view tests/test-clonebundles.t @ 37047:fddcb51b5084

wireproto: define permissions-based routing of HTTPv2 wire protocol

Now that we have a scaffolding for serving version 2 of the HTTP
protocol, let's start implementing it.

A good place to start is URL routing and basic request processing
semantics. We can focus on content types, capabilities detect, etc
later.

Version 2 of the HTTP wire protocol encodes the needed permissions
of the request in the URL path. The reasons for this are documented
in the added documentation. In short, a) it makes it really easy and
fail proof for server administrators to implement path-based
authentication and b) it will enable clients to realize very early in
a server exchange that authentication will be required to complete
the operation. This latter point avoids all kinds of complexity and
problems, like dealing with Expect: 100-continue and clients finding
out later during `hg push` that they need to provide authentication.
This will avoid the current badness where clients send a full bundle,
get an HTTP 403, provide authentication, then retransmit the bundle.

In order to implement command checking, we needed to implement a
protocol handler for the new wire protocol. Our handler is just
small enough to run the code we've implemented.

Tests for the defined functionality have been added.

I very much want to refactor the permissions checking code and define
a better response format. But this can be done later. Nothing is
covered by backwards compatibility at this point.

Differential Revision: https://phab.mercurial-scm.org/D2836

Set up a server

  $ cat >> $HGRCPATH << EOF
  > [format]
  > usegeneraldelta=yes
  > EOF
  $ hg init server
  $ cd server
  $ cat >> .hg/hgrc << EOF
  > [extensions]
  > clonebundles =
  > EOF

  $ touch foo
  $ hg -q commit -A -m 'add foo'
  $ touch bar
  $ hg -q commit -A -m 'add bar'

  $ hg serve -d -p $HGPORT --pid-file hg.pid --accesslog access.log
  $ cat hg.pid >> $DAEMON_PIDS
  $ cd ..

Missing manifest should not result in server lookup

  $ hg --verbose clone -U http://localhost:$HGPORT no-manifest
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  new changesets 53245c60e682:aaff8d2ffbbf

  $ cat server/access.log
  * - - [*] "GET /?cmd=capabilities HTTP/1.1" 200 - (glob)
  $LOCALIP - - [$LOGDATE$] "GET /?cmd=batch HTTP/1.1" 200 - x-hgarg-1:cmds=heads+%3Bknown+nodes%3D x-hgproto-1:0.1 0.2 comp=$USUAL_COMPRESSIONS$ (glob)
  $LOCALIP - - [$LOGDATE$] "GET /?cmd=getbundle HTTP/1.1" 200 - x-hgarg-1:bookmarks=1&$USUAL_BUNDLE_CAPS$&cg=1&common=0000000000000000000000000000000000000000&heads=aaff8d2ffbbf07a46dd1f05d8ae7877e3f56e2a2&listkeys=bookmarks&phases=1 x-hgproto-1:0.1 0.2 comp=$USUAL_COMPRESSIONS$ (glob)

Empty manifest file results in retrieval
(the extension only checks if the manifest file exists)

  $ touch server/.hg/clonebundles.manifest
  $ hg --verbose clone -U http://localhost:$HGPORT empty-manifest
  no clone bundles available on remote; falling back to regular clone
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  new changesets 53245c60e682:aaff8d2ffbbf

Manifest file with invalid URL aborts

  $ echo 'http://does.not.exist/bundle.hg' > server/.hg/clonebundles.manifest
  $ hg clone http://localhost:$HGPORT 404-url
  applying clone bundle from http://does.not.exist/bundle.hg
  error fetching bundle: (.* not known|(\[Errno -?\d+])? No address associated with hostname) (re) (no-windows !)
  error fetching bundle: [Errno 11004] getaddrinfo failed (windows !)
  abort: error applying bundle
  (if this error persists, consider contacting the server operator or disable clone bundles via "--config ui.clonebundles=false")
  [255]

