From 47582941f65718149fecbc306e4554f421086a48 Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Fri, 23 Aug 2013 13:14:42 +0800
Subject: [PATCH 01/23] - fixed random crash by ll.lua's assert - fixed cannot
 load by init_by_lua, because used ngx.var.pid in module file scope, so moved
 to function run time scope

---
 lib/resty/mongol/ll.lua        |  2 --
 lib/resty/mongol/object_id.lua | 23 +++++++++++++++--------
 2 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/lib/resty/mongol/ll.lua b/lib/resty/mongol/ll.lua
index ec06645..49312c9 100644
--- a/lib/resty/mongol/ll.lua
+++ b/lib/resty/mongol/ll.lua
@@ -31,7 +31,6 @@ local num_to_le_uint = function ( n , bytes )
 	for i=1 , bytes do
 		b [ i ] , n = n % 2^8 , floor ( n / 2^8 )
 	end
-	assert ( n == 0 )
 	return strchar ( unpack ( b ) )
 end
 local num_to_le_int = function ( n , bytes )
@@ -57,7 +56,6 @@ local num_to_be_uint = function ( n , bytes )
 	for i=bytes , 1 , -1 do
 		b [ i ] , n = n % 2^8 , floor ( n / 2^8 )
 	end
-	assert ( n == 0 )
 	return strchar ( unpack ( b ) )
 end
 
diff --git a/lib/resty/mongol/object_id.lua b/lib/resty/mongol/object_id.lua
index fc3f2bb..88f6b52 100755
--- a/lib/resty/mongol/object_id.lua
+++ b/lib/resty/mongol/object_id.lua
@@ -46,20 +46,27 @@ local object_id_mt = {
 }
 
 local machineid
-if hasposix then
-    machineid = posix.uname("%n")
-else
-    machineid = assert(io.popen("uname -n")):read("*l")
+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
-machineid = ngx.md5_bin(machineid):sub(1, 3)
 
-local pid = num_to_le_uint(ngx.var.pid, 2)
+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 ( )
+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 .. pid .. num_to_be_uint ( inc , 3 )
+    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_object_id(str)

From 9a2724dd5e96c993e850b03f7e76260bbd0d217d Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Sun, 25 Aug 2013 23:23:10 +0800
Subject: [PATCH 02/23] - fixed to_bson not serialize lua table begin from 1

---
 lib/resty/mongol/bson.lua | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/resty/mongol/bson.lua b/lib/resty/mongol/bson.lua
index 8abcf98..e944875 100755
--- a/lib/resty/mongol/bson.lua
+++ b/lib/resty/mongol/bson.lua
@@ -157,13 +157,13 @@ end
 function to_bson(ob)
 	-- Find out if ob if an array; string->value map; or general table
 	local onlyarray = true
-	local seen_n , high_n = { } , 0
+	local seen_n , high_n = { } , 1
 	local onlystring = true
 	for k , v in pairs ( ob ) do
 		local t_k = type ( k )
 		onlystring = onlystring and ( t_k == "string" )
 		if onlyarray then
-			if t_k == "number" and k >= 0 then
+			if t_k == "number" and k >= 1 then
 				if k >= high_n then
 					high_n = k
 					seen_n [ k ] = v
@@ -186,7 +186,7 @@ function to_bson(ob)
 	elseif onlyarray then
 		local r = { }
 
-		local low = 0
+		local low = 1
 		--if seen_n [ 0 ] then low = 0 end
 		for i=low , high_n do
 			r [ i ] = pack ( i , seen_n [ i ] )

From 8317a437d408258a9db8a2e2bbf6fde3f78af99b Mon Sep 17 00:00:00 2001
From: steven123 <steven.kleinert@bluewin.ch>
Date: Thu, 19 Sep 2013 04:34:20 +0800
Subject: [PATCH 03/23] Added 32bit & 64bit int support

---
 lib/resty/mongol/bson.lua | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/resty/mongol/bson.lua b/lib/resty/mongol/bson.lua
index e944875..ffde52a 100755
--- a/lib/resty/mongol/bson.lua
+++ b/lib/resty/mongol/bson.lua
@@ -124,7 +124,13 @@ local function pack ( k , v )
 	local mt = getmetatable ( v )
 
 	if ot == "number" then
-		return "\1" .. k .. "\0" .. to_double ( v )
+		if math.floor(v) ~= v then
+      		return "\1" .. k .. "\0" .. to_double ( v )
+   		elseif v > 2147483647 or v < -2147483648 then -- 64bit
+      		return "\18" .. k .. "\0" .. num_to_le_int ( v , 8 )
+  		 else -- 32bit
+      		return "\16" .. k .. "\0" .. num_to_le_int ( v , 4 )
+   		end
 	elseif ot == "nil" then
 		return "\10" .. k .. "\0"
 	elseif ot == "string" then

From 3d59d5128471e56056e9be2aa796c396653f53e2 Mon Sep 17 00:00:00 2001
From: steven123 <steven.kleinert@bluewin.ch>
Date: Thu, 19 Sep 2013 05:52:16 +0800
Subject: [PATCH 04/23] to_bson userdata = null

---
 lib/resty/mongol/bson.lua | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/resty/mongol/bson.lua b/lib/resty/mongol/bson.lua
index ffde52a..1fa60f8 100755
--- a/lib/resty/mongol/bson.lua
+++ b/lib/resty/mongol/bson.lua
@@ -133,6 +133,8 @@ local function pack ( k , v )
    		end
 	elseif ot == "nil" then
 		return "\10" .. k .. "\0"
+	elseif ot == "userdata" then
+		return "\10" .. k .. "\0"
 	elseif ot == "string" then
 		return "\2" .. k .. "\0" .. num_to_le_uint ( #v + 1 ) .. v .. "\0"
 	elseif ot == "boolean" then

From abeb135e26b6b5e33f1a0b7684079dea70b8add3 Mon Sep 17 00:00:00 2001
From: steven123 <steven.kleinert@bluewin.ch>
Date: Thu, 19 Sep 2013 06:54:23 +0800
Subject: [PATCH 05/23] check for empty array with ascii 5 if so insert an
 empty array not object

---
 lib/resty/mongol/bson.lua | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/resty/mongol/bson.lua b/lib/resty/mongol/bson.lua
index 1fa60f8..bbea483 100755
--- a/lib/resty/mongol/bson.lua
+++ b/lib/resty/mongol/bson.lua
@@ -152,6 +152,9 @@ local function pack ( k , v )
                v.st .. v.v
 	elseif ot == "table" then
 		local doc , array = to_bson(v)
+		if string.byte(doc) == 5 then
+			return "\4" .. k .. "\0" .. doc
+		end
 		if array then
 			return "\4" .. k .. "\0" .. doc
 		else

From 87f214e6f0207cc7669067d368dcf8eeb3ea5bd2 Mon Sep 17 00:00:00 2001
From: steven123 <steven.kleinert@bluewin.ch>
Date: Sat, 21 Sep 2013 01:14:34 +0800
Subject: [PATCH 06/23] Added query example with order and regex

