Awesome

lua-resty-orm

Simple ORM for openresty

Status

This library is NOT production ready. PostgreSql driver wasn't tested.

Usage

example:

local orm = require'orm'.open{
  driver = 'mysql', -- or 'postgresql'
  port = 3306,
  host = '127.0.0.1',
  user = 'root',
  password = '123456',
  database = 'test',
  charset = 'utf8mb4',
  expires = 100,  -- cache expires time
  debug = true -- log sql with ngx.log 
}

-- Mapper is the main feature of this library: 
-- MySQL: select `name`, `age` from `users` where id > 10 limit 20
local res, err = orm.mapper:prepare("select [name], [age] from [users] where id > ?d", 10):append("limit ?d", 20):query()
-- you can chain call any method, and handle errors at the end
-- when error occured, any chained calls will be ignored
if err then 
	ngx.say(res.err)
else
	ngx.say(cjson.encode(res))
end

placeholders

placeholders can be used is sql, and will be converted to the right value for every supported driver or error on failed.

- `?t`  table  {1,2,'a'} => 1,2,'a'
- `?i`  
- `?b`  bool(0, 1), only false or nil will be converted to 0 for mysql, TRUE | FALSE in postgresql
- `?e`  expression: MAX(id) | MIN(id) ...
- `?d`  digit number, convert by tonumber
- `?n`  NULL, false and nil wil be converted to 'NULL', orther 'NOT NULL'
- `?s`  string, escaped by ngx.quote\_sql\_str
- `?`   any, convert by guessing the value type

orm.transaction(fn)

run fn in transaction:

orm.transaction(function(conn)
    -- any mapper query
end)

Notice: transaction can't be nested now. maybe won't be fixed.

mapper_instance, err = mapper:prepare(sql, ...)

prepare sql statement and convert any parameters.

• mapper_instance lua table support most of the features
• err true/false

res, err = mapper_instance:append(sql, ...)

like prepare, just append another more sql statement

sql = mapper_instance:tosql()

return generated sql string

res, err = mapper_instance:query()

send sql to database and return the resultset or return error

• res error or resultset
• err true/false

res, err = mapper_instance:first()

get first record from resultset

res, err = mapper_instance:scalar()

get first row and first column of the resultset, handy on getting aggrating result, eg: count(*), max(id)...