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The MIT License (MIT)
Based on FlatDB(MIT)
---------------------------
Copyright (C) 2018 Coder12a
Copyright (c) 2015 Peer Zeng
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That's all there is to it!

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FlatDB
===========
FlatDB是一个Lua扩展库，实现一个无服务器的零配置的NoSQL数据引擎。<br>
它提供一个由Lua表构成的键值对存储系统。
FlatDB的使用情境
===========
当您想使用SQLite存储一些数据，而不必用到SQL查询的时候，可以考虑使用FlatDB代替之。<br>
如果您的程序使用的语言恰好是Lua，或者嵌入了Lua作为扩展脚本的话，那么就尝试使用FlatDB来存储数据吧。
概念
==========
| FlatDB | 磁盘 | Lua |
|:--------------:|:------------:|:----------:|
| 数据库 | 目录 | 表 |
| 页（Page） | 文件 | 表 |
| 键值对 | 文件内容 | 键值对 |
该表反映的是FlatDB、磁盘和Lua三个层面的对应关系。<br>
FlatDB将一个目录看作数据库，映射到一个Lua表上。
该Lua表的下级也是一些Lua表，对应FlatDB的页（Page），它将被存储到数据库目录下同名的文件中。
这些文件的内容正是页（Page）中的键值对，即Lua表序列化后的字符串。
键值对中的键和值可以是Lua中所有能够被序列化的类型，即除了协程、用户数据、C数据和C函数外的类型。
用法
==========
将*flatdb.lua*文件复制到你的项目所在或存储Lua扩展库的目录中。<br>
然后在用到它的Lua文件中写上这句话：
```lua
local flatdb = require 'flatdb'
```
1. 将目录作为数据库映射到Lua表中
```lua
local db = flatdb('./db')
```
2. 打开或创建一个页（Page）
```lua
if not db.page then
db.page = {}
end
```
3. 往页（Page）中写入键值对数据
```lua
db.page.key = 'value'
-- equivalent to db.page['key'] = 'value'
```
4. 读取页（Page）中的数据
```lua
print(db.page.key) -- prints 'value'
```
5. 将所有页（Page）数据保存在同名的文件中
```lua
db:save()
-- 'page' will be saved to './db/page'
```
更多用法可参考另一个项目[Ledis](https://github.com/uleelx/ledis)（一个使用FlatDB作为存储后端的Redis实现）。
范例概览
==========
```lua
-- 这是一个以FlatDB作为存储引擎的日志系统例子
local flatdb = require("flatdb")
local logger = flatdb("./log")
local count = 0
local function common_log(logger, level, message)
local today = os.date("%Y-%m-%d")
if logger[today] == nil then logger[today] = {} end
if logger[today][level] == nil then logger[today][level] = {} end
table.insert(logger[today][level], {
timestamp = os.time(),
level = level,
message = message
})
count = (count+1)%10
if count == 0 then
logger:save()
end
end
local levels = {"debug", "info", "warn", "error", "fatal"}
for _, level in ipairs(levels) do
flatdb.hack[level] = function(logger, msg)
common_log(logger, level, msg)
end
end
flatdb.hack.find = function(logger, level, date)
if logger[date or os.date("%Y-%m-%d")] then
return logger[date or os.date("%Y-%m-%d")][level]
end
end
for i = 1, 10 do
logger:debug("This is a debug message.")
logger:info("This is an info message.")
logger:warn("This is a warn message.")
logger:error("This is an error message.")
logger:fatal("This is a fatal message.")
end
local pp = require("pp") -- https://github.com/luapower/pp
pp(logger:find("error"))
```
API
==========
- **函数**
- **flatdb(dir) --> db**
将一个目录dir映射成数据库对象。若目录不存在，返回nil。否则，返回一个数据库对象db（Lua表）。
- **db:save([page])**
将指定的页（Page）保存在文件中，若不指定则保存数据库对象中所有的页。参数*page*是指页的名称。
- **表**
- **flatdb**
当数据库载入后，flatdb表的键值对有以下关系：
*flatdb[dir] --> db*
*flatdb[db] --> dir*
- **flatdb.hack**
hack表包含了数据库对象的所有方法。默认情况下，目前数据库对象只有一个db:save([page])方法。
该表一般用于扩展数据库对象方法。
依赖项
=======
- [lua-MessagePack](https://github.com/fperrad/lua-MessagePack)
许可证
=======
FlatDB是在MIT许可证下发布的。

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FlatDB
===========
FlatDB is a lua library that implements a serverless, zero-configuration, NoSQL database engine.<br>
It provides a key-value storage system using plain Lua tables.
