2025-04-01 10:38:02 +09:00

521 lines
20 KiB
TypeScript

import { flatten } from 'lodash';
import { LRUCache } from 'lru-cache';
import { AbstractQuery, getDefaultTimeRange, KeyValue, LanguageProvider, ScopedVars, TimeRange } from '@grafana/data';
import { BackendSrvRequest, config } from '@grafana/runtime';
import { DEFAULT_MAX_LINES_SAMPLE, LokiDatasource } from './datasource';
import { abstractQueryToExpr, mapAbstractOperatorsToOp, processLabels } from './languageUtils';
import { getStreamSelectorsFromQuery } from './queryUtils';
import { buildVisualQueryFromString } from './querybuilder/parsing';
import {
extractLabelKeysFromDataFrame,
extractLogParserFromDataFrame,
extractUnwrapLabelKeysFromDataFrame,
} from './responseUtils';
import { DetectedFieldsResult, LabelType, LokiQuery, LokiQueryType, ParserAndLabelKeysResult } from './types';
const NS_IN_MS = 1000000;
const EMPTY_SELECTOR = '{}';
const HIDDEN_LABELS = ['__aggregrated_metric__', '__tenant_id__', '__stream_shard__'];
export default class LokiLanguageProvider extends LanguageProvider {
labelKeys: string[];
started = false;
startedTimeRange?: TimeRange;
datasource: LokiDatasource;
/**
* Cache for labels of series. This is bit simplistic in the sense that it just counts responses each as a 1 and does
* not account for different size of a response. If that is needed a `length` function can be added in the options.
* 10 as a max size is totally arbitrary right now.
*/
private seriesCache = new LRUCache<string, Record<string, string[]>>({ max: 10 });
private labelsCache = new LRUCache<string, string[]>({ max: 10 });
private detectedFieldValuesCache = new LRUCache<string, string[]>({ max: 10 });
private labelsPromisesCache = new LRUCache<string, Promise<string[]>>({ max: 10 });
private detectedLabelValuesPromisesCache = new LRUCache<string, Promise<string[]>>({ max: 10 });
constructor(datasource: LokiDatasource, initialValues?: any) {
super();
this.datasource = datasource;
this.labelKeys = [];
Object.assign(this, initialValues);
}
request = async (
url: string,
params?: Record<string, string | number>,
throwError?: boolean,
requestOptions?: Partial<BackendSrvRequest>
) => {
try {
return await this.datasource.metadataRequest(url, params, requestOptions);
} catch (error) {
if (throwError) {
throw error;
} else {
console.error(error);
}
}
return undefined;
};
/**
* Initialize the language provider by fetching set of labels.
*/
start = (timeRange?: TimeRange) => {
const range = timeRange ?? this.getDefaultTimeRange();
const newRangeParams = this.datasource.getTimeRangeParams(range);
const prevRangeParams = this.startedTimeRange ? this.datasource.getTimeRangeParams(this.startedTimeRange) : null;
// refetch labels if either there's not already a start task or the time range has changed
if (
!this.startTask ||
!prevRangeParams ||
newRangeParams.start !== prevRangeParams.start ||
newRangeParams.end !== prevRangeParams.end
) {
this.startedTimeRange = range;
this.startTask = this.fetchLabels({ timeRange: range }).then(() => {
this.started = true;
return [];
});
}
return this.startTask;
};
/**
* Returns the label keys that have been fetched.
* If labels have not been fetched yet, it will return an empty array.
* For updated labels (which should not happen often), use fetchLabels.
* @todo It is quite complicated to know when to use fetchLabels and when to use getLabelKeys.
* We should consider simplifying this and use caching in the same way as with seriesCache and labelsCache
* and just always use fetchLabels.
* Caching should be thought out properly, so we are not fetching this often, as labelKeys should not be changing often.
*
* @returns {string[]} An array of label keys or an empty array if labels have not been fetched.
*/
getLabelKeys(): string[] {
return this.labelKeys;
}
importFromAbstractQuery(labelBasedQuery: AbstractQuery): LokiQuery {
return {
refId: labelBasedQuery.refId,
expr: abstractQueryToExpr(labelBasedQuery),
queryType: LokiQueryType.Range,
};
}
exportToAbstractQuery(query: LokiQuery): AbstractQuery {
if (!query.expr || query.expr.length === 0) {
return { refId: query.refId, labelMatchers: [] };
}
const streamSelectors = getStreamSelectorsFromQuery(query.expr);
const labelMatchers = streamSelectors.map((streamSelector) => {
const visualQuery = buildVisualQueryFromString(streamSelector).query;
const matchers = visualQuery.labels.map((label) => {
return {
name: label.label,
value: label.value,
operator: mapAbstractOperatorsToOp[label.op],
};
});
return matchers;
});
return {
refId: query.refId,
labelMatchers: flatten(labelMatchers),
};
}
/**
* Fetch label keys using the best applicable endpoint.
