view tests/test-encoding.t @ 30764:e75463e3179f

protocol: send application/mercurial-0.2 responses to capable clients

With this commit, the HTTP transport now parses the X-HgProto-<N>
header to determine what media type and compression engine to use for
responses. So far, we only compress responses that are already being
compressed with zlib today (stream response types to specific
commands). We can expand things to cover additional response types
later.

The practical side-effect of this commit is that non-zlib compression
engines will be used if both ends support them. This means if both
ends have zstd support, zstd - not zlib - will be used to compress
data!

When cloning the mozilla-unified repository between a local HTTP
server and client, the benefits of non-zlib compression are quite
noticeable:

  engine     server CPU (s)   client CPU (s)    bundle size
zlib (l=6)      174.1            283.2         1,148,547,026
zstd (l=1)       99.2            267.3         1,127,513,841
zstd (l=3)      103.1            266.9         1,018,861,363
zstd (l=7)      128.3            269.7           919,190,278
zstd (l=10)     162.0               -            894,547,179
none             95.3            277.2         4,097,566,064

The default zstd compression level is 3. So if you deploy zstd
capable Mercurial to your clients and servers and CPU time on
your server is dominated by "getbundle" requests (clients cloning
and pulling) - and my experience at Mozilla tells me this is often
the case - this commit could drastically reduce your server-side
CPU usage *and* save on bandwidth costs!

Another benefit of this change is that server operators can install
*any* compression engine. While it isn't enabled by default, the
"none" compression engine can now be used to disable wire protocol
compression completely. Previously, commands like "getbundle" always
zlib compressed output, adding considerable overhead to generating
responses. If you are on a high speed network and your server is under
high load, it might be advantageous to trade bandwidth for CPU.
Although, zstd at level 1 doesn't use that much CPU, so I'm not
convinced that disabling compression wholesale is worthwhile. And, my
data seems to indicate a slow down on the client without compression.
I suspect this is due to a lack of buffering resulting in an increase
in socket read() calls and/or the fact we're transferring an extra 3 GB
of data (parsing HTTP chunked transfer and processing extra TCP packets
can add up). This is definitely worth investigating and optimizing. But
since the "none" compressor isn't enabled by default, I'm inclined to
punt on this issue.

This commit introduces tons of tests. Some of these should arguably
have been implemented on previous commits. But it was difficult to
test without the server functionality in place.

Test character encoding

  $ hg init t
  $ cd t

we need a repo with some legacy latin-1 changesets

  $ hg unbundle "$TESTDIR/bundles/legacy-encoding.hg"
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 1 files
  (run 'hg update' to get a working copy)
  $ hg co
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ python << EOF
  > f = file('latin-1', 'w'); f.write("latin-1 e' encoded: \xe9"); f.close()
  > f = file('utf-8', 'w'); f.write("utf-8 e' encoded: \xc3\xa9"); f.close()
  > f = file('latin-1-tag', 'w'); f.write("\xe9"); f.close()
  > EOF

should fail with encoding error

  $ echo "plain old ascii" > a
  $ hg st
  M a
  ? latin-1
  ? latin-1-tag
  ? utf-8
  $ HGENCODING=ascii hg ci -l latin-1
  transaction abort!
  rollback completed
  abort: decoding near ' encoded: \xe9': 'ascii' codec can't decode byte 0xe9 in position 20: ordinal not in range(128)! (esc)
  [255]

these should work

  $ echo "latin-1" > a
  $ HGENCODING=latin-1 hg ci -l latin-1
  $ echo "utf-8" > a
  $ HGENCODING=utf-8 hg ci -l utf-8
  $ HGENCODING=latin-1 hg tag `cat latin-1-tag`
  $ HGENCODING=latin-1 hg branch `cat latin-1-tag`
  marked working directory as branch \xe9 (esc)
  (branches are permanent and global, did you want a bookmark?)
  $ HGENCODING=latin-1 hg ci -m 'latin1 branch'
  $ hg -q rollback
  $ HGENCODING=latin-1 hg branch
  \xe9 (esc)
  $ HGENCODING=latin-1 hg ci -m 'latin1 branch'
  $ rm .hg/branch

hg log (ascii)

  $ hg --encoding ascii log
  changeset:   5:a52c0692f24a
  branch:      ?
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin1 branch
  
  changeset:   4:94db611b4196
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added tag ? for changeset ca661e7520de
  
  changeset:   3:ca661e7520de
  tag:         ?
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     utf-8 e' encoded: ?
  
  changeset:   2:650c6f3d55dd
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin-1 e' encoded: ?
  
  changeset:   1:0e5b7e3f9c4a
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     koi8-r: ????? = u'\u0440\u0442\u0443\u0442\u044c'
  
  changeset:   0:1e78a93102a3
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     latin-1 e': ? = u'\xe9'
  

hg log (latin-1)

