Sourcemaps Lookup Laravel Package

title: Tips for bulk lookups weight: 5

Dedupe maps by URL before the frame loop

When you resolve a full stack trace, multiple frames often share the same source map (for example, two frames in the same code-split chunk). Load each unique map once.

$mapsByUrl = [];
foreach ($frames as $frame) {
    $url = $frame['sourceMapUrl'];
    $mapsByUrl[$url] ??= SourceMapLookup::fromJson($fetch($url));
    $positions[] = $mapsByUrl[$url]->lookup($frame['line'], $frame['column']);
}

json_decode dominates the cost of a single cold lookup, so avoiding a redundant decode is the single biggest caller side win.

Multiple lookups against the same map are cheap

Once a line has been looked up, its parsed segments are cached on the SourceMapLookup instance. Subsequent lookups on the same (or later) lines reuse the work. This is the workload the package is tuned for.