wireproto: define and use types for wire protocol commands
Wire protocol commands have historically been declared as
2-tuples in wireproto.commands. There are some additional features I'd
like to implement that require going beyond 2-tuples. But because
the 2-tuple API (both destructuring assignment and direct assignment
into the dict) is used throughout the code base and in 3rd party
extensions, we can't do a trivial type change.
This commit creates a new "commandentry" type to represent declared
wire protocol commands. It implements __getitem__ and __iter__ so
it can quack like a 2-tuple. The @wireprotocommand decorator now
creates "commandentry" instances.
We also create a "commanddict" type to represent the dictionary of
declared wire protocol commands. It inherits from "dict" but provides
a custom __setitem__ to coerce passed 2-tuples to "commandentry"
instances. wireproto.commands is now an instance of this type.
Various callers in core rely on the new functionality. And tests
pass. So I'm reasonably confident things will "just work" in 3rd
party extensions as well.
Differential Revision: https://phab.mercurial-scm.org/D1998
$ cat >> $HGRCPATH << EOF
> [web]
> push_ssl = false
> allow_push = *
> EOF
$ hg init server
$ cd server
$ touch a
$ hg -q commit -A -m initial
$ cd ..
$ hg serve -R server -p $HGPORT -d --pid-file hg.pid
$ cat hg.pid >> $DAEMON_PIDS
compression formats are advertised in compression capability
#if zstd
$ get-with-headers.py $LOCALIP:$HGPORT '?cmd=capabilities' | tr ' ' '\n' | grep '^compression=zstd,zlib$' > /dev/null
#else
$ get-with-headers.py $LOCALIP:$HGPORT '?cmd=capabilities' | tr ' ' '\n' | grep '^compression=zlib$' > /dev/null
#endif
$ killdaemons.py
server.compressionengines can replace engines list wholesale
$ hg serve --config server.compressionengines=none -R server -p $HGPORT -d --pid-file hg.pid
$ cat hg.pid > $DAEMON_PIDS
$ get-with-headers.py $LOCALIP:$HGPORT '?cmd=capabilities' | tr ' ' '\n' | grep '^compression=none$' > /dev/null
$ killdaemons.py
Order of engines can also change
$ hg serve --config server.compressionengines=none,zlib -R server -p $HGPORT -d --pid-file hg.pid
$ cat hg.pid > $DAEMON_PIDS
$ get-with-headers.py $LOCALIP:$HGPORT '?cmd=capabilities' | tr ' ' '\n' | grep '^compression=none,zlib$' > /dev/null
$ killdaemons.py
Start a default server again
$ hg serve -R server -p $HGPORT -d --pid-file hg.pid
$ cat hg.pid > $DAEMON_PIDS
Server should send application/mercurial-0.1 to clients if no Accept is used
$ get-with-headers.py --headeronly $LOCALIP:$HGPORT '?cmd=getbundle&heads=e93700bd72895c5addab234c56d4024b487a362f&common=0000000000000000000000000000000000000000' -
200 Script output follows
content-type: application/mercurial-0.1
date: * (glob)
server: * (glob)
transfer-encoding: chunked
Server should send application/mercurial-0.1 when client says it wants it
$ get-with-headers.py --hgproto '0.1' --headeronly $LOCALIP:$HGPORT '?cmd=getbundle&heads=e93700bd72895c5addab234c56d4024b487a362f&common=0000000000000000000000000000000000000000' -
200 Script output follows
content-type: application/mercurial-0.1
date: * (glob)
server: * (glob)
transfer-encoding: chunked
Server should send application/mercurial-0.2 when client says it wants it
$ get-with-headers.py --hgproto '0.2' --headeronly $LOCALIP:$HGPORT '?cmd=getbundle&heads=e93700bd72895c5addab234c56d4024b487a362f&common=0000000000000000000000000000000000000000' -
200 Script output follows
content-type: application/mercurial-0.2
date: * (glob)
server: * (glob)
transfer-encoding: chunked
$ get-with-headers.py --hgproto '0.1 0.2' --headeronly $LOCALIP:$HGPORT '?cmd=getbundle&heads=e93700bd72895c5addab234c56d4024b487a362f&common=0000000000000000000000000000000000000000' -
200 Script output follows
content-type: application/mercurial-0.2
date: * (glob)
server: * (glob)
transfer-encoding: chunked
Requesting a compression format that server doesn't support results will fall back to 0.1