When To Use FlatDB
===========
When you want to use SQLite to store data, just take a glance at FlatDB.<br>
When Lua acts in your program as the major language or the embedded scripting language, just try using FlatDB.
Concept
==========
| FlatDB | Disk | Lua |
|:--------------:|:-------------:|:--------------:|
| Database | Directory | Table |
| Page | File | Table |
| Key-value pair | File content | Key-value pair |
Keys and values can be all Lua types except coroutines, userdata, cdata and C functions.
Usage
==========
Copy *flatdb.lua* file to your project or where your lua libraries stored.<br>
Then write this in any Lua file where you want to use it:
```lua
local flatdb = require 'flatdb'
```
1. Bind a directory as a database
```lua
local db = flatdb('./db')
```
2. Open or create a page
```lua
if not db.page then
db.page = {}
end
```
3. Store key-value items
```lua
db.page.key = 'value'
-- equivalent to db.page['key'] = 'value'
```
4. Retrieve items
```lua
print(db.page.key) -- prints 'value'
```
5. Save to file
```lua
db:save()
-- 'page' will be saved to './db/page'
```
More usage can be found in the [Ledis](https://github.com/uleelx/ledis)(an alternative of Redis server using FlatDB).
Quick Look
==========
```lua
-- This is an logging system example using FlatDB
local flatdb = require("flatdb")
local logger = flatdb("./log")
local count = 0
local function common_log(logger, level, message)
local today = os.date("%Y-%m-%d")
if logger[today] == nil then logger[today] = {} end
if logger[today][level] == nil then logger[today][level] = {} end
table.insert(logger[today][level], {
timestamp = os.time(),
level = level,
message = message
})
count = (count+1)%10
if count == 0 then
logger:save()
end
end
local levels = {"debug", "info", "warn", "error", "fatal"}
for _, level in ipairs(levels) do
flatdb.hack[level] = function(logger, msg)
common_log(logger, level, msg)
end
end
flatdb.hack.find = function(logger, level, date)
if logger[date or os.date("%Y-%m-%d")] then
return logger[date or os.date("%Y-%m-%d")][level]
end
end
for i = 1, 10 do
logger:debug("This is a debug message.")
logger:info("This is an info message.")
logger:warn("This is a warn message.")
logger:error("This is an error message.")
logger:fatal("This is a fatal message.")
end
local pp = require("pp") -- https://github.com/luapower/pp
pp(logger:find("error"))
```
API
==========
- **Functions**
- **flatdb(dir) --> db**
Bind a directory as a database, returns nil if 'dir' doesn't exists. Otherwise, it returns a 'db' obeject.
- **db:save([page])**
Save all pages or the given page(if specified) contained in db to file. The 'page' argument is a string, the page's name.
- **Tables**
- **flatdb**
When a db is loaded, there is two relations below:
*flatdb[dir] --> db*
*flatdb[db] --> dir*
- **flatdb.hack**
The 'hack' table contains db's methods. There is only one method 'save(db, page)' in it by default.
It is usually used to extend db methods.
Dependencies
=======
- [lua-MessagePack](https://github.com/fperrad/lua-MessagePack)
License
=======
FlatDB is distributed under the MIT license.
ColdDB
===========
ColdDB is a lua library that implements a serverless, zero-configuration, NoSQL database engine.

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colddb.lua Normal file
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colddb = {}
local ie = ...
