grafana/public/app/plugins/datasource/loki/datasource.ts
Ivana Huckova 0ffd9a9a3c
Loki: Run instant query only in Explore (#27974)
* Run instant query only in Explore

* Replace forEach with for loop
2020-10-04 21:41:12 +02:00

558 lines
19 KiB
TypeScript

// Libraries
import { cloneDeep, isEmpty, map as lodashMap } from 'lodash';
import { merge, Observable, of } from 'rxjs';
import { catchError, map, switchMap } from 'rxjs/operators';
// Types
import {
AnnotationEvent,
AnnotationQueryRequest,
DataFrame,
DataFrameView,
DataQueryError,
DataQueryRequest,
DataQueryResponse,
DataSourceApi,
DataSourceInstanceSettings,
dateMath,
DateTime,
FieldCache,
LoadingState,
LogRowModel,
PluginMeta,
QueryResultMeta,
ScopedVars,
TimeRange,
CoreApp,
} from '@grafana/data';
import { getTemplateSrv, TemplateSrv, BackendSrvRequest, FetchError, getBackendSrv } from '@grafana/runtime';
import { addLabelToQuery } from 'app/plugins/datasource/prometheus/add_label_to_query';
import { getTimeSrv, TimeSrv } from 'app/features/dashboard/services/TimeSrv';
import { convertToWebSocketUrl } from 'app/core/utils/explore';
import { lokiResultsToTableModel, lokiStreamResultToDataFrame, processRangeQueryResponse } from './result_transformer';
import { getHighlighterExpressionsFromQuery } from './query_utils';
import {
LokiOptions,
LokiQuery,
LokiRangeQueryRequest,
LokiResponse,
LokiResultType,
LokiStreamResponse,
} from './types';
import { LiveStreams, LokiLiveTarget } from './live_streams';
import LanguageProvider, { rangeToParams } from './language_provider';
import { serializeParams } from '../../../core/utils/fetch';
import { RowContextOptions } from '@grafana/ui/src/components/Logs/LogRowContextProvider';
export type RangeQueryOptions = DataQueryRequest<LokiQuery> | AnnotationQueryRequest<LokiQuery>;
export const DEFAULT_MAX_LINES = 1000;
export const LOKI_ENDPOINT = '/loki/api/v1';
const RANGE_QUERY_ENDPOINT = `${LOKI_ENDPOINT}/query_range`;
const INSTANT_QUERY_ENDPOINT = `${LOKI_ENDPOINT}/query`;
const DEFAULT_QUERY_PARAMS: Partial<LokiRangeQueryRequest> = {
direction: 'BACKWARD',
limit: DEFAULT_MAX_LINES,
query: '',
};
export class LokiDatasource extends DataSourceApi<LokiQuery, LokiOptions> {
private streams = new LiveStreams();
languageProvider: LanguageProvider;
maxLines: number;
constructor(
private instanceSettings: DataSourceInstanceSettings<LokiOptions>,
private readonly templateSrv: TemplateSrv = getTemplateSrv(),
private readonly timeSrv: TimeSrv = getTimeSrv()
) {
super(instanceSettings);
this.languageProvider = new LanguageProvider(this);
const settingsData = instanceSettings.jsonData || {};
this.maxLines = parseInt(settingsData.maxLines ?? '0', 10) || DEFAULT_MAX_LINES;
}
_request(apiUrl: string, data?: any, options?: Partial<BackendSrvRequest>): Observable<Record<string, any>> {
const baseUrl = this.instanceSettings.url;
const params = data ? serializeParams(data) : '';
const url = `${baseUrl}${apiUrl}${params.length ? `?${params}` : ''}`;
const req = {
...options,
url,
};
return getBackendSrv().fetch<Record<string, any>>(req);
}
query(options: DataQueryRequest<LokiQuery>): Observable<DataQueryResponse> {
const subQueries: Array<Observable<DataQueryResponse>> = [];
const filteredTargets = options.targets
.filter(target => target.expr && !target.hide)
.map(target => ({
...target,
expr: this.templateSrv.replace(target.expr, options.scopedVars, this.interpolateQueryExpr),
}));
for (const target of filteredTargets) {
if (options.app === CoreApp.Explore) {
subQueries.push(this.runInstantQuery(target, options, filteredTargets.length));
}
subQueries.push(this.runRangeQuery(target, options, filteredTargets.length));
}
// No valid targets, return the empty result to save a round trip.
if (isEmpty(subQueries)) {
return of({
data: [],
state: LoadingState.Done,
});
}
return merge(...subQueries);
}
runInstantQuery = (
target: LokiQuery,
options: DataQueryRequest<LokiQuery>,
responseListLength: number
): Observable<DataQueryResponse> => {
const timeNs = this.getTime(options.range.to, true);
const query = {
query: target.expr,
