postgres

Documentation

Index

• Constants
• func AssertRetentionSchedule(ctx context.Context, db *sql.DB, queueName string, taskType queue.TaskType, ...) (err error)
• func AssertRetentionScheduleWithSpec(ctx context.Context, db *sql.DB, spec RetentionTaskSpec) (err error)
• func NewDequeuer(db *sql.DB, dbListener *pq.Listener, cfg config.Queue) queue.Dequeuer
• func NewDequeuerWithMetrics(db *sql.DB, dbListener *pq.Listener, cfg config.Queue) queue.Dequeuer
• func NewQueuer(db *sql.DB) queue.Queuer
• func NewQueuerWithMetrics(db *sql.DB) queue.Queuer
• func NewRetentionHandler(db *sql.DB) queue.TaskHandler
• func NewScheduler(db *sql.DB) queue.Scheduler
• func NewSchedulerWithMetrics(db *sql.DB) queue.Scheduler
• func SetupTables(ctx context.Context, db db.SQLDB, references []ForeignReference) (err error)
• type ForeignReference
• type RetentionTaskSpec

Constants

const (
	// MaintenanceTaskQueue task queue name used for all the periodic maintenance jobs.
	// These are internal queue internal tasks
	MaintenanceTaskQueue string = "queue-maintenance"

	// RetentionTask is finished task cleanup type
	RetentionTask queue.TaskType = "retention"
)

const (
	// TasksTable is the name of the Postgres table that is used for tasks
	TasksTable = "tasks"
	// SchedulesTable is the name of the Postgres table used for schedules
	SchedulesTable = "schedules"
)

Functions

func AssertRetentionSchedule

func AssertRetentionSchedule(ctx context.Context, db *sql.DB, queueName string, taskType queue.TaskType, status queue.TaskStatus, age time.Duration) (err error)

AssertRetentionSchedule creates a new queue retention tasks for the supplied queue, finished tasks matching the supplied parameters will be deleted

func AssertRetentionScheduleWithSpec

func AssertRetentionScheduleWithSpec(ctx context.Context, db *sql.DB, spec RetentionTaskSpec) (err error)

AssertRetentionScheduleWithSpec ensures that a queue retention tasks exists with the provided task spec. The task is scheduled for a random minute throughout the hour. Use AssertRetentionSchedule to create simple retention tasks based on queue, type, and age. Callers should only use AssertRetentionScheduleWithSpec when the retention policy by age is not accurate enough for their needs.

An upsert pattern is used to ensure that this retention task is scheduled exactly once.

func NewDequeuer

func NewDequeuer(db *sql.DB, dbListener *pq.Listener, cfg config.Queue) queue.Dequeuer

NewDequeuer creates a new postgres queue dequeuer

func NewDequeuerWithMetrics

func NewDequeuerWithMetrics(db *sql.DB, dbListener *pq.Listener, cfg config.Queue) queue.Dequeuer

NewDequeuerWithMetrics creates a new postgres queue dequeuer with the default metrics enabled

func NewQueuer

func NewQueuer(db *sql.DB) queue.Queuer

NewQueuer creates a new postgres queue queuer

func NewQueuerWithMetrics

func NewQueuerWithMetrics(db *sql.DB) queue.Queuer

NewQueuerWithMetrics creates a new postgres queue queuer with metrics enabled

func NewRetentionHandler

func NewRetentionHandler(db *sql.DB) queue.TaskHandler

NewRetentionHandler creates a task handler that will clean up old finished tasks

func NewScheduler

func NewScheduler(db *sql.DB) queue.Scheduler

NewScheduler creates a new postgres task scheduler

func NewSchedulerWithMetrics

func NewSchedulerWithMetrics(db *sql.DB) queue.Scheduler

NewScheduler creates a new postgres task scheduler with metrics enabled

func SetupTables

func SetupTables(ctx context.Context, db db.SQLDB, references []ForeignReference) (err error)

SetupTables sets up all the necessary tables, foreign keys and indexes.

This supports both: initial bootstrapping and changing of the reference list. However, it does not apply changes to an existing reference, this will do nothing.

Types

type ForeignReference

type ForeignReference struct {
	// ColumnName is a name of the colum in the `tasks` and `schedules` tables
	ColumnName string
	// ColumnType is a type of the colum in the `tasks` and `schedules` tables
	ColumnType string
	// ReferencedTable is a table name this column should be referencing
	ReferencedTable string
	// ReferencedColumn is a column name this column should be referencing
	ReferencedColumn string
}

ForeignReference describes a foreign key reference in the queue system

type RetentionTaskSpec

type RetentionTaskSpec struct {
	handlers.SQLExecTaskSpec
	QueueName string           `json:"queueName"`
	TaskType  queue.TaskType   `json:"taskType"`
	Status    queue.TaskStatus `json:"status"`
	Age       time.Duration    `json:"age"`
}

RetentionTaskSpec defines a SQL task to remove completed tasks that match given criteria.