Server is not running aborts

  $ echo "http://localhost:$HGPORT1/bundle.hg" > server/.hg/clonebundles.manifest
  $ hg clone http://localhost:$HGPORT server-not-runner
  applying clone bundle from http://localhost:$HGPORT1/bundle.hg
  error fetching bundle: (.* refused.*|Protocol not supported|(.* )?Cannot assign requested address) (re)
  abort: error applying bundle
  (if this error persists, consider contacting the server operator or disable clone bundles via "--config ui.clonebundles=false")
  [255]

Server returns 404

  $ "$PYTHON" $TESTDIR/dumbhttp.py -p $HGPORT1 --pid http.pid
  $ cat http.pid >> $DAEMON_PIDS
  $ hg clone http://localhost:$HGPORT running-404
  applying clone bundle from http://localhost:$HGPORT1/bundle.hg
  HTTP error fetching bundle: HTTP Error 404: File not found
  abort: error applying bundle
  (if this error persists, consider contacting the server operator or disable clone bundles via "--config ui.clonebundles=false")
  [255]

We can override failure to fall back to regular clone

  $ hg --config ui.clonebundlefallback=true clone -U http://localhost:$HGPORT 404-fallback
  applying clone bundle from http://localhost:$HGPORT1/bundle.hg
  HTTP error fetching bundle: HTTP Error 404: File not found
  falling back to normal clone
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  new changesets 53245c60e682:aaff8d2ffbbf

Bundle with partial content works

  $ hg -R server bundle --type gzip-v1 --base null -r 53245c60e682 partial.hg
  1 changesets found

We verify exact bundle content as an extra check against accidental future
changes. If this output changes, we could break old clients.

  $ f --size --hexdump partial.hg
  partial.hg: size=207
  0000: 48 47 31 30 47 5a 78 9c 63 60 60 98 17 ac 12 93 |HG10GZx.c``.....|
  0010: f0 ac a9 23 45 70 cb bf 0d 5f 59 4e 4a 7f 79 21 |...#Ep..._YNJ.y!|
  0020: 9b cc 40 24 20 a0 d7 ce 2c d1 38 25 cd 24 25 d5 |..@$ ...,.8%.$%.|
  0030: d8 c2 22 cd 38 d9 24 cd 22 d5 c8 22 cd 24 cd 32 |..".8.$."..".$.2|
  0040: d1 c2 d0 c4 c8 d2 32 d1 38 39 29 c9 34 cd d4 80 |......2.89).4...|
  0050: ab 24 b5 b8 84 cb 40 c1 80 2b 2d 3f 9f 8b 2b 31 |.$....@..+-?..+1|
  0060: 25 45 01 c8 80 9a d2 9b 65 fb e5 9e 45 bf 8d 7f |%E......e...E...|
  0070: 9f c6 97 9f 2b 44 34 67 d9 ec 8e 0f a0 92 0b 75 |....+D4g.......u|
  0080: 41 d6 24 59 18 a4 a4 9a a6 18 1a 5b 98 9b 5a 98 |A.$Y.......[..Z.|
  0090: 9a 18 26 9b a6 19 98 1a 99 99 26 a6 18 9a 98 24 |..&.......&....$|
  00a0: 26 59 a6 25 5a 98 a5 18 a6 24 71 41 35 b1 43 dc |&Y.%Z....$qA5.C.|
  00b0: 16 b2 83 f7 e9 45 8b d2 56 c7 a3 1f 82 52 d7 8a |.....E..V....R..|
  00c0: 78 ed fc d5 76 f1 36 35 dc 05 00 36 ed 5e c7    |x...v.65...6.^.|

  $ echo "http://localhost:$HGPORT1/partial.hg" > server/.hg/clonebundles.manifest
  $ hg clone -U http://localhost:$HGPORT partial-bundle
  applying clone bundle from http://localhost:$HGPORT1/partial.hg
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  finished applying clone bundle
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets aaff8d2ffbbf

Incremental pull doesn't fetch bundle

  $ hg clone -r 53245c60e682 -U http://localhost:$HGPORT partial-clone
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets 53245c60e682

  $ cd partial-clone
  $ hg pull
  pulling from http://localhost:$HGPORT/
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 1 changes to 1 files
  new changesets aaff8d2ffbbf
  (run 'hg update' to get a working copy)
  $ cd ..

