patch 7.4.1191
Problem: The channel feature isn't working yet.
Solution: Add the connect(), disconnect(), sendexpr() and sendraw()
functions. Add initial documentation. Add a demo server.
diff --git a/runtime/doc/Makefile b/runtime/doc/Makefile
index dc49bb7..6bbcbc3 100644
--- a/runtime/doc/Makefile
+++ b/runtime/doc/Makefile
@@ -17,6 +17,7 @@
arabic.txt \
autocmd.txt \
change.txt \
+ channel.txt \
cmdline.txt \
debug.txt \
debugger.txt \
@@ -151,6 +152,7 @@
arabic.html \
autocmd.html \
change.html \
+ channel.html \
cmdline.html \
debug.html \
debugger.html \
diff --git a/runtime/doc/channel.txt b/runtime/doc/channel.txt
new file mode 100644
index 0000000..21ce4eb
--- /dev/null
+++ b/runtime/doc/channel.txt
@@ -0,0 +1,218 @@
+*channel.txt* For Vim version 7.4. Last change: 2016 Jan 28
+
+
+ VIM REFERENCE MANUAL by Bram Moolenaar
+
+
+ Inter-process communication *channel*
+
+DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT DRAFT
+
+Vim uses channels to communicate with other processes.
+A channel uses a socket. *socket-interface*
+
+Vim current supports up to 10 simultanious channels.
+The Netbeans interface also uses a channel. |netbeans|
+
+1. Demo |channel-demo|
+2. Opening a channel |channel-open|
+3. Using a JSON channel |channel-use|
+4. Vim commands |channel-commands|
+5. Using a raw channel |channel-use|
+6. Job control |job-control|
+
+{Vi does not have any of these features}
+{only available when compiled with the |+channel| feature}
+
+==============================================================================
+1. Demo *channel-demo*
+
+This requires Python. The demo program can be found in
+$VIMRUNTIME/tools/demoserver.py
+Run it in one terminal. We will call this T1.
+
+Run Vim in another terminal. Connect to the demo server with: >
+ let handle = connect('localhost:8765', 'json')
+
+In T1 you should see:
+ === socket opened === ~
+
+You can now send a message to the server: >
+ echo sendexpr(handle, 'hello!')
+
+The message is received in T1 and a response is sent back to Vim.
+You can see the raw messages in T1. What Vim sends is:
+ [1,"hello!"] ~
+And the response is:
+ [1,"got it"] ~
+The number will increase every time you send a message.
+
+The server can send a command to Vim. Type this on T1 (literally, including
+the quotes): >
+ NOT IMPLEMENTED YET
+ ["ex","echo 'hi there'"]
+And you should see the message in Vim.
+
+To handle asynchronous communication a callback needs to be used: >
+ func MyHandler(handle, msg)
+ echo "from the handler: " . a:msg
+ endfunc
+ call sendexpr(handle, 'hello!', "MyHandler")
+
+Instead of giving a callback with every send call, it can also be specified
+when opening the channel: >
+ call disconnect(handle)
+ let handle = connect('localhost:8765', 'json', "MyHandler")
+ call sendexpr(handle, 'hello!', 0)
+
+==============================================================================
+2. Opening a channel *channel-open*
+
+To open a channel:
+ let handle = connect({address}, {mode}, {callback})
+
+{address} has the form "hostname:port". E.g., "localhost:8765".
+
+{mode} can be: *channel-mode*
+ "json" - Use JSON, see below; most convenient way
+ "raw" - Use raw messages
+
+ *channel-callback*
+{callback} is a function that is called when a message is received that is not
+handled otherwise. It gets two arguments: the channel handle and the received
+message. Example: >
+ func Handle(handle, msg)
+ echo 'Received: ' . a:msg
+ endfunc
+ let handle = connect("localhost:8765", 'json', "Handle")
+
+When {mode} is "json" the "msg" argument is the body of the received message,
+converted to Vim types.
+When {mode} is "raw" the "msg" argument is the whole message as a string.
+
+When {mode} is "json" the {callback} is optional. When omitted it is only
+possible to receive a message after sending one.
+
+The handler can be added or changed later: >
+ call sethandler(handle, {callback})
+When {callback} is empty (zero or an empty string) the handler is removed.
+
+Once done with the channel, disconnect it like this: >
+ call disconnect(handle)
+
+==============================================================================
+3. Using a JSON channel *channel-use*
+
+If {mode} is "json" then a message can be sent synchronously like this: >
+ let response = sendexpr(handle, {expr})
+This awaits a response from the other side.