---
 Readme.md                 | 49 +++++++++++++++++++++++++++++++++++++--
 lib/resty/mongol/bson.lua |  2 +-
 2 files changed, 48 insertions(+), 3 deletions(-)

diff --git a/Readme.md b/Readme.md
index 4eb694d..c724fef 100644
--- a/Readme.md
+++ b/Readme.md
@@ -234,8 +234,8 @@ 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
 ---------------------------
@@ -252,6 +252,51 @@ Example
 
             r = col:find_one({name="dog"})
             ngx.say(r["name"])
+			
+Example using query and order
+---------------------------
+            local mongo = require "resty.mongol"
+            conn = mongo:new()
+            conn:set_timeout(1000)
+            ok, err = conn:connect()
+            if not ok then
+                ngx.say("connect failed: "..err)
+            end
+
+            local db = conn:new_db_handle ( "test" )
+            col = db:get_col("test")
+			local sel = {}
+			sel = {name="dog"}
+			local field = {}
+			field['name'] = -1
+            id, results, t = col:query({query=sel,orderby=field},returnfields,0,10);
+            ngx.say(results[1]["name"])
+			
+Example query with regex and order
+---------------------------
+            local mongo = require "resty.mongol"
+            conn = mongo:new()
+            conn:set_timeout(1000)
+            ok, err = conn:connect()
+            if not ok then
+                ngx.say("connect failed: "..err)
+            end
+
+            local db = conn:new_db_handle ( "test" )
+            col = db:get_col("test")
+
+			local field = {}
+			field['name'] = -1
+			
+			local regex = {}
+			regex['$regex'] = 'do.*'
+			regex['$options'] = 'i'
+			
+			local sel = {}
+			sel = {name=regex}
+			
+            id, results, t = col:query({query=sel,orderby=field},returnfields,0,10);
+            ngx.say(results[1]["name"])
 
 For Test Case
 --------------------
diff --git a/lib/resty/mongol/bson.lua b/lib/resty/mongol/bson.lua
index bbea483..6a91175 100755
--- a/lib/resty/mongol/bson.lua
+++ b/lib/resty/mongol/bson.lua
@@ -71,7 +71,7 @@ local function read_document ( get , numerical )
 			v = nil
 		elseif op == "\16" then --int32
 			v = le_int_to_num ( get ( 4 ) , 1 , 8 )
-        elseif op == "\17" then --int64
+        elseif op == "\17" then --int64 // timestamp
             v = le_int_to_num(get(8), 1, 8)
         elseif op == "\18" then --int64
             v = le_int_to_num(get(8), 1, 8)

From 82093f794f4fc00a8248e3c63fd2b372cb0652f5 Mon Sep 17 00:00:00 2001
From: steven123 <steven.kleinert@bluewin.ch>
Date: Sat, 21 Sep 2013 06:26:37 +0800
Subject: [PATCH 07/23] fic bson & add more exaples

---
 Readme.md                 | 38 ++++++++++++++++++++++++++++++++++++++
 lib/resty/mongol/bson.lua |  6 +++---
 2 files changed, 41 insertions(+), 3 deletions(-)

diff --git a/Readme.md b/Readme.md
index c724fef..5943888 100644
--- a/Readme.md
+++ b/Readme.md
@@ -298,6 +298,44 @@ Example query with regex and order
             id, results, t = col:query({query=sel,orderby=field},returnfields,0,10);
             ngx.say(results[1]["name"])
 
+Example query with or modifier and regex
+---------------------------
+			local query_object = {}
+			local or_object = {}
+			local array_of_or_objects = {}
+
+			local title_regex = {}
+			title_regex['$regex'] = '^' .. query_string .. '.*'
+			title_regex['$options'] = 'i'
+
+			local imdb_regex = {}
+			imdb_regex['$regex'] = '^' .. query_string .. '.*'
+			imdb_regex['$options'] = 'i'
+
+			local year_regex = {}
+			year_regex['$regex'] = '^' .. query_string .. '.*'
+			year_regex['$options'] = 'i'
+
+			local title_object = {title=title_regex}
+			local imdb_object = {imdb_id=imdb_regex}
+			local year_object = {year=year_regex}
+
+			array_of_or_objects[1] = title_object
+			array_of_or_objects[2] = imdb_object
+			array_of_or_objects[3] = year_object
+
+			or_object['$or'] = array_of_or_objects
+			query_object['$query'] = query_or
+
+			local returnfields = {id=1,poster_path=1,title=1,popularity=1,vote_average=1,release_date=1}
+			id, results, t = col:query(query_object,returnfields,0,20);
+
+			if not results then
+				ngx.say('No results')
+			end
+			ngx.say(results[1]['title'])
+
+
 For Test Case
 --------------------
 #####mongo config:
diff --git a/lib/resty/mongol/bson.lua b/lib/resty/mongol/bson.lua
index 6a91175..0cf9bcc 100755
--- a/lib/resty/mongol/bson.lua
+++ b/lib/resty/mongol/bson.lua
@@ -168,13 +168,13 @@ end
 function to_bson(ob)
 	-- Find out if ob if an array; string->value map; or general table
 	local onlyarray = true
-	local seen_n , high_n = { } , 1
+	local seen_n , high_n = { } , 0
 	local onlystring = true
 	for k , v in pairs ( ob ) do
 		local t_k = type ( k )
 		onlystring = onlystring and ( t_k == "string" )
 		if onlyarray then
-			if t_k == "number" and k >= 1 then
+			if t_k == "number" and k >= 0 then
 				if k >= high_n then
 					high_n = k
 					seen_n [ k ] = v
@@ -190,7 +190,7 @@ function to_bson(ob)
 	if onlystring then -- Do string first so the case of an empty table is done properly
 		local r = { }
         for k , v in pairs ( ob ) do
---ngx.log(ngx.ERR,"="..k..i)
+
             t_insert ( r , pack ( k , v ) )
         end
 		m = t_concat ( r )

From 4c35e06c8ab5d51f57a5d38b34b7c552e2309a8e Mon Sep 17 00:00:00 2001
From: steven123 <steven.kleinert@bluewin.ch>
Date: Mon, 23 Sep 2013 14:20:34 +0800
Subject: [PATCH 08/23] Update bson.lua

revert back start from 0 for advance queries
---
 lib/resty/mongol/bson.lua | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/resty/mongol/bson.lua b/lib/resty/mongol/bson.lua
index 0cf9bcc..157bba2 100755
--- a/lib/resty/mongol/bson.lua
+++ b/lib/resty/mongol/bson.lua
@@ -197,7 +197,7 @@ function to_bson(ob)
 	elseif onlyarray then
 		local r = { }
 
-		local low = 1
+		local low = 0
 		--if seen_n [ 0 ] then low = 0 end
 		for i=low , high_n do
 			r [ i ] = pack ( i , seen_n [ i ] )

From e053b394eb600b7220b1f1415cf95cb6ff293f12 Mon Sep 17 00:00:00 2001
From: steven123 <steven.kleinert@bluewin.ch>
Date: Mon, 23 Sep 2013 14:39:49 +0800
Subject: [PATCH 09/23] More examples

---
 Readme.md | 85 ++-----------------------------------------------------
 1 file changed, 3 insertions(+), 82 deletions(-)

diff --git a/Readme.md b/Readme.md
index 5943888..44d8825 100644
--- a/Readme.md
+++ b/Readme.md
@@ -237,7 +237,7 @@ Known Issues
 2. Gridfs_new api only create a meta info in file_col.
 
