seneca-postgres-store

Seneca data store plugin for PostgreSQL

A Seneca.js data storage plugin

seneca-postgres-store

seneca-postgres-store is a PostgreSQL database plugin for the Seneca MVP toolkit. The plugin is using the node-postgres driver.

Usage:

var seneca = require('seneca');
var store = require('seneca-postgres-store');

var config = {}
var storeopts = {
  name:'dbname',
  host:'127.0.0.1',
  port:5432,
  username:'user',
  password:'password',
  nolimit: true
};

...

var si = seneca(config)
si.use(store, storeopts)
si.ready(function() {
  var product = si.make('product')
  ...
})
...

You don't use this module directly. It provides an underlying data storage engine for the Seneca entity API:

var entity = seneca.make$('typename')
entity.someproperty = "something"
entity.anotherproperty = 100
 
entity.save$(function (errentity) { ... })
entity.load$({id: ...}, function (errentity) { ... })
entity.list$({property: ...}, function (errentity) { ... })
entity.remove$({id: ...}, function (errentity) { ... })

The standard Seneca query format is supported:

  • .list$({f1:v1, f2:v2, ...}) implies pseudo-query f1==v1 AND f2==v2, ....

  • .list$({f1:v1, ...}, {sort$:{field1:1}}) means sort by f1, ascending.

  • .list$({f1:v1, ...}, {sort$:{field1:-1}}) means sort by f1, descending.

  • .list$({f1:v1, ...}, {limit$:10}) means only return 10 results.

  • .list$({f1:v1, ...}, {skip$:5}) means skip the first 5.

  • .list$({f1:v1,...}, {fields$:['fd1','f2']}) means only return the listed fields.

This includes support for more complex queries.

Starting from version version 1.x.x list$ supports also these comparison operators:

  • ne$: .list$({ f1: {ne$: v1} }) for not-equal.
  • eq$: .list$({ f1: {eq$: v1} }) for equal.
  • lte$: .list$({ f1: {lte$: 5} }) for less than or equal.
  • lt$: .list$({ f1: {lt$: 5} }) for less than.
  • gte$: .list$({ f1: {gte$: 5} }) for greater than or equal.
  • gt$: .list$({ f1: {gt$: 5} }) for greater than.
  • in$: .list$({ f1: {in$: [10, 20]} }) for in. in$ operator accepts only values of type array.
  • nin$: .list$({ f1: {nin$: ['v1', 'v2']} }) for not-in. nin$ operator accepts only values of type array.

Note: you can use sort$, limit$, skip$ and fields$ together.

Note: you can use any operators described above together.

Starting from version version 1.1.x list$ supports also these logical operators:

  • or$: .list$({ or$: [{name: 'something'}, {price: 200}]})
  • and$: .list$({ and$: [{name: 'something'}, {price: 200}]})

Note: These logical operators accepts only arrays as values.

Note: These operators can be used together to build more complex queries

Note: These logical operators can be used also with any Comparison query operators described above.

Note: A complex example:

ent.list$( 
  { 
    or$: [
      {name: 'something'}, 
      {
        and$: [
          {price: {gte$: 100}}, 
          {name: 'other'}
        ]
      }, 
      {color: { ne$: 'red' }}
    ], 
    sort$: {name: 1},
    fields$: ['name', 'color']
  }, function(errlist){
    // do something with result... 
  } )

By default queries are limited to 20 values. This can be bypassed by passing the nolimit option, which if set to true will not limit any queries.

To filter the fields returned from the list operation, pass a fields$ array of column names to return. If no fields$ are passed, all fields are returned (i.e. select * is used). e.g.

query.fields$ = ['id', 'name']

Note: The implicit id that is generated on save$ has uuid value. To override this you must provide entity.id$ with a desired value.

As with all seneca stores, you can access the native driver, in this case, the pg connection object using entity.native$(function (err, connectionPool, release) {...}). Please make sure that you release the connection after using it.

entity.native$( function (err, client, releaseConnection){
  // ... you can use client
  // ... then release connection
  releaseConnection()
} )

We encourage participation. If you feel you can help in any way, be it with examples, extra testing, or new features please get in touch.