local function createDir(directory)
return minetest.mkdir(directory)
end
function colddb.file_Exists(db,name,tag_name)
local t = ""
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local f = io.open(string.format("%s%s%s.cold",db.directory,t,name),"r")
if f ~= nil then
io.close(f)
return true
else
return false
end
return false
end
function colddb.get_db(directory)
local directory = string.format("%s/%s",minetest.get_worldpath(),directory)
if not createDir(directory) then
error(string.format("%s is not a directory.",directory))
end
db = {
global_tag = "",
directory = directory,
tags = {},
mem_pool = {},
indexes_pool = {},
iterate_queue = {},
indexes = false,
add_to_mem_pool = true,
}
return db
end
function colddb.add_global_tag(db,tag)
local t = ""
if type(tag) == "table" then
for index in pairs(tag) do
t = string.format("%s%s/",t,index)
end
else
t = string.format("%s/",tag)
end
db.global_tag = string.format("%s%s",db.global_tag,t)
db.directory = string.format("%s/%s",db.directory,t)
if not createDir(db.directory) then
error(string.format("%s is not a directory.",db.directory))
end
end
function colddb.add_tag(db,name,tag)
local t = ""
if not db.tags[name] then
db.tags[name] = ""
end
if type(tag) == "table" then
for _index in pairs(tag) do
t = string.format("%s%s/",t,_index)
end
else
t = string.format("%s/",tag)
end
local test_path = string.format("%s%s%s",db.directory,db.tags[name],t)
if not createDir(test_path) then
error(string.format("%s is not a directory.",test_path))
end
db.tags[name] = string.format("%s%s",db.tags[name],t)
end
function colddb.get_tag(db,name)
if not name then
return ""
end
local tag = db.tags[name]
if tag then
return tag
end
return ""
end
function colddb.remove_tag(db,name)
if db.tags[name] then
local delete_path = string.format("%s%s",db.directory,db.tags[name])
local wc = delete_path:len()
delete_path = delete_path:sub(0,wc-1)
db.tags[name] = nil
local err,msg = os.remove(delete_path)
if err == nil and ie then
assert(ie, "Please add colddb to secure.trusted_mods in the settings")
local cmd = string.format("rmdir %s",delete_path)
ie.os.execute(cmd)
cmd = nil
end
end
end
function colddb.delete_file(db,name,tag_name)
local t = ""
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local text = string.format("%s%s%s.cold",db.directory,t,name)
local err,msg = os.remove(text)
if err == nil then
print(string.format("error removing db data %s error message: %s",text,msg))
end
end
function colddb.load_table(db,name,tag_name)
local t = ""
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local f = io.open(string.format("%s%s%s.cold",db.directory,t,name), "r")
if f then
local data = minetest.deserialize(f:read("*a"))
f:close()
return data
end
return nil
end
function colddb.save_table(db,name, _table,tag_name)
local t = ""
if tag_name then
t = colddb.get_tag(db,tag_name)
end
return minetest.safe_file_write(string.format("%s%s%s.cold",db.directory,t,name), minetest.serialize(_table))
end
function colddb.save_key(db,name,tag_name)
local t = ""
if tag_name then
t = colddb.get_tag(db,tag_name)
end
return minetest.safe_file_write(string.format("%s%s%s.cold",db.directory,t,name), "")
end
function colddb.load_key(db,name,tag_name)
local t = ""
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local f = io.open(string.format("%s%s%s.cold",db.directory,t,name), "r")
if f then
f:close()
return true
end
return false
end
function colddb.delete_index_table(db,tag_name)
local t = ""
local name = "æIndex_table"
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local p = string.format("%s%sæIndex_table.cold",db.directory,t)
if colddb.file_Exists(db,name,tag_name) then
local err,msg = os.remove(p)
if err == nil then
print(string.format("error removing db data %s error message: %s",p,msg))
end
return true
end
return false
end
local function delete_lines_func_begin(args)
local f = io.open(args.copyfile, "w")
local db = args.db
local cs = args.cs
if f then
args.file = f
args.removedlist = {}
return args
end
return false
end
local function delete_lines_func_i(line,i,args)
local f = args.file
local db = args.db
local cs = args.cs
local om = db.indexes_pool[args.cs]
if om and not om.deleted_items[line] then
f:write(string.format("\n%s",line))
else
args.count = args.count - 1
args.removedlist[line] = true
end
end
local function delete_lines_func_end(args)
local db = args.db
local cs = args.cs
