feat(core): Support array attributes for spans, logs and metrics by nicohrubec · Pull Request #20427 · getsentry/sentry-javascript

nicohrubec · 2026-04-21T16:48:02Z

Adds array attribute support for spans, logs, and metrics. Relay only supports primitive homogeneous arrays (all elements have the same primitive type). However, any attributes with non-conforming arrays will be dropped by Relay, so there is no need for runtime validation on the SDK end.

This change as is comes with a behavioral change for user-defined logs and metrics. If users previously set array attributes for logs/metrics then these were previously sent to Sentry stringified, now these will be sent as arrays. After discussion with product teams we also decided not to drop empty arrays.

Note: the Sentry frontend doesn't render array attributes correctly yet, but that's expected to land soon.

Blocks #20428
Closes #20651
Closes #20438

Relay's wire contract (AttributeType enum in relay-event-schema) defines exactly five `type:` tags: boolean, integer, double, string, array. The SDK's AttributeTypeMap previously declared typed array variants (`string[]`, `integer[]`, etc.) that Relay does not recognize - these were never actually emitted because the runtime serializer only handled primitives, so array-valued attributes silently dropped. This change: - Collapses the four `x[]` variants in AttributeTypeMap into a single `array` variant whose value is `Array<string> | Array<number> | Array<boolean>`. - Extends getTypedAttributeValue to auto-detect homogeneous primitive arrays and emit `{type: 'array', value: [...]}`. - Adds an isHomogeneousPrimitiveArray guard so mixed-type and nested arrays remain unsupported (dropped by default, stringified under the fallback path). - Updates tests to cover the new typed-array path (including empty arrays, unit preservation, and mixed-type drop/stringify). Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

github-actions · 2026-04-21T16:58:09Z

size-limit report 📦

Path	Size	% Change	Change
@sentry/browser	26.3 kB	-	-
@sentry/browser - with treeshaking flags	24.78 kB	-	-
@sentry/browser (incl. Tracing)	44.17 kB	+0.01%	+1 B 🔺
@sentry/browser (incl. Tracing + Span Streaming)	46.4 kB	+0.03%	+13 B 🔺
@sentry/browser (incl. Tracing, Profiling)	49.14 kB	-	-
@sentry/browser (incl. Tracing, Replay)	83.63 kB	-	-
@sentry/browser (incl. Tracing, Replay) - with treeshaking flags	73.08 kB	-	-
@sentry/browser (incl. Tracing, Replay with Canvas)	88.33 kB	+0.01%	+1 B 🔺
@sentry/browser (incl. Tracing, Replay, Feedback)	100.93 kB	-	-
@sentry/browser (incl. Feedback)	43.44 kB	-	-
@sentry/browser (incl. sendFeedback)	31.11 kB	+0.01%	+1 B 🔺
@sentry/browser (incl. FeedbackAsync)	36.19 kB	-	-
@sentry/browser (incl. Metrics)	27.61 kB	+0.05%	+13 B 🔺
@sentry/browser (incl. Logs)	27.75 kB	+0.08%	+20 B 🔺
@sentry/browser (incl. Metrics & Logs)	28.44 kB	+0.05%	+13 B 🔺
@sentry/react	28.04 kB	-	-
@sentry/react (incl. Tracing)	46.4 kB	-0.01%	-1 B 🔽
@sentry/vue	31.18 kB	+0.01%	+1 B 🔺
@sentry/vue (incl. Tracing)	46.02 kB	-	-
@sentry/svelte	26.32 kB	-	-
CDN Bundle	28.92 kB	+0.05%	+13 B 🔺
CDN Bundle (incl. Tracing)	46.95 kB	+0.03%	+10 B 🔺
CDN Bundle (incl. Logs, Metrics)	30.35 kB	+0.05%	+13 B 🔺
CDN Bundle (incl. Tracing, Logs, Metrics)	48.05 kB	+0.03%	+13 B 🔺
CDN Bundle (incl. Replay, Logs, Metrics)	69.48 kB	+0.02%	+12 B 🔺
CDN Bundle (incl. Tracing, Replay)	84.14 kB	+0.02%	+10 B 🔺
CDN Bundle (incl. Tracing, Replay, Logs, Metrics)	85.21 kB	+0.02%	+11 B 🔺
CDN Bundle (incl. Tracing, Replay, Feedback)	89.96 kB	+0.02%	+11 B 🔺
CDN Bundle (incl. Tracing, Replay, Feedback, Logs, Metrics)	91.03 kB	+0.01%	+8 B 🔺
CDN Bundle - uncompressed	84.94 kB	+0.07%	+54 B 🔺
CDN Bundle (incl. Tracing) - uncompressed	140.49 kB	+0.04%	+54 B 🔺
CDN Bundle (incl. Logs, Metrics) - uncompressed	89.13 kB	+0.07%	+54 B 🔺
CDN Bundle (incl. Tracing, Logs, Metrics) - uncompressed	143.96 kB	+0.04%	+54 B 🔺
CDN Bundle (incl. Replay, Logs, Metrics) - uncompressed	213.35 kB	+0.03%	+54 B 🔺
CDN Bundle (incl. Tracing, Replay) - uncompressed	258.6 kB	+0.03%	+54 B 🔺
CDN Bundle (incl. Tracing, Replay, Logs, Metrics) - uncompressed	262.05 kB	+0.03%	+54 B 🔺
CDN Bundle (incl. Tracing, Replay, Feedback) - uncompressed	272.3 kB	+0.02%	+54 B 🔺
CDN Bundle (incl. Tracing, Replay, Feedback, Logs, Metrics) - uncompressed	275.73 kB	+0.02%	+54 B 🔺
@sentry/nextjs (client)	48.9 kB	-	-
@sentry/sveltekit (client)	44.64 kB	-	-
@sentry/node-core	60.49 kB	+0.04%	+23 B 🔺
@sentry/node	165.53 kB	+0.02%	+30 B 🔺
@sentry/node - without tracing	73.52 kB	+0.04%	+28 B 🔺
@sentry/aws-serverless	107.65 kB	+0.02%	+20 B 🔺
@sentry/cloudflare (withSentry) - minified	169.4 kB	+0.03%	+49 B 🔺
@sentry/cloudflare (withSentry)	427.57 kB	+0.02%	+71 B 🔺

