application.lua

 
local application = {}

local safer = require("safer")

local client = require("sga.client")
local server = require("sga.server")

local logging = require("logging")
local copas = require("copas")
local lfs = require("lfs")
local schema = require("schema")

local function bold(text)
   return "\27[1m"..text.."\27[0m"
end

local function color(level)
   if level == "ERROR" then
      return "\27[1;31m"..level.."\27[0m"
   elseif level == "WARNING" then
      return "\27[1;33m"..level.."\27[0m"
   elseif level == "DEBUG" then
      return "\27[0;35m"..level.."\27[0m"
   elseif level == "INFO" then
      return "\27[0;36m"..level.."\27[0m"
   else
      return level
   end
end

local function make_logger(ident)
   return safer.readonly(logging.new(function(_, level, message)
      io.stderr:write(bold(os.date()).." ["..color(level).."] "..bold(ident)..": "..message.."\n") 
      return true
   end))
end

--[[

   Application architecture:

                  ┌──────────┐
         ┌───────◇│  client  │◇───────┐
         │        └────┬─────┘        │
         │             │              │
         │             ◇              │
   ┌─────┴────┐   ┌──────────┐   ┌────┴─────┐
   │  config  ├──◇│  server  │◇──┤  logger  │
   └─────┬────┘   └──────────┘   └────┬─────┘
         │             ◇   ◆          │
         │             │   │          │
         │             │ ┌─┴────────┐ │
         │             │ │ job list │ │
         │             │ └──────────┘ │
         │        ┌────┴─────┐        │
         └───────◇│  driver  │◇───────┘
                  └──────────┘

--]]
function application.new(config)
   local ok, err = lfs.mkdir(config.runtime_data_dir)
   if not ok then
      local attr = lfs.attributes(config.runtime_data_dir)
      if not (attr and attr.mode == "directory") then
         return nil, "Failed creating runtime data dir "..config.runtime_data_dir
      end
   end

   local client_object = client.new(config, make_logger("sga.client"))