wireproto: define and implement HTTP handshake to upgrade protocol
When clients connect to repositories over HTTP, they issue a request
to the well-known URL "?cmd=capabilities" to fetch the repository
capabilities. This is the handshake portion of the HTTP protocol.
This commit defines a mechanism to use that HTTP request to return
information about modern server features.
If a client sends an X-HgUpgrade-* header containing a list of
client-supported API names, the server responds with a response
containing information about available services. This includes
the normal capabilities string. So if the server doesn't support
any newer services, the client can easily fall back.
By advertising supported services from clients, server operators
can see and log what client support exists in the wild. This will
also help with debugging.
The response contains the base path to API services. We know there
are potential issues with the <repo>/api/ URL space conflicting with
hgwebdir and subrepos. By making the API URL dynamic from the
perspective of the client, the URL for APIs is not subject to backwards
compatibility concerns - at least as long as a ?cmd=capabilities request
is made.
We've also defined the ``cbor`` client capability for the X-HgProto-*
header. This MUST be sent in order to get the modern response from
"?cmd=capabilities". During implementation, I initially always sent
an application/mercurial-cbor response. However, the handshake
mechanism will be more future compatible if the client is in charge
of which formats to request. We already perform content negotiation
from X-HgProto-*, so keying off this for the capabilities response
feels appropriate.
In addition, I initially used application/cbor. However, it is
conceivable that a non-Mercurial server could serve application/cbor.
To rule out this possibility, I've invented a new media type that
is Mercurial specific and can't be confused for generic CBOR.
Differential Revision: https://phab.mercurial-scm.org/D3242
#require serve
#testcases sshv1 sshv2
#if sshv2
$ cat >> $HGRCPATH << EOF
> [experimental]
> sshpeer.advertise-v2 = true
> sshserver.support-v2 = true
> EOF
#endif
$ hg init test
$ cd test
$ echo foo>foo
$ hg addremove
adding foo
$ hg commit -m 1
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
$ hg serve -p $HGPORT -d --pid-file=hg.pid
$ cat hg.pid >> $DAEMON_PIDS
$ cd ..
$ hg clone --pull http://foo:bar@localhost:$HGPORT/ copy
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
new changesets 340e38bdcde4
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd copy
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 1 changesets, 1 total revisions
$ hg co
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cat foo
foo
$ hg manifest --debug
2ed2a3912a0b24502043eae84ee4b279c18b90dd 644 foo
$ hg pull
pulling from http://foo@localhost:$HGPORT/
searching for changes
no changes found
$ hg rollback --dry-run --verbose
repository tip rolled back to revision -1 (undo pull: http://foo:***@localhost:$HGPORT/)
Test pull of non-existing 20 character revision specification, making sure plain ascii identifiers
not are encoded like a node:
$ hg pull -r 'xxxxxxxxxxxxxxxxxxxy'
pulling from http://foo@localhost:$HGPORT/
abort: unknown revision 'xxxxxxxxxxxxxxxxxxxy'!
[255]
$ hg pull -r 'xxxxxxxxxxxxxxxxxx y'
pulling from http://foo@localhost:$HGPORT/
abort: unknown revision 'xxxxxxxxxxxxxxxxxx y'!
[255]
Issue622: hg init && hg pull -u URL doesn't checkout default branch
$ cd ..
$ hg init empty
$ cd empty
$ hg pull -u ../test
pulling from ../test
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
new changesets 340e38bdcde4
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
Test 'file:' uri handling:
$ hg pull -q file://../test-does-not-exist
abort: file:// URLs can only refer to localhost
[255]
$ hg pull -q file://../test
abort: file:// URLs can only refer to localhost
[255]
MSYS changes 'file:' into 'file;'
#if no-msys
$ hg pull -q file:../test # no-msys
#endif
It's tricky to make file:// URLs working on every platform with
regular shell commands.
$ URL=`$PYTHON -c "import os; print 'file://foobar' + ('/' + os.getcwd().replace(os.sep, '/')).replace('//', '/') + '/../test'"`
$ hg pull -q "$URL"
abort: file:// URLs can only refer to localhost
[255]
$ URL=`$PYTHON -c "import os; print 'file://localhost' + ('/' + os.getcwd().replace(os.sep, '/')).replace('//', '/') + '/../test'"`
$ hg pull -q "$URL"
SEC: check for unsafe ssh url
$ cat >> $HGRCPATH << EOF
> [ui]
> ssh = sh -c "read l; read l; read l"
> EOF
$ hg pull 'ssh://-oProxyCommand=touch${IFS}owned/path'
pulling from ssh://-oProxyCommand%3Dtouch%24%7BIFS%7Downed/path
abort: potentially unsafe url: 'ssh://-oProxyCommand=touch${IFS}owned/path'
[255]
$ hg pull 'ssh://%2DoProxyCommand=touch${IFS}owned/path'
pulling from ssh://-oProxyCommand%3Dtouch%24%7BIFS%7Downed/path
abort: potentially unsafe url: 'ssh://-oProxyCommand=touch${IFS}owned/path'
[255]
$ hg pull 'ssh://fakehost|touch${IFS}owned/path'
pulling from ssh://fakehost%7Ctouch%24%7BIFS%7Downed/path
abort: no suitable response from remote hg!
[255]
$ hg pull 'ssh://fakehost%7Ctouch%20owned/path'
pulling from ssh://fakehost%7Ctouch%20owned/path
abort: no suitable response from remote hg!
[255]
$ [ ! -f owned ] || echo 'you got owned'
$ cd ..