View base workflow run

Arrays that were previously dropped by the serializer now ship as native array attributes (`type: 'array'`). Update the affected integration test expectations and bump size-limit thresholds for the five bundle scenarios whose gzipped/uncompressed sizes grew from the new serializer logic. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Drop the size-limit increases for the five bundle scenarios that grew from adding homogeneous primitive array support. Test expectation updates from the previous commit stay. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Re-apply the size-limit bumps needed to account for the new homogeneous-primitive-array detection logic. Five scenarios grew past their thresholds: - @sentry/browser (incl. Metrics & Logs): 28 → 29 KB - CDN Bundle (incl. Logs, Metrics): 30 → 31 KB - CDN Bundle (incl. Tracing, Replay, Logs, Metrics) - uncompressed: 258.5 → 259 KB - CDN Bundle (incl. Tracing, Replay, Feedback) - uncompressed: 268 → 269 KB - CDN Bundle (incl. Tracing, Replay, Feedback, Logs, Metrics) - uncompressed: 271.5 → 272 KB Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

…72 KB Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

andreiborza · 2026-04-29T05:37:20Z

  }
 }
+
+function isHomogeneousPrimitiveArray(arr: unknown): arr is Array<string> | Array<number> | Array<boolean> {


q: Was it previously decided that SDKs have to guarantee homogeneity? Just wondering if we really have to iterate over the entire array for every array.

Jap fair question, we are still discussing that one 😅

Talked to ingest: We don't need any SDK-side runtime validation.

nicohrubec · 2026-04-29T07:46:25Z

Converting back to draft until we have a definitive answer for SDK validation.

nicohrubec · 2026-05-04T12:48:23Z

@chargome @mydea I talked to Ingest last week and the outcome was that we don't need any SDK-side runtime validation for user-set arrays on attributes. Relay will just drop any attributes with non-conforming arrays set as values. Based on that I simplified the PR, should be good for another look. The frontend still doesn't display these properly yet though. I will make sure to properly test this e2e before merging after the FE is ready.

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cursor · 2026-05-04T14:10:13Z

 */
 function getTypedAttributeValue(value: unknown): TypedAttributeValue | void {
+  if (Array.isArray(value) && value.length !== 0) {
+    return { value, type: 'array' };


Mixed-type array console parameters silently dropped by Relay

Medium Severity

The getTypedAttributeValue function now converts all non-empty arrays to { type: 'array' } before the stringify fallback path is reached. This means SDK-internal sentry.message.parameter.X attributes created by createConsoleTemplateAttributes from mixed-type console args (e.g. console.log('Array:', [1, 2, 3, 'string'])) are now sent as array attributes instead of being stringified. Since Relay drops non-homogeneous arrays, these template parameters will be silently lost — a regression from the previous behavior where they were preserved as stringified values. The body text is unaffected, but structured template parameter data is lost for mixed-type arrays.