Bundle with full content works

  $ hg -R server bundle --type gzip-v2 --base null -r tip full.hg
  2 changesets found

Again, we perform an extra check against bundle content changes. If this content
changes, clone bundles produced by new Mercurial versions may not be readable
by old clients.

  $ f --size --hexdump full.hg
  full.hg: size=442
  0000: 48 47 32 30 00 00 00 0e 43 6f 6d 70 72 65 73 73 |HG20....Compress|
  0010: 69 6f 6e 3d 47 5a 78 9c 63 60 60 d0 e4 76 f6 70 |ion=GZx.c``..v.p|
  0020: f4 73 77 75 0f f2 0f 0d 60 00 02 46 46 76 26 4e |.swu....`..FFv&N|
  0030: c6 b2 d4 a2 e2 cc fc 3c 03 a3 bc a4 e4 8c c4 bc |.......<........|
  0040: f4 d4 62 23 06 06 e6 19 40 f9 4d c1 2a 31 09 cf |..b#....@.M.*1..|
  0050: 9a 3a 52 04 b7 fc db f0 95 e5 a4 f4 97 17 b2 c9 |.:R.............|
  0060: 0c 14 00 02 e6 d9 99 25 1a a7 a4 99 a4 a4 1a 5b |.......%.......[|
  0070: 58 a4 19 27 9b a4 59 a4 1a 59 a4 99 a4 59 26 5a |X..'..Y..Y...Y&Z|
  0080: 18 9a 18 59 5a 26 1a 27 27 25 99 a6 99 1a 70 95 |...YZ&.''%....p.|
  0090: a4 16 97 70 19 28 18 70 a5 e5 e7 73 71 25 a6 a4 |...p.(.p...sq%..|
  00a0: 28 00 19 20 17 af fa df ab ff 7b 3f fb 92 dc 8b |(.. ......{?....|
  00b0: 1f 62 bb 9e b7 d7 d9 87 3d 5a 44 89 2f b0 99 87 |.b......=ZD./...|
  00c0: ec e2 54 63 43 e3 b4 64 43 73 23 33 43 53 0b 63 |..TcC..dCs#3CS.c|
  00d0: d3 14 23 03 a0 fb 2c 2c 0c d3 80 1e 30 49 49 b1 |..#...,,....0II.|
  00e0: 4c 4a 32 48 33 30 b0 34 42 b8 38 29 b1 08 e2 62 |LJ2H30.4B.8)...b|
  00f0: 20 03 6a ca c2 2c db 2f f7 2c fa 6d fc fb 34 be | .j..,./.,.m..4.|
  0100: fc 5c 21 a2 39 cb 66 77 7c 00 0d c3 59 17 14 58 |.\!.9.fw|...Y..X|
  0110: 49 16 06 29 a9 a6 29 86 c6 16 e6 a6 16 a6 26 86 |I..)..).......&.|
  0120: c9 a6 69 06 a6 46 66 a6 89 29 86 26 26 89 49 96 |..i..Ff..).&&.I.|
  0130: 69 89 16 66 29 86 29 49 5c 20 07 3e 16 fe 23 ae |i..f).)I\ .>..#.|
  0140: 26 da 1c ab 10 1f d1 f8 e3 b3 ef cd dd fc 0c 93 |&...............|
  0150: 88 75 34 36 75 04 82 55 17 14 36 a4 38 10 04 d8 |.u46u..U..6.8...|
  0160: 21 01 9a b1 83 f7 e9 45 8b d2 56 c7 a3 1f 82 52 |!......E..V....R|
  0170: d7 8a 78 ed fc d5 76 f1 36 25 81 89 c7 ad ec 90 |..x...v.6%......|
  0180: 54 47 75 2b 89 48 b1 b2 62 ce 8e ce 1e ae 56 41 |TGu+.H..b.....VA|
  0190: ae 61 ba 4e 41 8e 7e ce 1e ba 60 01 a0 14 23 58 |.a.NA.~...`...#X|
  01a0: 81 35 c8 7d 40 cc 04 e2 a4 a4 a6 25 96 e6 94 60 |.5.}@......%...`|
  01b0: 33 17 5f 54 00 00 01 1b 0a ec                   |3._T......|

