[tarantool-patches] [RFC] box/lua/console: Add console.fmt module
Cyrill Gorcunov
gorcunov at gmail.com
Fri Jun 21 00:54:05 MSK 2019
The rationale of the module is to provide a way to configure
console output format, in particular one might need to copy
results of eval and paste it into some other command. To
switch console into that named lua mode one need to type
> require('console.fmt').set_format('lua')
To set it back to yaml mode just type
> require('console.fmt').set_format('yaml')
At the moment these two modes are supprted only.
Some details on internal structure: general console code
sits in src/box/lua/[console.c|console.lua] files; the C file
is resposible for readline library api and yaml serializer.
In turn the "formatter" now moved into src/box/lua/console_fmt.lua
and coupled with general console code. General console code simply
calls for formatter and provides output depending on active engine
(by default we continue use yaml backend in a sake of backward
compatibility).
There is at least one explicit problem remains: console text protocol
(console.lua:wrap_text_socket()) it waits the other peer to reply in
yaml format and tries to decode it. According to repo history the text
protocol is deprecated by now so I think we might safely remove the
code completely.
Please review carefully, any comments/complains are highly appreciated.
Of course I will need to provide some more test but first would like
to hear early feedback on the code design.
https://github.com/tarantool/tarantool/issues/3834
---
src/box/CMakeLists.txt | 1 +
src/box/lua/console.lua | 41 ++---
src/box/lua/console_fmt.lua | 295 ++++++++++++++++++++++++++++++++++++
src/box/lua/init.c | 2 +
4 files changed, 309 insertions(+), 30 deletions(-)
create mode 100644 src/box/lua/console_fmt.lua
diff --git a/src/box/CMakeLists.txt b/src/box/CMakeLists.txt
index 481842a39..2f7e90e5e 100644
--- a/src/box/CMakeLists.txt
+++ b/src/box/CMakeLists.txt
@@ -11,6 +11,7 @@ lua_source(lua_sources lua/feedback_daemon.lua)
lua_source(lua_sources lua/net_box.lua)
lua_source(lua_sources lua/upgrade.lua)
lua_source(lua_sources lua/console.lua)
+lua_source(lua_sources lua/console_fmt.lua)
lua_source(lua_sources lua/xlog.lua)
lua_source(lua_sources lua/key_def.lua)
lua_source(lua_sources lua/merger.lua)
diff --git a/src/box/lua/console.lua b/src/box/lua/console.lua
index f922f0320..9298ad44b 100644
--- a/src/box/lua/console.lua
+++ b/src/box/lua/console.lua
@@ -1,6 +1,7 @@
-- console.lua -- internal file
local internal = require('console')
+local cfmt = require('console.fmt')
local session_internal = require('box.internal.session')
local fiber = require('fiber')
local socket = require('socket')
@@ -13,26 +14,6 @@ local net_box = require('net.box')
local YAML_TERM = '\n...\n'
local PUSH_TAG_HANDLE = '!push!'
-local function format(status, ...)
- local err
- if status then
- -- serializer can raise an exception
- status, err = pcall(internal.format, ...)
- if status then
- return err
- else
- err = 'console: an exception occurred when formatting the output: '..
- tostring(err)
- end
- else
- err = ...
- if err == nil then
- err = box.NULL
- end
- end
- return internal.format({ error = err })
-end
-
--
-- Set delimiter
--
@@ -81,16 +62,16 @@ local function set_param(storage, func, param, value)
d = set_delimiter
}
if param == nil then
- return format(false, 'Invalid set syntax, type \\help for help')
+ return cfmt.format(false, 'Invalid set syntax, type \\help for help')
end
if params[param] == nil then
- return format(false, 'Unknown parameter: ' .. tostring(param))
+ return cfmt.format(false, 'Unknown parameter: ' .. tostring(param))
end
- return format(pcall(params[param], storage, value))
+ return cfmt.format(pcall(params[param], storage, value))
end
local function help_wrapper(storage)
- return format(true, help()) -- defined in help.lua
+ return cfmt.format(true, help()) -- defined in help.lua
end
local function quit(storage)
@@ -119,7 +100,7 @@ local function preprocess(storage, line)
end
if operators[items[1]] == nil then
local msg = "Invalid command \\%s. Type \\help for help."
