tasks

type DatastoreTaskable interface {
	Taskable
	SetDatastore(ds datastore.Datastore)
}

type NewTaskFunc func() Taskable

type Progress struct {
	Percent float32 `json:"percent"`         // percent complete between 0.0 & 1.0
	Step    int     `json:"step"`            // current Step
	Steps   int     `json:"steps"`           // number of Steps in the task
	Status  string  `json:"status"`          // status string that describes what is currently happening
	Done    bool    `json:"done"`            // complete flag
	Dest    string  `json:"dest"`            // place for sending users, could be a url, could be a relative path
	Error   error   `json:"error,omitempty"` // error message
}

type Task struct {
	// uuid identifier for task
	Id string `json:"id"`
	// created date rounded to secounds
	Created time.Time `json:"created"`
	// updated date rounded to secounds
	Updated time.Time `json:"updated"`
	// human-readable title for the task, meant to be descriptive & varied
	Title string `json:"title"`
	// id of user that submitted this task
	UserId string `json:"userId"`
	// Type of task to be executed
	Type string `json:"type"`
	// parameters supplied to the task, should be json bytes
	Params map[string]interface{} `json:"params"`
	// Status Message
	Status string `json:"status,omitempty"`
	// Error Message
	Error string `json:"error,omitempty"`
	// timstamp for when request was added to the tasks queue
	// nil if request hasn't been sent to the queue
	Enqueued *time.Time `json:"enqueued,omitempty"`
	// timestamp for when the task was removed from the queue
	// and started, nil if the request hasn't been started
	Started *time.Time `json:"started,omitempty"`
	// timestamp for when request succeeded
	// nil if task hasn't succeeded
	Succeeded *time.Time `json:"succeeded,omitempty"`
	// timestamp for when request failed
	// nil if task hasn't failed
	Failed *time.Time `json:"failed,omitempty"`
	// progress of this task's completion
	// progress may not be stored, but instead kept ephemerally
	Progress *Progress `json:"progress,omitempty"`
}

type TaskRequests struct {
	// url to amqp server for enqueuing tasks, only required
	// to fullfill requests, not submit them
	AmqpUrl string
	// Store to read / write tasks to only required
	// to fulfill requests, not submit them
	Store datastore.Datastore
}

type Taskable interface {
	// are these task params valid? return error if not
	// this func will be called before adding the task to
	// the queue, and won't be added on failure.
	Valid() error
	// Do the task, returning incremental progress updates
	// it's expected that the func will send either
	// p.Done == true or p.Error != nil at least once
	// to signal that the task is either done or errored
	Do(updates chan Progress)
}

type TasksEnqueueParams struct {
	// Title of the task
	// Requesters should generate their own task title for now
	// tasks currently have no way of generating a sensible default title
	Title string
	// Type of task to perform
	Type string
	// User that initiated the request
	UserId string
	// Parameters to feed to the task
	Params map[string]interface{}
}

type TasksGetParams struct {
	Id string
}

type TasksListParams struct {
	OrderBy string
	Limit   int
	Offset  int
}