comparison tests/test-wireproto-exchangev2.t @ 39638:d292328e0143

exchangev2: fetch manifest revisions

Now that the server has support for retrieving manifest data, we can
implement the client bits to call it.

We teach the changeset fetching code to capture the manifest revisions
that are encountered on incoming changesets. We then feed this into a
new function which filters out known manifests and then batches up
manifest data requests to the server.

This is different from the previous wire protocol in a few notable
ways.

First, the client fetches manifest data separately and explicitly.
Before, we'd ask the server for data pertaining to some changesets
(via a "getbundle" command) and manifests (and files) would be sent
automatically. Providing an API for looking up just manifest data
separately gives clients much more flexibility for manifest management.
For example, a client may choose to only fetch manifest data on demand
instead of prefetching it (i.e. partial clone).

Second, we send N commands to the server for manifest retrieval instead
of 1. This property has a few nice side-effects. One is that the
deterministic nature of the requests lends itself to server-side
caching. For example, say the remote has 50,000 manifests. If the
server is configured to cache responses, each time a new commit
arrives, you will have a cache miss and need to regenerate all outgoing
data. But if you makes N requests requesting 10,000 manifests each,
a new commit will still yield cache hits on the initial, unchanged
manifest batches/requests.

A derived benefit from these properties is that resumable clone is
conceptually simpler to implement. When making a monolithic request
for all of the repository data, recovering from an interrupted clone
is hard because the server was in the driver's seat and was maintaining
state about all the data that needed transferred. With the client
driving fetching, the client can persist the set of unfetched entities
and retry/resume a fetch if something goes wrong. Or we can fetch all
data N changesets at a time and slowly build up a repository. This
approach is drastically easier to implement when we have server APIs
exposing low-level repository primitives (such as manifests and files).

We don't yet support tree manifests. But it should be possible to
implement that with the existing wire protocol command.

Differential Revision: https://phab.mercurial-scm.org/D4489

39637:c7a7c7e844e5

  add changeset 4432d83626e8
  add changeset cd2534766bec
  add changeset e96ae20f4188
  add changeset caa2a465451d
  checking for updated bookmarks
  updating the branch cache
  new changesets 3390ef850073:caa2a465451d (3 drafts)

All changesets should have been transferred

  | o  1 4432d83626e8a98655f062ec1f2a43b07f7fbbb0 public
  |/
  o  0 3390ef850073fbc2f0dfff2244342c8e9229013a public
  

Cloning only a specific revision works

  $ hg --debug clone -U -r 4432d83626e8 http://localhost:$HGPORT client-singlehead
  using http://localhost:$HGPORT/
  sending capabilities command

  received frame(size=353; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  add changeset 3390ef850073
  add changeset 4432d83626e8
  checking for updated bookmarks
  updating the branch cache
  new changesets 3390ef850073:4432d83626e8

  $ cd client-singlehead

  $ hg log -G -T '{rev} {node} {phase}\n'
  o  1 4432d83626e8a98655f062ec1f2a43b07f7fbbb0 public
  |
  o  0 3390ef850073fbc2f0dfff2244342c8e9229013a public
  

Incremental pull works

  $ hg --debug pull
  pulling from http://localhost:$HGPORT/

  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  add changeset cd2534766bec
  add changeset e96ae20f4188
  add changeset caa2a465451d
  checking for updated bookmarks
  updating the branch cache
  new changesets cd2534766bec:caa2a465451d (3 drafts)
  (run 'hg update' to get a working copy)

  $ hg log -G -T '{rev} {node} {phase}\n'

  | o  1 4432d83626e8a98655f062ec1f2a43b07f7fbbb0 public
  |/
  o  0 3390ef850073fbc2f0dfff2244342c8e9229013a public
  

Phase-only update works

  $ hg -R ../server-simple phase --public -r caa2a465451dd
  $ hg --debug pull
  pulling from http://localhost:$HGPORT/

  add changeset e96ae20f4188
  add changeset caa2a465451d
  checking for updated bookmarks
  adding remote bookmark book-1
  adding remote bookmark book-2
  updating the branch cache
  new changesets 3390ef850073:caa2a465451d (1 drafts)

  $ hg -R client-bookmarks bookmarks
     book-1                    0:3390ef850073

39638:d292328e0143

  add changeset 4432d83626e8
  add changeset cd2534766bec
  add changeset e96ae20f4188
  add changeset caa2a465451d
  checking for updated bookmarks
  sending 1 commands
  sending command manifestdata: {
    'fields': set([
      'parents',
      'revision'
    ]),
    'nodes': [
      '\x99/Gy\x02\x9a=\xf8\xd0fm\x00\xbb\x92OicN&A',
      '\xa9\x88\xfbCX>\x87\x1d\x1e\xd5u\x0e\xe0t\xc6\xd8@\xbb\xbf\xc8',
      '\xec\x80NH\x8c \x88\xc25\t\x9a\x10 u\x13\xbe\xcd\xc3\xdd\xa5',
      '\x04\\\x7f9\'\xda\x13\xe7Z\xf8\xf0\xe4\xf0HI\xe4a\xa9x\x0f',
      '7\x9c\xb0\xc2\xe6d\\y\xdd\xc5\x9a\x1dG\'\xa9\xfb\x83\n\xeb&'
    ],
    'tree': ''
  }
  received frame(size=11; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=continuation)
  received frame(size=922; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  updating the branch cache
  new changesets 3390ef850073:caa2a465451d (3 drafts)

