erroropennode-demojavascript

TypeError: Cannot read properties of undefined (reading 'id')

demo.js#resolveUser

Events3
First seen14d ago2026-08-09 15:27:09 UTC
Last seen14d ago2026-08-09 16:11:52 UTC
Releasesnode-demo-1.0.0 → node-demo-coldstart

Frequency

24 hours7 days30 days
Events per day, from the rollups0 in this window · peak 1
17 Aug
 
19 Aug
 
21 Aug
 
23 Aug
Table view
Bucket (UTC)Events
2026-08-17 00:00:000
2026-08-18 00:00:000
2026-08-19 00:00:000
2026-08-20 00:00:000
2026-08-21 00:00:000
2026-08-22 00:00:000
2026-08-23 00:00:000

How this group was decided

Every step below is a pure function of the event. The same event always produces the same group.

  1. 1 · Parse the stack trace

    10 frames parsed, 4 belong to the application. Only those decide the group — the same bug reaches the runtime through different framework paths depending on the request.

    • in-appdemo.js.resolveUserdemo.js:26
    • in-appdemo.js.handlerdemo.js:31
    • in-appdemo.js.maindemo.js:42
    • in-appObject.<anonymous>demo.js:79
    • vendorModule._compilenode:internal/modules/cjs/loader:1761
    • vendorObject..jsnode:internal/modules/cjs/loader:1893
    • vendorModule.loadnode:internal/modules/cjs/loader:1481
    • vendorModule._loadnode:internal/modules/cjs/loader:1300
    • vendorTracingChannel.traceSyncnode:diagnostics_channel:328
    • vendornode:internal/modules/cjs/loader.wrapModuleLoadnode:internal/modules/cjs/loader:245

  2. 2 · Build the fingerprint input

    Line numbers are dropped so that editing a line above the throw site does not open a new group. Values inside the message are replaced with placeholders.

    v1
platform=javascript
service=node-demo
type=TypeError
frame=demo.js#resolveUser
frame=demo.js#handler
frame=demo.js#main
frame=Object#<anonymous>

  3. 3 · Hash it

    SHA-256 of the text above, truncated to 128 bits. The version is part of the group key: a future algorithm opens new groups rather than rewriting these.

    Fingerprint
    e9930574487b570d9e7633bf75ba64b4
    Algorithm version
    v1

Latest stored event

2026-08-09 16:11:52 UTC

Cannot read properties of undefined (reading 'id')

TypeError: Cannot read properties of undefined (reading 'id')
    at resolveUser (D:\Stacklight\examples\node-demo\demo.js:26:25)
    at handler (D:\Stacklight\examples\node-demo\demo.js:31:12)
    at main (D:\Stacklight\examples\node-demo\demo.js:42:5)
    at Object.<anonymous> (D:\Stacklight\examples\node-demo\demo.js:79:1)
    at Module._compile (node:internal/modules/cjs/loader:1761:14)
    at Object..js (node:internal/modules/cjs/loader:1893:10)
    at Module.load (node:internal/modules/cjs/loader:1481:32)
    at Module._load (node:internal/modules/cjs/loader:1300:12)
    at TracingChannel.traceSync (node:diagnostics_channel:328:14)
    at wrapModuleLoad (node:internal/modules/cjs/loader:245:24)

Similar groups

Trigram similarity computed by Postgres against a GIN index. It catches what a fingerprint cannot — the same fault one refactor away from an existing group. No model is involved.