feat: Pick up sentry-trace in JS <meta/> tag #2703
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HazAT
changed the title
| let parentSpanId; | ||
| let sampled; | ||
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| const header = Tracing._getMeta('sentry-trace'); |
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So I guess now if someone sets this in an SPA, all transactions would use this meta header right?
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Correct. For me this is opt-in behavior enough, this can't happen by accident so guarding this behind an option in the integration doesn't make a lot of sense to me.
| @@ -42,13 +43,15 @@ export function tracingHandler(): ( | |||
| if (span) { | |||
| traceId = span.traceId; | |||
| parentSpanId = span.parentSpanId; | |||
| sampled = span.sampled; | |||
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This is a bug fix right? We should remember for the changelog then that there are two changes in this PR. a feat for the meta tag, and a fix for sampling from trace parent in node.
| private static _getMeta(metaName: string): string | null { | ||
| const metas = document.getElementsByTagName('meta'); | ||
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| // tslint:disable-next-line: prefer-for-of | ||
| for (let i = 0; i < metas.length; i++) { | ||
| if (metas[i].getAttribute('name') === metaName) { | ||
| return metas[i].getAttribute('content'); | ||
| } | ||
| } | ||
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| return null; | ||
| } |
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| private static _getMeta(metaName: string): string | null { | |
| const metas = document.getElementsByTagName('meta'); | |
| // tslint:disable-next-line: prefer-for-of | |
| for (let i = 0; i < metas.length; i++) { | |
| if (metas[i].getAttribute('name') === metaName) { | |
| return metas[i].getAttribute('content'); | |
| } | |
| } | |
| return null; | |
| } | |
| private static _getMeta(metaName: string): string | undefined { | |
| return (document.querySelector(`meta[name=${metaName}]`) || {}).content; | |
| } |
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This has typescript errors, I will go with
const el = document.querySelector(`meta[name=${metaName}]`);
return el ? el.getAttribute('content') : null;
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Ah, silly empty object typing 🎳
| parentSpanId = span.parentSpanId; | ||
| sampled = span.sampled; | ||
| } | ||
| Tracing._log( |
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This log will be incorrect if span is falsy. Should be moved inside span or corrected logically.
Add functionality to
Tracingintegration to pick up<meta name="sentry-trace" />to continue a trace in the frontend.The reason why it's a
<meta/>tag is that a<script/>tag setting something on the window would block rendering.Right now, only Laravel can provide this meta tag with this PR
getsentry/sentry-laravel#358
This is for cases where the Trace is not started from the frontend but from the backend.
It can be also useful for other webframeworks that are not SPA and instead still render templates from backend -> frontend.