- return format(false, msg:format(items[1]))
+ return cfmt.format(false, msg:format(items[1]))
end
return operators[items[1]](storage, unpack(items))
end
@@ -135,7 +116,7 @@ local function local_eval(storage, line)
return preprocess(storage, line:sub(2))
end
if storage.language == 'sql' then
- return format(pcall(box.execute, line))
+ return cfmt.format(pcall(box.execute, line))
end
--
-- Attempt to append 'return ' before the chunk: if the chunk is
@@ -148,9 +129,9 @@ local function local_eval(storage, line)
fun, errmsg = loadstring(line)
end
if not fun then
- return format(false, errmsg)
+ return cfmt.format(false, errmsg)
end
- return format(pcall(fun))
+ return cfmt.format(pcall(fun))
end
local function eval(line)
@@ -258,7 +239,7 @@ local function remote_eval(self, line)
if line and self.remote.state == 'active' then
local ok, res = pcall(self.remote.eval, self.remote, line)
if self.remote.state == 'active' then
- return ok and res or format(false, res)
+ return ok and res or cfmt.format(false, res)
end
end
local err = self.remote.error
@@ -268,7 +249,7 @@ local function remote_eval(self, line)
self.prompt = nil
self.completion = nil
pcall(self.on_client_disconnect, self)
- return (err and format(false, err)) or ''
+ return (err and cfmt.format(false, err)) or ''
end
local function local_check_lua(buf)
diff --git a/src/box/lua/console_fmt.lua b/src/box/lua/console_fmt.lua
new file mode 100644
index 000000000..f860d76fb
--- /dev/null
+++ b/src/box/lua/console_fmt.lua
@@ -0,0 +1,295 @@
+-- # vim: ts=4 sw=4 et
+
+local internal = require('console')
+
+local console_formats = {
+ ["lua"] = nil,
+ ["yaml"] = nil
+}
+
+---
+--- Serializer in Lua syntax, which represent data
+--- in a format suitable for Lua REPL.
+---
+
+local lua_keyword = {
+ ["and"] = true, ["break"] = true, ["do"] = true,
+ ["else"] = true, ["elseif"] = true, ["end"] = true,
+ ["false"] = true, ["for"] = true, ["function"] = true,
+ ["if"] = true, ["in"] = true, ["local"] = true,
+ ["nil"] = true, ["not"] = true, ["or"] = true,
+ ["repeat"] = true, ["return"] = true, ["then"] = true,
+ ["true"] = true, ["until"] = true, ["while"] = true
+}
+
+local function has_lquote(s)
+ local lstring_pat = '([%[%]])(=*)%1'
+ local equals, new_equals, _
+ local finish = 1
+ repeat
+ _, finish, _, new_equals = s:find(lstring_pat, finish)
+ if new_equals then
+ equals = math.max(equals or 0, #new_equals)
+ end
+ until not new_equals
+
+ return equals
+end
+
+local function is_identifier(s)
+ return type(s) == 'string' and s:find('^[%a_][%w_]*$') and not lua_keyword[s]
+end
+
+local function quote_string(s)
+ if type(s) ~= 'string' then
+ error("quote_string: s should be a string")
+ end
+
+ -- Find out if there are any embedded long-quote sequences that may cause issues.
+ -- This is important when strings are embedded within strings, like when serializing.
+ -- Append a closing bracket to catch unfinished long-quote sequences at the end of the string.
+ local equal_signs = has_lquote(s .. "]")
+
+ -- Note that strings containing "\r" can't be quoted using long brackets
+ -- as Lua lexer converts all newlines to "\n" within long strings.
+ if (s:find("\n") or equal_signs) and not s:find("\r") then
+ -- If there is an embedded sequence that matches a long quote, then
+ -- find the one with the maximum number of = signs and add one to that number.
+ equal_signs = ("="):rep((equal_signs or -1) + 1)
+ -- Long strings strip out leading newline. We want to retain that, when quoting.
+ if s:find("^\n") then s = "\n" .. s end
+ local lbracket, rbracket =
+ "[" .. equal_signs .. "[",
+ "]" .. equal_signs .. "]"
+ s = lbracket .. s .. rbracket
+ else
+ -- Escape funny stuff. Lua 5.1 does not handle "\r" correctly.
+ s = ("%q"):format(s):gsub("\r", "\\r")
+ end
+ return s
+end
+
+local function quote_if_necessary(v)
+ if not v then
+ return ''
+ else
+ if v:find ' ' then
+ v = quote_string(v)
+ end
+ end
+ return v
+end
+
+local function quote(s)
+ if type(s) == 'table' then
+ return console_formats["lua"](s, '')
+ else
+ return quote_string(s)
+ end
+end
+
+local function index(numkey, key)
+ if not numkey then
+ key = quote(key)
+ key = key:find("^%[") and (" " .. key .. " ") or key
+ end
+ return '[' .. key .. ']'
+end
+
+--- Create a string representation of a Lua table.
+--
+-- This function never fails, but may complain by returning an
+-- extra value. Normally puts out one item per line, using
+-- the provided indent; set the second parameter to an empty string
+-- if you want output on one line.
+--
+-- @tab tbl Table to serialize to a string.
+-- @string[opt] space The indent to use.
+-- Defaults to two spaces; pass an empty string for no indentation.
+-- @bool[opt] not_clever Pass `true` for plain output, e.g `{['key']=1}`.
+-- Defaults to `false`.
