import { v5 as uuidv5 } from 'uuid'; import { MutableDataFrame } from '@grafana/data'; import { LokiStreamResult, LokiTailResponse } from './types'; const UUID_NAMESPACE = '6ec946da-0f49-47a8-983a-1d76d17e7c92'; /** * Transform LokiResponse data and appends it to MutableDataFrame. Used for streaming where the dataFrame can be * a CircularDataFrame creating a fixed size rolling buffer. * TODO: Probably could be unified with the logStreamToDataFrame function. * @param response * @param data Needs to have ts, line, labels, id as fields */ export function appendResponseToBufferedData(response: LokiTailResponse, data: MutableDataFrame) { // Should we do anything with: response.dropped_entries? const streams: LokiStreamResult[] = response.streams; if (!streams || !streams.length) { return; } const tsField = data.fields[0]; const lineField = data.fields[1]; const idField = data.fields[2]; // We are comparing used ids only within the received stream. This could be a problem if the same line + labels + nanosecond timestamp came in 2 separate batches. // As this is very unlikely, and the result would only affect live-tailing css animation we have decided to not compare all received uids from data param as this would slow down processing. const usedUids: Record<string, number> = {}; for (const stream of streams) { // Find unique labels const allLabelsString = Object.entries(stream.stream) .map(([key, val]) => `${key}="${val}"`) .sort() .join(''); // Add each line for (const [ts, line] of stream.values) { tsField.values.push(new Date(parseInt(ts.slice(0, -6), 10)).toISOString()); lineField.values.push(line); idField.values.push(createUid(ts, allLabelsString, line, usedUids, data.refId)); } } } function createUid( ts: string, labelsString: string, line: string, usedUids: Record<string, number>, refId?: string ): string { // Generate id as hashed nanosecond timestamp, labels and line (this does not have to be unique) let id = uuidv5(`${ts}_${labelsString}_${line}`, UUID_NAMESPACE); // Check if generated id is unique // If not and we've already used it, append its count after it if (id in usedUids) { // Increase the count const newCount = usedUids[id] + 1; usedUids[id] = newCount; // Append count to generated id to make it unique id = `${id}_${newCount}`; } else { // If id is unique and wasn't used, add it to usedUids and start count at 0 usedUids[id] = 0; } // Return unique id if (refId) { return `${refId}_${id}`; } return id; }