webmcp: d34b7b5e5e5c 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

112 #WEBMCP_CONFIG_NAMES < 1 or

113 (WEBMCP_MODE == "interactive") ~= (arg3 == "INTERACTIVE")

114 then

115 helpout = io.stderr

116 end

117 if helpout then

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

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

120 if helpout == io.stderr then

121 return 1

122 else

123 return 0

124 end

125 end

126 local function append_trailing_slash(str)

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

128 end

129 WEBMCP_FRAMEWORK_PATH = append_trailing_slash(arg1)

130 WEBMCP_BASE_PATH = append_trailing_slash(arg2)

131 if WEBMCP_MODE == "listen" then

132 WEBMCP_APP_NAME = arg3

133 end

134 end

135

136 -- check if framework path is correct

137 do

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

139 if not file then

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

141 end

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

143 assert(file:close())

144 if version ~= WEBMCP_VERSION then

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

146 end

147 end

148

149 -- setup search paths for libraries

150 do

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

152 package.path = ";" .. package.path

153 end

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

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

156 local slib_exts = {}

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

158 if not slib_exts[ext] then

159 slib_exts[#slib_exts+1] = ext

160 slib_exts[ext] = true

161 end

162 end

163 local paths = {}

164 for i, ext in ipairs(slib_exts) do

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

166 end

167 for i, ext in ipairs(slib_exts) do

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

169 end

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

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

172 end

173

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

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

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

177 do

178 local weakkey_mt = { __mode = "k" }

179 local autoloader_category = setmetatable({}, weakkey_mt)

180 local autoloader_path = setmetatable({}, weakkey_mt)

181 local autoloader_mt = {}

182 local function install_autoloader(self, category, path_fragment)

183 autoloader_category[self] = category

184 autoloader_path[self] = path_fragment

185 setmetatable(self, autoloader_mt)

186 end

187 local function try_exec(filename)

188 local func = loadcached(filename)

189 if func then

190 func()

191 return true

192 else

193 return false

194 end

195 end

196 function autoloader_mt.__index(self, key)

197 local category, base_path, merge_base_path, file_key

198 local merge = false

199 if

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

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

202 then

203 category = "env"

204 base_path = WEBMCP_FRAMEWORK_PATH .. "env/"

205 merge = true

206 merge_base_path = WEBMCP_BASE_PATH .. "env/"

207 file_key = key

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

209 category = "model"

210 base_path = WEBMCP_BASE_PATH .. "model/"

211 local first = true

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

213 function(c)

214 if first then

215 first = false

216 return string.lower(c)

217 else

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

219 end

220 end

221 )

222 else

223 return

224 end

225 local required_category = autoloader_category[self]

226 if required_category and required_category ~= category then return end

227 local path_fragment = autoloader_path[self]

228 local path = base_path .. path_fragment .. file_key

229 local merge_path

230 if merge then

231 merge_path = merge_base_path .. path_fragment .. file_key

232 end

233 local function try_dir(dirname)

234 local dir = io.open(dirname)

235 if dir then

236 io.close(dir)

237 local obj = {}

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

239 rawset(self, key, obj)

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

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

242 return true

243 else

244 return false

245 end

246 end

247 if self == _G then

248 allowed_globals[key] = true

249 end

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

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

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

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

254 else end

255 if self == _G then

256 allowed_globals[key] = nil

257 end

258 return rawget(self, key)

259 end

260 install_autoloader(_G, nil, "")

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

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

263 end

264

265 -- replace Moonbridge listen function

266 local moonbridge_listen = listen

267 local listeners = {}

268 function listen(args)

269 listeners[#listeners+1] = args

270 end

271

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

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

274 if not allowed_globals[key] then

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

276 end

277 _G[key] = value

278 end

279

280 -- execute configurations and pre-fork initializers

281 for i, config_name in ipairs(WEBMCP_CONFIG_NAMES) do

282 execute.config(config_name)

283 end

284 execute.prefork_initializers()

285

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

287 local function postfork_init()

288 _G.multirand = require "multirand"

289 execute.postfork_initializers()

290 end

291

292 -- interactive console mode

293 if WEBMCP_MODE == "interactive" then

294 postfork_init()

295 trace.disable() -- avoids memory leakage

296 end

297

298 -- invoke moonbridge

299 if WEBMCP_MODE == "listen" then

300 local http_options = request.get_http_options()

301 local min_requests_per_fork = http_options.min_requests_per_fork or 50

302 local max_requests_per_fork = http_options.max_requests_per_fork or 100

303 local http = require("moonbridge_http")

304 for i, listener in ipairs(listeners) do

305 local request_count = 0

306 local function inner_handler(http_request)

307 request_count = request_count + 1

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

309 end

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

311 listener.prepare = postfork_init

312 listener.connect = function(socket)

313 outer_handler(socket)

314 return request_count < min_requests_per_fork

315 end

316 listener.finish = execute.finalizers

317 moonbridge_listen(listener)

318 end

319 end

320