executor

Documentation

Index

• Constants
• func CreateSource(ID parser.NodeID, params SourceParams, storage storage.Storage, ...) (parser.Source, *transform.Controller)
• func CreateTransform(ID parser.NodeID, params TransformParams) (transform.OpNode, *transform.Controller)
• type Engine
  • func NewEngine(store storage.Storage) *Engine
  • func (e *Engine) Close() error
  • func (e *Engine) Execute(ctx context.Context, query *storage.FetchQuery, opts *EngineOptions, ...)
• type EngineOptions
• type ExecutionState
  • func GenerateExecutionState(pplan plan.PhysicalPlan, storage storage.Storage) (*ExecutionState, error)
  • func (s *ExecutionState) Execute(ctx context.Context) error
  • func (s *ExecutionState) String() string
• type QueryStatistics
• type QueryTask
• type Result
• type ResultNode
  • func (r ResultNode) Process(ID parser.NodeID, block storage.Block) error
• type SourceParams
• type TaskStatus
  • func (t TaskStatus) String() string
• type Tracker
  • func NewTracker() *Tracker
  • func (t *Tracker) Close() error
  • func (t *Tracker) DetachQuery(qid uint64) error
  • func (t *Tracker) KillQuery(qid uint64) error
  • func (t *Tracker) Track(query storage.Query, connClosed <-chan bool) (*QueryTask, error)
• type TransformParams

Constants

const (
	// DefaultQueryTimeout is the default timeout for executing a query.
	// A value of zero will have no query timeout.
	DefaultQueryTimeout = time.Duration(0)
)

Functions

func CreateSource

func CreateSource(ID parser.NodeID, params SourceParams, storage storage.Storage, options transform.Options) (parser.Source, *transform.Controller)

CreateSource creates a source node

func CreateTransform

func CreateTransform(ID parser.NodeID, params TransformParams) (transform.OpNode, *transform.Controller)

CreateTransform creates a transform node which works on functions and contains state

Types

type Engine

type Engine struct {
	Stats *QueryStatistics
	// contains filtered or unexported fields
}

Engine executes a Query.

func NewEngine

func NewEngine(store storage.Storage) *Engine

NewEngine returns a new instance of QueryExecutor.

func (*Engine) Close

func (e *Engine) Close() error

Close kills all running queries and prevents new queries from being attached.

func (*Engine) Execute

func (e *Engine) Execute(ctx context.Context, query *storage.FetchQuery, opts *EngineOptions, closing <-chan bool, results chan *storage.QueryResult)

Execute runs the query and closes the results channel onces done

type EngineOptions

type EngineOptions struct {
	// AbortCh is a channel that signals when results are no longer desired by the caller.
	AbortCh <-chan bool
}

EngineOptions can be used to pass custom flags to engine

type ExecutionState

type ExecutionState struct {
	// contains filtered or unexported fields
}

ExecutionState represents the execution hierarchy

func GenerateExecutionState

func GenerateExecutionState(pplan plan.PhysicalPlan, storage storage.Storage) (*ExecutionState, error)

GenerateExecutionState creates an execution state from the physical plan

func (*ExecutionState) Execute

func (s *ExecutionState) Execute(ctx context.Context) error

Execute the sources in parallel and return the first error

func (*ExecutionState) String

func (s *ExecutionState) String() string

String representation of the state

type QueryStatistics

type QueryStatistics struct {
	ActiveQueries          int64
	ExecutedQueries        int64
	FinishedQueries        int64
	QueryExecutionDuration int64
}

QueryStatistics keeps statistics related to the QueryExecutor.

type QueryTask

type QueryTask struct {
	// contains filtered or unexported fields
}

QueryTask is the internal data structure for managing queries. For the public use data structure that gets returned, see QueryTask.

type Result

type Result interface {
}

Result provides the execution results

type ResultNode

type ResultNode struct {
}

ResultNode is used to provide the results to the caller from the query execution

func (ResultNode) Process

func (r ResultNode) Process(ID parser.NodeID, block storage.Block) error

Process the block

type SourceParams

type SourceParams interface {
	parser.Params
	Node(controller *transform.Controller, storage storage.Storage, options transform.Options) parser.Source
}

SourceParams are defined by sources

type TaskStatus

type TaskStatus int

TaskStatus is the status of a query task

const (
	// RunningTask is set when the task is running.
	RunningTask TaskStatus = iota

	// KilledTask is set when the task is killed, but resources are still
	// being used.
	KilledTask
)

func (TaskStatus) String

func (t TaskStatus) String() string

type Tracker

type Tracker struct {
	// Log queries if they are slower than this time.
	// If zero, slow queries will never be logged.
	LogQueriesAfter time.Duration

	// Maximum number of concurrent queries.
	MaxConcurrentQueries int
	// contains filtered or unexported fields
}

Tracker tracks the query state

func NewTracker

func NewTracker() *Tracker

NewTracker creates a new tracker.

func (*Tracker) Close

func (t *Tracker) Close() error

Close kills all running queries and prevents new queries from being attached.

func (*Tracker) DetachQuery

func (t *Tracker) DetachQuery(qid uint64) error

DetachQuery removes a query from the query table. If the query is not in the killed state, this will also close the related channel.

func (*Tracker) KillQuery

func (t *Tracker) KillQuery(qid uint64) error

KillQuery enters a query into the killed state and closes the channel from the TaskManager. This method can be used to forcefully terminate a running query.

func (*Tracker) Track

func (t *Tracker) Track(query storage.Query, connClosed <-chan bool) (*QueryTask, error)

Track is used to add a new query to tracker

type TransformParams

type TransformParams interface {
	parser.Params
	Node(controller *transform.Controller) transform.OpNode
}

TransformParams are defined by transforms