wireproto: port lookup to wire protocol v2

This is pretty straightforward. We don't yet handle errors because we
don't have an error handling mechanism in place yet.

I'm also tempted to fold this into `known`. We'll come back to this
later.

Differential Revision: https://phab.mercurial-scm.org/D3205

tests/test-wireproto-command-lookup.t

@@ -0,0 +1,55 b''
+  $ . $TESTDIR/wireprotohelpers.sh
+
+  $ hg init server
+  $ enablehttpv2 server
+  $ cd server
+  $ cat >> .hg/hgrc << EOF
+  > [web]
+  > push_ssl = false
+  > allow-push = *
+  > EOF
+  $ hg debugdrawdag << EOF
+  > C D
+  > |/
+  > B
+  > |
+  > A
+  > EOF
+
+  $ hg serve -p $HGPORT -d --pid-file hg.pid -E error.log
+  $ cat hg.pid > $DAEMON_PIDS
+
+lookup for known node works
+
+  $ sendhttpv2peer << EOF
+  > command lookup
+  >     key 426bada5c67598ca65036d57d9e4b64b0c1ce7a0
+  > EOF
+  creating http peer for wire protocol version 2
+  sending lookup command
+  s>     *\r\n (glob)
+  s>     Accept-Encoding: identity\r\n
+  s>     accept: application/mercurial-exp-framing-0003\r\n
+  s>     content-type: application/mercurial-exp-framing-0003\r\n
+  s>     content-length: 73\r\n
+  s>     host: $LOCALIP:$HGPORT\r\n (glob)
+  s>     user-agent: Mercurial debugwireproto\r\n
+  s>     \r\n
+  s>     A\x00\x00\x01\x00\x01\x01\x11\xa2Dargs\xa1CkeyX(426bada5c67598ca65036d57d9e4b64b0c1ce7a0DnameFlookup
+  s> makefile('rb', None)
+  s>     HTTP/1.1 200 OK\r\n
+  s>     Server: testing stub value\r\n
+  s>     Date: $HTTP_DATE$\r\n
+  s>     Content-Type: application/mercurial-exp-framing-0003\r\n
+  s>     Transfer-Encoding: chunked\r\n
+  s>     \r\n
+  s>     1d\r\n
+  s>     *\x00\x01\x00\x02\x01F (glob)
+  s>     TBk\xad\xa5\xc6u\x98\xcae\x03mW\xd9\xe4\xb6K\x0c\x1c\xe7\xa0
+  s>     \r\n
+  received frame(size=*; request=1; stream=2; streamflags=stream-begin; type=bytes-response; flags=eos|cbor) (glob)
+  s>     0\r\n
+  s>     \r\n
+  response: [b'Bk\xad\xa5\xc6u\x98\xcae\x03mW\xd9\xe4\xb6K\x0c\x1c\xe7\xa0']
+
+  $ cat error.log

mercurial/help/internals/wireprotocol.txt

@@ -1778,6 +1778,21 b' The response is a map with bytestring ke'
 
 TODO consider using binary to represent nodes in certain pushkey namespaces.
 
+lookup
+------
+
+Try to resolve a value to a changeset revision.
+
+Unlike ``known`` which operates on changeset nodes, lookup operates on
+node fragments and other names that a user may use.
+
+The command receives the following arguments:
+
+key
+   (bytestring) Value to try to resolve.
+
+On success, returns a bytestring containing the resolved node.
+
 pushkey
 -------
 

mercurial/wireproto.py

@@ -1120,7 +1120,8 b' def listkeys(repo, proto, namespace):'
     d = sorted(repo.listkeys(encoding.tolocal(namespace)).items())
     return wireprototypes.bytesresponse(pushkeymod.encodekeys(d))
 
-@wireprotocommand('lookup', 'key', permission='pull')
+@wireprotocommand('lookup', 'key', permission='pull',
+                  transportpolicy=POLICY_V1_ONLY)
 def lookup(repo, proto, key):
     try:
         k = encoding.tolocal(key)
@@ -1378,6 +1379,20 b' def listkeysv2(repo, proto, namespace=No'
 
     return wireprototypes.cborresponse(keys)
 
