☯ knex-schemer
knex-schemer
is a tool that allows you to define a database schema in JSON
using Knex-Schemer Definition Format or KSDF
and create/update/delete that schema using basic transactional functions. This approach allows you to re-use and extend the schema definition in different parts of your application. It also allows you to create and update database tables quickly. As named, the tool requires a knex
instance to operate
- See the
WIKI
for full documentation - And the
Change Log
for what's new!
Documentation
API
schemer.convert
( data
, schema
)
removes data columns and tables that do not exist in the schema and returns a converted data object
schemer.convertAndLoad
( data
, schema
, [transaction
] )
data
Object
- Data to convertschema
Object
- Database schema object- [
transaction
]Transaction
- transaction to use
converts the data object and loads the data into the database
schemer.drop
( schema
, [transaction
] )
schema
Object
- Database schema object- [
transaction
]Transaction
- transaction to use
drops all tables defined in the schema object
schemer.sync
( schema
, [transaction
] )
schema
Object
- Database schema object- [
transaction
]Transaction
- transaction to use
creates the tables defined in the schema object if they do not exist. If the tables do exist, the row definitions are updated to reflect the schema object. Table alteration is limited to what is supported by knex.js
schemer.dump
( options
)
options
Object
- Hash of options or a schema object
dumps database data into a data object that can be used by schemer.load()
Examples
Full define, drop, create, and load example
Defines a schema and dataset, then drops any existing tables, creates them, and loads the data
// require the module
var schemer = require('knex-schemer')(knex);
var types = schemer.constants.types;
// create a schema
var schema = {
user: {
id: { type: type.integer, primary: true, increments: true },
name: { type: type.string },
username: { type: type.string, size: 32 },
email: { type: type.string }
},
credential: {
id: { type: type.integer, primary: true, increments: true },
name: { type: type.string },
username: { type: type.string },
encryptedKey: { type: type.string }
}
};
// define data to load
var data = {
user: [
{
id: 1,
name: 'Jack Shepard',
username: 'jshepard',
email: 'thechosenone@theisland.org'
},
{
id: 2,
name: 'Kate Austen',
username: 'kausten',
email: 'kateplusfate@theisland.org'
}
],
credential: [
{
id: 1,
name: 'swan',
username: 'operator',
encryptedKey: '4815162342'
}
]
};
// drop all tables
schemer.drop(schema).then(function() {
// create or update all tables
return schemer.sync(schema).then(function() {
// convert and load the data
return schemer.convertAndLoad(data, schema).then(function() {
// post load operations
});
});
});
Full transactional drop, create, and load example
Borrowing the schema and data from the first example, the operations can share the same transaction using knex.transaction()
// create a knex transaction
knex.transaction(function(trx) {
// pass the transaction as the last argument in each method
schemer.drop(schema, trx).then(function() {
return schemer.sync(schema, trx).then(function(result) {
return schemer.convertAndLoad(data, schema, trx);
});
});
})
.then(function() {
// do something on success
})
.catch(function(e) {
// do something on error
});