  $ echo "http://localhost:$HGPORT1/full.hg" > server/.hg/clonebundles.manifest
  $ hg clone -U http://localhost:$HGPORT full-bundle
  applying clone bundle from http://localhost:$HGPORT1/full.hg
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  finished applying clone bundle
  searching for changes
  no changes found

Feature works over SSH

  $ hg clone -U -e "\"$PYTHON\" \"$TESTDIR/dummyssh\"" ssh://user@dummy/server ssh-full-clone
  applying clone bundle from http://localhost:$HGPORT1/full.hg
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  finished applying clone bundle
  searching for changes
  no changes found

Entry with unknown BUNDLESPEC is filtered and not used

  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://bad.entry1 BUNDLESPEC=UNKNOWN
  > http://bad.entry2 BUNDLESPEC=xz-v1
  > http://bad.entry3 BUNDLESPEC=none-v100
  > http://localhost:$HGPORT1/full.hg BUNDLESPEC=gzip-v2
  > EOF

  $ hg clone -U http://localhost:$HGPORT filter-unknown-type
  applying clone bundle from http://localhost:$HGPORT1/full.hg
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  finished applying clone bundle
  searching for changes
  no changes found

Automatic fallback when all entries are filtered

  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://bad.entry BUNDLESPEC=UNKNOWN
  > EOF

  $ hg clone -U http://localhost:$HGPORT filter-all
  no compatible clone bundles available on server; falling back to regular clone
  (you may want to report this to the server operator)
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  new changesets 53245c60e682:aaff8d2ffbbf

URLs requiring SNI are filtered in Python <2.7.9

  $ cp full.hg sni.hg
  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://localhost:$HGPORT1/sni.hg REQUIRESNI=true
  > http://localhost:$HGPORT1/full.hg
  > EOF

#if sslcontext
Python 2.7.9+ support SNI

  $ hg clone -U http://localhost:$HGPORT sni-supported
  applying clone bundle from http://localhost:$HGPORT1/sni.hg
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  finished applying clone bundle
  searching for changes
  no changes found
#else
Python <2.7.9 will filter SNI URLs

  $ hg clone -U http://localhost:$HGPORT sni-unsupported
  applying clone bundle from http://localhost:$HGPORT1/full.hg
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  finished applying clone bundle
  searching for changes
  no changes found
#endif

Stream clone bundles are supported

  $ hg -R server debugcreatestreamclonebundle packed.hg
  writing 613 bytes for 4 files
  bundle requirements: generaldelta, revlogv1

No bundle spec should work

  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://localhost:$HGPORT1/packed.hg
  > EOF

  $ hg clone -U http://localhost:$HGPORT stream-clone-no-spec
  applying clone bundle from http://localhost:$HGPORT1/packed.hg
  4 files to transfer, 613 bytes of data
  transferred 613 bytes in *.* seconds (*) (glob)
  finished applying clone bundle
  searching for changes
  no changes found

Bundle spec without parameters should work

  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://localhost:$HGPORT1/packed.hg BUNDLESPEC=none-packed1
  > EOF

  $ hg clone -U http://localhost:$HGPORT stream-clone-vanilla-spec
  applying clone bundle from http://localhost:$HGPORT1/packed.hg
  4 files to transfer, 613 bytes of data
  transferred 613 bytes in *.* seconds (*) (glob)
  finished applying clone bundle
  searching for changes
  no changes found

Bundle spec with format requirements should work

  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://localhost:$HGPORT1/packed.hg BUNDLESPEC=none-packed1;requirements%3Drevlogv1
  > EOF