+@wireprotocommand('lookup',
+                  args={
+                      'key': b'foo',
+                  },
+                  permission='pull',
+                  transportpolicy=POLICY_V2_ONLY)
+def lookupv2(repo, proto, key):
+    key = encoding.tolocal(key)
+
+    # TODO handle exception.
+    node = repo.lookup(key)
+
+    return wireprototypes.cborresponse(node)
+
 @wireprotocommand('pushkey',
                   args={
                       'namespace': b'ns',

tests/test-wireproto-command-capabilities.t

@@ -30,11 +30,11 b' capabilities request returns an array of'
   s>     \r\n
   s>     *\r\n (glob)
   s>     *\x00\x01\x00\x02\x01F (glob)
-  s>     \xa2Hcommands\xa9Eheads\xa2Dargs\xa1Jpubliconly\xf4Kpermissions\x81DpullEknown\xa2Dargs\xa1Enodes\x81HdeadbeefKpermissions\x81DpullFlookup\xa2Dargs\xa1CkeyFlegacyKpermissions\x81DpullGpushkey\xa2Dargs\xa4CkeyCkeyCnewCnewColdColdInamespaceBnsKpermissions\x81DpullHlistkeys\xa2Dargs\xa1InamespaceBnsKpermissions\x81DpullHunbundle\xa2Dargs\xa1EheadsFlegacyKpermissions\x81DpushIbranchmap\xa2Dargs\xa0Kpermissions\x81DpullIgetbundle\xa2Dargs\xa1A*FlegacyKpermissions\x81DpullLcapabilities\xa2Dargs\xa0Kpermissions\x81DpullKcompression\x82\xa1DnameDzstd\xa1DnameDzlib
+  s>     \xa2Hcommands\xa9Eheads\xa2Dargs\xa1Jpubliconly\xf4Kpermissions\x81DpullEknown\xa2Dargs\xa1Enodes\x81HdeadbeefKpermissions\x81DpullFlookup\xa2Dargs\xa1CkeyCfooKpermissions\x81DpullGpushkey\xa2Dargs\xa4CkeyCkeyCnewCnewColdColdInamespaceBnsKpermissions\x81DpushHlistkeys\xa2Dargs\xa1InamespaceBnsKpermissions\x81DpullHunbundle\xa2Dargs\xa1EheadsFlegacyKpermissions\x81DpushIbranchmap\xa2Dargs\xa0Kpermissions\x81DpullIgetbundle\xa2Dargs\xa1A*FlegacyKpermissions\x81DpullLcapabilities\xa2Dargs\xa0Kpermissions\x81DpullKcompression\x82\xa1DnameDzstd\xa1DnameDzlib
   s>     \r\n
   received frame(size=*; request=1; stream=2; streamflags=stream-begin; type=bytes-response; flags=eos|cbor) (glob)
   s>     0\r\n
   s>     \r\n
-  response: [{b'commands': {b'branchmap': {b'args': {}, b'permissions': [b'pull']}, b'capabilities': {b'args': {}, b'permissions': [b'pull']}, b'getbundle': {b'args': {b'*': b'legacy'}, b'permissions': [b'pull']}, b'heads': {b'args': {b'publiconly': False}, b'permissions': [b'pull']}, b'known': {b'args': {b'nodes': [b'deadbeef']}, b'permissions': [b'pull']}, b'listkeys': {b'args': {b'namespace': b'ns'}, b'permissions': [b'pull']}, b'lookup': {b'args': {b'key': b'legacy'}, b'permissions': [b'pull']}, b'pushkey': {b'args': {b'key': b'key', b'namespace': b'ns', b'new': b'new', b'old': b'old'}, b'permissions': [b'pull']}, b'unbundle': {b'args': {b'heads': b'legacy'}, b'permissions': [b'push']}}, b'compression': [{b'name': b'zstd'}, {b'name': b'zlib'}]}]
+  response: [{b'commands': {b'branchmap': {b'args': {}, b'permissions': [b'pull']}, b'capabilities': {b'args': {}, b'permissions': [b'pull']}, b'getbundle': {b'args': {b'*': b'legacy'}, b'permissions': [b'pull']}, b'heads': {b'args': {b'publiconly': False}, b'permissions': [b'pull']}, b'known': {b'args': {b'nodes': [b'deadbeef']}, b'permissions': [b'pull']}, b'listkeys': {b'args': {b'namespace': b'ns'}, b'permissions': [b'pull']}, b'lookup': {b'args': {b'key': b'foo'}, b'permissions': [b'pull']}, b'pushkey': {b'args': {b'key': b'key', b'namespace': b'ns', b'new': b'new', b'old': b'old'}, b'permissions': [b'push']}, b'unbundle': {b'args': {b'heads': b'legacy'}, b'permissions': [b'push']}}, b'compression': [{b'name': b'zstd'}, {b'name': b'zlib'}]}]
 
   $ cat error.log