*
* This asynchronous function returns all available label keys from the data source.
* It returns a promise that resolves to an array of strings containing the label keys.
*
* @param options - (Optional) An object containing additional options.
* @param options.streamSelector - (Optional) The stream selector to filter label keys. If not provided, all label keys are fetched.
* @param options.timeRange - (Optional) The time range for which you want to retrieve label keys. If not provided, the default time range is used.
* @returns A promise containing an array of label keys.
* @throws An error if the fetch operation fails.
*/
async fetchLabels(options?: { streamSelector?: string; timeRange?: TimeRange }): Promise<string[]> {
// We'll default to use `/labels`. If the flag is disabled, and there's a streamSelector, we'll use the series endpoint.
if (config.featureToggles.lokiLabelNamesQueryApi || !options?.streamSelector) {
return this.fetchLabelsByLabelsEndpoint(options);
} else {
const data = await this.fetchSeriesLabels(options.streamSelector, { timeRange: options.timeRange });
return Object.keys(data ?? {});
}
}
/**
* Fetch all label keys
* This asynchronous function returns all available label keys from the data source.
* It returns a promise that resolves to an array of strings containing the label keys.
*
* @param options - (Optional) An object containing additional options - currently only time range.
* @param options.timeRange - (Optional) The time range for which you want to retrieve label keys. If not provided, the default time range is used.
* @returns A promise containing an array of label keys.
* @throws An error if the fetch operation fails.
*/
private async fetchLabelsByLabelsEndpoint(options?: {
streamSelector?: string;
timeRange?: TimeRange;
}): Promise<string[]> {
const url = 'labels';
const range = options?.timeRange ?? this.getDefaultTimeRange();
const { start, end } = this.datasource.getTimeRangeParams(range);
const params: Record<string, string | number> = { start, end };
if (options?.streamSelector && options?.streamSelector !== EMPTY_SELECTOR) {
params['query'] = options.streamSelector;
}
const res = await this.request(url, params);
if (Array.isArray(res)) {
const labels = Array.from(new Set(res))
.slice()
.sort()
.filter((label: string) => HIDDEN_LABELS.includes(label) === false);
this.labelKeys = labels;
return this.labelKeys;
}
return [];
}
/**
* Fetch series labels for a selector
*
* This method fetches labels for a given stream selector, such as `{job="grafana"}`.
* It returns a promise that resolves to a record mapping label names to their corresponding values.
*
* @param streamSelector - The stream selector for which you want to retrieve labels.
* @param options - (Optional) An object containing additional options - currently only time range.
* @param options.timeRange - (Optional) The time range for which you want to retrieve label keys. If not provided, the default time range is used.
* @returns A promise containing a record of label names and their values.
* @throws An error if the fetch operation fails.
*/
fetchSeriesLabels = async (
streamSelector: string,
options?: { timeRange?: TimeRange }
): Promise<Record<string, string[]>> => {
const interpolatedMatch = this.datasource.interpolateString(streamSelector);
const url = 'series';
const range = options?.timeRange ?? this.getDefaultTimeRange();
const { start, end } = this.datasource.getTimeRangeParams(range);
const cacheKey = this.generateCacheKey(url, start, end, interpolatedMatch);
let value = this.seriesCache.get(cacheKey);
if (!value) {
const params = { 'match[]': interpolatedMatch, start, end };
const data = await this.request(url, params);
if (!Array.isArray(data)) {
return {};
}
const { values } = processLabels(data);
value = values;
this.seriesCache.set(cacheKey, value);
}
return value;
};
/**
* Fetch series for a selector. Use this for raw results. Use fetchSeriesLabels() to get labels.
* @param match
* @param streamSelector - The stream selector for which you want to retrieve labels.
* @param options - (Optional) An object containing additional options.
* @param options.timeRange - (Optional) The time range for which you want to retrieve label keys. If not provided, the default time range is used.
* @returns A promise containing array with records of label names and their value.
*/
fetchSeries = async (match: string, options?: { timeRange?: TimeRange }): Promise<Array<Record<string, string>>> => {
const url = 'series';
const range = options?.timeRange ?? this.getDefaultTimeRange();
const { start, end } = this.datasource.getTimeRangeParams(range);
const params = { 'match[]': match, start, end };
return await this.request(url, params);
};
// Cache key is a bit different here. We round up to a minute the intervals.