if db.indexes_pool[cs] or db.indexes_pool[cs].file then
db.indexes_pool[cs].file:close()
db.indexes_pool[cs].file = nil
args.file:seek("set")
args.file:write(string.format("%i",args.count))
args.file:close()
os.remove(args.oldfile)
os.rename(args.copyfile, args.oldfile)
for i,l in pairs(args.removedlist) do
db.indexes_pool[cs].deleted_items[i] = nil
end
db.indexes_pool[cs].deleting = false
end
args = nil
end
function colddb.delete_lines(db,_lines,tag_name)
local t = ""
local name = "æIndex_table"
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local cs = string.format("%s%s",t,name)
local f = db.indexes_pool[cs]
local k = type(_lines)
if k == "string" then
f.deleted_items[_lines] = true
else
for i,l in pairs(_lines) do
f.deleted_items[i] = true
end
end
if not db.indexes_pool[cs].deleting then
db.indexes_pool[cs].deleting = false
end
if f and f.file and not db.indexes_pool[cs].deleting then
db.indexes_pool[cs].deleting = true
if db.indexes_pool[cs].needs_flushing == true then
f.file:flush()
db.indexes_pool[cs].needs_flushing = false
end
local oldfile = string.format("%s%sæIndex_table.cold",db.directory,t)
local copyfile = string.format("%s%sæIndex_table.cold.replacer",db.directory,t)
local args = {db=db,cs=cs,oldfile=oldfile,copyfile=copyfile,do_not_skip_removed_items=true}
db.indexes_pool[cs] = f
colddb.iterate_index_table(db,delete_lines_func_begin,delete_lines_func_i,delete_lines_func_end,150,args,tag_name)
end
end
function colddb.create_index_table(db,tag_name)
local t = ""
local name = "æIndex_table"
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local p = string.format("%s%sæIndex_table.cold",db.directory,t)
if not colddb.file_Exists(db,name,tag_name) then
local f = io.open(p, "w")
if f then
f:seek("set")
f:write("0")
f:close()
end
end
local f = io.open(p, "r+")
if f then
f:seek("set")
f:write("0")
db.indexes_pool[string.format("%s%s",t,name)] = {file = f,needs_flushing = false,deleted_items = {},iterating = false,inuse = false}
return true
end
return false
end
function colddb.open_index_table(db,tag_name)
local t = ""
local name = "æIndex_table"
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local cs = string.format("%s%s",t,name)
local fs = db.indexes_pool[cs]
if not fs then
local p = string.format("%s%sæIndex_table.cold",db.directory,t)
if not colddb.file_Exists(db,name,tag_name) then
local f = io.open(p, "w")
if f then
f:seek("set")
f:write("0")
f:close()
end
end
local f = io.open(p, "r+")
if f then
db.indexes_pool[cs] = {file = f,needs_flushing = false,deleted_items = {},iterating = false,inuse = true}
return f
end
return nil
else
return fs.file
end
return nil
end
function colddb.append_index_table(db,key,tag_name)
local t = ""
local name = "æIndex_table"
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local cs = string.format("%s%s",t,name)
local f = db.indexes_pool[cs]
local k = type(key)
if f and f.file and k == "string" then
local fl = f.file
if f.needs_flushing == true then
fl:flush()
end
db.indexes_pool[cs].needs_flushing = true
db.indexes_pool[cs].inuse = true
fl:seek("end")
fl:write(string.format("\n%s",key))
fl:seek("set")
local count = tonumber(fl:read("*l"))
count = count + 1
fl:seek("set")
fl:write(string.format("%i",count))
elseif f and f.file then
local fl = f.file
if f.needs_flushing == true then
fl:flush()
end
db.indexes_pool[cs].needs_flushing = true
db.indexes_pool[cs].inuse = true
local c = 0
for i in pairs(key) do
fl:seek("end")
fl:write(string.format("\n%s",i))
c = c + 1
end
fl:seek("set")
local count = tonumber(fl:read("*l"))
count = count + c
fl:seek("set")
fl:write(string.format("%i",count))
else
return false
end
end
function colddb.get_count(db,tag_name)
local t = ""
local name = "æIndex_table"
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local cs = string.format("%s%s",t,name)
local f = db.indexes_pool[cs]
if f and f.file then
local fl = f.file
if f.needs_flushing == true then
fl:flush()
f.needs_flushing = true
end
fl:seek("set")
local count = tonumber(fl:read("*l"))
db.indexes_pool[cs].inuse = true
return count
end
return nil
end
local function iterate(db,func_on_iterate,end_func,cycles_per_tick,count,cs,args)
local f = db.indexes_pool[cs]
f.inuse = true
local fl = f.file
for i=1,cycles_per_tick do
if count < 1 then
break
end
local line = fl:read("*l")
if args.do_not_skip_removed_items or not db.indexes_pool[cs].deleted_items[line] then
