len(lines[y]): break else: result += ch return result or b'o' return result def parents(y, x): """(int, int) -> [str]. follow the ASCII edges at given position, return a list of parents""" visited = {(y, x)} visit = [] result = [] def follow(y, x, expected): """conditionally append (y, x) to visit array, if it's a char in excepted. 'o' in expected means an '_isname' test. if '-' (or '+') is not in excepted, and get(y, x) is '-' (or '+'), the next line (y + 1, x) will be checked instead.""" ch = get(y, x) if any(ch == c and c not in expected for c in (b'-', b'+')): y += 1 return follow(y + 1, x, expected) if ch in expected or (b'o' in expected and _isname(ch)): visit.append((y, x)) # -o- # starting point: # /|\ # follow '-' (horizontally), and '/|\' (to the bottom) follow(y + 1, x, b'|') follow(y + 1, x - 1, b'/') follow(y + 1, x + 1, b'\\') follow(y, x - 1, b'-') follow(y, x + 1, b'-') while visit: y, x = visit.pop() if (y, x) in visited: continue visited.add((y, x)) ch = get(y, x) if _isname(ch): result.append(getname(y, x)) continue elif ch == b'|': follow(y + 1, x, b'/|o') follow(y + 1, x - 1, b'/') follow(y + 1, x + 1, b'\\') elif ch == b'+': follow(y, x - 1, b'-') follow(y, x + 1, b'-') follow(y + 1, x - 1, b'/') follow(y + 1, x + 1, b'\\') follow(y + 1, x, b'|') elif ch == b'\\': follow(y + 1, x + 1, b'\\|o') elif ch == b'/': follow(y + 1, x - 1, b'/|o') elif ch == b'-': follow(y, x - 1, b'-+o') follow(y, x + 1, b'-+o') return result for y, line in enumerate(lines): for x, ch in enumerate(pycompat.bytestr(line)): if ch == b'#': # comment break if _isname(ch): edges[getname(y, x)] += parents(y, x) return dict(edges) class simplefilectx(object): def __init__(self, path, data): self._data = data self._path = path def data(self): return self._data def filenode(self): return None def path(self): return self._path def renamed(self): return None def flags(self): return b'' class simplecommitctx(context.committablectx): def __init__(self, repo, name, parentctxs, added): opts = { 'changes': scmutil.status([], list(added), [], [], [], [], []), 'date': b'0 0', 'extra': {b'branch': b'default'}, } super(simplecommitctx, self).__init__(self, name, **opts) self._repo = repo self._added = added self._parents = parentctxs while len(self._parents) < 2: self._parents.append(repo[node.nullid]) def filectx(self, key): return simplefilectx(key, self._added[key]) def commit(self): return self._repo.commitctx(self) def _walkgraph(edges): """yield node, parents in topologically order""" visible = set(edges.keys()) remaining = {} # {str: [str]} for k, vs in edges.items(): for v in vs: if v not in remaining: remaining[v] = [] remaining[k] = vs[:] while remaining: leafs = [k for k, v in remaining.items() if not v] if not leafs: raise error.Abort(_('the graph has cycles')) for leaf in sorted(leafs): if leaf in visible: yield leaf, edges[leaf] del remaining[leaf] for k, v in remaining.items(): if leaf in v: v.remove(leaf) def _getcomments(text): """ >>> [pycompat.sysstr(s) for s in _getcomments(br''' ... G ... | ... I D C F # split: B -> E, F, G ... \ \| | # replace: C -> D -> H ... H B E # prune: F, I ... \|/ ... A ... ''')] ['split: B -> E, F, G', 'replace: C -> D -> H', 'prune: F, I'] """ for line in text.splitlines(): if b' # ' not in line: continue yield line.split(b' # ', 1)[1].split(b' # ')[0].strip() @command(b'debugdrawdag', []) def debugdrawdag(ui, repo, **opts): """read an ASCII graph from stdin and create changesets The ASCII graph is like what :hg:`log -G` outputs, with each `o` replaced to the name of the node. The command will create dummy changesets and local tags with those names to make the dummy changesets easier to be referred to. If the name of a node is a single character 'o', It will be replaced by the word to the right. This makes it easier to reuse :hg:`log -G -T '{desc}'` outputs. For root (no parents) nodes, revset can be used to query existing repo. Note that the revset cannot have confusing characters which can be seen as the part of the graph edges, like `|/+-\`. """ text = ui.fin.read() # parse the graph and make sure len(parents) <= 2 for each node edges = _parseasciigraph(text) for k, v in edges.items(): if len(v) > 2: raise error.Abort(_('%s: too many parents: %s') % (k, b' '.join(v))) # parse comments to get extra file content instructions files = collections.defaultdict(dict) # {(name, path): content} comments = list(_getcomments(text)) filere = re.compile(br'^(\w+)/([\w/]+)\s*=\s*(.*)$', re.M) for name, path, content in filere.findall(b'\n'.join(comments)): content = content.replace(br'\n', b'\n').replace(br'\1', b'\1') files[name][path] = content committed = {None: node.nullid} # {name: node} # for leaf nodes, try to find existing nodes in repo for name, parents in edges.items(): if len(parents) == 0: try: committed[name] = scmutil.revsingle(repo, name) except error.RepoLookupError: pass # commit in topological order for name, parents in _walkgraph(edges): if name in committed: continue pctxs = [repo[committed[n]] for n in parents] pctxs.sort(key=lambda c: c.node()) added = {} if len(parents) > 1: # If it's a merge, take the files and contents from the parents for f in pctxs[1].manifest(): if f not in pctxs[0].manifest(): added[f] = pctxs[1][f].data() else: # If it's not a merge, add a single file added[name] = name # add extra file contents in comments for path, content in files.get(name, {}).items(): added[path] = content ctx = simplecommitctx(repo, name, pctxs, added) n = ctx.commit() committed[name] = n tagsmod.tag(repo, [name], n, message=None, user=None, date=None, local=True) # handle special comments with repo.wlock(), repo.lock(), repo.transaction(b'drawdag'): getctx = lambda x: repo.unfiltered()[committed[x.strip()]] for comment in comments: rels = [] # obsolete relationships args = comment.split(b':', 1) if len(args) <= 1: continue cmd = args[0].strip() arg = args[1].strip() if cmd in (b'replace', b'rebase', b'amend'): nodes = [getctx(m) for m in arg.split(b'->')] for i in range(len(nodes) - 1): rels.append((nodes[i], (nodes[i + 1],))) elif cmd in (b'split',): pre, succs = arg.split(b'->') succs = succs.split(b',') rels.append((getctx(pre), (getctx(s) for s in succs))) elif cmd in (b'prune',): for n in arg.split(b','): rels.append((getctx(n), ())) if rels: obsolete.createmarkers(repo, rels, date=(0, 0), operation=cmd)