 
-Example
+Basic Usage
 ---------------------------
             local mongo = require "resty.mongol"
             conn = mongo:new()
@@ -253,89 +253,10 @@ Example
             r = col:find_one({name="dog"})
             ngx.say(r["name"])
 			
-Example using query and order
----------------------------
-            local mongo = require "resty.mongol"
-            conn = mongo:new()
-            conn:set_timeout(1000)
-            ok, err = conn:connect()
-            if not ok then
-                ngx.say("connect failed: "..err)
-            end
-
-            local db = conn:new_db_handle ( "test" )
-            col = db:get_col("test")
-			local sel = {}
-			sel = {name="dog"}
-			local field = {}
-			field['name'] = -1
-            id, results, t = col:query({query=sel,orderby=field},returnfields,0,10);
-            ngx.say(results[1]["name"])
-			
-Example query with regex and order
----------------------------
-            local mongo = require "resty.mongol"
-            conn = mongo:new()
-            conn:set_timeout(1000)
-            ok, err = conn:connect()
-            if not ok then
-                ngx.say("connect failed: "..err)
-            end
-
-            local db = conn:new_db_handle ( "test" )
-            col = db:get_col("test")
-
-			local field = {}
-			field['name'] = -1
-			
-			local regex = {}
-			regex['$regex'] = 'do.*'
-			regex['$options'] = 'i'
-			
-			local sel = {}
-			sel = {name=regex}
-			
-            id, results, t = col:query({query=sel,orderby=field},returnfields,0,10);
-            ngx.say(results[1]["name"])
-
-Example query with or modifier and regex
----------------------------
-			local query_object = {}
-			local or_object = {}
-			local array_of_or_objects = {}
-
-			local title_regex = {}
-			title_regex['$regex'] = '^' .. query_string .. '.*'
-			title_regex['$options'] = 'i'
-
-			local imdb_regex = {}
-			imdb_regex['$regex'] = '^' .. query_string .. '.*'
-			imdb_regex['$options'] = 'i'
-
-			local year_regex = {}
-			year_regex['$regex'] = '^' .. query_string .. '.*'
-			year_regex['$options'] = 'i'
-
-			local title_object = {title=title_regex}
-			local imdb_object = {imdb_id=imdb_regex}
-			local year_object = {year=year_regex}
-
-			array_of_or_objects[1] = title_object
-			array_of_or_objects[2] = imdb_object
-			array_of_or_objects[3] = year_object
-
-			or_object['$or'] = array_of_or_objects
-			query_object['$query'] = query_or
-
-			local returnfields = {id=1,poster_path=1,title=1,popularity=1,vote_average=1,release_date=1}
-			id, results, t = col:query(query_object,returnfields,0,20);
-
-			if not results then
-				ngx.say('No results')
-			end
-			ngx.say(results[1]['title'])
 
+See wiki for advanced examples
 
+ 
 For Test Case
 --------------------
 #####mongo config:

From 8121adf6fedbe08cd482c3d1d96c57a6972388e9 Mon Sep 17 00:00:00 2001
From: steven123 <steven.kleinert@bluewin.ch>
Date: Wed, 9 Oct 2013 03:42:55 +0800
Subject: [PATCH 10/23] Start lua index from 1 but bson from 0

	we start the array count from 0 but need to add 1 to mongo array start from 0
lua from 1
start the array building loop from 0
and compensate it by adding 1 to seen_n
and removing 1 from high_n
seems to work??
---
 lib/resty/mongol/bson.lua | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/lib/resty/mongol/bson.lua b/lib/resty/mongol/bson.lua
index 157bba2..95ad097 100755
--- a/lib/resty/mongol/bson.lua
+++ b/lib/resty/mongol/bson.lua
@@ -168,13 +168,13 @@ end
 function to_bson(ob)
 	-- Find out if ob if an array; string->value map; or general table
 	local onlyarray = true
-	local seen_n , high_n = { } , 0
+	local seen_n , high_n = { } , 1
 	local onlystring = true
 	for k , v in pairs ( ob ) do
 		local t_k = type ( k )
 		onlystring = onlystring and ( t_k == "string" )
 		if onlyarray then
-			if t_k == "number" and k >= 0 then
+			if t_k == "number" and k >= 1 then
 				if k >= high_n then
 					high_n = k
 					seen_n [ k ] = v
@@ -198,12 +198,14 @@ function to_bson(ob)
 		local r = { }
 
 		local low = 0
-		--if seen_n [ 0 ] then low = 0 end
+		--[[
+		mongo array start from 0 and lua from 1
+		]]--
 		for i=low , high_n do
-			r [ i ] = pack ( i , seen_n [ i ] )
+			r [ i ] = pack ( i , seen_n [ i + 1 ] )
 		end
-
-		m = t_concat ( r , "" , low , high_n )
+		local h = high_n - 1
+		m = t_concat ( r , "" , low , h )
 		retarray = true
 	else
 		local ni = 1

From 8bb5e7eaba03ea4ff94251fd5b74335cf5d1ab1e Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Fri, 25 Oct 2013 01:23:30 +0800
Subject: [PATCH 11/23] - added Array class support - fixed to_bson incorrectly
 handle array index

---
 lib/resty/mongol/bson.lua | 362 +++++++++++++++++++-------------------
 1 file changed, 182 insertions(+), 180 deletions(-)

diff --git a/lib/resty/mongol/bson.lua b/lib/resty/mongol/bson.lua
index 95ad097..f488bd1 100755
--- a/lib/resty/mongol/bson.lua
+++ b/lib/resty/mongol/bson.lua
@@ -7,10 +7,13 @@ local type = type
 local tonumber , tostring = tonumber , tostring
 local t_insert = table.insert
 local t_concat = table.concat
+local t_maxn = table.maxn
 local strformat = string.format
 local strmatch = string.match
 local strbyte = string.byte
 
+local Array = Array
+
 local ll = require ( mod_name .. ".ll" )
 local le_uint_to_num = ll.le_uint_to_num
 local le_int_to_num = ll.le_int_to_num
@@ -28,202 +31,201 @@ local object_id_mt = obid.metatable
 local binary_mt = {}
 local utc_date = {}
 
