一個自用的極簡 ORM,帶三方緩存支持——Toshihiko

jopen 9年前發布 | 9K 次閱讀 持久層框架

目前花瓣網和大搜車都有項目在用該 ORM。

使用很簡單,且在上層沒做類似于 group byjoin 等降低效率的 API 支持,因為 mysql 本身效率就不是特別高。

支持三方緩存——比如 memcached,也可以自己實現一個 toshihiko-xxx 作為自己的緩存層。

Repo 地址在:https://github.com/XadillaX/Toshihiko

具體用法看文檔。


A simple ORM for node.js in Huaban with :heart:. For performance, this ORM does not provide operations like in, group by, join and so on.

Installation

$ npm install toshihiko

Document

Initialize

You should create a Toshihiko object to connect to MySQL:

var T = require("toshihiko");
var toshihiko = new T.Toshihiko(database, username, password, options);

Options can include these things:

  • host: hostname or IP of MySQL. Defaults to localhost.
  • port: port of MySQL. Defaults to 3306.
  • cache: if you want to cache support, let it be an cache layer object or cache layer configuration which will be mentioned below. Defaults to undefined.
  • etc… (All options in module mysql will be OK)

Cache

Toshihiko now is using new cache layer! You can choose your cache layer by your self!

Pass an object to cache of options like:

var toshihiko = new T.Toshihiko(database, username, password, {
    cache: YOUR_CACHE_LAYER
});

The YOUR_CACHE_LAYER may be an instance of Toshihiko cache layer object like toshihiko-memcacehd (you can implement a cache layer by yourself).

What’s more, YOUR_CACHE_LAYER may be a configuration object which should include name or path.

For an example,

var toshihiko = new T.Toshihiko(database, username, password, {
    cache: {
        name: "memcached",
        servers: "...",
        options: {}
    }
});

will search for package toshihiko-memcached and pass servers, options to create a toshihiko-memcached object. By default, Toshihiko support memcached as cache layer by using package toshihiko-memcacehd.

You can get the cache object in Toshihiko by getting the variable:

var cache = toshihiko.cache;

Define a Model

Define a model schema:

var Model = toshihiko.define(tableName, [
    { name: "key1", column: "key_one", primaryKey: true, type: Toshihiko.Type.Integer },
    { name: "key2", type: Toshihiko.Type.String, defaultValue: "Ha~" },
    { name: "key3", type: Toshihiko.Type.Json, defaultValue: [] },
    { name: "key4", validators: [
        function(v) {
            if(v > 100) return "`key4` can't be greater than 100";
        },
        function(v) {
            // blahblah...
        }
    ] },
    { name: "key5", type: Toshihiko.Type.String, allowNull: true }
], options);

You can add extra model functions by yourself:

Model.sayHello = function() {
    this.find(function(err, rows) {
        console.log(err);
        console.log(rows);
    });
};

options is optional. You can specify Memcached here if you haven’t defined it in Toshihiko. Otherwise, you can let it be null when you don’t want to use Memcached in this Model but you had specify it in Toshihiko.

Query & Update

Toshihiko uses chain operations. Eg:

Model.where(condition).limit(limit).orderBy(order).find(callback);
Model.where(condition).limit(limit).delete(callback);
Model.findById(primaryKeysId, callback);
Model.where(condition).update(data, callback);

where

condition is an JSON object with keys:

  • A field name
  • $and
  • $or
Field Name
Value

For field name, the value can be a certain value. Eg:

{
    key1: 1
}
Operators

The value can be a JSON object with comparison operators $eq / ===, $neq / !==, $gt(e) / >(=), $lt(e) / <(=), $like.

Eg:

{
    keys1: {
        $neq: value
    }
}

value can be a certain value or an array with logic AND.

Eg. $neq: 5 or $neq: [ 5, 2 ].

Logic

You can use logic symbols as well:

{
    keys1: {
        $or: {
            $eq: 1,
            $neq: 2
        }
    }
}

Notice: you can define logic and operators with many many levels.

$and And $or

You can use these two logic with many many levels.

