view tests/test-push-cgi.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

#require no-msys # MSYS will translate web paths as if they were file paths

This is a test of the push wire protocol over CGI-based hgweb.

initialize repository

  $ hg init r
  $ cd r
  $ echo a > a
  $ hg ci -A -m "0"
  adding a
  $ echo '[web]' > .hg/hgrc
  $ echo 'allow_push = *' >> .hg/hgrc
  $ echo 'push_ssl = false' >> .hg/hgrc

create hgweb invocation script

  $ cat >hgweb.cgi <<HGWEB
  > import cgitb
  > cgitb.enable()
  > from mercurial import demandimport; demandimport.enable()
  > from mercurial.hgweb import hgweb
  > from mercurial.hgweb import wsgicgi
  > application = hgweb('.', 'test repository')
  > wsgicgi.launch(application)
  > HGWEB
  $ chmod 755 hgweb.cgi

test preparation

  $ . "$TESTDIR/cgienv"
  $ REQUEST_METHOD="POST"; export REQUEST_METHOD
  $ CONTENT_TYPE="application/octet-stream"; export CONTENT_TYPE
  $ hg bundle --type v1 --all bundle.hg
  1 changesets found
  $ CONTENT_LENGTH=279; export CONTENT_LENGTH;

expect failure because heads doesn't match (formerly known as 'unsynced changes')

  $ QUERY_STRING="cmd=unbundle&heads=0000000000000000000000000000000000000000"; export QUERY_STRING
  $ $PYTHON hgweb.cgi <bundle.hg >page1 2>&1
  $ cat page1
  Status: 200 Script output follows\r (esc)
  Content-Type: application/mercurial-0.1\r (esc)
  Content-Length: 64\r (esc)
  \r (esc)
  0
  repository changed while preparing changes - please try again

successful force push

  $ QUERY_STRING="cmd=unbundle&heads=666f726365"; export QUERY_STRING
  $ $PYTHON hgweb.cgi <bundle.hg >page2 2>&1
  $ cat page2
  Status: 200 Script output follows\r (esc)
  Content-Type: application/mercurial-0.1\r (esc)
  Content-Length: 102\r (esc)
  \r (esc)
  1
  adding changesets
  adding manifests
  adding file changes
  added 0 changesets with 0 changes to 1 files

successful push, list of heads

  $ QUERY_STRING="cmd=unbundle&heads=f7b1eb17ad24730a1651fccd46c43826d1bbc2ac"; export QUERY_STRING
  $ $PYTHON hgweb.cgi <bundle.hg >page3 2>&1
  $ cat page3
  Status: 200 Script output follows\r (esc)
  Content-Type: application/mercurial-0.1\r (esc)
  Content-Length: 102\r (esc)
  \r (esc)
  1
  adding changesets
  adding manifests
  adding file changes
  added 0 changesets with 0 changes to 1 files

successful push, SHA1 hash of heads (unbundlehash capability)

  $ QUERY_STRING="cmd=unbundle&heads=686173686564 5a785a5f9e0d433b88ed862b206b011b0c3a9d13"; export QUERY_STRING
  $ $PYTHON hgweb.cgi <bundle.hg >page4 2>&1
  $ cat page4
  Status: 200 Script output follows\r (esc)
  Content-Type: application/mercurial-0.1\r (esc)
  Content-Length: 102\r (esc)
  \r (esc)
  1
  adding changesets
  adding manifests
  adding file changes
  added 0 changesets with 0 changes to 1 files

  $ cd ..