^{Reviewed by Cursor Bugbot for commit f896f3a. Configure here.}

this is basically what I described in the PR description, we can discuss it but I think this is a tradeoff we have to make. don't think we can really solve this unless we do runtime inspection of the types of elements in arrays

chargome · 2026-05-04T14:34:39Z

 export type Attributes = Record<string, TypedAttributeValue>;

-export type AttributeValueType = string | number | boolean | Array<string> | Array<number> | Array<boolean>;
+export type AttributeValueType = string | number | boolean | Array<unknown>;


h: Do we really want Array<unknown>? Every change that follows would be breaking from here on.

Narrowed it down again

chargome

chargome · 2026-05-04T15:45:57Z

      value: expect.any(Number),
    },
-    // TODO: 'device.archs' is set but arrays are not yet serialized in span attributes
+    'device.archs': {


Thanks for pulling this one in.

JPeer264 · 2026-05-05T08:50:11Z

-  'integer[]': Array<number>;
-  'double[]': Array<number>;
-  'boolean[]': Array<boolean>;
+  array: Array<string> | Array<number> | Array<boolean>;


q: Would be BigInt supported as well? I think this is a broader question actually

Mhm not sure. I assume relay enforces some number maximum but no idea what that is.

logaretm

@nicohrubec Do u think it is worth warning in debug if we detect non-homogenous attributes in the array?

Just to ease detecting this for the end user.

logaretm · 2026-05-05T19:42:20Z

- *    https://github.com/getsentry/sentry-javascript/pull/18165
 */
 function getTypedAttributeValue(value: unknown): TypedAttributeValue | void {
+  if (Array.isArray(value) && value.length !== 0) {


@nicohrubec q: what happens in empty arrays? are they still stringified?

as discussed I'll switch that logic to early return for empty arrays so they get dropped for both fallback/non-fallback paths. the way it is right now if fallback is enabled we send a stringified empty array if the fallback is on

actually after further discussion we won't be dropping empty arrays (independent of fallback on/off)

Now that array attributes are serialized, `device.archs` is no longer dropped — uncomment and enable the assertions in integration tests. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

nicohrubec and others added 8 commits April 21, 2026 19:28

Revert ".size-limit.js" bumps

fa70b75

Drop the size-limit increases for the five bundle scenarios that grew from adding homogeneous primitive array support. Test expectation updates from the previous commit stay. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Merge branch 'develop' into nh/array-attribute-support

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types

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Merge branch 'develop' into nh/array-attribute-support

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formatting

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Merge branch 'develop' into nh/array-attribute-support

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nicohrubec marked this pull request as ready for review April 28, 2026 11:16

nicohrubec marked this pull request as draft April 28, 2026 11:16

nicohrubec changed the title ~~feat(core): Support homogeneous primitive arrays as span attributes~~ feat(core): Support homogeneous primitive arrays as span/metric/log attributes Apr 28, 2026

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guard against nan

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nicohrubec marked this pull request as ready for review April 28, 2026 11:37

nicohrubec mentioned this pull request Apr 28, 2026

feat(core): Emit sentry.sdk.integrations on segment spans in span streaming #20428

Draft

chore(size-limit): Bump CDN Tracing+Replay+Feedback uncompressed to 2…

735bbe8

…72 KB Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

nicohrubec requested review from andreiborza, chargome and mydea April 28, 2026 12:04

andreiborza approved these changes Apr 29, 2026

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nicohrubec marked this pull request as draft April 29, 2026 07:46

Merge branch 'develop' into nh/array-attribute-support

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Comment thread packages/core/src/attributes.ts Outdated

Comment thread packages/core/src/attributes.ts Outdated

nicohrubec and others added 4 commits May 4, 2026 13:57

no runtime validation

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Merge branch 'develop' into nh/array-attribute-support

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add changelog

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update changelog

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nicohrubec added 2 commits May 4, 2026 14:38

.

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nicohrubec requested a review from chargome May 4, 2026 12:48

nicohrubec marked this pull request as ready for review May 4, 2026 12:48

nicohrubec requested review from a team as code owners May 4, 2026 12:48

nicohrubec changed the title ~~feat(core): Support homogeneous primitive arrays as span/metric/log attributes~~ feat(core): Support array attributes for spans, logs and metrics May 4, 2026

nicohrubec and others added 3 commits May 4, 2026 15:42

fix test

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Merge branch 'develop' into nh/array-attribute-support

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fix test

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nicohrubec added 3 commits May 4, 2026 17:32

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nicohrubec and others added 3 commits May 7, 2026 10:51

emit empty arrays

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Merge branch 'develop' into nh/array-attribute-support

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fix(tests): Expect device.archs array attribute in streamed span tests

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Now that array attributes are serialized, `device.archs` is no longer dropped — uncomment and enable the assertions in integration tests. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

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size-limit report 📦

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Mixed-type array console parameters silently dropped by Relay

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