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
Create configuration
$ echo "[ui]" >> $HGRCPATH
$ echo "interactive=true" >> $HGRCPATH
help qrefresh (no record)
$ echo "[extensions]" >> $HGRCPATH
$ echo "mq=" >> $HGRCPATH
$ hg help qrefresh
hg qrefresh [-I] [-X] [-e] [-m TEXT] [-l FILE] [-s] [FILE]...
update the current patch
If any file patterns are provided, the refreshed patch will contain only
the modifications that match those patterns; the remaining modifications
will remain in the working directory.
If -s/--short is specified, files currently included in the patch will be
refreshed just like matched files and remain in the patch.
If -e/--edit is specified, Mercurial will start your configured editor for
you to enter a message. In case qrefresh fails, you will find a backup of
your message in ".hg/last-message.txt".
hg add/remove/copy/rename work as usual, though you might want to use git-
style patches (-g/--git or [diff] git=1) to track copies and renames. See
the diffs help topic for more information on the git diff format.
Returns 0 on success.
options ([+] can be repeated):
-e --edit invoke editor on commit messages
-g --git use git extended diff format
-s --short refresh only files already in the patch and
specified files
-U --currentuser add/update author field in patch with current user
-u --user USER add/update author field in patch with given user
-D --currentdate add/update date field in patch with current date
-d --date DATE add/update date field in patch with given date
-I --include PATTERN [+] include names matching the given patterns
-X --exclude PATTERN [+] exclude names matching the given patterns
-m --message TEXT use text as commit message
-l --logfile FILE read commit message from file
(some details hidden, use --verbose to show complete help)
help qrefresh (record)
$ echo "record=" >> $HGRCPATH
$ hg help qrefresh
hg qrefresh [-I] [-X] [-e] [-m TEXT] [-l FILE] [-s] [FILE]...
update the current patch
If any file patterns are provided, the refreshed patch will contain only
the modifications that match those patterns; the remaining modifications
will remain in the working directory.
If -s/--short is specified, files currently included in the patch will be
refreshed just like matched files and remain in the patch.
If -e/--edit is specified, Mercurial will start your configured editor for
you to enter a message. In case qrefresh fails, you will find a backup of
your message in ".hg/last-message.txt".
hg add/remove/copy/rename work as usual, though you might want to use git-
style patches (-g/--git or [diff] git=1) to track copies and renames. See
the diffs help topic for more information on the git diff format.
Returns 0 on success.
options ([+] can be repeated):
-e --edit invoke editor on commit messages
-g --git use git extended diff format
-s --short refresh only files already in the patch and
specified files
-U --currentuser add/update author field in patch with current user
-u --user USER add/update author field in patch with given user
-D --currentdate add/update date field in patch with current date
-d --date DATE add/update date field in patch with given date
-I --include PATTERN [+] include names matching the given patterns
-X --exclude PATTERN [+] exclude names matching the given patterns
-m --message TEXT use text as commit message
-l --logfile FILE read commit message from file
-i --interactive interactively select changes to refresh
(some details hidden, use --verbose to show complete help)
$ hg init a
$ cd a
Base commit
$ cat > 1.txt <<EOF
> 1
> 2
> 3
> 4
> 5
> EOF
$ cat > 2.txt <<EOF
> a
> b
> c
> d
> e
> f
> EOF
$ mkdir dir
$ cat > dir/a.txt <<EOF
> hello world
>
> someone
> up
> there
> loves
> me
> EOF
$ hg add 1.txt 2.txt dir/a.txt
$ hg commit -m aaa
$ hg qrecord --config ui.interactive=false patch
abort: running non-interactively, use qnew instead
[255]
$ hg qnew -i --config ui.interactive=false patch
abort: running non-interactively
[255]
$ hg qnew -d '0 0' patch
Changing files
$ sed -e 's/2/2 2/;s/4/4 4/' 1.txt > 1.txt.new
$ sed -e 's/b/b b/' 2.txt > 2.txt.new
$ sed -e 's/hello world/hello world!/' dir/a.txt > dir/a.txt.new
$ mv -f 1.txt.new 1.txt
$ mv -f 2.txt.new 2.txt
$ mv -f dir/a.txt.new dir/a.txt
Whole diff
$ hg diff --nodates
diff -r ed27675cb5df 1.txt
--- a/1.txt
+++ b/1.txt
@@ -1,5 +1,5 @@
1
-2
+2 2
3
-4
+4 4
5
diff -r ed27675cb5df 2.txt
--- a/2.txt
+++ b/2.txt
@@ -1,5 +1,5 @@
a
-b
+b b
c
d
e
diff -r ed27675cb5df dir/a.txt
--- a/dir/a.txt
+++ b/dir/a.txt
@@ -1,4 +1,4 @@
-hello world
+hello world!