All changesets should have been transferred

  | o  1 4432d83626e8a98655f062ec1f2a43b07f7fbbb0 public
  |/
  o  0 3390ef850073fbc2f0dfff2244342c8e9229013a public
  

All manifests should have been transferred

  $ hg -R client-simple debugindex -m
     rev linkrev nodeid       p1           p2
       0       0 992f4779029a 000000000000 000000000000
       1       1 a988fb43583e 992f4779029a 000000000000
       2       2 ec804e488c20 a988fb43583e 000000000000
       3       3 045c7f3927da 992f4779029a 000000000000
       4       4 379cb0c2e664 045c7f3927da 000000000000

Cloning only a specific revision works

  $ hg --debug clone -U -r 4432d83626e8 http://localhost:$HGPORT client-singlehead
  using http://localhost:$HGPORT/
  sending capabilities command

  received frame(size=353; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  add changeset 3390ef850073
  add changeset 4432d83626e8
  checking for updated bookmarks
  sending 1 commands
  sending command manifestdata: {
    'fields': set([
      'parents',
      'revision'
    ]),
    'nodes': [
      '\x99/Gy\x02\x9a=\xf8\xd0fm\x00\xbb\x92OicN&A',
      '\xa9\x88\xfbCX>\x87\x1d\x1e\xd5u\x0e\xe0t\xc6\xd8@\xbb\xbf\xc8'
    ],
    'tree': ''
  }
  received frame(size=11; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=continuation)
  received frame(size=376; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  updating the branch cache
  new changesets 3390ef850073:4432d83626e8

  $ cd client-singlehead

  $ hg log -G -T '{rev} {node} {phase}\n'
  o  1 4432d83626e8a98655f062ec1f2a43b07f7fbbb0 public
  |
  o  0 3390ef850073fbc2f0dfff2244342c8e9229013a public
  

  $ hg debugindex -m
     rev linkrev nodeid       p1           p2
       0       0 992f4779029a 000000000000 000000000000
       1       1 a988fb43583e 992f4779029a 000000000000

Incremental pull works

  $ hg --debug pull
  pulling from http://localhost:$HGPORT/

  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  add changeset cd2534766bec
  add changeset e96ae20f4188
  add changeset caa2a465451d
  checking for updated bookmarks
  sending 1 commands
  sending command manifestdata: {
    'fields': set([
      'parents',
      'revision'
    ]),
    'nodes': [
      '\xec\x80NH\x8c \x88\xc25\t\x9a\x10 u\x13\xbe\xcd\xc3\xdd\xa5',
      '\x04\\\x7f9\'\xda\x13\xe7Z\xf8\xf0\xe4\xf0HI\xe4a\xa9x\x0f',
      '7\x9c\xb0\xc2\xe6d\\y\xdd\xc5\x9a\x1dG\'\xa9\xfb\x83\n\xeb&'
    ],
    'tree': ''
  }
  received frame(size=11; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=continuation)
  received frame(size=559; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  updating the branch cache
  new changesets cd2534766bec:caa2a465451d (3 drafts)
  (run 'hg update' to get a working copy)

  $ hg log -G -T '{rev} {node} {phase}\n'

  | o  1 4432d83626e8a98655f062ec1f2a43b07f7fbbb0 public
  |/
  o  0 3390ef850073fbc2f0dfff2244342c8e9229013a public
  

  $ hg debugindex -m
     rev linkrev nodeid       p1           p2
       0       0 992f4779029a 000000000000 000000000000
       1       1 a988fb43583e 992f4779029a 000000000000
       2       2 ec804e488c20 a988fb43583e 000000000000
       3       3 045c7f3927da 992f4779029a 000000000000
       4       4 379cb0c2e664 045c7f3927da 000000000000

Phase-only update works

  $ hg -R ../server-simple phase --public -r caa2a465451dd
  $ hg --debug pull
  pulling from http://localhost:$HGPORT/

  add changeset e96ae20f4188
  add changeset caa2a465451d
  checking for updated bookmarks
  adding remote bookmark book-1
  adding remote bookmark book-2
  sending 1 commands
  sending command manifestdata: {
    'fields': set([
      'parents',
      'revision'
    ]),
    'nodes': [
      '\x99/Gy\x02\x9a=\xf8\xd0fm\x00\xbb\x92OicN&A',
      '\xa9\x88\xfbCX>\x87\x1d\x1e\xd5u\x0e\xe0t\xc6\xd8@\xbb\xbf\xc8',
      '\xec\x80NH\x8c \x88\xc25\t\x9a\x10 u\x13\xbe\xcd\xc3\xdd\xa5',
      '\x04\\\x7f9\'\xda\x13\xe7Z\xf8\xf0\xe4\xf0HI\xe4a\xa9x\x0f',
      '7\x9c\xb0\xc2\xe6d\\y\xdd\xc5\x9a\x1dG\'\xa9\xfb\x83\n\xeb&'
    ],
    'tree': ''
  }
  received frame(size=11; request=1; stream=2; streamflags=stream-begin; type=command-response; flags=continuation)
  received frame(size=922; request=1; stream=2; streamflags=; type=command-response; flags=continuation)
  received frame(size=0; request=1; stream=2; streamflags=; type=command-response; flags=eos)
  updating the branch cache
  new changesets 3390ef850073:caa2a465451d (1 drafts)

  $ hg -R client-bookmarks bookmarks
     book-1                    0:3390ef850073