// The rounding may seem strange but makes relative intervals like now-1h less prone to need separate request every
// millisecond while still actually getting all the keys for the correct interval. This still can create problems
// when user does not the newest values for a minute if already cached.
private generateCacheKey(url: string, start: number, end: number, param: string): string {
return [url, this.roundTime(start), this.roundTime(end), param].join();
}
// Round nanoseconds epoch to nearest 5 minute interval
private roundTime(nanoseconds: number): number {
return nanoseconds ? Math.floor(nanoseconds / NS_IN_MS / 1000 / 60 / 5) : 0;
}
async fetchDetectedFields(
queryOptions: {
expr: string;
timeRange?: TimeRange;
limit?: number;
scopedVars?: ScopedVars;
},
requestOptions?: Partial<BackendSrvRequest>
): Promise<DetectedFieldsResult | Error> {
const interpolatedExpr =
queryOptions.expr && queryOptions.expr !== EMPTY_SELECTOR
? this.datasource.interpolateString(queryOptions.expr, queryOptions.scopedVars)
: undefined;
if (!interpolatedExpr) {
throw new Error('fetchDetectedFields requires query expression');
}
const url = `detected_fields`;
const range = queryOptions?.timeRange ?? this.getDefaultTimeRange();
const rangeParams = this.datasource.getTimeRangeParams(range);
const { start, end } = rangeParams;
const params: KeyValue<string | number> = { start, end, limit: queryOptions?.limit ?? 1000 };
params.query = interpolatedExpr;
return new Promise(async (resolve, reject) => {
try {
const data = await this.request(url, params, true, requestOptions);
resolve(data);
} catch (error) {
console.error('error', error);
reject(error);
}
});
}
async fetchDetectedFieldValues(
labelName: string,
queryOptions?: {
expr?: string;
timeRange?: TimeRange;
limit?: number;
scopedVars?: ScopedVars;
throwError?: boolean;
},
requestOptions?: Partial<BackendSrvRequest>
): Promise<string[] | Error> {
// This function was named poorly, it's not detected label values, it's detected field values! :facepalm
return this.fetchDetectedLabelValues(labelName, queryOptions, requestOptions);
}
/**
* @deprecated: use fetchDetectedFieldValues instead
*/
async fetchDetectedLabelValues(
labelName: string,
queryOptions?: {
expr?: string;
timeRange?: TimeRange;
limit?: number;
scopedVars?: ScopedVars;
throwError?: boolean;
},
requestOptions?: Partial<BackendSrvRequest>
): Promise<string[] | Error> {
const label = encodeURIComponent(this.datasource.interpolateString(labelName));
const interpolatedExpr =
queryOptions?.expr && queryOptions.expr !== EMPTY_SELECTOR
? this.datasource.interpolateString(queryOptions.expr, queryOptions.scopedVars)
: undefined;
const url = `detected_field/${label}/values`;
const range = queryOptions?.timeRange ?? this.getDefaultTimeRange();
const rangeParams = this.datasource.getTimeRangeParams(range);
const { start, end } = rangeParams;
const params: KeyValue<string | number> = { start, end, limit: queryOptions?.limit ?? 1000 };
let paramCacheKey = label;
if (interpolatedExpr) {
params.query = interpolatedExpr;
paramCacheKey += interpolatedExpr;
}
const cacheKey = this.generateCacheKey(url, start, end, paramCacheKey);
// Values in cache, return
const labelValues = this.detectedFieldValuesCache.get(cacheKey);
if (labelValues) {
return labelValues;
}
// Promise in cache, return
let labelValuesPromise = this.detectedLabelValuesPromisesCache.get(cacheKey);
if (labelValuesPromise) {
return labelValuesPromise;
}
labelValuesPromise = new Promise(async (resolve, reject) => {
try {
const data = await this.request(url, params, queryOptions?.throwError, requestOptions);
if (Array.isArray(data)) {
const labelValues = data.slice().sort();
this.detectedFieldValuesCache.set(cacheKey, labelValues);
this.detectedLabelValuesPromisesCache.delete(cacheKey);
resolve(labelValues);
}
} catch (error) {
if (queryOptions?.throwError) {
reject(error);
} else {
console.error(error);
resolve([]);
}
}
});
this.detectedLabelValuesPromisesCache.set(cacheKey, labelValuesPromise);
return labelValuesPromise;
}
/**
* Fetch label values
*
* This asynchronous function fetches values associated with a specified label name.
* It returns a promise that resolves to an array of strings containing the label values.
*
* @param labelName - The name of the label for which you want to retrieve values.
