view tests/test-flagprocessor.t @ 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

# Create server
  $ hg init server
  $ cd server
  $ cat >> .hg/hgrc << EOF
  > [extensions]
  > extension=$TESTDIR/flagprocessorext.py
  > EOF
  $ cd ../

# Clone server and enable extensions
  $ hg clone -q server client
  $ cd client
  $ cat >> .hg/hgrc << EOF
  > [extensions]
  > extension=$TESTDIR/flagprocessorext.py
  > EOF

# Commit file that will trigger the noop extension
  $ echo '[NOOP]' > noop
  $ hg commit -Aqm "noop"

# Commit file that will trigger the base64 extension
  $ echo '[BASE64]' > base64
  $ hg commit -Aqm 'base64'

# Commit file that will trigger the gzip extension
  $ echo '[GZIP]' > gzip
  $ hg commit -Aqm 'gzip'

# Commit file that will trigger noop and base64
  $ echo '[NOOP][BASE64]' > noop-base64
  $ hg commit -Aqm 'noop+base64'

# Commit file that will trigger noop and gzip
  $ echo '[NOOP][GZIP]' > noop-gzip
  $ hg commit -Aqm 'noop+gzip'

# Commit file that will trigger base64 and gzip
  $ echo '[BASE64][GZIP]' > base64-gzip
  $ hg commit -Aqm 'base64+gzip'

# Commit file that will trigger base64, gzip and noop
  $ echo '[BASE64][GZIP][NOOP]' > base64-gzip-noop
  $ hg commit -Aqm 'base64+gzip+noop'

# TEST: ensure the revision data is consistent
  $ hg cat noop
  [NOOP]
  $ hg debugdata noop 0
  [NOOP]

  $ hg cat -r . base64
  [BASE64]
  $ hg debugdata base64 0
  W0JBU0U2NF0K (no-eol)

  $ hg cat -r . gzip
  [GZIP]
  $ hg debugdata gzip 0
  x\x9c\x8bv\x8f\xf2\x0c\x88\xe5\x02\x00\x08\xc8\x01\xfd (no-eol) (esc)

  $ hg cat -r . noop-base64
  [NOOP][BASE64]
  $ hg debugdata noop-base64 0
  W05PT1BdW0JBU0U2NF0K (no-eol)

  $ hg cat -r . noop-gzip
  [NOOP][GZIP]
  $ hg debugdata noop-gzip 0
  x\x9c\x8b\xf6\xf3\xf7\x0f\x88\x8dv\x8f\xf2\x0c\x88\xe5\x02\x00\x1dH\x03\xf1 (no-eol) (esc)

  $ hg cat -r . base64-gzip
  [BASE64][GZIP]
  $ hg debugdata base64-gzip 0
  eJyLdnIMdjUziY12j/IMiOUCACLBBDo= (no-eol)

  $ hg cat -r . base64-gzip-noop
  [BASE64][GZIP][NOOP]
  $ hg debugdata base64-gzip-noop 0
  eJyLdnIMdjUziY12j/IMiI328/cPiOUCAESjBi4= (no-eol)

# Push to the server
  $ hg push
  pushing to $TESTTMP/server
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 7 changesets with 7 changes to 7 files

# Initialize new client (not cloning) and setup extension
  $ cd ..
  $ hg init client2
  $ cd client2
  $ cat >> .hg/hgrc << EOF
  > [paths]
  > default = $TESTTMP/server
  > [extensions]
  > extension=$TESTDIR/flagprocessorext.py
  > EOF

# Pull from server and update to latest revision
  $ hg pull default
  pulling from $TESTTMP/server
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 7 changesets with 7 changes to 7 files
  new changesets 07b1b9442c5b:6e48f4215d24
  (run 'hg update' to get a working copy)
  $ hg update
  7 files updated, 0 files merged, 0 files removed, 0 files unresolved

# TEST: ensure the revision data is consistent
  $ hg cat noop
  [NOOP]
  $ hg debugdata noop 0
  [NOOP]

  $ hg cat -r . base64
  [BASE64]
  $ hg debugdata base64 0
  W0JBU0U2NF0K (no-eol)

  $ hg cat -r . gzip
  [GZIP]
  $ hg debugdata gzip 0
  x\x9c\x8bv\x8f\xf2\x0c\x88\xe5\x02\x00\x08\xc8\x01\xfd (no-eol) (esc)

  $ hg cat -r . noop-base64
  [NOOP][BASE64]
  $ hg debugdata noop-base64 0
  W05PT1BdW0JBU0U2NF0K (no-eol)