-
-local function read_document ( get , numerical )
-	local bytes = le_uint_to_num ( get ( 4 ) )
-
-	local ho , hk , hv = false , false , false
-	local t = { }
-	while true do
-		local op = get ( 1 )
-		if op == "\0" then break end
-
-		local e_name = read_terminated_string ( get )
-		local v
-		if op == "\1" then -- Double
-			v = from_double ( get ( 8 ) )
-		elseif op == "\2" then -- String
-			local len = le_uint_to_num ( get ( 4 ) )
-			v = get ( len - 1 )
-			assert ( get ( 1 ) == "\0" )
-		elseif op == "\3" then -- Embedded document
-			v = read_document ( get , false )
-		elseif op == "\4" then -- Array
-			v = read_document ( get , true )
-		elseif op == "\5" then -- Binary
-			local len = le_uint_to_num ( get ( 4 ) )
-			local subtype = get ( 1 )
-			v = get ( len )
-		elseif op == "\7" then -- ObjectId
-			v = new_object_id ( get ( 12 ) )
-		elseif op == "\8" then -- false
-			local f = get ( 1 )
-			if f == "\0" then
-				v = false
-			elseif f == "\1" then
-				v = true
-			else
-				error ( f:byte ( ) )
-			end
-		elseif op == "\9" then -- UTC datetime milliseconds
-			v = le_uint_to_num ( get ( 8 ) , 1 , 8 )
-		elseif op == "\10" then -- Null
-			v = nil
-		elseif op == "\16" then --int32
-			v = le_int_to_num ( get ( 4 ) , 1 , 8 )
-        elseif op == "\17" then --int64 // timestamp
-            v = le_int_to_num(get(8), 1, 8)
-        elseif op == "\18" then --int64
-            v = le_int_to_num(get(8), 1, 8)
-		else
-			error ( "Unknown BSON type: " .. strbyte ( op ) )
-		end
-
-		if numerical then
-			t [ tonumber ( e_name ) ] = v
-		else
-			t [ e_name ] = v
-		end
-
-		-- Check for special universal map
-		if e_name == "_keys" then
-			hk = v
-		elseif e_name == "_vals" then
-			hv = v
-		else
-			ho = true
-		end
-	end
-
-	if not ho and hk and hv then
-		t = { }
-			for i=1,#hk do
-			t [ hk [ i ] ] = hv [ i ]
-		end
-	end
-
-	return t
+local function read_document(get, numerical)
+  local bytes = le_uint_to_num(get(4))
+
+  local ho, hk, hv = false, false, false
+  local t = {}
+  while true do
+    local op = get(1)
+    if op == "\0" then break end
+
+    local e_name = read_terminated_string(get)
+    local v
+    if op == "\1" then -- Double
+      v = from_double(get(8))
+    elseif op == "\2" then -- String
+      local len = le_uint_to_num(get(4))
+      v = get(len - 1)
+      assert(get(1) == "\0")
+    elseif op == "\3" then -- Embedded document
+      v = read_document(get, false)
+    elseif op == "\4" then -- Array
+      v = read_document(get, true)
+      if Array then
+        v = Array(v)
+      end
+    elseif op == "\5" then -- Binary
+      local len = le_uint_to_num(get(4))
+      local subtype = get(1)
+      v = get(len)
+    elseif op == "\7" then -- ObjectId
+      v = new_object_id(get(12))
+    elseif op == "\8" then -- false
+      local f = get(1)
+      if f == "\0" then
+        v = false
+      elseif f == "\1" then
+        v = true
+      else
+        error(f:byte())
+      end
+    elseif op == "\9" then -- UTC datetime milliseconds
+      v = le_uint_to_num(get(8), 1, 8)
+    elseif op == "\10" then -- Null
+      v = nil
+    elseif op == "\16" then --int32
+      v = le_int_to_num(get(4), 1, 8)
+    elseif op == "\17" then --int64 // timestamp
+      v = le_int_to_num(get(8), 1, 8)
+    elseif op == "\18" then --int64
+      v = le_int_to_num(get(8), 1, 8)
+    else
+      error ( "Unknown BSON type: " .. strbyte(op))
+    end
+
+    if numerical then
+      t[tonumber(e_name)] = v
+    else
+      t[e_name] = v
+    end
+
+    -- Check for special universal map
+    if e_name == "_keys" then
+      hk = v
+    elseif e_name == "_vals" then
+      hv = v
+    else
+      ho = true
+    end
+  end
+
+  if not ho and hk and hv then
+    t = {}
+    for i = 1, #hk do
+      t[hk[i]] = hv[i]
+    end
+  end
+
+  return t
 end
 
 local function get_utc_date(v)
-    return setmetatable({v = v}, utc_date)
+  return setmetatable({v = v}, utc_date)
 end
 
 local function get_bin_data(v)
-    return setmetatable({v = v, st = "\0"}, binary_mt)
+  return setmetatable({v = v, st = "\0"}, binary_mt)
 end
 
-local function from_bson ( get )
-	local t = read_document ( get , false )
-	return t
+local function from_bson(get)
+  return read_document(get, false)
 end
 
 local to_bson
-local function pack ( k , v )
-	local ot = type ( v )
-	local mt = getmetatable ( v )
-
-	if ot == "number" then
-		if math.floor(v) ~= v then
-      		return "\1" .. k .. "\0" .. to_double ( v )
-   		elseif v > 2147483647 or v < -2147483648 then -- 64bit
-      		return "\18" .. k .. "\0" .. num_to_le_int ( v , 8 )
-  		 else -- 32bit
-      		return "\16" .. k .. "\0" .. num_to_le_int ( v , 4 )
-   		end
-	elseif ot == "nil" then
-		return "\10" .. k .. "\0"
-	elseif ot == "userdata" then
-		return "\10" .. k .. "\0"
-	elseif ot == "string" then
-		return "\2" .. k .. "\0" .. num_to_le_uint ( #v + 1 ) .. v .. "\0"
-	elseif ot == "boolean" then
-		if v == false then
-			return "\8" .. k .. "\0\0"
-		else
-			return "\8" .. k .. "\0\1"
-		end
-	elseif mt == object_id_mt then
-		return "\7" .. k .. "\0" .. v.id
-	elseif mt == utc_date then
-		return "\9" .. k .. "\0" .. num_to_le_int(v.v, 8)
-	elseif mt == binary_mt then
-		return "\5" .. k .. "\0" .. num_to_le_uint(string.len(v.v)) .. 
-               v.st .. v.v
-	elseif ot == "table" then
-		local doc , array = to_bson(v)
-		if string.byte(doc) == 5 then
-			return "\4" .. k .. "\0" .. doc
-		end
-		if array then
-			return "\4" .. k .. "\0" .. doc
-		else
-			return "\3" .. k .. "\0" .. doc
-		end
-	else
-		error ( "Failure converting " .. ot ..": " .. tostring ( v ) )
-	end
+local function pack(k, v)
+  local ot = type(v)
+  local mt = getmetatable(v)
+
+  if ot == "number" then
+    if math.floor(v) ~= v then
+      return "\1" .. k .. "\0" .. to_double ( v )
+    elseif v > 2147483647 or v < -2147483648 then -- 64bit
+      return "\18" .. k .. "\0" .. num_to_le_int ( v , 8 )
+    else -- 32bit
+      return "\16" .. k .. "\0" .. num_to_le_int ( v , 4 )
+    end
+  elseif ot == "nil" then
+    return "\10" .. k .. "\0"
+  elseif ot == "userdata" then
+    return "\10" .. k .. "\0"
+  elseif ot == "string" then
+    return "\2" .. k .. "\0" .. num_to_le_uint ( #v + 1 ) .. v .. "\0"
+  elseif ot == "boolean" then
+    if v == false then
+      return "\8" .. k .. "\0\0"
+    else
+      return "\8" .. k .. "\0\1"
+    end
+  elseif mt == object_id_mt then
+    return "\7" .. k .. "\0" .. v.id
+  elseif mt == utc_date then
+    return "\9" .. k .. "\0" .. num_to_le_int(v.v, 8)
+  elseif mt == binary_mt then
+    return "\5" .. k .. "\0" .. num_to_le_uint(string.len(v.v)) .. 
+    v.st .. v.v
+  elseif ot == "table" then
+    local doc , array = to_bson(v)
+    if array then
+      return "\4" .. k .. "\0" .. doc
+    else
+      return "\3" .. k .. "\0" .. doc
+    end
+  else
+    error ( "Failure converting " .. ot ..": " .. tostring ( v ) )
+  end
 end
 
