view tests/test-debugcommands.t @ 36426:23d12524a202

http: drop custom http client logic

Eight and a half years ago, as my starter bug on code.google.com, I
investigated a mysterious "broken pipe" error from seemingly random
clients[0]. That investigation revealed a tragic story: the Python
standard library's httplib was (and remains) barely functional. During
large POSTs, if a server responds early with an error (even a
permission denied error!) the client only notices that the server
closed the connection and everything breaks. Such server behavior is
implicitly legal under RFC 2616 (the latest HTTP RFC as of when I was
last working on this), and my understanding is that later RFCs have
made it explicitly legal to respond early with any status code outside
the 2xx range.

I embarked, probably foolishly, on a journey to write a new http
library with better overall behavior. The http library appears to work
well in most cases, but it can get confused in the presence of
proxies, and it depends on select(2) which limits its utility if a lot
of file descriptors are open. I haven't touched the http library in
almost two years, and in the interim the Python community has
discovered a better way[1] of writing network code. In theory some day
urllib3 will have its own home-grown http library built on h11[2], or
we could do that. Either way, it's time to declare our current
confusingly-named "http2" client logic and move on. I do hope to
revisit this some day: it's still garbage that we can't even respond
with a 401 or 403 without reading the entire POST body from the
client, but the goalposts on writing a new http client library have
moved substantially. We're almost certainly better off just switching
to requests and eventually picking up their http fixes than trying to
live with something that realistically only we'll ever use. Another
approach would be to write an adapter so that Mercurial can use pycurl
if it's installed. Neither of those approaches seem like they should
be investigated prior to a release of Mercurial that works on Python
3: that's where the mindshare is going to be for any improvements to
the state of the http client art.

0: http://web.archive.org/web/20130501031801/http://code.google.com/p/support/issues/detail?id=2716
1: http://sans-io.readthedocs.io/
2: https://github.com/njsmith/h11

Differential Revision: https://phab.mercurial-scm.org/D2444

  $ cat << EOF >> $HGRCPATH
  > [ui]
  > interactive=yes
  > [format]
  > usegeneraldelta=yes
  > EOF

  $ hg init debugrevlog
  $ cd debugrevlog
  $ echo a > a
  $ hg ci -Am adda
  adding a
  $ hg debugrevlog -m
  format : 1
  flags  : inline, generaldelta
  
  revisions     :  1
      merges    :  0 ( 0.00%)
      normal    :  1 (100.00%)
  revisions     :  1
      full      :  1 (100.00%)
      deltas    :  0 ( 0.00%)
  revision size : 44
      full      : 44 (100.00%)
      deltas    :  0 ( 0.00%)
  
  chunks        :  1
      0x75 (u)  :  1 (100.00%)
  chunks size   : 44
      0x75 (u)  : 44 (100.00%)
  
  avg chain length  :  0
  max chain length  :  0
  max chain reach   : 44
  compression ratio :  0
  
  uncompressed data size (min/max/avg) : 43 / 43 / 43
  full revision size (min/max/avg)     : 44 / 44 / 44
  delta size (min/max/avg)             : 0 / 0 / 0

Test debugindex, with and without the --debug flag
  $ hg debugindex a
     rev    offset  length  ..... linkrev nodeid       p1           p2 (re)
       0         0       3   ....       0 b789fdd96dc2 000000000000 000000000000 (re)
  $ hg --debug debugindex a
     rev    offset  length  ..... linkrev nodeid                                   p1                                       p2 (re)
       0         0       3   ....       0 b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 0000000000000000000000000000000000000000 0000000000000000000000000000000000000000 (re)
  $ hg debugindex -f 1 a
     rev flag   offset   length     size  .....   link     p1     p2       nodeid (re)
       0 0000        0        3        2   ....      0     -1     -1 b789fdd96dc2 (re)
  $ hg --debug debugindex -f 1 a
     rev flag   offset   length     size  .....   link     p1     p2                                   nodeid (re)
       0 0000        0        3        2   ....      0     -1     -1 b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 (re)

debugdelta chain basic output

  $ hg debugdeltachain -m
      rev  chain# chainlen     prev   delta       size    rawsize  chainsize     ratio   lindist extradist extraratio
        0       1        1       -1    base         44         43         44   1.02326        44         0    0.00000

