webmcp: a2c733535b8e framework/bin/mcp.lua

28 Loads, compiles and caches a Lua chunk. If the file does not exist, nil and an error string are returned. Otherwise the file is loaded, compiled, and cached. The cached value (i.e. the compiled function) is returned. An error is raised if the compilation was not successful.

30 --]]--

31 do

32 local cache = {}

33 function loadcached(filename)

34 local cached_func = cache[filename]

35 if cached_func then

36 return cached_func

37 end

38 local file, read_error = io.open(filename, "r")

39 if file then

40 local filedata = assert(file:read("*a"))

41 assert(file:close())

42 local func, compile_error = load(filedata, "=" .. filename, nil, _ENV)

43 if func then

44 cache[filename] = func

45 return func

46 end

47 error(compile_error, 0)

48 else

49 return nil, read_error

50 end

51 end

52 end

53 --//--

55 --[[--

56 WEBMCP_MODE

58 A constant set to "listen" in case of a network request, or set to "interactive" in case of interactive mode.

59 --]]--

60 -- check if interactive mode

61 if listen then -- defined by moonbridge

62 WEBMCP_MODE = "listen"

63 else

64 WEBMCP_MODE = "interactive"

65 end

66 --//--

68 --[[--

69 WEBMCP_CONFIG_NAMES

71 A list of the selected configuration names.

72 --]]--

73 -- configuration names are provided as 4th, 5th, etc. command line argument

74 WEBMCP_CONFIG_NAMES = {select(4, ...)}

75 --//--

77 --[[--

78 WEBMCP_FRAMEWORK_PATH

80 Directory of the WebMCP framework (always includes a trailing slash).

81 --]]--

82 -- set in mcp.lua

83 --//--

85 --[[--

86 WEBMCP_BASE_PATH

88 Base directory of the application (always includes a trailing slash).

89 --]]--

90 -- set in mcp.lua

91 --//--

93 --[[--

94 WEBMCP_APP_NAME

96 Application name (usually "main"). May be nil in case of interactive mode.

97 --]]--

98 -- set in mcp.lua

99 --//--

100

101 -- determine framework and bath path from command line arguments

102 -- or print usage synopsis (if applicable)

103 do

104 local arg1, arg2, arg3 = ...

105 local helpout

106 if

107 arg1 == "-h" or arg1 == "--help" or

108 arg2 == "-h" or arg2 == "--help" -- if first arg is provided by wrapper

109 then

110 helpout = io.stdout

111 elseif #WEBMCP_CONFIG_NAMES < 1 then

112 helpout = io.stderr

113 end

114 if helpout then

115 helpout:write("Usage: moonbridge [moonbr opts] -- <framework path>/bin/mcp.lua <framework path> <app base path> <app name> <config name> [<config name> ...]\n")

116 helpout:write(" or: lua -i [Lua opts] -- <framework path>/bin/mcp.lua <framework path> <app base path> <app name> <config name> [<config name> ...]\n")

117 if helpout == io.stderr then

118 return 1

119 else

120 return 0

121 end

122 end

123 local function append_trailing_slash(str)

124 return string.gsub(str, "([^/])$", function(last) return last .. "/" end)

125 end

126 WEBMCP_FRAMEWORK_PATH = append_trailing_slash(arg1)

127 WEBMCP_BASE_PATH = append_trailing_slash(arg2)

128 WEBMCP_APP_NAME = arg3

129 end

130

131 -- check if framework path is correct

132 do

133 local file, errmsg = io.open(WEBMCP_FRAMEWORK_PATH .. "webmcp_version", "r")

134 if not file then

135 error('Could not find "webmcp_version" file: ' .. errmsg, 0)

136 end

137 local version = assert(file:read())

138 assert(file:close())

139 if version ~= WEBMCP_VERSION then

140 error('Version mismatch in file "' .. WEBMCP_FRAMEWORK_PATH .. 'webmcp_version"')

141 end

142 end

143

144 -- setup search paths for libraries

145 do

146 if string.match(package.path, "^[^;]") then

147 package.path = ";" .. package.path

148 end

149 package.path = WEBMCP_FRAMEWORK_PATH .. "lib/?.lua" .. package.path

150 -- find out which file name extension shared libraries have

151 local slib_exts = {}

152 for ext in string.gmatch(package.cpath, "%?%.([A-Za-z0-9_-]+)") do

153 if not slib_exts[ext] then

154 slib_exts[#slib_exts+1] = ext

155 slib_exts[ext] = true

156 end

157 end

158 local paths = {}

159 for i, ext in ipairs(slib_exts) do

160 paths[#paths+1] = WEBMCP_FRAMEWORK_PATH .. "accelerator/?." .. ext

161 end

162 for i, ext in ipairs(slib_exts) do

163 paths[#paths+1] = WEBMCP_FRAMEWORK_PATH .. "lib/?." .. ext

164 end

165 paths[#paths+1] = package.cpath

166 package.cpath = table.concat(paths, ";")

167 end

168

169 -- autoloader system for WebMCP environment "$WEBMCP_FRAMEWORK_PATH/env/",

170 -- application environment extensions "$WEBMCP_BASE_PATH/env/"