 function to_bson(ob)
-	-- Find out if ob if an array; string->value map; or general table
-	local onlyarray = true
-	local seen_n , high_n = { } , 1
-	local onlystring = true
-	for k , v in pairs ( ob ) do
-		local t_k = type ( k )
-		onlystring = onlystring and ( t_k == "string" )
-		if onlyarray then
-			if t_k == "number" and k >= 1 then
-				if k >= high_n then
-					high_n = k
-					seen_n [ k ] = v
-				end
-			else
-				onlyarray = false
-			end
-		end
-		if not onlyarray and not onlystring then break end
-	end
-
-	local retarray , m = false
-	if onlystring then -- Do string first so the case of an empty table is done properly
-		local r = { }
-        for k , v in pairs ( ob ) do
-
-            t_insert ( r , pack ( k , v ) )
+  -- Find out if ob if an array; string->value map; or general table
+  local onlyarray = true
+  local max = 0
+  local onlystring = true
+  if Array then
+    if getmetatable(ob) == Array then
+      max = t_maxn(ob)
+      onlystring = false
+    else
+      onlyarray = false
+    end
+  end
+  if onlystring then
+    for k, v in pairs(ob) do
+      local t_k = type(k)
+      onlystring = onlystring and (t_k == "string")
+      if onlyarray then
+        if t_k == "number" and k >= 1 then
+          if k >= max then
+            max = k
+          end
+        else
+          onlyarray = false
         end
-		m = t_concat ( r )
-	elseif onlyarray then
-		local r = { }
-
-		local low = 0
-		--[[
-		mongo array start from 0 and lua from 1
-		]]--
-		for i=low , high_n do
-			r [ i ] = pack ( i , seen_n [ i + 1 ] )
-		end
-		local h = high_n - 1
-		m = t_concat ( r , "" , low , h )
-		retarray = true
-	else
-		local ni = 1
-		local keys , vals = { } , { }
-		for k , v in pairs ( ob ) do
-			keys [ ni ] = k
-			vals [ ni ] = v
-			ni = ni + 1
-		end
-		return to_bson ( { _keys = keys , _vals = vals } )
-	end
-
-	return num_to_le_uint ( #m + 4 + 1 ) .. m .. "\0" , retarray
+      end
+      if not onlyarray and not onlystring then break end
+    end
+  end
+
+  local retarray, m = false, nil
+  if onlystring then -- Do string first so the case of an empty table is done properly
+    local r = {}
+    for k, v in pairs(ob) do
+      t_insert(r, pack(k, v))
+    end
+    m = t_concat(r)
+  elseif onlyarray then
+    local r = {}
+    for i = 1, max do
+      r[i] = pack(i - 1, ob[i])
+    end
+    m = t_concat(r, "", 1, max)
+    retarray = true
+  else
+    local ni = 1
+    local keys, vals = {}, {}
+    for k, v in pairs(ob) do
+      keys[ni] = k
+      vals[ni] = v
+      ni = ni + 1
+    end
+    return to_bson({_keys = keys, _vals = vals})
+  end
+  return num_to_le_uint(#m + 4 + 1 )..m.."\0", retarray
 end
 
 return {
-	from_bson = from_bson ;
-	to_bson = to_bson ;
-    get_bin_data = get_bin_data;
-    get_utc_date = get_utc_date;
+  from_bson = from_bson;
+  to_bson = to_bson;
+  get_bin_data = get_bin_data;
+  get_utc_date = get_utc_date;
 }

From 8192d933c3e79f6949727cc499ebaf91598fe209 Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Fri, 25 Oct 2013 01:56:27 +0800
Subject: [PATCH 12/23] - fixed read_document, forgot to convert the array to
 start from 1

---
 lib/resty/mongol/bson.lua | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/resty/mongol/bson.lua b/lib/resty/mongol/bson.lua
index f488bd1..74bf8c6 100755
--- a/lib/resty/mongol/bson.lua
+++ b/lib/resty/mongol/bson.lua
@@ -85,7 +85,7 @@ local function read_document(get, numerical)
     end
 
     if numerical then
-      t[tonumber(e_name)] = v
+      t[tonumber(e_name) + 1] = v
     else
       t[e_name] = v
     end

From 54978956b48403a6bd59359224c892143c023c48 Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Fri, 25 Oct 2013 02:40:51 +0800
Subject: [PATCH 13/23] - fixed to_bson dead loop when handle general table

---
 lib/resty/mongol/bson.lua | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/resty/mongol/bson.lua b/lib/resty/mongol/bson.lua
index 74bf8c6..3ee113d 100755
--- a/lib/resty/mongol/bson.lua
+++ b/lib/resty/mongol/bson.lua
@@ -212,7 +212,12 @@ function to_bson(ob)
     retarray = true
   else
     local ni = 1
-    local keys, vals = {}, {}
+    local keys, vals
+    if Array then
+      keys, vals = Array(), Array()
+    else
+      keys, vals = {}, {}
+    end
     for k, v in pairs(ob) do
       keys[ni] = k
       vals[ni] = v

From 4cb722694d06b022dcbea6f1fa6ea4c6c6eab969 Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Fri, 25 Oct 2013 03:00:15 +0800
Subject: [PATCH 14/23] - removed general table support, because it's difficult
 work with JSON. So, now will convert numerical key to string before store to
 mongodb. And for the best practice, should avoid to use numerical key.
 Because there may have conflit, for example: { 'aaa', ["1"] = 'bbb } is
 unknown behavior

---
 lib/resty/mongol/bson.lua | 63 ++++++++-------------------------------
 1 file changed, 13 insertions(+), 50 deletions(-)

diff --git a/lib/resty/mongol/bson.lua b/lib/resty/mongol/bson.lua
index 3ee113d..7810c13 100755
--- a/lib/resty/mongol/bson.lua
+++ b/lib/resty/mongol/bson.lua
@@ -34,7 +34,6 @@ local utc_date = {}
 local function read_document(get, numerical)
   local bytes = le_uint_to_num(get(4))
 
-  local ho, hk, hv = false, false, false
   local t = {}
   while true do
     local op = get(1)
@@ -89,24 +88,7 @@ local function read_document(get, numerical)
     else
       t[e_name] = v
     end
-
-    -- Check for special universal map
-    if e_name == "_keys" then
-      hk = v
-    elseif e_name == "_vals" then
-      hv = v
-    else
-      ho = true
-    end
   end
-
-  if not ho and hk and hv then
-    t = {}
-    for i = 1, #hk do
-      t[hk[i]] = hv[i]
-    end
-  end
-
   return t
 end
 
@@ -167,65 +149,46 @@ local function pack(k, v)
 end
 
 function to_bson(ob)
-  -- Find out if ob if an array; string->value map; or general table
-  local onlyarray = true
+  -- Find out if ob if an array; or a table
+  local is_array = true
   local max = 0
-  local onlystring = true
   if Array then
     if getmetatable(ob) == Array then
       max = t_maxn(ob)
-      onlystring = false
     else
-      onlyarray = false
+      is_array = false
     end
-  end
-  if onlystring then
+  else
     for k, v in pairs(ob) do
       local t_k = type(k)
-      onlystring = onlystring and (t_k == "string")
-      if onlyarray then
+      if is_array then
         if t_k == "number" and k >= 1 then
           if k >= max then
             max = k
           end
         else
-          onlyarray = false
+          is_array = false
         end
       end
-      if not onlyarray and not onlystring then break end
+      if not is_array then break end
     end
   end
 