  $ hg debugdeltachain -m -T '{rev} {chainid} {chainlen}\n'
  0 1 1

  $ hg debugdeltachain -m -Tjson
  [
   {
    "chainid": 1,
    "chainlen": 1,
    "chainratio": 1.02325581395,
    "chainsize": 44,
    "compsize": 44,
    "deltatype": "base",
    "extradist": 0,
    "extraratio": 0.0,
    "lindist": 44,
    "prevrev": -1,
    "rev": 0,
    "uncompsize": 43
   }
  ]

debugdelta chain with sparse read enabled

  $ cat >> $HGRCPATH <<EOF
  > [experimental]
  > sparse-read = True
  > EOF
  $ hg debugdeltachain -m
      rev  chain# chainlen     prev   delta       size    rawsize  chainsize     ratio   lindist extradist extraratio   readsize largestblk rddensity srchunks
        0       1        1       -1    base         44         43         44   1.02326        44         0    0.00000         44         44   1.00000        1

  $ hg debugdeltachain -m -T '{rev} {chainid} {chainlen} {readsize} {largestblock} {readdensity}\n'
  0 1 1 44 44 1.0

  $ hg debugdeltachain -m -Tjson
  [
   {
    "chainid": 1,
    "chainlen": 1,
    "chainratio": 1.02325581395,
    "chainsize": 44,
    "compsize": 44,
    "deltatype": "base",
    "extradist": 0,
    "extraratio": 0.0,
    "largestblock": 44,
    "lindist": 44,
    "prevrev": -1,
    "readdensity": 1.0,
    "readsize": 44,
    "rev": 0,
    "srchunks": 1,
    "uncompsize": 43
   }
  ]

  $ printf "This test checks things.\n" >> a
  $ hg ci -m a
  $ hg branch other
  marked working directory as branch other
  (branches are permanent and global, did you want a bookmark?)
  $ for i in `$TESTDIR/seq.py 5`; do
  >   printf "shorter ${i}" >> a
  >   hg ci -m "a other:$i"
  >   hg up -q default
  >   printf "for the branch default we want longer chains: ${i}" >> a
  >   hg ci -m "a default:$i"
  >   hg up -q other
  > done
  $ hg debugdeltachain a -T '{rev} {srchunks}\n' \
  >    --config experimental.sparse-read.density-threshold=0.50 \
  >    --config experimental.sparse-read.min-gap-size=0
  0 1
  1 1
  2 1
  3 1
  4 1
  5 1
  6 1
  7 1
  8 1
  9 1
  10 2
  11 1
  $ hg --config extensions.strip= strip --no-backup -r 1
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

Test max chain len
  $ cat >> $HGRCPATH << EOF
  > [format]
  > maxchainlen=4
  > EOF

  $ printf "This test checks if maxchainlen config value is respected also it can serve as basic test for debugrevlog -d <file>.\n" >> a
  $ hg ci -m a
  $ printf "b\n" >> a
  $ hg ci -m a
  $ printf "c\n" >> a
  $ hg ci -m a
  $ printf "d\n" >> a
  $ hg ci -m a
  $ printf "e\n" >> a
  $ hg ci -m a
  $ printf "f\n" >> a
  $ hg ci -m a
  $ printf 'g\n' >> a
  $ hg ci -m a
  $ printf 'h\n' >> a
  $ hg ci -m a
  $ hg debugrevlog -d a
  # rev p1rev p2rev start   end deltastart base   p1   p2 rawsize totalsize compression heads chainlen
      0    -1    -1     0   ???          0    0    0    0     ???      ????           ?     1        0 (glob)
      1     0    -1   ???   ???          0    0    0    0     ???      ????           ?     1        1 (glob)
      2     1    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        2 (glob)
      3     2    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        3 (glob)
      4     3    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        4 (glob)
      5     4    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        0 (glob)
      6     5    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        1 (glob)
      7     6    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        2 (glob)
      8     7    -1   ???   ???        ???  ???  ???    0     ???      ????           ?     1        3 (glob)

Test debuglocks command:

  $ hg debuglocks
  lock:  free
  wlock: free

* Test setting the lock

waitlock <file> will wait for file to be created. If it isn't in a reasonable
amount of time, displays error message and returns 1
  $ waitlock() {
  >     start=`date +%s`
  >     timeout=5
  >     while [ \( ! -f $1 \) -a \( ! -L $1 \) ]; do
  >         now=`date +%s`
  >         if [ "`expr $now - $start`" -gt $timeout ]; then
  >             echo "timeout: $1 was not created in $timeout seconds"
  >             return 1
  >         fi
  >         sleep 0.1
  >     done
  > }
  $ dolock() {
  >     {
  >         waitlock .hg/unlock
  >         rm -f .hg/unlock
  >         echo y
  >     } | hg debuglocks "$@" > /dev/null
  > }
  $ dolock -s &
  $ waitlock .hg/store/lock

  $ hg debuglocks
  lock:  user *, process * (*s) (glob)
  wlock: free
  [1]
  $ touch .hg/unlock
  $ wait
  $ [ -f .hg/store/lock ] || echo "There is no lock"
  There is no lock