171 -- and models "$WEBMCP_BASE_PATH/model/"

172 do

173 local weakkey_mt = { __mode = "k" }

174 local autoloader_category = setmetatable({}, weakkey_mt)

175 local autoloader_path = setmetatable({}, weakkey_mt)

176 local autoloader_mt = {}

177 local function install_autoloader(self, category, path_fragment)

178 autoloader_category[self] = category

179 autoloader_path[self] = path_fragment

180 setmetatable(self, autoloader_mt)

181 end

182 local function try_exec(filename)

183 local func = loadcached(filename)

184 if func then

185 func()

186 return true

187 else

188 return false

189 end

190 end

191 function autoloader_mt.__index(self, key)

192 local category, base_path, merge_base_path, file_key

193 local merge = false

194 if

195 string.find(key, "^[a-z_][A-Za-z0-9_]*$") and

196 not string.find(key, "^__")

197 then

198 category = "env"

199 base_path = WEBMCP_FRAMEWORK_PATH .. "env/"

200 merge = true

201 merge_base_path = WEBMCP_BASE_PATH .. "env/"

202 file_key = key

203 elseif string.find(key, "^[A-Z][A-Za-z0-9]*$") then

204 category = "model"

205 base_path = WEBMCP_BASE_PATH .. "model/"

206 local first = true

207 file_key = string.gsub(key, "[A-Z]",

208 function(c)

209 if first then

210 first = false

211 return string.lower(c)

212 else

213 return "_" .. string.lower(c)

214 end

215 end

216 )

217 else

218 return

219 end

220 local required_category = autoloader_category[self]

221 if required_category and required_category ~= category then return end

222 local path_fragment = autoloader_path[self]

223 local path = base_path .. path_fragment .. file_key

224 local merge_path

225 if merge then

226 merge_path = merge_base_path .. path_fragment .. file_key

227 end

228 local function try_dir(dirname)

229 local dir = io.open(dirname)

230 if dir then

231 io.close(dir)

232 local obj = {}

233 install_autoloader(obj, category, path_fragment .. file_key .. "/")

234 rawset(self, key, obj)

235 try_exec(path .. "/__init.lua")

236 if merge then try_exec(merge_path .. "/__init.lua") end

237 return true

238 else

239 return false

240 end

241 end

242 if self == _G then

243 allowed_globals[key] = true

244 end

245 if merge and try_exec(merge_path .. ".lua") then

246 elseif merge and try_dir(merge_path .. "/") then

247 elseif try_exec(path .. ".lua") then

248 elseif try_dir(path .. "/") then

249 else end

250 if self == _G then

251 allowed_globals[key] = nil

252 end

253 return rawget(self, key)

254 end

255 install_autoloader(_G, nil, "")

256 try_exec(WEBMCP_FRAMEWORK_PATH .. "env/__init.lua")

257 try_exec(WEBMCP_BASE_PATH .. "env/__init.lua")

258 end

259

260 -- replace Moonbridge listen function

261 local moonbridge_listen = listen

262 local listeners = {}

263 function listen(args)

264 listeners[#listeners+1] = args

265 end

266

267 -- prohibit (unintended) definition of new global variables

268 function global_metatable.__newindex(self, key, value)

269 if not allowed_globals[key] then

270 error("Setting of global variable prohibited", 2)

271 end

272 _G[key] = value

273 end

274

275 -- execute configurations and pre-fork initializers

276 for i, config_name in ipairs(WEBMCP_CONFIG_NAMES) do

277 execute.config(config_name)

278 end

279 execute.prefork_initializers()

280

281 -- define post-fork initialization function (including loading of "multirand" library)

282 local function postfork_init()

283 _G.multirand = require "multirand"

284 execute.postfork_initializers()

285 end

286

287 -- interactive console mode

288 if WEBMCP_MODE == "interactive" then

289 postfork_init()

290 trace.disable() -- avoids memory leakage

291 end

292

293 -- invoke moonbridge

294 if WEBMCP_MODE == "listen" then

295 local http_options = request.get_http_options()

296 local min_requests_per_fork = http_options.min_requests_per_fork or 50

297 local max_requests_per_fork = http_options.max_requests_per_fork or 100

298 local http = require("moonbridge_http")

299 for i, listener in ipairs(listeners) do

300 local interval_handlers = {}

301 for j, entry in ipairs(listener) do

302 if entry.proto == "interval" then

303 local name = entry.name or "Unnamed interval #" .. #interval_handlers+1

304 interval_handlers[name] = entry.handler

305 entry.name = name

306 end

307 end

308 local request_count = 0

309 local function inner_handler(http_request)

310 request.handler(http_request, request_count >= max_requests_per_fork)

311 end

312 local outer_handler = http.generate_handler(inner_handler, http_options)

313 listener.prepare = postfork_init

314 listener.connect = function(socket)

315 request_count = request_count + 1

316 request.initialize()

317 if socket.interval then

318 interval_handlers[socket.interval]()

319 else

320 outer_handler(socket)

321 end

322 return request_count < min_requests_per_fork

323 end

324 listener.finish = execute.finalizers

325 moonbridge_listen(listener)

326 end

327 end