Distributed Tracing Doesn't Seem to Work With Built Files

[wrumsby]

Description

I've tried using the built files to host the SPA agent locally with a configuration like the following:

<script type="text/javascript">
  window.NREUM||(NREUM={});
  NREUM.init = {
    distributed_tracing: {
      enabled: true,
      cors_use_newrelic_header: true,
      cors_use_tracecontext_headers: true,
      allowed_origins: [/* array of strings of origins, e.g. 'https://example.com', 'https://mydomain' */]
    },
    privacy: {
      cookies_enabled: true
    }
  };
  NREUM.info = {
    licenseKey: "/* my license key */",
    applicationID: /* my application id */,
    agent: "https://MY_CDN/nr-spa.js"
  };
</script>
<script src="https://MY_CDN/nr-loader-spa.js"></script>

It appears that most of the standard browser monitoring works, but distributed tracing does not.

Steps to Reproduce

1. clone this project
2. run npm run build
3. upload the generated nr-spa.js and nr-spa-loader.js to a CDN, web server, etc.
4. initialise the agent to use distributed tracing with a set of allowed domains that are also configured to support distributed tracing headers
5. in a browser app using the generated scripts make XHR requests which should be included in distributed traces

Expected Behavior

• AJAX requests are made with tracestate, traceparent and newrelic headers
• requests appear in Distributed Tracing

Relevant Logs / Console output

Your Environment

• Chome 91.0.4472.101
• OS X 11.4

Additional context

[aubreymasten]

Hey @wrumsby, thanks for all the detail here! You may need to include some additional attributes in NREUM.info for distributed tracing to work. If you add accountId and agentId to that config block, are the headers still not showing up on outgoing requests?

The agent checks these attributes before generating Distributed Tracing headers here:

newrelic-browser-agent/feature/xhr/instrument/distributed-tracing.js

Lines 28 to 30 in ef2a15c

	if (!accountId || !agentId) {
	return null
	}

You may also want to add the trustKey attribute and give it the same value as accountId if traces aren't showing up in the UI.

Let me know if that works or you run into other issues!

[wrumsby]

Hello @aubreymasten, yes it does seem I need to include the following to get distributed tracing to work:

NREUM.loader_config = {
  accountID: /* my account id */,
  trustKey: /* my account id */,
  agentID: /* my application id */
};

I'll close this issue as this now works for me, but it might be worth including more details about init, info and loader_config in the agent documentation.