35 lines
840 B
Go
35 lines
840 B
Go
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package tracer
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import (
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"io/ioutil"
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"log"
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"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/ext"
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)
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// A basic example demonstrating how to start the tracer, as well as how
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// to create a root span and a child span that is a descendant of it.
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func Example() {
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// Start the tracer and defer the Stop method.
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Start(WithAgentAddr("host:port"))
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defer Stop()
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// Start a root span.
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span := StartSpan("get.data")
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defer span.Finish()
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// Create a child of it, computing the time needed to read a file.
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child := StartSpan("read.file", ChildOf(span.Context()))
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child.SetTag(ext.ResourceName, "test.json")
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// Perform an operation.
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_, err := ioutil.ReadFile("~/test.json")
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// We may finish the child span using the returned error. If it's
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// nil, it will be disregarded.
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child.Finish(WithError(err))
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if err != nil {
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log.Fatal(err)
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}
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}
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