streamlog

Documentation

Overview

Package streamlog provides a non-blocking message broadcaster.

Index

• Constants
• Variables
• func ShouldEmitLog(sql string, rowsAffected, rowsReturned uint64) bool
• type Formatter
• type LogFormatter
  • func GetFormatter(logger *StreamLogger) LogFormatter
• type StreamLogger
  • func New(name string, size int) *StreamLogger
  • func (logger *StreamLogger) LogToFile(path string, logf LogFormatter) (chan interface{}, error)
  • func (logger *StreamLogger) Name() string
  • func (logger *StreamLogger) Send(message interface{})
  • func (logger *StreamLogger) ServeLogs(url string, logf LogFormatter)
  • func (logger *StreamLogger) Subscribe(name string) chan interface{}
  • func (logger *StreamLogger) Unsubscribe(ch chan interface{})

Constants

const (
	// QueryLogFormatText is the format specifier for text querylog output
	QueryLogFormatText = "text"

	// QueryLogFormatJSON is the format specifier for json querylog output
	QueryLogFormatJSON = "json"
)

Variables

var (
	// RedactDebugUIQueries controls whether full queries and bind variables are suppressed from debug UIs.
	RedactDebugUIQueries = flag.Bool("redact-debug-ui-queries", false, "redact full queries and bind variables from debug UI")

	// QueryLogFormat controls the format of the query log (either text or json)
	QueryLogFormat = flag.String("querylog-format", "text", "format for query logs (\"text\" or \"json\")")

	// QueryLogFilterTag contains an optional string that must be present in the query for it to be logged
	QueryLogFilterTag = flag.String("querylog-filter-tag", "", "string that must be present in the query for it to be logged; if using a value as the tag, you need to disable query normalization")

	// QueryLogRowThreshold only log queries returning or affecting this many rows
	QueryLogRowThreshold = flag.Uint64("querylog-row-threshold", 0, "Number of rows a query has to return or affect before being logged; not useful for streaming queries. 0 means all queries will be logged.")
)

Functions

func ShouldEmitLog

func ShouldEmitLog(sql string, rowsAffected, rowsReturned uint64) bool

ShouldEmitLog returns whether the log with the given SQL query should be emitted or filtered

Types

type Formatter

type Formatter interface {
	Logf(io.Writer, url.Values) error
}

Formatter is a simple interface for objects that expose a Format function as needed for streamlog.

type LogFormatter

type LogFormatter func(out io.Writer, params url.Values, message interface{}) error

LogFormatter is the function signature used to format an arbitrary message for the given output writer.

func GetFormatter

func GetFormatter(logger *StreamLogger) LogFormatter

GetFormatter returns a formatter function for objects conforming to the Formatter interface

type StreamLogger

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

StreamLogger is a non-blocking broadcaster of messages. Subscribers can use channels or HTTP.

func New

func New(name string, size int) *StreamLogger

New returns a new StreamLogger that can stream events to subscribers. The size parameter defines the channel size for the subscribers.

func (*StreamLogger) LogToFile

func (logger *StreamLogger) LogToFile(path string, logf LogFormatter) (chan interface{}, error)

LogToFile starts logging to the specified file path and will reopen the file in response to SIGUSR2.

Returns the channel used for the subscription which can be used to close it.

func (*StreamLogger) Name

func (logger *StreamLogger) Name() string

Name returns the name of StreamLogger.

func (*StreamLogger) Send

func (logger *StreamLogger) Send(message interface{})

Send sends message to all the writers subscribed to logger. Calling Send does not block.

func (*StreamLogger) ServeLogs

func (logger *StreamLogger) ServeLogs(url string, logf LogFormatter)

ServeLogs registers the URL on which messages will be broadcast. It is safe to register multiple URLs for the same StreamLogger.

func (*StreamLogger) Subscribe

func (logger *StreamLogger) Subscribe(name string) chan interface{}

Subscribe returns a channel which can be used to listen for messages.

func (*StreamLogger) Unsubscribe

func (logger *StreamLogger) Unsubscribe(ch chan interface{})

Unsubscribe removes the channel from the subscription.