func_on_iterate(line,i,args)
end
count = count - 1
end
db.indexes_pool[cs] = f
if count < 1 then
if end_func then
end_func(args)
end
if db.iterate_queue[cs] and db.iterate_queue[cs][1] then
local copy = db.iterate_queue[cs][1]
if copy.begin_func then
local a = copy.begin_func(copy.args)
if a and type(a) == "table" then
copy.args = a
end
end
minetest.after(0,iterate,copy.db,copy.func_on_iterate,copy.end_func,copy.cycles_per_tick,copy.count,copy.cs,copy.args)
table.remove(db.iterate_queue[cs],1)
return true
else
db.iterate_queue[cs] = nil
end
db.indexes_pool[cs].iterating = false
return true
end
minetest.after(0,iterate,db,func_on_iterate,end_func,cycles_per_tick,count,cs,args)
end
function colddb.iterate_index_table(db,begin_func,func_on_iterate,end_func,cycles_per_tick,args,tag_name)
local t = ""
local name = "æIndex_table"
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local cs = string.format("%s%s",t,name)
local f = db.indexes_pool[cs]
if not f or not f.file then
colddb.open_index_table(db,tag_name)
f = db.indexes_pool[cs]
end
if f and f.file and db.indexes_pool[cs].iterating == false then
-- set inuse and iterating to true
db.indexes_pool[cs].inuse = true
db.indexes_pool[cs].iterating = true
local fl = f.file
if f.needs_flushing == true then
fl:flush()
f.needs_flushing = true
end
-- Get count
fl:seek("set")
local c = tonumber(fl:read("*l"))
if c < 1 then
-- If theres nothing to index then return
return false
end
if not args then
args = {}
end
args.count = c
-- Run the begin function
if begin_func then
local a = begin_func(args)
if a and type(a) == "table" then
args = a
end
end
-- Start iterating the index table
iterate(db,func_on_iterate,end_func,cycles_per_tick,c,cs,args)
elseif f and f.file then
-- If its iterating some other function then add this one to the queue list
fl:seek("set")
local c = tonumber(fl:read("*l"))
if c < 1 then
-- If theres nothing to index then return
return false
end
if not db.iterate_queue[cs] then
db.iterate_queue[cs] = {}
end
local _table = {db=db,begin_func=begin_func,func_on_iterate=func_on_iterate,end_func=end_func,cycles_per_tick=cycles_per_tick,count=c,cs=cs,tag_name=tag_name,args=args}
table.insert(db.iterate_queue[cs],_table)
end
end
local function check_use(db,name,tag_name,d)
if not d then
d = 0
end
local delay = 30 + d
local t = ""
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local cs = string.format("%s%s",t,name)
if not db.mem_pool or not db.mem_pool[cs] then
return false
end
if db.mem_pool[cs].inuse == false then
if db.mem_pool[cs].indexes == true then
local cs2 = string.format("%s%s",t,"æIndex_table")
local fs = db.indexes_pool[cs2]
if fs and fs.file then
if fs.inuse == true or fs.iterating == true then
db.indexes_pool[cs2].inuse = false
minetest.after(delay,check_use,name,tag_name,delay,d)
return false
else
fs.file:close()
db.indexes_pool[cs2] = nil
end
end
end
db.mem_pool[cs] = nil
else
db.mem_pool[cs].inuse = false
minetest.after(delay,check_use,name,tag_name,delay,d)
return false
end
end
local function load_into_mem(db,name,_table,tag_name)
if db.add_to_mem_pool then
local t = ""
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local cs = string.format("%s%s",t,name)
if not db.mem_pool[cs] then
db.mem_pool[cs] = {mem = {},inuse = false,check_timer = false,indexes = db.indexes}
end
db.mem_pool[cs].mem = _table
if not db.mem_pool[cs].check_timer then
db.mem_pool[cs].inuse = false
db.mem_pool[cs].indexes = db.indexes
db.mem_pool[cs].check_timer = true
check_use(db,name,tag_name)
end
end
end
function colddb.set(db,name,_table,tag_name)
local t = ""
if tag_name then
t = colddb.get_tag(db,tag_name)
end
if db.indexes and not colddb.file_Exists(db,name,tag_name) then
local cs2 = string.format("%s%s",t,"æIndex_table")
local om = db.indexes_pool[cs2]
if not colddb.file_Exists(db,"æIndex_table",tag_name) or not (om and om.file) then
colddb.open_index_table(db,tag_name)
end
minetest.after(0,function(db,name,tag_name)colddb.append_index_table(db,name,tag_name)end,db,name,tag_name)
end
minetest.after(1,function(db,name, _table,tag_name)colddb.save_table(db,name, _table,tag_name)end,db,name, _table,tag_name)
local cs = string.format("%s%s",t,name)
if db.add_to_mem_pool and not (db.mem_pool or db.mem_pool[cs]) then
db.mem_pool[cs] = {mem = {},inuse = false,check_timer = false,indexes = db.indexes}
load_into_mem(db,name,_table,tag_name)
end
end