$ get-with-headers.py --hgproto '0.2 comp=aa' --headeronly $LOCALIP:$HGPORT '?cmd=getbundle&heads=e93700bd72895c5addab234c56d4024b487a362f&common=0000000000000000000000000000000000000000' -
200 Script output follows
content-type: application/mercurial-0.1
date: * (glob)
server: * (glob)
transfer-encoding: chunked
#if zstd
zstd is used if available
$ get-with-headers.py --hgproto '0.2 comp=zstd' $LOCALIP:$HGPORT '?cmd=getbundle&heads=e93700bd72895c5addab234c56d4024b487a362f&common=0000000000000000000000000000000000000000' > resp
$ f --size --hexdump --bytes 36 --sha1 resp
resp: size=248, sha1=4d8d8f87fb82bd542ce52881fdc94f850748
0000: 32 30 30 20 53 63 72 69 70 74 20 6f 75 74 70 75 |200 Script outpu|
0010: 74 20 66 6f 6c 6c 6f 77 73 0a 0a 04 7a 73 74 64 |t follows...zstd|
0020: 28 b5 2f fd |(./.|
#endif
application/mercurial-0.2 is not yet used on non-streaming responses
$ get-with-headers.py --hgproto '0.2' $LOCALIP:$HGPORT '?cmd=heads' -
200 Script output follows
content-length: 41
content-type: application/mercurial-0.1
date: * (glob)
server: * (glob)
e93700bd72895c5addab234c56d4024b487a362f
Now test protocol preference usage
$ killdaemons.py
$ hg serve --config server.compressionengines=none,zlib -R server -p $HGPORT -d --pid-file hg.pid
$ cat hg.pid > $DAEMON_PIDS
No Accept will send 0.1+zlib, even though "none" is preferred b/c "none" isn't supported on 0.1
$ get-with-headers.py --headeronly $LOCALIP:$HGPORT '?cmd=getbundle&heads=e93700bd72895c5addab234c56d4024b487a362f&common=0000000000000000000000000000000000000000' Content-Type
200 Script output follows
content-type: application/mercurial-0.1
$ get-with-headers.py $LOCALIP:$HGPORT '?cmd=getbundle&heads=e93700bd72895c5addab234c56d4024b487a362f&common=0000000000000000000000000000000000000000' > resp
$ f --size --hexdump --bytes 28 --sha1 resp
resp: size=227, sha1=35a4c074da74f32f5440da3cbf04
0000: 32 30 30 20 53 63 72 69 70 74 20 6f 75 74 70 75 |200 Script outpu|
0010: 74 20 66 6f 6c 6c 6f 77 73 0a 0a 78 |t follows..x|
Explicit 0.1 will send zlib because "none" isn't supported on 0.1
$ get-with-headers.py --hgproto '0.1' $LOCALIP:$HGPORT '?cmd=getbundle&heads=e93700bd72895c5addab234c56d4024b487a362f&common=0000000000000000000000000000000000000000' > resp
$ f --size --hexdump --bytes 28 --sha1 resp
resp: size=227, sha1=35a4c074da74f32f5440da3cbf04
0000: 32 30 30 20 53 63 72 69 70 74 20 6f 75 74 70 75 |200 Script outpu|
0010: 74 20 66 6f 6c 6c 6f 77 73 0a 0a 78 |t follows..x|
0.2 with no compression will get "none" because that is server's preference
(spec says ZL and UN are implicitly supported)
$ get-with-headers.py --hgproto '0.2' $LOCALIP:$HGPORT '?cmd=getbundle&heads=e93700bd72895c5addab234c56d4024b487a362f&common=0000000000000000000000000000000000000000' > resp
$ f --size --hexdump --bytes 32 --sha1 resp
resp: size=432, sha1=ac931b412ec185a02e0e5bcff98dac83
0000: 32 30 30 20 53 63 72 69 70 74 20 6f 75 74 70 75 |200 Script outpu|
0010: 74 20 66 6f 6c 6c 6f 77 73 0a 0a 04 6e 6f 6e 65 |t follows...none|
Client receives server preference even if local order doesn't match
$ get-with-headers.py --hgproto '0.2 comp=zlib,none' $LOCALIP:$HGPORT '?cmd=getbundle&heads=e93700bd72895c5addab234c56d4024b487a362f&common=0000000000000000000000000000000000000000' > resp
$ f --size --hexdump --bytes 32 --sha1 resp
resp: size=432, sha1=ac931b412ec185a02e0e5bcff98dac83
0000: 32 30 30 20 53 63 72 69 70 74 20 6f 75 74 70 75 |200 Script outpu|
0010: 74 20 66 6f 6c 6c 6f 77 73 0a 0a 04 6e 6f 6e 65 |t follows...none|
Client receives only supported format even if not server preferred format
$ get-with-headers.py --hgproto '0.2 comp=zlib' $LOCALIP:$HGPORT '?cmd=getbundle&heads=e93700bd72895c5addab234c56d4024b487a362f&common=0000000000000000000000000000000000000000' > resp
$ f --size --hexdump --bytes 33 --sha1 resp
resp: size=232, sha1=a1c727f0c9693ca15742a75c30419bc36
0000: 32 30 30 20 53 63 72 69 70 74 20 6f 75 74 70 75 |200 Script outpu|
0010: 74 20 66 6f 6c 6c 6f 77 73 0a 0a 04 7a 6c 69 62 |t follows...zlib|
0020: 78 |x|