* @param options - (Optional) An object containing additional options.
* @param options.streamSelector - (Optional) The stream selector to filter label values. If not provided, all label values are fetched.
* @param options.timeRange - (Optional) The time range for which you want to retrieve label values. If not provided, the default time range is used.
* @returns A promise containing an array of label values.
* @throws An error if the fetch operation fails.
*/
async fetchLabelValues(
labelName: string,
options?: { streamSelector?: string; timeRange?: TimeRange }
): Promise<string[]> {
const label = encodeURIComponent(this.datasource.interpolateString(labelName));
// Loki doesn't allow empty streamSelector {}, so we should not send it.
const streamParam =
options?.streamSelector && options.streamSelector !== EMPTY_SELECTOR
? this.datasource.interpolateString(options.streamSelector)
: undefined;
const url = `label/${label}/values`;
const range = options?.timeRange ?? this.getDefaultTimeRange();
const rangeParams = this.datasource.getTimeRangeParams(range);
const { start, end } = rangeParams;
const params: KeyValue<string | number> = { start, end };
let paramCacheKey = label;
if (streamParam) {
params.query = streamParam;
paramCacheKey += streamParam;
}
const cacheKey = this.generateCacheKey(url, start, end, paramCacheKey);
// Values in cache, return
const labelValues = this.labelsCache.get(cacheKey);
if (labelValues) {
return labelValues;
}
// Promise in cache, return
let labelValuesPromise = this.labelsPromisesCache.get(cacheKey);
if (labelValuesPromise) {
return labelValuesPromise;
}
labelValuesPromise = new Promise(async (resolve) => {
try {
const data = await this.request(url, params);
if (Array.isArray(data)) {
const labelValues = data.slice().sort();
this.labelsCache.set(cacheKey, labelValues);
this.labelsPromisesCache.delete(cacheKey);
resolve(labelValues);
}
} catch (error) {
console.error(error);
resolve([]);
}
});
this.labelsPromisesCache.set(cacheKey, labelValuesPromise);
return labelValuesPromise;
}
/**
* Get parser and label keys for a selector
*
* This asynchronous function is used to fetch parsers and label keys for a selected log stream based on sampled lines.
* It returns a promise that resolves to an object with the following properties:
*
* - `extractedLabelKeys`: An array of available label keys associated with the log stream.
* - `hasJSON`: A boolean indicating whether JSON parsing is available for the stream.
* - `hasLogfmt`: A boolean indicating whether Logfmt parsing is available for the stream.
* - `hasPack`: A boolean indicating whether Pack parsing is available for the stream.
* - `unwrapLabelKeys`: An array of label keys that can be used for unwrapping log data.
*
* @param streamSelector - The selector for the log stream you want to analyze.
* @param options - (Optional) An object containing additional options.
* @param options.maxLines - (Optional) The number of log lines requested when determining parsers and label keys.
* @param options.timeRange - (Optional) The time range for which you want to retrieve label keys. If not provided, the default time range is used.
* Smaller maxLines is recommended for improved query performance. The default count is 10.
* @returns A promise containing an object with parser and label key information.
* @throws An error if the fetch operation fails.
*/
async getParserAndLabelKeys(
streamSelector: string,
options?: { maxLines?: number; timeRange?: TimeRange }
): Promise<ParserAndLabelKeysResult> {
const empty = {
extractedLabelKeys: [],
structuredMetadataKeys: [],
unwrapLabelKeys: [],
hasJSON: false,
hasLogfmt: false,
hasPack: false,
};
if (!config.featureToggles.lokiQueryHints) {
return empty;
}
const series = await this.datasource.getDataSamples(
{
expr: streamSelector,
refId: 'data-samples',
maxLines: options?.maxLines || DEFAULT_MAX_LINES_SAMPLE,
},
options?.timeRange ?? this.getDefaultTimeRange()
);
if (!series.length) {
return empty;
}
const { hasLogfmt, hasJSON, hasPack } = extractLogParserFromDataFrame(series[0]);
return {
extractedLabelKeys: [
...extractLabelKeysFromDataFrame(series[0], LabelType.Indexed),
...extractLabelKeysFromDataFrame(series[0], LabelType.Parsed),
],
structuredMetadataKeys: extractLabelKeysFromDataFrame(series[0], LabelType.StructuredMetadata),
unwrapLabelKeys: extractUnwrapLabelKeysFromDataFrame(series[0]),
hasJSON,
hasPack,
hasLogfmt,
};
}
/**
* Get the default time range
*
* @returns {TimeRange} The default time range
*/
private getDefaultTimeRange(): TimeRange {
return getDefaultTimeRange();
}
}