* Test setting the wlock

  $ dolock -S &
  $ waitlock .hg/wlock

  $ hg debuglocks
  lock:  free
  wlock: user *, process * (*s) (glob)
  [1]
  $ touch .hg/unlock
  $ wait
  $ [ -f .hg/wlock ] || echo "There is no wlock"
  There is no wlock

* Test setting both locks

  $ dolock -Ss &
  $ waitlock .hg/wlock && waitlock .hg/store/lock

  $ hg debuglocks
  lock:  user *, process * (*s) (glob)
  wlock: user *, process * (*s) (glob)
  [2]

* Test failing to set a lock

  $ hg debuglocks -s
  abort: lock is already held
  [255]

  $ hg debuglocks -S
  abort: wlock is already held
  [255]

  $ touch .hg/unlock
  $ wait

  $ hg debuglocks
  lock:  free
  wlock: free

* Test forcing the lock

  $ dolock -s &
  $ waitlock .hg/store/lock

  $ hg debuglocks
  lock:  user *, process * (*s) (glob)
  wlock: free
  [1]

  $ hg debuglocks -L

  $ hg debuglocks
  lock:  free
  wlock: free

  $ touch .hg/unlock
  $ wait

* Test forcing the wlock

  $ dolock -S &
  $ waitlock .hg/wlock

  $ hg debuglocks
  lock:  free
  wlock: user *, process * (*s) (glob)
  [1]

  $ hg debuglocks -W

  $ hg debuglocks
  lock:  free
  wlock: free

  $ touch .hg/unlock
  $ wait

Test WdirUnsupported exception

  $ hg debugdata -c ffffffffffffffffffffffffffffffffffffffff
  abort: working directory revision cannot be specified
  [255]

Test cache warming command

  $ rm -rf .hg/cache/
  $ hg debugupdatecaches --debug
  updating the branch cache
  $ ls -r .hg/cache/*
  .hg/cache/rbc-revs-v1
  .hg/cache/rbc-names-v1
  .hg/cache/branch2-served

  $ cd ..

Test internal debugstacktrace command

  $ cat > debugstacktrace.py << EOF
  > from __future__ import absolute_import
  > import sys
  > from mercurial import util
  > def f():
  >     util.debugstacktrace(f=sys.stdout)
  >     g()
  > def g():
  >     util.dst('hello from g\\n', skip=1)
  >     h()
  > def h():
  >     util.dst('hi ...\\nfrom h hidden in g', 1, depth=2)
  > f()
  > EOF
  $ $PYTHON debugstacktrace.py
  stacktrace at:
   debugstacktrace.py:12 in * (glob)
   debugstacktrace.py:5  in f
  hello from g at:
   debugstacktrace.py:12 in * (glob)
   debugstacktrace.py:6  in f
  hi ...
  from h hidden in g at:
   debugstacktrace.py:6 in f
   debugstacktrace.py:9 in g

Test debugcapabilities command:

  $ hg debugcapabilities ./debugrevlog/
  Main capabilities:
    branchmap
    $USUAL_BUNDLE2_CAPS$
    getbundle
    known
    lookup
    pushkey
    unbundle
  Bundle2 capabilities:
    HG20
    bookmarks
    changegroup
      01
      02
    digests
      md5
      sha1
      sha512
    error
      abort
      unsupportedcontent
      pushraced
      pushkey
    hgtagsfnodes
    listkeys
    phases
      heads
    pushkey
    remote-changegroup
      http
      https
    stream
      v2

Test debugpeer

  $ hg --config ui.ssh="\"$PYTHON\" \"$TESTDIR/dummyssh\"" debugpeer ssh://user@dummy/debugrevlog
  url: ssh://user@dummy/debugrevlog
  local: no
  pushable: yes

  $ hg --config ui.ssh="\"$PYTHON\" \"$TESTDIR/dummyssh\"" --debug debugpeer ssh://user@dummy/debugrevlog
  running "*" "*/tests/dummyssh" 'user@dummy' 'hg -R debugrevlog serve --stdio' (glob) (no-windows !)
  running "*" "*\tests/dummyssh" "user@dummy" "hg -R debugrevlog serve --stdio" (glob) (windows !)
  devel-peer-request: hello
  sending hello command
  devel-peer-request: between
  devel-peer-request:   pairs: 81 bytes
  sending between command
  remote: 384
  remote: capabilities: lookup changegroupsubset branchmap pushkey known getbundle unbundlehash batch streamreqs=generaldelta,revlogv1 $USUAL_BUNDLE2_CAPS_SERVER$ unbundle=HG10GZ,HG10BZ,HG10UN
  remote: 1
  url: ssh://user@dummy/debugrevlog
  local: no
  pushable: yes