+--
+-- @return a string
+console_formats["lua"] = function(tbl, space, not_clever)
+ if type(tbl) ~= 'table' then
+ if type(tbl) == 'string' then
+ return quote(tbl)
+ end
+ return tostring(tbl)
+ end
+
+ local set = ' = '
+ if space == '' then set = '=' end
+ space = space or ' '
+ local lines = {}
+ local line = ''
+ local tables = {}
+
+ local function put(s)
+ if #s > 0 then
+ line = line .. s
+ end
+ end
+
+ local function putln(s)
+ if #line > 0 then
+ line = line .. s
+ table.insert(lines, line)
+ line = ''
+ else
+ table.insert(lines, s)
+ end
+ end
+
+ local function eat_last_comma()
+ local n = #lines
+ local lastch = lines[n]:sub(-1,-1)
+ if lastch == ',' then
+ lines[n] = lines[n]:sub(1,-2)
+ end
+ end
+
+ local function preprocess(t)
+ local specials = {
+ [box.NULL] = 'box.NULL'
+ }
+ if specials[t] then
+ return true, specials[t]
+ end
+ return false, nil
+ end
+
+ local function writeit(t, oldindent, indent)
+ local pp, pps = preprocess(t)
+ local tp = type(t)
+ if pp then
+ putln(pps .. ',')
+ elseif tp ~= 'string' and tp ~= 'table' then
+ putln(quote_if_necessary(tostring(t)) .. ',')
+ elseif tp == 'string' then
+ putln(quote_string(t) .. ',')
+ elseif tp == 'table' then
+ if tables[t] then
+ putln('<cycle>,')
+ return
+ end
+
+ tables[t] = true
+ local newindent = indent .. space
+ putln('{')
+ local used = {}
+ if not not_clever then
+ for i,val in ipairs(t) do
+ put(indent)
+ writeit(val, indent, newindent)
+ used[i] = true
+ end
+ end
+ for key,val in pairs(t) do
+ local tkey = type(key)
+ local numkey = tkey == 'number'
+ if not_clever then
+ key = tostring(key)
+ put(indent .. index(numkey, key) .. set)
+ writeit(val, indent, newindent)
+ else
+ if not numkey or not used[key] then -- non-array indices
+ if tkey ~= 'string' then
+ key = tostring(key)
+ end
+ if numkey or not is_identifier(key) then
+ key = index(numkey, key)
+ end
+ put(indent .. key .. set)
+ writeit(val, indent, newindent)
+ end
+ end
+ end
+ tables[t] = nil
+ eat_last_comma()
+ putln(oldindent .. '},')
+ else
+ putln(tostring(t) .. ',')
+ end
+ end
+ writeit(tbl, '', space)
+ eat_last_comma()
+ return table.concat(lines, #space > 0 and '\n' or '')
+end
+
+---
+--- Serializer in YAML format, basically we call for
+--- external serializer which lives in C code.
+---
+
+console_formats["yaml"] = function(status, ...)
+ local err
+ if status then
+ -- serializer can raise an exception
+ status, err = pcall(internal.format, ...)
+ if status then
+ return err
+ else
+ err = 'console.fmt: an exception in output ' .. tostring(err)
+ end
+ else
+ err = ...
+ if err == nil then
+ err = box.NULL
+ end
+ return internal.format({ error = err })
+ end
+end
+
+--
+-- Default console format
+--
+console_format = console_formats["yaml"]
+
+---
+--- Package API
+---
+
+--
+-- Setup requested format
+local function set_format(name)
+ if console_formats[name] ~= nil then
+ console_format = console_formats[name]
+ else
+ error(string.format("console.fmt: Unsupported console format %s", name))
+ end
+end
+
+--
+-- Report currently used format
+local function get_format()
+ for k,v in pairs(console_formats) do
+ if console_format == v then
+ return k
+ end
+ end
+end
+
+--
+-- Main message formatter, choose a proper
+-- format engine and pass arguments into.
+local function format(status, ...)
+ if console_format == console_formats["lua"] then
+ local data = ...
+ if data == nil then
+ -- In case if there is no data just
+ -- return empty string to not spam
+ -- with "nil" message.
+ return ""
+ end
+ return console_format(..., '')
+ end
+ return console_format(status, ...)
+end
+
+package.loaded['console.fmt'] = {
+ formats_map = console_formats,
+ set_format = set_format,
+ get_format = get_format,
+ format = format
+}
diff --git a/src/box/lua/init.c b/src/box/lua/init.c
index 76b987b4b..aff84c87a 100644
--- a/src/box/lua/init.c
+++ b/src/box/lua/init.c
@@ -71,6 +71,7 @@ extern char session_lua[],
feedback_daemon_lua[],
net_box_lua[],
upgrade_lua[],
+ console_fmt_lua[],
console_lua[],
merger_lua[];
@@ -81,6 +82,7 @@ static const char *lua_sources[] = {
"box/feedback_daemon", feedback_daemon_lua,
"box/upgrade", upgrade_lua,
"box/net_box", net_box_lua,
+ "box/console_fmt", console_fmt_lua,
"box/console", console_lua,
"box/load_cfg", load_cfg_lua,
"box/xlog", xlog_lua,
--
2.20.1
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