  $ hg clone -U http://localhost:$HGPORT stream-clone-supported-requirements
  applying clone bundle from http://localhost:$HGPORT1/packed.hg
  4 files to transfer, 613 bytes of data
  transferred 613 bytes in *.* seconds (*) (glob)
  finished applying clone bundle
  searching for changes
  no changes found

Stream bundle spec with unknown requirements should be filtered out

  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://localhost:$HGPORT1/packed.hg BUNDLESPEC=none-packed1;requirements%3Drevlogv42
  > EOF

  $ hg clone -U http://localhost:$HGPORT stream-clone-unsupported-requirements
  no compatible clone bundles available on server; falling back to regular clone
  (you may want to report this to the server operator)
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  new changesets 53245c60e682:aaff8d2ffbbf

Set up manifest for testing preferences
(Remember, the TYPE does not have to match reality - the URL is
important)

  $ cp full.hg gz-a.hg
  $ cp full.hg gz-b.hg
  $ cp full.hg bz2-a.hg
  $ cp full.hg bz2-b.hg
  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://localhost:$HGPORT1/gz-a.hg BUNDLESPEC=gzip-v2 extra=a
  > http://localhost:$HGPORT1/bz2-a.hg BUNDLESPEC=bzip2-v2 extra=a
  > http://localhost:$HGPORT1/gz-b.hg BUNDLESPEC=gzip-v2 extra=b
  > http://localhost:$HGPORT1/bz2-b.hg BUNDLESPEC=bzip2-v2 extra=b
  > EOF

Preferring an undefined attribute will take first entry

  $ hg --config ui.clonebundleprefers=foo=bar clone -U http://localhost:$HGPORT prefer-foo
  applying clone bundle from http://localhost:$HGPORT1/gz-a.hg
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  finished applying clone bundle
  searching for changes
  no changes found

Preferring bz2 type will download first entry of that type

  $ hg --config ui.clonebundleprefers=COMPRESSION=bzip2 clone -U http://localhost:$HGPORT prefer-bz
  applying clone bundle from http://localhost:$HGPORT1/bz2-a.hg
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  finished applying clone bundle
  searching for changes
  no changes found

Preferring multiple values of an option works

  $ hg --config ui.clonebundleprefers=COMPRESSION=unknown,COMPRESSION=bzip2 clone -U http://localhost:$HGPORT prefer-multiple-bz
  applying clone bundle from http://localhost:$HGPORT1/bz2-a.hg
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  finished applying clone bundle
  searching for changes
  no changes found

Sorting multiple values should get us back to original first entry

  $ hg --config ui.clonebundleprefers=BUNDLESPEC=unknown,BUNDLESPEC=gzip-v2,BUNDLESPEC=bzip2-v2 clone -U http://localhost:$HGPORT prefer-multiple-gz
  applying clone bundle from http://localhost:$HGPORT1/gz-a.hg
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  finished applying clone bundle
  searching for changes
  no changes found

Preferring multiple attributes has correct order

  $ hg --config ui.clonebundleprefers=extra=b,BUNDLESPEC=bzip2-v2 clone -U http://localhost:$HGPORT prefer-separate-attributes
  applying clone bundle from http://localhost:$HGPORT1/bz2-b.hg
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  finished applying clone bundle
  searching for changes
  no changes found

Test where attribute is missing from some entries

  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://localhost:$HGPORT1/gz-a.hg BUNDLESPEC=gzip-v2
  > http://localhost:$HGPORT1/bz2-a.hg BUNDLESPEC=bzip2-v2
  > http://localhost:$HGPORT1/gz-b.hg BUNDLESPEC=gzip-v2 extra=b
  > http://localhost:$HGPORT1/bz2-b.hg BUNDLESPEC=bzip2-v2 extra=b
  > EOF

  $ hg --config ui.clonebundleprefers=extra=b clone -U http://localhost:$HGPORT prefer-partially-defined-attribute
  applying clone bundle from http://localhost:$HGPORT1/gz-b.hg
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  finished applying clone bundle
  searching for changes
  no changes found