-  local retarray, m = false, nil
-  if onlystring then -- Do string first so the case of an empty table is done properly
-    local r = {}
-    for k, v in pairs(ob) do
-      t_insert(r, pack(k, v))
-    end
-    m = t_concat(r)
-  elseif onlyarray then
+  local m
+  if is_array then
     local r = {}
     for i = 1, max do
       r[i] = pack(i - 1, ob[i])
     end
     m = t_concat(r, "", 1, max)
-    retarray = true
   else
-    local ni = 1
-    local keys, vals
-    if Array then
-      keys, vals = Array(), Array()
-    else
-      keys, vals = {}, {}
-    end
+    local r = {}
     for k, v in pairs(ob) do
-      keys[ni] = k
-      vals[ni] = v
-      ni = ni + 1
+      t_insert(r, pack(tostring(k), v))
     end
-    return to_bson({_keys = keys, _vals = vals})
+    m = t_concat(r)
   end
-  return num_to_le_uint(#m + 4 + 1 )..m.."\0", retarray
+  return num_to_le_uint(#m + 4 + 1 )..m.."\0", is_array
 end
 
 return {

From 8332d8f99caa1bb198696e3633ecb5891f3974f1 Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Wed, 30 Oct 2013 20:53:23 +0800
Subject: [PATCH 15/23] - adjusted object_id tostring and new to use base64

---
 lib/resty/mongol/object_id.lua | 87 ++++++++++++++++++----------------
 1 file changed, 45 insertions(+), 42 deletions(-)

diff --git a/lib/resty/mongol/object_id.lua b/lib/resty/mongol/object_id.lua
index 88f6b52..9305f04 100755
--- a/lib/resty/mongol/object_id.lua
+++ b/lib/resty/mongol/object_id.lua
@@ -6,85 +6,88 @@ local strformat = string.format
 local t_insert = table.insert
 local t_concat = table.concat
 
-local hasposix , posix = pcall ( require , "posix" )
+local hasposix, posix = pcall(require , "posix")
 
-local ll = require ( mod_name .. ".ll" )
+local ngx_decode_base64 = ngx.decode_base64
+local ngx_encode_base64 = ngx.encode_base64
+
+local ll = require(mod_name..".ll")
 local num_to_le_uint = ll.num_to_le_uint
 local num_to_be_uint = ll.num_to_be_uint
 
 local function _tostring(ob)
-    local t = {}
-    for i = 1 , 12 do
-        t_insert(t, strformat("%02x", strbyte(ob.id, i, i))) 
-    end
-    return t_concat(t)
+  return ngx_encode_base64(ob.id):gsub('!', '+'):gsub('*', '/')
 end
 
 local function _get_ts(ob)
-    return ll.be_uint_to_num(ob.id, 1, 4)
+  return ll.be_uint_to_num(ob.id, 1, 4)
 end
 
 local function _get_hostname(ob)
-    local t = {}
-    for i = 5, 7 do
-        t_insert(t, strformat("%02x", strbyte(ob.id, i, i))) 
-    end
-    return t_concat(t)
+  local t = {}
+  for i = 5, 7 do
+    t_insert(t, strformat("%02x", strbyte(ob.id, i, i))) 
+  end
+  return t_concat(t)
 end
 
 local function _get_pid(ob)
-    return ll.be_uint_to_num(ob.id, 8, 9)
+  return ll.be_uint_to_num(ob.id, 8, 9)
 end
 
 local function _get_inc(ob)
-    return ll.be_uint_to_num(ob.id, 10, 12)
+  return ll.be_uint_to_num(ob.id, 10, 12)
 end
 
 local object_id_mt = {
-    __tostring = _tostring;
-    __eq = function ( a , b ) return a.id == b.id end ;
+  __tostring = _tostring;
+  __eq = function ( a , b ) return a.id == b.id end ;
 }
 
 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
+  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 
+  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)
+  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_object_id(str)
-    if str then
-        assert(#str == 12)
-    else
-        str = generate_id()
+  local id
+  if type(str) == 'string' then
+    if #str == 12 then
+      id = str
+    elseif #str == 16 then
+      id = ngx_decode_base64(sid:gsub('+', '!'):gsub('/', '*'))
     end
-    return setmetatable({id = str,
-                        tostring = _tostring,
-                        get_ts = _get_ts,
-                        get_pid = _get_pid,
-                        get_hostname = _get_hostname,
-                        get_inc = _get_inc,
-                        } , object_id_mt)
+  end
+  return setmetatable({
+    id = id or generate_id(),
+    tostring = _tostring,
+    get_ts = _get_ts,
+    get_pid = _get_pid,
+    get_hostname = _get_hostname,
+    get_inc = _get_inc,
+  }, object_id_mt)
 end
 
 return {
-    new = new_object_id ;
-    metatable = object_id_mt ;
+  new = new_object_id;
+  metatable = object_id_mt;
 }

From c267f93bf902279ffcceea37ea56f2a58b4e7d08 Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Wed, 30 Oct 2013 23:25:51 +0800
Subject: [PATCH 16/23] - changed * to .

---
 lib/resty/mongol/object_id.lua | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/lib/resty/mongol/object_id.lua b/lib/resty/mongol/object_id.lua
index 9305f04..152067d 100755
--- a/lib/resty/mongol/object_id.lua
+++ b/lib/resty/mongol/object_id.lua
@@ -16,7 +16,7 @@ local num_to_le_uint = ll.num_to_le_uint
 local num_to_be_uint = ll.num_to_be_uint
 
 local function _tostring(ob)
-  return ngx_encode_base64(ob.id):gsub('!', '+'):gsub('*', '/')
+  return ngx_encode_base64(ob.id):gsub('!', '+'):gsub('.', '/')
 end
 
 local function _get_ts(ob)
@@ -71,10 +71,11 @@ end
 local function new_object_id(str)
   local id
   if type(str) == 'string' then
-    if #str == 12 then
+    local len = #str
+    if len == 12 then
       id = str
-    elseif #str == 16 then
-      id = ngx_decode_base64(sid:gsub('+', '!'):gsub('/', '*'))
+    elseif len == 16 then
+      id = ngx_decode_base64(sid:gsub('+', '!'):gsub('/', '.'))
     end
   end
   return setmetatable({

From f813d4dc3be5563ec9572ae228bc43daf5788efc Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Fri, 1 Nov 2013 01:10:51 +0800
Subject: [PATCH 17/23] - refactored object_id to ObjectId

