annotate tests/test-narrow-merge.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

#testcases flat tree

  $ . "$TESTDIR/narrow-library.sh"

#if tree
  $ cat << EOF >> $HGRCPATH
  > [experimental]
  > treemanifest = 1
  > EOF
#endif

create full repo

  $ hg init master
  $ cd master
  $ cat >> .hg/hgrc <<EOF
  > [narrow]
  > serveellipses=True
  > EOF

  $ mkdir inside
  $ echo inside1 > inside/f1
  $ echo inside2 > inside/f2
  $ mkdir outside
  $ echo outside1 > outside/f1
  $ echo outside2 > outside/f2
  $ hg ci -Aqm 'initial'

  $ echo modified > inside/f1
  $ hg ci -qm 'modify inside/f1'

  $ hg update -q 0
  $ echo modified > inside/f2
  $ hg ci -qm 'modify inside/f2'

  $ hg update -q 0
  $ echo modified2 > inside/f1
  $ hg ci -qm 'conflicting inside/f1'

  $ hg update -q 0
  $ echo modified > outside/f1
  $ hg ci -qm 'modify outside/f1'

  $ hg update -q 0
  $ echo modified2 > outside/f1
  $ hg ci -qm 'conflicting outside/f1'

  $ cd ..

  $ hg clone --narrow ssh://user@dummy/master narrow --include inside
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 6 changesets with 5 changes to 2 files (+4 heads)
  new changesets *:* (glob)
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd narrow

  $ hg update -q 0

Can merge in when no files outside narrow spec are involved

  $ hg update -q 'desc("modify inside/f1")'
  $ hg merge 'desc("modify inside/f2")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg commit -m 'merge inside changes'

Can merge conflicting changes inside narrow spec

  $ hg update -q 'desc("modify inside/f1")'
  $ hg merge 'desc("conflicting inside/f1")' 2>&1 | egrep -v '(warning:|incomplete!)'
  merging inside/f1
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
  $ echo modified3 > inside/f1
  $ hg resolve -m
  (no more unresolved files)
  $ hg commit -m 'merge inside/f1'

TODO: Can merge non-conflicting changes outside narrow spec

  $ hg update -q 'desc("modify inside/f1")'
  $ hg merge 'desc("modify outside/f1")'
  abort: merge affects file 'outside/f1' outside narrow, which is not yet supported (flat !)
  abort: merge affects file 'outside/' outside narrow, which is not yet supported (tree !)
  (merging in the other direction may work)
  [255]

  $ hg update -q 'desc("modify outside/f1")'
  $ hg merge 'desc("modify inside/f1")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -m 'merge from inside to outside'

Refuses merge of conflicting outside changes

  $ hg update -q 'desc("modify outside/f1")'
  $ hg merge 'desc("conflicting outside/f1")'
  abort: conflict in file 'outside/f1' is outside narrow clone (flat !)
  abort: conflict in file 'outside/' is outside narrow clone (tree !)
  [255]