Test interaction between clone bundles and --stream

A manifest with just a gzip bundle

  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://localhost:$HGPORT1/gz-a.hg BUNDLESPEC=gzip-v2
  > EOF

  $ hg clone -U --stream http://localhost:$HGPORT uncompressed-gzip
  no compatible clone bundles available on server; falling back to regular clone
  (you may want to report this to the server operator)
  streaming all changes
  4 files to transfer, 613 bytes of data
  transferred 613 bytes in * seconds (*) (glob)
  searching for changes
  no changes found

A manifest with a stream clone but no BUNDLESPEC

  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://localhost:$HGPORT1/packed.hg
  > EOF

  $ hg clone -U --stream http://localhost:$HGPORT uncompressed-no-bundlespec
  no compatible clone bundles available on server; falling back to regular clone
  (you may want to report this to the server operator)
  streaming all changes
  4 files to transfer, 613 bytes of data
  transferred 613 bytes in * seconds (*) (glob)
  searching for changes
  no changes found

A manifest with a gzip bundle and a stream clone

  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://localhost:$HGPORT1/gz-a.hg BUNDLESPEC=gzip-v2
  > http://localhost:$HGPORT1/packed.hg BUNDLESPEC=none-packed1
  > EOF

  $ hg clone -U --stream http://localhost:$HGPORT uncompressed-gzip-packed
  applying clone bundle from http://localhost:$HGPORT1/packed.hg
  4 files to transfer, 613 bytes of data
  transferred 613 bytes in * seconds (*) (glob)
  finished applying clone bundle
  searching for changes
  no changes found

A manifest with a gzip bundle and stream clone with supported requirements

  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://localhost:$HGPORT1/gz-a.hg BUNDLESPEC=gzip-v2
  > http://localhost:$HGPORT1/packed.hg BUNDLESPEC=none-packed1;requirements%3Drevlogv1
  > EOF

  $ hg clone -U --stream http://localhost:$HGPORT uncompressed-gzip-packed-requirements
  applying clone bundle from http://localhost:$HGPORT1/packed.hg
  4 files to transfer, 613 bytes of data
  transferred 613 bytes in * seconds (*) (glob)
  finished applying clone bundle
  searching for changes
  no changes found

A manifest with a gzip bundle and a stream clone with unsupported requirements

  $ cat > server/.hg/clonebundles.manifest << EOF
  > http://localhost:$HGPORT1/gz-a.hg BUNDLESPEC=gzip-v2
  > http://localhost:$HGPORT1/packed.hg BUNDLESPEC=none-packed1;requirements%3Drevlogv42
  > EOF

  $ hg clone -U --stream http://localhost:$HGPORT uncompressed-gzip-packed-unsupported-requirements
  no compatible clone bundles available on server; falling back to regular clone
  (you may want to report this to the server operator)
  streaming all changes
  4 files to transfer, 613 bytes of data
  transferred 613 bytes in * seconds (*) (glob)
  searching for changes
  no changes found

Test clone bundle retrieved through bundle2

  $ cat << EOF >> $HGRCPATH
  > [extensions]
  > largefiles=
  > EOF
  $ killdaemons.py
  $ hg -R server serve -d -p $HGPORT --pid-file hg.pid --accesslog access.log
  $ cat hg.pid >> $DAEMON_PIDS

  $ hg -R server debuglfput gz-a.hg
  14ee2f0b3f1d14aeeb2fe037e09fc295c3cf59f5

  $ cat > server/.hg/clonebundles.manifest << EOF
  > largefile://14ee2f0b3f1d14aeeb2fe037e09fc295c3cf59f5 BUNDLESPEC=gzip-v2
  > EOF

  $ hg clone -U http://localhost:$HGPORT largefile-provided --traceback
  applying clone bundle from largefile://14ee2f0b3f1d14aeeb2fe037e09fc295c3cf59f5
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 2 files
  finished applying clone bundle
  searching for changes
  no changes found