  $ hg --encoding latin-1 log
  changeset:   5:a52c0692f24a
  branch:      \xe9 (esc)
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin1 branch
  
  changeset:   4:94db611b4196
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added tag \xe9 for changeset ca661e7520de (esc)
  
  changeset:   3:ca661e7520de
  tag:         \xe9 (esc)
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     utf-8 e' encoded: \xe9 (esc)
  
  changeset:   2:650c6f3d55dd
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin-1 e' encoded: \xe9 (esc)
  
  changeset:   1:0e5b7e3f9c4a
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     koi8-r: \xd2\xd4\xd5\xd4\xd8 = u'\\u0440\\u0442\\u0443\\u0442\\u044c' (esc)
  
  changeset:   0:1e78a93102a3
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     latin-1 e': \xe9 = u'\\xe9' (esc)
  

hg log (utf-8)

  $ hg --encoding utf-8 log
  changeset:   5:a52c0692f24a
  branch:      \xc3\xa9 (esc)
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin1 branch
  
  changeset:   4:94db611b4196
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added tag \xc3\xa9 for changeset ca661e7520de (esc)
  
  changeset:   3:ca661e7520de
  tag:         \xc3\xa9 (esc)
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     utf-8 e' encoded: \xc3\xa9 (esc)
  
  changeset:   2:650c6f3d55dd
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin-1 e' encoded: \xc3\xa9 (esc)
  
  changeset:   1:0e5b7e3f9c4a
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     koi8-r: \xc3\x92\xc3\x94\xc3\x95\xc3\x94\xc3\x98 = u'\\u0440\\u0442\\u0443\\u0442\\u044c' (esc)
  
  changeset:   0:1e78a93102a3
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     latin-1 e': \xc3\xa9 = u'\\xe9' (esc)
  

hg tags (ascii)

  $ HGENCODING=ascii hg tags
  tip                                5:a52c0692f24a
  ?                                  3:ca661e7520de

hg tags (latin-1)

  $ HGENCODING=latin-1 hg tags
  tip                                5:a52c0692f24a
  \xe9                                  3:ca661e7520de (esc)

hg tags (utf-8)

  $ HGENCODING=utf-8 hg tags
  tip                                5:a52c0692f24a
  \xc3\xa9                                  3:ca661e7520de (esc)

hg tags (JSON)

  $ hg tags -Tjson
  [
   {
    "node": "a52c0692f24ad921c0a31e1736e7635a8b23b670",
    "rev": 5,
    "tag": "tip",
    "type": ""
   },
   {
    "node": "ca661e7520dec3f5438a63590c350bebadb04989",
    "rev": 3,
    "tag": "\xc3\xa9", (esc)
    "type": ""
   }
  ]

hg branches (ascii)

  $ HGENCODING=ascii hg branches
  ?                              5:a52c0692f24a
  default                        4:94db611b4196 (inactive)

hg branches (latin-1)

  $ HGENCODING=latin-1 hg branches
  \xe9                              5:a52c0692f24a (esc)
  default                        4:94db611b4196 (inactive)

hg branches (utf-8)

  $ HGENCODING=utf-8 hg branches
  \xc3\xa9                              5:a52c0692f24a (esc)
  default                        4:94db611b4196 (inactive)
  $ echo '[ui]' >> .hg/hgrc
  $ echo 'fallbackencoding = koi8-r' >> .hg/hgrc

hg log (utf-8)

  $ HGENCODING=utf-8 hg log
  changeset:   5:a52c0692f24a
  branch:      \xc3\xa9 (esc)
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin1 branch
  
  changeset:   4:94db611b4196
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     Added tag \xc3\xa9 for changeset ca661e7520de (esc)
  
  changeset:   3:ca661e7520de
  tag:         \xc3\xa9 (esc)
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     utf-8 e' encoded: \xc3\xa9 (esc)
  
  changeset:   2:650c6f3d55dd
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     latin-1 e' encoded: \xc3\xa9 (esc)
  
  changeset:   1:0e5b7e3f9c4a
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     koi8-r: \xd1\x80\xd1\x82\xd1\x83\xd1\x82\xd1\x8c = u'\\u0440\\u0442\\u0443\\u0442\\u044c' (esc)
  
  changeset:   0:1e78a93102a3
  user:        test
  date:        Mon Jan 12 13:46:40 1970 +0000
  summary:     latin-1 e': \xd0\x98 = u'\\xe9' (esc)
  

hg log (dolphin)

  $ HGENCODING=dolphin hg log
  abort: unknown encoding: dolphin
  (please check your locale settings)
  [255]
  $ HGENCODING=ascii hg branch `cat latin-1-tag`
  abort: decoding near '\xe9': 'ascii' codec can't decode byte 0xe9 in position 0: ordinal not in range(128)! (esc)
  [255]
  $ cp latin-1-tag .hg/branch
  $ HGENCODING=latin-1 hg ci -m 'auto-promote legacy name'

Test roundtrip encoding of lookup tables when not using UTF-8 (issue2763)

  $ HGENCODING=latin-1 hg up `cat latin-1-tag`
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

  $ cd ..

Test roundtrip encoding/decoding of utf8b for generated data

#if hypothesis

  >>> from hypothesishelpers import *
  >>> from mercurial import encoding
  >>> roundtrips(st.binary(), encoding.fromutf8b, encoding.toutf8b)
  Round trip OK

#endif