pgstore

Documentation

Overview

Package pgstore is a PostgreSQL-based session store for the SCS session package.

A working PostgreSQL database is required, containing a sessions table with the definition:

CREATE TABLE sessions (
  token TEXT PRIMARY KEY,
  data BYTEA NOT NULL,
  expiry TIMESTAMPTZ NOT NULL
);
CREATE INDEX sessions_expiry_idx ON sessions (expiry);

The pgstore package provides a background 'cleanup' goroutine to delete expired session data. This stops the database table from holding on to invalid sessions indefinitely and growing unnecessarily large.

Index

• type PGStore
  • func New(db *sql.DB, cleanupInterval time.Duration) *PGStore
  • func (p *PGStore) Delete(token string) error
  • func (p *PGStore) Find(token string) (b []byte, exists bool, err error)
  • func (p *PGStore) Save(token string, b []byte, expiry time.Time) error
  • func (p *PGStore) StopCleanup()

Types

type PGStore

type PGStore struct {
	*sql.DB
	// contains filtered or unexported fields
}

PGStore represents the currently configured session session store.

func New

func New(db *sql.DB, cleanupInterval time.Duration) *PGStore

New returns a new PGStore instance.

The cleanupInterval parameter controls how frequently expired session data is removed by the background cleanup goroutine. Setting it to 0 prevents the cleanup goroutine from running (i.e. expired sessions will not be removed).

func (*PGStore) Delete

func (p *PGStore) Delete(token string) error

Delete removes a session token and corresponding data from the PGStore instance.

func (*PGStore) Find

func (p *PGStore) Find(token string) (b []byte, exists bool, err error)

Find returns the data for a given session token from the PGStore instance. If the session token is not found or is expired, the returned exists flag will be set to false.

func (*PGStore) Save

func (p *PGStore) Save(token string, b []byte, expiry time.Time) error

Save adds a session token and data to the PGStore instance with the given expiry time. If the session token already exists then the data and expiry time are updated.

func (*PGStore) StopCleanup

func (p *PGStore) StopCleanup()

StopCleanup terminates the background cleanup goroutine for the PGStore instance. It's rare to terminate this; generally PGStore instances and their cleanup goroutines are intended to be long-lived and run for the lifetime of your application.

There may be occasions though when your use of the PGStore is transient. An example is creating a new PGStore instance in a test function. In this scenario, the cleanup goroutine (which will run forever) will prevent the PGStore object from being garbage collected even after the test function has finished. You can prevent this by manually calling StopCleanup.