bundle2: capture remote stdout while unbundling

When a reply is built, the bundle processing will capture the output of each
handler and sends it to the client in a dedicated part.

As a side effect, this add a "remote: " prefix to destination output on local
push. This is considered okay for now as:

1. bundle2 is still experimental,
2. Matt said he could be okay to change output for bundle2,
3. This keeps the implementation simple.

This changeset does it for stdout only. stderr will be done in a future changeset.

mercurial/bundle2.py

@@ -307,7 +307,21 b' def processbundle(repo, unbundler, trans'
             # risk catching KeyErrors from anything other than the
             # parthandlermapping lookup (any KeyError raised by handler()
             # itself represents a defect of a different variety).
-            handler(op, part)
+            output = None
+            if op.reply is not None:
+                op.ui.pushbuffer()
+                output = ''
+            try:
+                handler(op, part)
+            finally:
+                if output is not None:
+                    output = op.ui.popbuffer()
+            if output:
+                outpart = bundlepart('output',
+                                     advisoryparams=[('in-reply-to',
+                                                      str(part.id))],
+                                     data=output)
+                op.reply.addpart(outpart)
             part.read()
     except Exception:
         if part is not None:
@@ -672,6 +686,12 b' def handlechangegroup(op, inpart):'
     if heads != op.repo.heads():
         raise exchange.PushRaced()
 
+@parthandler('output')
+def handleoutput(op, inpart):
+    """forward output captured on the server to the client"""
+    for line in inpart.read().splitlines():
+        op.ui.write(('remote: %s\n' % line))
+
 @parthandler('replycaps')
 def handlereplycaps(op, inpart):
     """Notify that a reply bundle should be created
@@ -679,3 +699,4 b' def handlereplycaps(op, inpart):'
     Will convey bundle capability at some point too."""
     if op.reply is None:
         op.reply = bundle20(op.ui)
+

tests/test-bundle2.t

@@ -499,28 +499,46 b' unbundle with a reply'
 
   $ hg bundle2 --parts --reply ../parts-reply.hg2
   $ hg unbundle2 ../reply.hg2 < ../parts-reply.hg2
-  The choir starts singing:
-      Patali Dirapata, Cromda Cromda Ripalo, Pata Pata, Ko Ko Ko
-      Bokoro Dipoulito, Rondi Rondi Pepino, Pata Pata, Ko Ko Ko
-      Emana Karassoli, Loucra Loucra Ponponto, Pata Pata, Ko Ko Ko.
-  received ping request (id 5)
   0 unread bytes
   3 total verses sung
 
 The reply is a bundle
 
   $ cat ../reply.hg2
-  HG20\x00\x00\x00\x1e	test:pong\x00\x00\x00\x00\x01\x00\x0b\x01in-reply-to5\x00\x00\x00\x00\x00\x00 (no-eol) (esc)
+  HG20\x00\x00\x00\x1b\x06output\x00\x00\x00\x00\x00\x01\x0b\x01in-reply-to3\x00\x00\x00\xd9The choir starts singing: (esc)
+      Patali Dirapata, Cromda Cromda Ripalo, Pata Pata, Ko Ko Ko
+      Bokoro Dipoulito, Rondi Rondi Pepino, Pata Pata, Ko Ko Ko
+      Emana Karassoli, Loucra Loucra Ponponto, Pata Pata, Ko Ko Ko.
+  \x00\x00\x00\x00\x00\x1e	test:pong\x00\x00\x00\x01\x01\x00\x0b\x01in-reply-to5\x00\x00\x00\x00\x00\x1b\x06output\x00\x00\x00\x02\x00\x01\x0b\x01in-reply-to5\x00\x00\x00\x1dreceived ping request (id 5) (esc)
+  \x00\x00\x00\x00\x00\x00 (no-eol) (esc)
 
 The reply is valid
 
   $ hg statbundle2 < ../reply.hg2
   options count: 0
+    :output:
+      mandatory: 0
+      advisory: 1
+      payload: 217 bytes
     :test:pong:
       mandatory: 1
       advisory: 0
       payload: 0 bytes
-  parts count:   1
+    :output:
+      mandatory: 0
+      advisory: 1
+      payload: 29 bytes
+  parts count:   3
+
+Unbundle the reply to get the output:
+
+  $ hg unbundle2 < ../reply.hg2
+  remote: The choir starts singing:
+  remote:     Patali Dirapata, Cromda Cromda Ripalo, Pata Pata, Ko Ko Ko
+  remote:     Bokoro Dipoulito, Rondi Rondi Pepino, Pata Pata, Ko Ko Ko
+  remote:     Emana Karassoli, Loucra Loucra Ponponto, Pata Pata, Ko Ko Ko.
+  remote: received ping request (id 5)
+  0 unread bytes
 
 Support for changegroup
 ===================================
@@ -646,15 +664,15 b' with reply'
 
   $ hg bundle2 --rev '8+7+5+4' --reply ../rev-rr.hg2
   $ hg unbundle2 ../rev-reply.hg2 < ../rev-rr.hg2
-  adding changesets
-  adding manifests
-  adding file changes
-  added 0 changesets with 0 changes to 3 files
   0 unread bytes
   addchangegroup return: 1
 
   $ cat ../rev-reply.hg2
-  HG20\x00\x00\x00/\x11reply:changegroup\x00\x00\x00\x00\x00\x02\x0b\x01\x06\x01in-reply-to1return1\x00\x00\x00\x00\x00\x00 (no-eol) (esc)
+  HG20\x00\x00\x00/\x11reply:changegroup\x00\x00\x00\x00\x00\x02\x0b\x01\x06\x01in-reply-to1return1\x00\x00\x00\x00\x00\x1b\x06output\x00\x00\x00\x01\x00\x01\x0b\x01in-reply-to1\x00\x00\x00dadding changesets (esc)
+  adding manifests
+  adding file changes
+  added 0 changesets with 0 changes to 3 files
+  \x00\x00\x00\x00\x00\x00 (no-eol) (esc)
 
 Real world exchange
 =====================
@@ -699,10 +717,10 b' push'
   $ hg -R main push other --rev eea13746799a
   pushing to other
   searching for changes
-  adding changesets
-  adding manifests
-  adding file changes
-  added 1 changesets with 0 changes to 0 files (-1 heads)
+  remote: adding changesets
+  remote: adding manifests
+  remote: adding file changes
+  remote: added 1 changesets with 0 changes to 0 files (-1 heads)
 
 pull over ssh
 
@@ -748,6 +766,10 b' push over http'
   $ hg -R main push http://localhost:$HGPORT2/ -r 32af7686d403
   pushing to http://localhost:$HGPORT2/
   searching for changes
+  remote: adding changesets
+  remote: adding manifests
+  remote: adding file changes
+  remote: added 1 changesets with 1 changes to 1 files
   $ cat other-error.log
 
 Check final content.