dd-trace-go.v1: gopkg.in/DataDog/dd-trace-go.v1/contrib/gocql/gocql Index | Examples | Files

package gocql

import "gopkg.in/DataDog/dd-trace-go.v1/contrib/gocql/gocql"

Package gocql provides functions to trace the gocql/gocql package (https://github.com/gocql/gocql).

To trace Cassandra commands, use our query wrapper WrapQuery.

Code:

// Initialise a Cassandra session as usual, create a query.
cluster := gocql.NewCluster("127.0.0.1")
session, _ := cluster.CreateSession()
query := session.Query("CREATE KEYSPACE if not exists trace WITH REPLICATION = { 'class' : 'SimpleStrategy', 'replication_factor': 1}")

// Use context to pass information down the call chain
_, ctx := tracer.StartSpanFromContext(context.Background(), "parent.request",
    tracer.SpanType(ext.SpanTypeCassandra),
    tracer.ServiceName("web"),
    tracer.ResourceName("/home"),
)

// Wrap the query to trace it and pass the context for inheritance
tracedQuery := gocqltrace.WrapQuery(query, gocqltrace.WithServiceName("ServiceName"))
tracedQuery.WithContext(ctx)

// Execute your query as usual
tracedQuery.Exec()

Index

Examples

Package Files

gocql.go option.go

type Iter Uses

type Iter struct {
    *gocql.Iter
    // contains filtered or unexported fields
}

Iter inherits from gocql.Iter and contains a span.

func (*Iter) Close Uses

func (tIter *Iter) Close() error

Close closes the Iter and finish the span created on Iter call.

type Query Uses

type Query struct {
    *gocql.Query
    // contains filtered or unexported fields
}

Query inherits from gocql.Query, it keeps the tracer and the context.

func WrapQuery Uses

func WrapQuery(q *gocql.Query, opts ...WrapOption) *Query

WrapQuery wraps a gocql.Query into a traced Query under the given service name. Note that the returned Query structure embeds the original gocql.Query structure. This means that any method returning the query for chaining that is not part of this package's Query structure should be called before WrapQuery, otherwise the tracing context could be lost.

To be more specific: it is ok (and recommended) to use and chain the return value of `WithContext` and `PageState` but not that of `Consistency`, `Trace`, `Observer`, etc.

func (*Query) Exec Uses

func (tq *Query) Exec() error

Exec is rewritten so that it passes by our custom Iter

func (*Query) Iter Uses

func (tq *Query) Iter() *Iter

Iter starts a new span at query.Iter call.

func (*Query) MapScan Uses

func (tq *Query) MapScan(m map[string]interface{}) error

MapScan wraps in a span query.MapScan call.

func (*Query) PageState Uses

func (tq *Query) PageState(state []byte) *Query

PageState rewrites the original function so that spans are aware of the change.

func (*Query) Scan Uses

func (tq *Query) Scan(dest ...interface{}) error

Scan wraps in a span query.Scan call.

func (*Query) ScanCAS Uses

func (tq *Query) ScanCAS(dest ...interface{}) (applied bool, err error)

ScanCAS wraps in a span query.ScanCAS call.

func (*Query) WithContext Uses

func (tq *Query) WithContext(ctx context.Context) *Query

WithContext adds the specified context to the traced Query structure.

type WrapOption Uses

type WrapOption func(*queryConfig)

WrapOption represents an option that can be passed to WrapQuery.

func NoDebugStack Uses

func NoDebugStack() WrapOption

NoDebugStack prevents stack traces from being attached to spans finishing with an error. This is useful in situations where errors are frequent and performance is critical.

func WithAnalytics Uses

func WithAnalytics(on bool) WrapOption

WithAnalytics enables Trace Analytics for all started spans.

func WithAnalyticsRate Uses

func WithAnalyticsRate(rate float64) WrapOption

WithAnalyticsRate sets the sampling rate for Trace Analytics events correlated to started spans.

func WithResourceName Uses

func WithResourceName(name string) WrapOption

WithResourceName sets a custom resource name to be used with the traced query. By default, the query statement is extracted automatically. This method should be used when a different resource name is desired or in performance critical environments. The gocql library returns the query statement using an fmt.Sprintf call, which can be costly when called repeatedly. Using WithResourceName will avoid that call. Under normal circumstances, it is safe to rely on the default.

func WithServiceName Uses

func WithServiceName(name string) WrapOption

WithServiceName sets the given service name for the returned query.

Package gocql imports 10 packages (graph) and is imported by 2 packages. Updated 2020-08-05. Refresh now. Tools for package owners.