{
    $or: {
        $or: { $or: ... },
    }
}

And the last level can be like that:

{
    $and: {
        KEY: { REFER TO ABOVE `Field Name` }
    }
}

limit

For examples:

foo.limit("1");         ///< skip 1
foo.limit("0,30");      ///< skip 0, limit 30
foo.limit([ 0, 30 ]);   ///< skip 0, limit 30
foo.limit([ 1 ]);       ///< skip 1
foo.limit({ skip: 0, limit: 1 });   ///< skip 0, limit 1
foo.limit({ skip: 1 }); ///< skip 1
foo.limit({ limit: 1 });///< limit 1

orderBy

For examples:

foo.orderBy("key1 asc");
foo.orderBy([ "key1 asc", "key2 desc" ]);
foo.orderBy({ key1: "asc", key2: "desc", key3: 1, key4: -1 });

count

Count the records with a certain condition:

foo.where(condition).count(function(err, count) {});

find

With the conditions, limit and orders to find all records:

foo.where(condition).find(function(err, rows) {
    //...
}, withJson);

Notice: the parameter withJson is an optional parameter. If it’s true, elements in rows are JSON objects. Otherwise, they are all Yukari objects.

findOne

It’s similar with find, but it will just find only one record.

foo.where(condition).findOne(function(err, row) {
    //...
}, withJson);

Notice: withJson is the same as above.

findById

foo.findById(primaryKeysId, function(err, bar) {
}, withJson);

primaryKeysId can be a string or an object.

When there’re several primary keys in one table, this value may be like:

{
    key1: 1,
    key2: 2,
}

If there’s only one primary key, you can just pass a string, number or some other base type value.

For examples:

foo.findById({ key1: 1, key2: 2 }, callback);
foo.findById(1, callback);

update

foo.where(condition).update(data, function(err, result) {});

data is an object that includes your changed data. Eg:

{
    key1: 12,
    key2: "123",
    key3: "{{key3 + 1}}"
}

String with {{...}} will be parsed as SQL statement. For example, you can let it be {{CONCAT(`key3`, ".suffix")}} or any others statement you want to use.

Notice: result is something like:

{ fieldCount: 0,
  affectedRows: 1,
  insertId: 0,
  serverStatus: 2,
  warningCount: 0,
  message: '(Rows matched: 1  Changed: 1  Warnings: 0',
  protocol41: true,
  changedRows: 1 }

delete

foo.where(condition).delete(function(err, result) { /** ... */ });

┏ (゜ω゜)=? Promise-Liked

For find, findOne, findById, update and delete, you can use it without callback function.

Whether you used callback function or not, these function will return a ResultPromisor object. You can use it like:

ResultPromisor::success
var Q = foo.find();
Q.success(function(result) { /** ... */ });
ResultPromisor::error
var Q = foo.find();
Q.error(function(err) { /** ... */ });
ResultPromisor::finished
var Q = foo.find();
Q.finished(function(err, result) { /** ... */ });

Yukari Object

Yukari object is the data entity object.

rows in Model.find(function(err, rows) {}) is an array with Yukari objects unless you use withJson parameter.

Also, you can get a new Yukari object by calling Model.build().

We assume all Yukari(s) below are created from Model.find() except Model.build().

Model.build()

You can pass a JSON object to this function to generate a new Yukari object:

Model.build({
    key1    : 1,
    key2    : 2,
    key3    : "3"
});

Yukari::toJSON()

Transform Yukari object to a simple original JSON object:

var json = yukari.toJSON();
console.log(json);

Yukari::insert()

If your Yukari object is created from Model.build(), you should use this function to insert data to database.

var yukari = Model.build({ ... });
yukari.insert(function(err, yukari) {
    //...
});

Yukari::update()

Change this Yukari data to database.

yukari.update(function(err, yukari) {
    //...
});

Notice: "{{..}}" operation is not supported here.

Yukari::save()

If it’s a new Yukari object, it will call insert. Otherwise, it will call update.

yukari.save(function(err, yukari) {
    //...
});

Yukari::delete()

Delete this record from database.

yukari.delete(function(err, affectedRows) {});

Custom Field Type

There’re 4 kind of types in Toshihiko as default.

  • Type.Float
  • Type.Integer
  • Type.Json
  • Type.String

You can code a custom field type by yourself.

Here’s the template:

var Type = {};
Type.name = "type";
Type.needQuotes = false;    ///< Is this type need quotes in SQL statement?
Type.restore = function(v) {
    // v is a parsed value,
    // you should transform
    // it to the type that
    // SQL can recognize
    return v;
};
Type.parse = function(v) {
    // v is a original value,
    // you should parse it
    // into your own type
    return v;
};
Type.defaultValue = 0.1;    ///< Default value

You can refers to lib/fieldType/json.js to get more information.

Contribute

You’re welcome to pull requests!

Thanks to:

「雖然我覺得不怎麼可能有人會關注我」

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