fortune-postgres

Fortune Postgres Adapter

This is a Postgres adapter for Fortune which makes use of specific Postgres functionality. Key features include:

• Non-destructive table setup: it will create tables and columns automatically upon connection, but will not alter columns. Data migrations are not handled by this adapter.
• Emulates array foreign keys: this adapter will not create junction tables, but instead create array columns, which is much faster than joins but lacks a database-level foreign key constraint, this is delegated to Fortune.
• SQL query building: it interprets arguments from Fortune's adapter interface directly, and generates optimized queries.

To use this adapter, the database user must be setup prior to attempting to connect, or the default postgres user can be used.

This adapter, along with Fortune.js, does not implement ORM. This adapter sets up tables, and translates the adapter interface directly into SQL statements. It is a plain query builder for Postgres.

Requirements

• Postgres version 9.4 or newer. Older versions are untested and will not work.

Usage

Install the fortune-postgres package from npm:

$ npm install fortune-postgres

Then use it with Fortune:

const fortune = require('fortune')
const postgresAdapter = require('fortune-postgres')

const store = fortune({ ... }, {
  adapter: [
    postgresAdapter,
    {
      // options object, URL is mandatory.
      url: `postgres://${username}:${password}@${host}:${port}/${db}`
    }
  ]
})

Options

• url: Connection URL string. Required if no other connection options are given. Add the query param ssl=true to enable SSL.
• connection: Connection object, see documentation. This takes precendence over the URL. Optional.
• pool: an instance of node-pg-pool can be passed in directly. This takes precendence over all connection settings. Optional.
• isNative: Whether or not to use native bindings, requires pg-native module, which is an optional dependency of this one. Default: false.
• typeMap: an object keyed by type name and valued by table name.
• primaryKeyType: Data type of the primary key. May be String, Number, or a string for custom type. Default: String.
• generatePrimaryKey: A function that accepts one argument, the type of the record, and returns either a String or Number. By default, it returns 15 random bytes, base64 encoded in a URI-safe way. Set this to a falsey value like null to turn this off.
• useForeignKeys: Whether or not to use foreign key constraint, optional since it will only be applied to non-array fields. Default: false.

Extension

The query field for the options object should be a function that accepts two arguments, the prepared SQL query and parameters, and returns an SQL query.

SSL

SSL can be enabled by adding ssl=true as a query parameter the database URL (e.g. postgres://postgres@localhost:5432/app_db?ssl=true). If using the connection object, add an ssl property with the value true.

Internal Usage

The database client pool is exposed as the pool property on the adapter instance, so for example, store.adapter.pool (or the alias store.adapter.client) lets you use the Postgres driver directly. This should be considered private since it is provided by the underlying implementation node-pg-pool, and is exposed for the sake of transparency.

For more on the API of the pool object, refer to the node-pg-pool documentation.

License

This software is licensed under the MIT License.