import truncation from "rollbar/src/truncation";
// Type definition for the result returned by stringify function in rollbar/src/utility
interface StringifyResult {
error?: Error;
value: string;
}
// Type definition for the module rollbar/src/truncation
interface TruncationModule {
truncate: (
payload: any,
jsonBackup: typeof JSON.stringify,
maxSize: number,
) => StringifyResult;
}
const typedTruncation = truncation as TruncationModule;
const CHARS_PER_TOKEN = 4; // Rough estimate: 1 token = 4 characters
/**
* Truncates an occurrence to fit within token limit
* @param occurrence - The occurrence to truncate (like a 'payload' in rollbar.js; has a top-level 'data' key)
* @param maxTokens - Maximum allowed tokens (default: 25000)
* @returns Truncated data as a json object
*/
export function truncateOccurrence(
occurrence: any,
maxTokens: number = 25000,
): unknown {
// Convert token limit to approximate byte size for rollbar truncation
const maxBytes = maxTokens * CHARS_PER_TOKEN;
// Use rollbar.js truncation with our calculated max size
const result = typedTruncation.truncate(occurrence, JSON.stringify, maxBytes);
const truncatedPayload: unknown = JSON.parse(result.value);
return truncatedPayload;
}
