update file_size after write

Readme.md

@@ -234,10 +234,10 @@ Notes
 Known Issues
 ---------------------------
 1. Auth bson message has reduntant value.
-2. Could not inserting a null array, it always inserted as a document.
-3. Gridfs_new api only create a meta info in file_col.
+2. Gridfs_new api only create a meta info in file_col.
 
-Example
+
+Basic Usage
 ---------------------------
             local mongo = require "resty.mongol"
             conn = mongo:new()
@@ -252,7 +252,11 @@ Example
 
             r = col:find_one({name="dog"})
             ngx.say(r["name"])
+
+
+See wiki for advanced examples
 
+
 For Test Case
 --------------------
 #####mongo config:

lib/resty/mongol/ObjectId.lua

@@ -0,0 +1,104 @@
+local type = type
+local require = require
+local assert = assert
+local setmetatable = setmetatable
+
+local string_byte = string.byte
+local string_format = string.format
+local table_insert = table.insert
+local table_concat = table.concat
+local os_time = os.time
+local io_popen = io.popen
+
+local hasposix, posix = pcall(require , "posix")
+
+local ngx = ngx
+local ngx_decode_base64 = ngx.decode_base64
+local ngx_encode_base64 = ngx.encode_base64
+local ngx_md5_bin = ngx.md5_bin
+
+module(...)
+
+local ll = require(_PACKAGE.."ll")
+local num_to_le_uint = ll.num_to_le_uint
+local num_to_be_uint = ll.num_to_be_uint
+local be_uint_tonum = ll.be_uint_to_num
+
+local machineid
+local function _get_os_machineid()
+  if hasposix then
+    machineid = posix.uname("%n")
+  else
+    machineid = assert(io_popen("uname -n")):read("*l")
+  end
+  machineid = ngx_md5_bin(machineid):sub(1, 3)
+  return machineid
+end
+
+local pid
+local function _get_os_pid()
+  pid = num_to_le_uint(ngx.var.pid, 2)
+  return pid 
+end
+
+local inc = 0
+local function _generate_id()
+  inc = inc + 1
+  -- "A BSON ObjectID is a 12-byte value consisting of a 4-byte timestamp (seconds since epoch), a 3-byte machine id, a 2-byte process id, and a 3-byte counter. Note that the timestamp and counter fields must be stored big endian unlike the rest of BSON"
+  return num_to_be_uint(os_time(), 4) .. (machineid or _get_os_machineid()) .. (pid or _get_os_pid()) .. num_to_be_uint(inc, 3)
+end
+
+local function _new(cls, id) 
+  if id then
+    if type(id) == 'string' then
+      local len = #id
+      if len == 12 then
+      elseif len == 16 then
+        id = ngx_decode_base64((id:gsub('!', '+'):gsub('_', '/')))
+      else
+        return nil, 'expecting string is 12 or 16 length'
+      end
+    else
+      return nil, 'expecting id is string or nil'
+    end
+  end
+  local o = { id = id or _generate_id() }
+  setmetatable(o, cls)
+  return o
+end
+
+setmetatable(_M, { __call = _new })
+
+__index = _M
+
+__tostring = function(ob)
+  return ngx_encode_base64(ob.id):gsub('%+', '!'):gsub('/', '_')
+end
+
+__tojson = __tostring
+
+__eq = function (a, b)
+  return a.id == b.id
+end
+
+tostring = __tostring
+
+function get_ts(ob)
+  return be_uint_to_num(ob.id, 1, 4)
+end
+
+function get_pid(ob)
+  return be_uint_to_num(ob.id, 8, 9)
+end
+
+function get_hostname(ob)
+  local t = {}
+  for i = 5, 7 do
+    table_insert(t, string_format("%02x", string_byte(ob.id, i, i))) 
+  end
+  return table_concat(t)
+end
+
+function get_inc(ob)
+  return be_uint_to_num(ob.id, 10, 12)
+end