tracing

Documentation

Index

• Constants
• func GetCorrelationID(ctx context.Context) string
• func HTTPMiddleware(next http.Handler) http.Handler
• func SQLMiddleware(ctx context.Context, queryName, query string, args ...interface{}) (context.Context, sql.MiddlewareEnd, error)
• func TraceOutbound(r *http.Request, span opentracing.Span) error
• type Config
  • func (c Config) ConfigureTracer() io.Closer
  • func (c *Config) RegisterFlags(flags *pflag.FlagSet)

Constants

const CorrelationIDCtxKey = "CorrelationIDCtxKey"

CorrelationIDCtxKey is the key into the Context of the wrapped HTTP request which maps to the correlation id of the request. This correlation ID can be conveyed to external clients in order to correlate external systems with SpotHero tracing and logging.

Functions

func GetCorrelationID

func GetCorrelationID(ctx context.Context) string

GetCorrelationID returns the correlation ID associated with the given Context. This function only produces meaningful results for Contexts associated with http.Requests which have passed through tracing/HTTPMiddleware.

func HTTPMiddleware

func HTTPMiddleware(next http.Handler) http.Handler

HTTPMiddleware extracts the OpenTracing context on all incoming HTTP requests, if present. if no trace ID is present in the headers, a trace is initiated.

The following tags are placed on all incoming HTTP requests: * http.method * http.url

Outbound responses will be tagged with the following tags, if applicable: * http.status_code * error (if the status code is >= 500)

The returned HTTP Request includes the wrapped OpenTracing Span Context. Note that this middleware must be attached after writer.StatusRecorderMiddleware for HTTP response span tagging to function.

func SQLMiddleware

func SQLMiddleware(ctx context.Context, queryName, query string, args ...interface{}) (context.Context, sql.MiddlewareEnd, error)

SQLMiddleware traces requests made against SQL databases.

Span names always start with "db". If a queryName is provided (highly recommended), the span name will include the queryname in the format "db_<queryName>"

The following tags are placed on all SQL traces: * component - Always set to "tracing" * db.type - Always set to "sql" * db.statement - Always set to the query statement * error - Set to true only if an error was encountered with the query

func TraceOutbound

func TraceOutbound(r *http.Request, span opentracing.Span) error

TraceOutbound injects outbound HTTP requests with OpenTracing headers

Types

type Config

type Config struct {
	Enabled               bool
	SamplerType           string
	SamplerParam          float64
	ReporterLogSpans      bool
	ReporterMaxQueueSize  int
	ReporterFlushInterval time.Duration
	AgentHost             string
	AgentPort             int
	ServiceName           string
}

Config defines the necessary configuration for instantiating a Tracer

func (Config) ConfigureTracer

func (c Config) ConfigureTracer() io.Closer

ConfigureTracer instantiates and configures the OpenTracer and returns the tracer closer

func (*Config) RegisterFlags

func (c *Config) RegisterFlags(flags *pflag.FlagSet)

RegisterFlags registers Tracer flags with pflags