fix: cityHash64 result cast to string to avoid precision issues (#1496)

knudtty · web-flow · commit b99052ad8cf2 · 2025-12-17T19:09:46.000Z
Closes HDX-3073
diff --git a/.changeset/olive-nails-sleep.md b/.changeset/olive-nails-sleep.md
@@ -0,0 +1,5 @@
+---
+"@hyperdx/app": patch
+---
+
+fix: cityHash64 in sessions cast to string due to number precision issues in the browser
diff --git a/packages/app/src/SessionSubpanel.tsx b/packages/app/src/SessionSubpanel.tsx
@@ -280,7 +280,8 @@ export default function SessionSubpanel({
         alias: 'http.url',
       },
       {
-        valueExpression: `cityHash64(${traceSource.traceIdExpression}, ${traceSource.parentSpanIdExpression}, ${traceSource.spanIdExpression}, ${traceSource.timestampValueExpression})`,
+        // Using toString here because Javascript does not have the precision to accurately represent this
+        valueExpression: `toString(cityHash64(${traceSource.traceIdExpression}, ${traceSource.parentSpanIdExpression}, ${traceSource.spanIdExpression}))`,
         alias: 'id',
       },
       {

-Original file line number
+Diff line change
@@ @@ -0,0 +1,5 @@ @@
 +---
 +"@hyperdx/app": patch
 +---
++
 +fix: cityHash64 in sessions cast to string due to number precision issues in the browser
Original file line number	Diff line number	Diff line change
`@@ -280,7 +280,8 @@ export default function SessionSubpanel({`
`280`	`280`	`alias: 'http.url',`
`281`	`281`	`},`
`282`	`282`	`{`
`283`		- valueExpression: `cityHash64(${traceSource.traceIdExpression}, ${traceSource.parentSpanIdExpression}, ${traceSource.spanIdExpression}, ${traceSource.timestampValueExpression})`,
	`283`	`+ // Using toString here because Javascript does not have the precision to accurately represent this`
	`284`	+ valueExpression: `toString(cityHash64(${traceSource.traceIdExpression}, ${traceSource.parentSpanIdExpression}, ${traceSource.spanIdExpression}))`,
`284`	`285`	`alias: 'id',`
`285`	`286`	`},`
`286`	`287`	`{`