someone
up
partial qrefresh
$ hg qrefresh -i --config ui.interactive=false
abort: running non-interactively
[255]
$ hg qrefresh -i -d '0 0' <<EOF
> y
> y
> n
> y
> y
> n
> EOF
diff --git a/1.txt b/1.txt
2 hunks, 2 lines changed
examine changes to '1.txt'? [Ynesfdaq?] y
@@ -1,3 +1,3 @@
1
-2
+2 2
3
record change 1/4 to '1.txt'? [Ynesfdaq?] y
@@ -3,3 +3,3 @@
3
-4
+4 4
5
record change 2/4 to '1.txt'? [Ynesfdaq?] n
diff --git a/2.txt b/2.txt
1 hunks, 1 lines changed
examine changes to '2.txt'? [Ynesfdaq?] y
@@ -1,5 +1,5 @@
a
-b
+b b
c
d
e
record change 3/4 to '2.txt'? [Ynesfdaq?] y
diff --git a/dir/a.txt b/dir/a.txt
1 hunks, 1 lines changed
examine changes to 'dir/a.txt'? [Ynesfdaq?] n
After partial qrefresh 'tip'
$ hg tip -p
changeset: 1:0738af1a8211
tag: patch
tag: qbase
tag: qtip
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: [mq]: patch
diff -r 1fd39ab63a33 -r 0738af1a8211 1.txt
--- a/1.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/1.txt Thu Jan 01 00:00:00 1970 +0000
@@ -1,5 +1,5 @@
1
-2
+2 2
3
4
5
diff -r 1fd39ab63a33 -r 0738af1a8211 2.txt
--- a/2.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/2.txt Thu Jan 01 00:00:00 1970 +0000
@@ -1,5 +1,5 @@
a
-b
+b b
c
d
e
After partial qrefresh 'diff'
$ hg diff --nodates
diff -r 0738af1a8211 1.txt
--- a/1.txt
+++ b/1.txt
@@ -1,5 +1,5 @@
1
2 2
3
-4
+4 4
5
diff -r 0738af1a8211 dir/a.txt
--- a/dir/a.txt
+++ b/dir/a.txt
@@ -1,4 +1,4 @@
-hello world
+hello world!
someone
up
qrefresh interactively everything else
$ hg qrefresh -i -d '0 0' <<EOF
> y
> y
> y
> y
> EOF
diff --git a/1.txt b/1.txt
1 hunks, 1 lines changed
examine changes to '1.txt'? [Ynesfdaq?] y
@@ -1,5 +1,5 @@
1
2 2
3
-4
+4 4
5
record change 1/2 to '1.txt'? [Ynesfdaq?] y
diff --git a/dir/a.txt b/dir/a.txt
1 hunks, 1 lines changed
examine changes to 'dir/a.txt'? [Ynesfdaq?] y
@@ -1,4 +1,4 @@
-hello world
+hello world!
someone
up
record change 2/2 to 'dir/a.txt'? [Ynesfdaq?] y
After final qrefresh 'tip'
$ hg tip -p
changeset: 1:2c3f66afeed9
tag: patch
tag: qbase
tag: qtip
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: [mq]: patch
diff -r 1fd39ab63a33 -r 2c3f66afeed9 1.txt
--- a/1.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/1.txt Thu Jan 01 00:00:00 1970 +0000
@@ -1,5 +1,5 @@
1
-2
+2 2
3
-4
+4 4
5
diff -r 1fd39ab63a33 -r 2c3f66afeed9 2.txt
--- a/2.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/2.txt Thu Jan 01 00:00:00 1970 +0000
@@ -1,5 +1,5 @@
a
-b
+b b
c
d
e
diff -r 1fd39ab63a33 -r 2c3f66afeed9 dir/a.txt
--- a/dir/a.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/dir/a.txt Thu Jan 01 00:00:00 1970 +0000
@@ -1,4 +1,4 @@
-hello world
+hello world!
someone
up
After qrefresh 'diff'
$ hg diff --nodates
$ cd ..