function colddb.set_key(db,name,tag_name)
local t = ""
if tag_name then
t = colddb.get_tag(db,tag_name)
end
if db.indexes and not colddb.file_Exists(db,name,tag_name) then
local cs2 = string.format("%s%s",t,"æIndex_table")
local om = db.indexes_pool[cs2]
if not colddb.file_Exists(db,"æIndex_table",tag_name) or not (om and om.file) then
colddb.open_index_table(db,tag_name)
end
minetest.after(0,function(db,name,tag_name)colddb.append_index_table(db,name,tag_name)end,db,name,tag_name)
end
minetest.after(1,function(db,name, tag_name)colddb.save_key(db,name, tag_name)end,db,name, tag_name)
local cs = string.format("%s%s",t,name)
if db.add_to_mem_pool and not (db.mem_pool or db.mem_pool[cs]) then
db.mem_pool[cs] = {mem = {},inuse = false,check_timer = false,indexes = db.indexes}
load_into_mem(db,name,_table,tag_name)
end
end
function colddb.get(db,name,tag_name)
local t = ""
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local cs = string.format("%s%s",t,name)
local pm = db.mem_pool[cs]
if pm then
db.mem_pool[cs].inuse = true
return pm.mem
else
local _table = colddb.load_table(db,name,tag_name)
if _table then
load_into_mem(db,name,_table,tag_name)
return _table
end
end
return nil
end
function colddb.get_key(db,name,tag_name)
local t = ""
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local cs = string.format("%s%s",t,name)
local pm = db.mem_pool[cs]
if pm then
db.mem_pool[cs].inuse = true
return true
else
local bool = colddb.load_key(db,name,tag_name)
if bool then
load_into_mem(db,name,bool,tag_name)
return bool
end
end
return nil
end
function colddb.remove(db,name,tag_name)
local t = ""
if tag_name then
t = colddb.get_tag(db,tag_name)
end
local cs = string.format("%s%s",t,name)
if db.mem_pool and db.mem_pool[cs] then
db.mem_pool[cs] = nil
end
if db.indexes and colddb.file_Exists(db,"æIndex_table",tag_name) then
local cs2 = string.format("%s%s",t,"æIndex_table")
local om = db.indexes_pool[cs2]
if not om and not om.file then
colddb.open_index_table(db,tag_name)
end
colddb.delete_lines(db,name,tag_name)
end
minetest.after(0,function(db,name,tag_name)colddb.delete_file(db,name,tag_name)end,db,name,tag_name)
end

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db/.gitignore vendored
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# Ignore everything in this directory
*
# Except this file
!.gitignore

0
depends.txt Normal file
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1
description.txt Normal file
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pure lua No-sql database mod.

86
flatdb.lua
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local mp = require("MessagePack")
local function isFile(path)
local f = io.open(path, "r")
if f then
f:close()
return true
end
return false
end
local function isDir(path)
path = string.gsub(path.."/", "//", "/")
local ok, err, code = os.rename(path, path)
if ok or code == 13 then
return true
end
return false
end
local function load_page(path)
local ret
local f = io.open(path, "rb")
if f then
ret = mp.unpack(f:read("*a"))
f:close()
end
return ret
end
local function store_page(path, page)
if type(page) == "table" then
local f = io.open(path, "wb")
if f then
f:write(mp.pack(page))
f:close()
return true
end
end
return false
end
local pool = {}
local db_funcs = {
save = function(db, p)
if p then
if type(p) == "string" and type(db[p]) == "table" then
return store_page(pool[db].."/"..p, db[p])
else
return false
end
end
for p, page in pairs(db) do
if not store_page(pool[db].."/"..p, page) then
return false
end
end
return true
end
}
local mt = {
__index = function(db, k)
if db_funcs[k] then return db_funcs[k] end
if isFile(pool[db].."/"..k) then
db[k] = load_page(pool[db].."/"..k)
end
return rawget(db, k)
end
}
pool.hack = db_funcs
return setmetatable(pool, {
__mode = "kv",
__call = function(pool, path)
assert(isDir(path), path.." is not a directory.")
if pool[path] then return pool[path] end
local db = {}
setmetatable(db, mt)
pool[path] = db
pool[db] = path
return db
end
})

8
init.lua Normal file
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@ -0,0 +1,8 @@
modpath = minetest.get_modpath("colddb")
local ie = minetest.request_insecure_environment()
if ie then
loadfile(modpath .. "/colddb.lua")(ie)
else
dofile(modpath .. "/colddb.lua")
end

1
mod.conf Normal file
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@ -0,0 +1 @@
name = colddb