+
+To send a message, without handling a response: >
+ call sendexpr(handle, {expr}, 0)
+
+To send a message and letting the response handled by a specific function,
+asynchronously: >
+ call sendexpr(handle, {expr}, {callback})
+
+The {expr} is converted to JSON and wrapped in an array. An example of the
+message that the receiver will get when {expr} is the string "hello":
+ [12,"hello"] ~
+
+The format of the JSON sent is:
+ [{number},{expr}]
+
+In which {number} is different every time. It must be used in the response
+(if any):
+
+ [{number},{response}]
+
+This way Vim knows which sent message matches with which received message and
+can call the right handler. Also when the messages arrive out of order.
+
+The sender must always send valid JSON to Vim. Vim can check for the end of
+the message by parsing the JSON. It will only accept the message if the end
+was received.
+
+When the process wants to send a message to Vim without first receiving a
+message, it must use the number zero:
+ [0,{response}]
+
+Then channel handler will then get {response} converted to Vim types. If the
+channel does not have a handler the message is dropped.
+
+On read error or disconnect() the string "DETACH" is sent, if still possible.
+The channel will then be inactive.
+
+==============================================================================
+4. Vim commands *channel-commands*
+
+NOT IMPLEMENTED YET
+
+With a "json" channel the process can send commands to Vim that will be
+handled by Vim internally, it does not require a handler for the channel.
+
+Possible commands are:
+ ["ex", {Ex command}]
+ ["normal", {Normal mode command}]
+ ["eval", {number}, {expression}]
+ ["expr", {expression}]
+
+With all of these: Be careful what these commands do! You can easily
+interfere with what the user is doing. To avoid trouble use |mode()| to check
+that the editor is in the expected state. E.g., to send keys that must be
+inserted as text, not executed as a command: >
+ ["ex","if mode() == 'i' | call feedkeys('ClassName') | endif"]
+
+The "ex" command is executed as any Ex command. There is no response for
+completion or error. You could use functions in an |autoload| script.
+You can also invoke |feedkeys()| to insert anything.
+
+The "normal" command is executed like with |:normal|.
+
+The "eval" command will result in sending back the result of the expression:
+ [{number}, {result}]
+Here {number} is the same as what was in the request.
+
+The "expr" command is similar, but does not send back any response.
+Example:
+ ["expr","setline('$', ['one', 'two', 'three'])"]
+
+==============================================================================
+5. Using a raw channel *channel-raw*
+
+If {mode} is "raw" then a message can be send like this: >
+ let response = sendraw(handle, {string})
+The {string} is sent as-is. The response will be what can be read from the
+channel right away. Since Vim doesn't know how to recognize the end of the
+message you need to take care of it yourself.
+
+To send a message, without expecting a response: >
+ call sendraw(handle, {string}, 0)
+The process can send back a response, the channel handler will be called with
+it.
+
+To send a message and letting the response handled by a specific function,
+asynchronously: >
+ call sendraw(handle, {string}, {callback})
+
+This {string} can also be JSON, use |jsonencode()| to create it and
+|jsondecode()| to handle a received JSON message.
+
+==============================================================================
+6. Job control *job-control*
+
+NOT IMPLEMENTED YET
+
+To start another process: >
+ call startjob({command})
+
+This does not wait for {command} to exit.
+
+TODO:
+
+ let handle = startjob({command}, 's') # uses stdin/stdout
+ let handle = startjob({command}, '', {address}) # uses socket
+ let handle = startjob({command}, 'd', {address}) # start if connect fails
+
+
+ vim:tw=78:ts=8:ft=help:norl:
diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt
index 4250319..959098a 100644
--- a/runtime/doc/eval.txt
+++ b/runtime/doc/eval.txt
@@ -1820,6 +1820,8 @@
complete_check() Number check for key typed during completion
confirm( {msg} [, {choices} [, {default} [, {type}]]])
Number number of choice picked by user
+connect( {address}, {mode} [, {callback}])
+ Number open a channel
copy( {expr}) any make a shallow copy of {expr}
cos( {expr}) Float cosine of {expr}
cosh( {expr}) Float hyperbolic cosine of {expr}
@@ -2027,6 +2029,10 @@
List search for other end of start/end pair
searchpos( {pattern} [, {flags} [, {stopline} [, {timeout}]]])
List search for {pattern}
+sendexpr( {handle}, {expr} [, {callback}])
+ any send {expr} over JSON channel {handle}
+sendraw( {handle}, {string} [, {callback}])
+ any send {string} over raw channel {handle}
server2client( {clientid}, {string})
Number send reply string
serverlist() String get a list of available servers
@@ -2660,6 +2666,18 @@
don't fit, a vertical layout is used anyway. For some systems
the horizontal layout is always used.