---
 lib/resty/mongol/ObjectId.lua    | 97 ++++++++++++++++++++++++++++++++
 lib/resty/mongol/bson.lua        | 10 ++--
 lib/resty/mongol/gridfs.lua      | 12 ++--
 lib/resty/mongol/gridfs_file.lua |  4 +-
 lib/resty/mongol/misc.lua        |  5 +-
 lib/resty/mongol/object_id.lua   | 94 -------------------------------
 6 files changed, 111 insertions(+), 111 deletions(-)
 create mode 100755 lib/resty/mongol/ObjectId.lua
 delete mode 100755 lib/resty/mongol/object_id.lua

diff --git a/lib/resty/mongol/ObjectId.lua b/lib/resty/mongol/ObjectId.lua
new file mode 100755
index 0000000..f24537d
--- /dev/null
+++ b/lib/resty/mongol/ObjectId.lua
@@ -0,0 +1,97 @@
+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 function _tostring(ob)
+  return ngx_encode_base64(ob.id):gsub('!', '+'):gsub('%.', '/')
+end
+
+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 _new = function(cls, id) 
+  assert(id == nil or type(id) == 'string')
+  if id then
+    local len = #id
+    assert(len == 12 or len == 16)
+    if len == 16 then
+      id = ngx_decode_base64((id:gsub('%+', '!'):gsub('/', '.')))
+    end
+  end
+  local o = { id = id or _generate_id() }
+  setmetatable(o, cls)
+  return o
+end
+
+__index = _M
+__tostring = _tostring
+__eq = function (a, b)
+  return a.id == b.id
+end
+
+setmetatable(_M, { __call = _new })
+
+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
diff --git a/lib/resty/mongol/bson.lua b/lib/resty/mongol/bson.lua
index 7810c13..6e590a0 100755
--- a/lib/resty/mongol/bson.lua
+++ b/lib/resty/mongol/bson.lua
@@ -22,12 +22,10 @@ local num_to_le_int = ll.num_to_le_int
 local from_double = ll.from_double
 local to_double = ll.to_double
 
-local getlib = require ( mod_name .. ".get" )
+local getlib = require(mod_name..".get")
 local read_terminated_string = getlib.read_terminated_string
 
-local obid = require ( mod_name .. ".object_id" )
-local new_object_id = obid.new
-local object_id_mt = obid.metatable
+local ObjectId = require(mod_name..".ObjectId")
 local binary_mt = {}
 local utc_date = {}
 
@@ -59,7 +57,7 @@ local function read_document(get, numerical)
       local subtype = get(1)
       v = get(len)
     elseif op == "\7" then -- ObjectId
-      v = new_object_id(get(12))
+      v = ObjectId(get(12))
     elseif op == "\8" then -- false
       local f = get(1)
       if f == "\0" then
@@ -129,7 +127,7 @@ local function pack(k, v)
     else
       return "\8" .. k .. "\0\1"
     end
-  elseif mt == object_id_mt then
+  elseif mt == ObjectId then
     return "\7" .. k .. "\0" .. v.id
   elseif mt == utc_date then
     return "\9" .. k .. "\0" .. num_to_le_int(v.v, 8)
diff --git a/lib/resty/mongol/gridfs.lua b/lib/resty/mongol/gridfs.lua
index ff8eb07..2725134 100644
--- a/lib/resty/mongol/gridfs.lua
+++ b/lib/resty/mongol/gridfs.lua
@@ -1,10 +1,10 @@
-local mod_name = (...):match ( "^(.*)%..-$" )
+local mod_name = (...):match( "^(.*)%..-$" )
 
 local md5 = require "resty.md5"
 local str = require "resty.string"
-local bson = require ( mod_name .. ".bson" )
-local object_id = require ( mod_name .. ".object_id" )
-local gridfs_file= require ( mod_name .. ".gridfs_file" )
+local bson = require(mod_name..".bson")
+local ObjectId = require(mod_name..".ObjectId")
+local gridfs_file= require(mod_name..".gridfs_file")
 
 local gridfs_mt = { }
 local gridfs = { __index = gridfs_mt }
@@ -57,7 +57,7 @@ end
 
 function gridfs_mt:new(meta)
     meta = meta or {}
-    meta._id = meta._id or object_id.new()
+    meta._id = meta._id or ObjectId()
     meta.chunkSize = meta.chunkSize or 256*1024
     meta.filename = meta.filename or meta._id:tostring()
 
@@ -81,7 +81,7 @@ end
 function gridfs_mt:insert(fh, meta, safe)
     meta = meta or {}
     meta.chunkSize = meta.chunkSize or 256*1024
-    meta._id = meta._id or object_id.new()
+    meta._id = meta._id or ObjectId()
     meta.filename = meta.filename or meta._id:tostring()
 
     local n = 0
diff --git a/lib/resty/mongol/gridfs_file.lua b/lib/resty/mongol/gridfs_file.lua
index 4a99e16..a9497d7 100644
--- a/lib/resty/mongol/gridfs_file.lua
+++ b/lib/resty/mongol/gridfs_file.lua
@@ -1,8 +1,8 @@
-local mod_name = (...):match ( "^(.*)%..-$" )
+local mod_name = (...):match( "^(.*)%..-$" )
 
 local md5 = require "resty.md5"
 local str = require "resty.string"
-local bson = require ( mod_name .. ".bson" )
+local bson = require(mod_name..".bson")
 
 local gridfs_file_mt = { }
 local gridfs_file = { __index = gridfs_file_mt }
diff --git a/lib/resty/mongol/misc.lua b/lib/resty/mongol/misc.lua
index e676843..812e9d5 100755
--- a/lib/resty/mongol/misc.lua
+++ b/lib/resty/mongol/misc.lua
@@ -1,12 +1,11 @@
-local mod_name = (...):match ( "^(.*)%..-$" )
+local mod_name = (...):match("^(.*)%..-$")
 
-local ll = require ( mod_name .. ".ll" )
+local ll = require(mod_name..".ll")
 local num_to_le_uint = ll.num_to_le_uint
 local num_to_le_int = ll.num_to_le_int
 local le_uint_to_num = ll.le_uint_to_num
 local le_bpeek = ll.le_bpeek
 
-
 local getmetatable , setmetatable = getmetatable , setmetatable
 local pairs = pairs
 local next = next
diff --git a/lib/resty/mongol/object_id.lua b/lib/resty/mongol/object_id.lua
deleted file mode 100755
index 152067d..0000000
--- a/lib/resty/mongol/object_id.lua
+++ /dev/null
@@ -1,94 +0,0 @@
-local mod_name = (...):match ( "^(.*)%..-$" )
-
-local setmetatable = setmetatable
-local strbyte = string.byte
-local strformat = string.format
-local t_insert = table.insert
-local t_concat = table.concat
-
-local hasposix, posix = pcall(require , "posix")
-
-local ngx_decode_base64 = ngx.decode_base64
-local ngx_encode_base64 = ngx.encode_base64
-
-local ll = require(mod_name..".ll")
-local num_to_le_uint = ll.num_to_le_uint
-local num_to_be_uint = ll.num_to_be_uint
-
-local function _tostring(ob)
-  return ngx_encode_base64(ob.id):gsub('!', '+'):gsub('.', '/')
-end
-
-local function _get_ts(ob)
-  return ll.be_uint_to_num(ob.id, 1, 4)
-end
-
-local function _get_hostname(ob)
-  local t = {}
-  for i = 5, 7 do
-    t_insert(t, strformat("%02x", strbyte(ob.id, i, i))) 
-  end
-  return t_concat(t)
-end
-
-local function _get_pid(ob)
-  return ll.be_uint_to_num(ob.id, 8, 9)
-end
-
-local function _get_inc(ob)
-  return ll.be_uint_to_num(ob.id, 10, 12)
-end
-
-local object_id_mt = {
-  __tostring = _tostring;
-  __eq = function ( a , b ) return a.id == b.id end ;
-}
-
-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_object_id(str)
-  local id
-  if type(str) == 'string' then
-    local len = #str
-    if len == 12 then
-      id = str
-    elseif len == 16 then
-      id = ngx_decode_base64(sid:gsub('+', '!'):gsub('/', '.'))
-    end
-  end
-  return setmetatable({
-    id = id or generate_id(),
-    tostring = _tostring,
-    get_ts = _get_ts,
-    get_pid = _get_pid,
-    get_hostname = _get_hostname,
-    get_inc = _get_inc,
-  }, object_id_mt)
-end
-
-return {
-  new = new_object_id;
-  metatable = object_id_mt;
-}