  $ hg cat -r . noop-gzip
  [NOOP][GZIP]
  $ hg debugdata noop-gzip 0
  x\x9c\x8b\xf6\xf3\xf7\x0f\x88\x8dv\x8f\xf2\x0c\x88\xe5\x02\x00\x1dH\x03\xf1 (no-eol) (esc)

  $ hg cat -r . base64-gzip
  [BASE64][GZIP]
  $ hg debugdata base64-gzip 0
  eJyLdnIMdjUziY12j/IMiOUCACLBBDo= (no-eol)

  $ hg cat -r . base64-gzip-noop
  [BASE64][GZIP][NOOP]
  $ hg debugdata base64-gzip-noop 0
  eJyLdnIMdjUziY12j/IMiI328/cPiOUCAESjBi4= (no-eol)

# TEST: ensure a missing processor is handled
  $ echo '[FAIL][BASE64][GZIP][NOOP]' > fail-base64-gzip-noop
  $ hg commit -Aqm 'fail+base64+gzip+noop'
  abort: missing processor for flag '0x1'!
  [255]
  $ rm fail-base64-gzip-noop

# TEST: ensure we cannot register several flag processors on the same flag
  $ cat >> .hg/hgrc << EOF
  > [extensions]
  > extension=$TESTDIR/flagprocessorext.py
  > duplicate=$TESTDIR/flagprocessorext.py
  > EOF
  $ hg debugrebuilddirstate
  Traceback (most recent call last):
    File "*/mercurial/extensions.py", line *, in _runextsetup (glob)
      extsetup(ui)
    File "*/tests/flagprocessorext.py", line *, in extsetup (glob)
      validatehash,
    File "*/mercurial/revlog.py", line *, in addflagprocessor (glob)
      raise error.Abort(msg)
  Abort: cannot register multiple processors on flag '0x8'.
  *** failed to set up extension duplicate: cannot register multiple processors on flag '0x8'.
  $ hg st 2>&1 | egrep 'cannot register multiple processors|flagprocessorext'
    File "*/tests/flagprocessorext.py", line *, in extsetup (glob)
  Abort: cannot register multiple processors on flag '0x8'.
  *** failed to set up extension duplicate: cannot register multiple processors on flag '0x8'.
    File "*/tests/flagprocessorext.py", line *, in b64decode (glob)

  $ cd ..

# TEST: bundle repo
  $ hg init bundletest
  $ cd bundletest

  $ cat >> .hg/hgrc << EOF
  > [extensions]
  > flagprocessor=$TESTDIR/flagprocessorext.py
  > EOF

  $ for i in 0 single two three 4; do
  >   echo '[BASE64]a-bit-longer-'$i > base64
  >   hg commit -m base64-$i -A base64
  > done

  $ hg update 2 -q
  $ echo '[BASE64]a-bit-longer-branching' > base64
  $ hg commit -q -m branching

  $ hg bundle --base 1 bundle.hg
  4 changesets found
  $ hg --config extensions.strip= strip -r 2 --no-backup --force -q
  $ hg -R bundle.hg log --stat -T '{rev} {desc}\n' base64
  5 branching
   base64 |  2 +-
   1 files changed, 1 insertions(+), 1 deletions(-)
  
  4 base64-4
   base64 |  2 +-
   1 files changed, 1 insertions(+), 1 deletions(-)
  
  3 base64-three
   base64 |  2 +-
   1 files changed, 1 insertions(+), 1 deletions(-)
  
  2 base64-two
   base64 |  2 +-
   1 files changed, 1 insertions(+), 1 deletions(-)
  
  1 base64-single
   base64 |  2 +-
   1 files changed, 1 insertions(+), 1 deletions(-)
  
  0 base64-0
   base64 |  1 +
   1 files changed, 1 insertions(+), 0 deletions(-)
  

  $ hg bundle -R bundle.hg --base 1 bundle-again.hg -q
  $ hg -R bundle-again.hg log --stat -T '{rev} {desc}\n' base64
  5 branching
   base64 |  2 +-
   1 files changed, 1 insertions(+), 1 deletions(-)
  
  4 base64-4
   base64 |  2 +-
   1 files changed, 1 insertions(+), 1 deletions(-)
  
  3 base64-three
   base64 |  2 +-
   1 files changed, 1 insertions(+), 1 deletions(-)
  
  2 base64-two
   base64 |  2 +-
   1 files changed, 1 insertions(+), 1 deletions(-)
  
  1 base64-single
   base64 |  2 +-
   1 files changed, 1 insertions(+), 1 deletions(-)
  
  0 base64-0
   base64 |  1 +
   1 files changed, 1 insertions(+), 0 deletions(-)
  
  $ rm bundle.hg bundle-again.hg

# TEST: hg status

  $ hg status
  $ hg diff