+connect({address}, {mode} [, {callback}]) *connect()*
+ Open a channel to {address}. See |channel|.
+
+ {address} has the form "hostname:port", e.g.,
+ "localhost:8765".
+
+ {mode} is either "json" or "raw". See |channel-mode| for the
+ meaning.
+
+ {callback} is a function that handles received messages on the
+ channel. See |channel-callback|.
+
*copy()*
copy({expr}) Make a copy of {expr}. For Numbers and Strings this isn't
different from using {expr} directly.
@@ -3861,7 +3879,9 @@
if filename =~ glob2regpat('Make*.mak')
< This is equivalent to: >
if filename =~ '^Make.*\.mak$'
-<
+< When {expr} is an empty string the result is "^$", match an
+ empty string.
+
*globpath()*
globpath({path}, {expr} [, {nosuf} [, {list} [, {allinks}]]])
Perform glob() on all directories in {path} and concatenate
@@ -5593,6 +5613,23 @@
< In this example "submatch" is 2 when a lowercase letter is
found |/\l|, 3 when an uppercase letter is found |/\u|.
+sendexpr({handle}, {expr} [, {callback}]) *sendexpr()*
+ Send {expr} over JSON channel {handle}. See |channel-use|.
+
+ When {callback} is given returns immediately. Without
+ {callback} waits for a JSON response and returns the decoded
+ expression. When there is an error or timeout returns an
+ empty string.
+
+ When {callback} is zero no response is expected.
+ Otherwise {callback} must be a Funcref or the name of a
+ function. It is called when the response is received. See
+ |channel-callback|.
+
+sendraw({handle}, {string} [, {callback}]) *sendraw()*
+ Send {string} over raw channel {handle}. See |channel-raw|.
+ Works like |sendexpr()|, but does not decode the response.
+
server2client( {clientid}, {string}) *server2client()*
Send a reply string to {clientid}. The most recent {clientid}
that sent a string can be retrieved with expand("<client>").
diff --git a/runtime/tools/demoserver.py b/runtime/tools/demoserver.py
new file mode 100644
index 0000000..c72a58b
--- /dev/null
+++ b/runtime/tools/demoserver.py
@@ -0,0 +1,87 @@
+#!/usr/bin/python
+# Server that will accept connections from a Vim channel.
+# Run this server and then in Vim you can open the channel:
+# :let handle = connect('localhost:8765', 'json')
+#
+# Then Vim can send requests to the server:
+# :let response = sendexpr(handle, 'hello!')
+#
+# And you can control Vim by typing a JSON message here, e.g.:
+# ["ex","echo 'hi there'"]
+#
+# See ":help channel-demo" in Vim.
+
+import SocketServer
+import json
+import socket
+import sys
+import threading
+
+thesocket = None
+
+class ThreadedTCPRequestHandler(SocketServer.BaseRequestHandler):
+
+ def handle(self):
+ print "=== socket opened ==="
+ global thesocket
+ thesocket = self.request
+ while True:
+ try:
+ data = self.request.recv(4096)
+ except socket.error:
+ print "=== socket error ==="
+ break
+ except IOError:
+ print "=== socket closed ==="
+ break
+ if data == '':
+ print "=== socket closed ==="
+ break
+ print "received: {}".format(data)
+ try:
+ decoded = json.loads(data)
+ except ValueError:
+ print "json decoding failed"
+ decoded = [0, '']
+
+ if decoded[1] == 'hello!':
+ response = "got it"
+ else:
+ response = "what?"
+ encoded = json.dumps([decoded[0], response])
+ print "sending {}".format(encoded)
+ self.request.sendall(encoded)
+ thesocket = None
+
+class ThreadedTCPServer(SocketServer.ThreadingMixIn, SocketServer.TCPServer):
+ pass
+
+if __name__ == "__main__":
+ HOST, PORT = "localhost", 8765
+
+ server = ThreadedTCPServer((HOST, PORT), ThreadedTCPRequestHandler)
+ ip, port = server.server_address
+
+ # Start a thread with the server -- that thread will then start one
+ # more thread for each request
+ server_thread = threading.Thread(target=server.serve_forever)
+
+ # Exit the server thread when the main thread terminates
+ server_thread.daemon = True
+ server_thread.start()
+ print "Server loop running in thread: ", server_thread.name
+
+ print "Listening on port {}".format(PORT)
+ while True:
+ typed = sys.stdin.readline()
+ if "quit" in typed:
+ print "Goodbye!"
+ break
+ if thesocket is None:
+ print "No socket yet"
+ else:
+ print "sending {}".format(typed)
+ thesocket.sendall(typed)
+
+ server.shutdown()
+ server.server_close()