From c803a3298f664595a38594dd672451be46404d04 Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Fri, 1 Nov 2013 01:20:43 +0800
Subject: [PATCH 18/23] - changed . to _

---
 lib/resty/mongol/ObjectId.lua | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/resty/mongol/ObjectId.lua b/lib/resty/mongol/ObjectId.lua
index f24537d..a8766e2 100755
--- a/lib/resty/mongol/ObjectId.lua
+++ b/lib/resty/mongol/ObjectId.lua
@@ -25,7 +25,7 @@ local num_to_be_uint = ll.num_to_be_uint
 local be_uint_tonum = ll.be_uint_to_num
 
 local function _tostring(ob)
-  return ngx_encode_base64(ob.id):gsub('!', '+'):gsub('%.', '/')
+  return ngx_encode_base64(ob.id):gsub('!', '+'):gsub('_', '/')
 end
 
 local machineid
@@ -58,7 +58,7 @@ local _new = function(cls, id)
     local len = #id
     assert(len == 12 or len == 16)
     if len == 16 then
-      id = ngx_decode_base64((id:gsub('%+', '!'):gsub('/', '.')))
+      id = ngx_decode_base64((id:gsub('%+', '!'):gsub('/', '_')))
     end
   end
   local o = { id = id or _generate_id() }

From 874e82eade8afa0c0058163b2eeb53f0174726ca Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Fri, 1 Nov 2013 01:47:25 +0800
Subject: [PATCH 19/23] - revised to return nil with error string instead of
 assert

---
 lib/resty/mongol/ObjectId.lua | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/lib/resty/mongol/ObjectId.lua b/lib/resty/mongol/ObjectId.lua
index a8766e2..1256dd9 100755
--- a/lib/resty/mongol/ObjectId.lua
+++ b/lib/resty/mongol/ObjectId.lua
@@ -53,12 +53,17 @@ local function _generate_id()
 end
 
 local _new = function(cls, id) 
-  assert(id == nil or type(id) == 'string')
   if id then
-    local len = #id
-    assert(len == 12 or len == 16)
-    if len == 16 then
-      id = ngx_decode_base64((id:gsub('%+', '!'):gsub('/', '_')))
+    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() }

From adead559b6a2d2c2579e6d176bfc633697283a86 Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Fri, 1 Nov 2013 03:05:00 +0800
Subject: [PATCH 20/23] - minor change for better coding

---
 lib/resty/mongol/ObjectId.lua | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/lib/resty/mongol/ObjectId.lua b/lib/resty/mongol/ObjectId.lua
index 1256dd9..83379d4 100755
--- a/lib/resty/mongol/ObjectId.lua
+++ b/lib/resty/mongol/ObjectId.lua
@@ -24,10 +24,6 @@ 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 function _tostring(ob)
-  return ngx_encode_base64(ob.id):gsub('!', '+'):gsub('_', '/')
-end
-
 local machineid
 local function _get_os_machineid()
   if hasposix then
@@ -52,7 +48,7 @@ local function _generate_id()
   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 _new = function(cls, id) 
+local function _new(cls, id) 
   if id then
     if type(id) == 'string' then
       local len = #id
@@ -71,15 +67,19 @@ local _new = function(cls, id)
   return o
 end
 
+setmetatable(_M, { __call = _new })
+
 __index = _M
-__tostring = _tostring
+
+__tostring = function(ob)
+  return ngx_encode_base64(ob.id):gsub('!', '+'):gsub('_', '/')
+end
+
 __eq = function (a, b)
   return a.id == b.id
 end
 
-setmetatable(_M, { __call = _new })
-
-tostring = _tostring
+tostring = __tostring
 
 function get_ts(ob)
   return be_uint_to_num(ob.id, 1, 4)

From d440a49dac893cda82cbadf713ecebf869c22dc4 Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Mon, 4 Nov 2013 18:24:21 +0800
Subject: [PATCH 21/23] - fixed incorrectly reversed + / and ! _

---
 lib/resty/mongol/ObjectId.lua | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/resty/mongol/ObjectId.lua b/lib/resty/mongol/ObjectId.lua
index 83379d4..904c49f 100755
--- a/lib/resty/mongol/ObjectId.lua
+++ b/lib/resty/mongol/ObjectId.lua
@@ -54,7 +54,7 @@ local function _new(cls, id)
       local len = #id
       if len == 12 then
       elseif len == 16 then
-        id = ngx_decode_base64((id:gsub('%+', '!'):gsub('/', '_')))
+        id = ngx_decode_base64((id:gsub('!', '+'):gsub('_', '/')))
       else
         return nil, 'expecting string is 12 or 16 length'
       end
@@ -72,7 +72,7 @@ setmetatable(_M, { __call = _new })
 __index = _M
 
 __tostring = function(ob)
-  return ngx_encode_base64(ob.id):gsub('!', '+'):gsub('_', '/')
+  return ngx_encode_base64(ob.id):gsub('%+', '!'):gsub('/', '_')
 end
 
 __eq = function (a, b)

From 4b0dcfb72661a454f0fab7b6381a72a3575b2298 Mon Sep 17 00:00:00 2001
From: Payne Chu <payne@piplay.com>
Date: Thu, 19 Dec 2013 14:40:40 +0800
Subject: [PATCH 22/23] - FIX: cjson already referenced to __tojson for
 serialization instead of __tostring

---
 lib/resty/mongol/ObjectId.lua | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/resty/mongol/ObjectId.lua b/lib/resty/mongol/ObjectId.lua
index 904c49f..5ee744d 100755
--- a/lib/resty/mongol/ObjectId.lua
+++ b/lib/resty/mongol/ObjectId.lua
@@ -75,6 +75,8 @@ __tostring = function(ob)
   return ngx_encode_base64(ob.id):gsub('%+', '!'):gsub('/', '_')
 end
 
+__tojson = __tostring
+
 __eq = function (a, b)
   return a.id == b.id
 end

From 07b00b8a958a2ea8ebdbd6684805ab7b7e40091b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Adrian=20=C5=BBurek?= <a.zurek@imerge.pl>
Date: Fri, 10 Jan 2014 12:01:39 +0100
Subject: [PATCH 23/23] update file_size after write

---
 lib/resty/mongol/gridfs_file.lua | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/resty/mongol/gridfs_file.lua b/lib/resty/mongol/gridfs_file.lua
index a9497d7..4e09ecd 100644
--- a/lib/resty/mongol/gridfs_file.lua
+++ b/lib/resty/mongol/gridfs_file.lua
@@ -129,6 +129,8 @@ function gridfs_file_mt:write(buf, offset, size)
         r,err = self.file_col:update({_id = self.files_id},nv, 
                         0, 0, true)
         if not r then return nil,"write failed: "..err end
+
+        self.file_size = nf
     end
 
     nv["$set"] = {md5 = 0}