time: `${timeNs + (1e9 - (timeNs % 1e9))}`,
limit: Math.min(options.maxDataPoints || Infinity, this.maxLines),
};
/** Show results of Loki instant queries only in table */
const meta: QueryResultMeta = {
preferredVisualisationType: 'table',
};
return this._request(INSTANT_QUERY_ENDPOINT, query).pipe(
map((response: { data: LokiResponse }) => {
if (response.data.data.resultType === LokiResultType.Stream) {
return {
data: [],
key: `${target.refId}_instant`,
};
}
return {
data: [lokiResultsToTableModel(response.data.data.result, responseListLength, target.refId, meta, true)],
key: `${target.refId}_instant`,
};
}),
catchError((err: any) => this.throwUnless(err, err.status === 404, target))
);
};
createRangeQuery(target: LokiQuery, options: RangeQueryOptions): LokiRangeQueryRequest {
const query = target.expr;
let range: { start?: number; end?: number; step?: number } = {};
if (options.range) {
const startNs = this.getTime(options.range.from, false);
const endNs = this.getTime(options.range.to, true);
const rangeMs = Math.ceil((endNs - startNs) / 1e6);
const step = Math.ceil(
this.adjustInterval((options as DataQueryRequest<LokiQuery>).intervalMs || 1000, rangeMs) / 1000
);
const alignedTimes = {
start: startNs - (startNs % 1e9),
end: endNs + (1e9 - (endNs % 1e9)),
};
range = {
start: alignedTimes.start,
end: alignedTimes.end,
step,
};
}
return {
...DEFAULT_QUERY_PARAMS,
...range,
query,
limit: Math.min((options as DataQueryRequest<LokiQuery>).maxDataPoints || Infinity, this.maxLines),
};
}
/**
* Attempts to send a query to /loki/api/v1/query_range
*/
runRangeQuery = (
target: LokiQuery,
options: RangeQueryOptions,
responseListLength = 1
): Observable<DataQueryResponse> => {
// target.maxLines value already preprocessed
// available cases:
// 1) empty input -> mapped to NaN, falls back to dataSource.maxLines limit
// 2) input with at least 1 character and that is either incorrect (value in the input field is not a number) or negative
// - mapped to 0, falls back to the limit of 0 lines
// 3) default case - correct input, mapped to the value from the input field
let linesLimit = 0;
if (target.maxLines === undefined) {
// no target.maxLines, using options.maxDataPoints
linesLimit = Math.min((options as DataQueryRequest<LokiQuery>).maxDataPoints || Infinity, this.maxLines);
} else {
// using target.maxLines
if (isNaN(target.maxLines)) {
linesLimit = this.maxLines;
} else {
linesLimit = target.maxLines;
}
}
const queryOptions = { ...options, maxDataPoints: linesLimit };
if ((options as DataQueryRequest<LokiQuery>).liveStreaming) {
return this.runLiveQuery(target, queryOptions);
}
const query = this.createRangeQuery(target, queryOptions);
return this._request(RANGE_QUERY_ENDPOINT, query).pipe(
catchError((err: any) => this.throwUnless(err, err.status === 404, target)),
switchMap((response: { data: LokiResponse; status: number }) =>
processRangeQueryResponse(
response.data,
target,
query,
responseListLength,
linesLimit,
this.instanceSettings.jsonData,
(options as DataQueryRequest<LokiQuery>).scopedVars,
(options as DataQueryRequest<LokiQuery>).reverse
)
)
);
};
createLiveTarget(target: LokiQuery, options: { maxDataPoints?: number }): LokiLiveTarget {
const query = target.expr;
const baseUrl = this.instanceSettings.url;
const params = serializeParams({ query });
return {
query,
url: convertToWebSocketUrl(`${baseUrl}/loki/api/v1/tail?${params}`),
refId: target.refId,
size: Math.min(options.maxDataPoints || Infinity, this.maxLines),
};
}
/**
* Runs live queries which in this case means creating a websocket and listening on it for new logs.
* This returns a bit different dataFrame than runQueries as it returns single dataframe even if there are multiple
* Loki streams, sets only common labels on dataframe.labels and has additional dataframe.fields.labels for unique
* labels per row.
*/
runLiveQuery = (target: LokiQuery, options: { maxDataPoints?: number }): Observable<DataQueryResponse> => {
const liveTarget = this.createLiveTarget(target, options);
return this.streams.getStream(liveTarget).pipe(
map(data => ({
data,
key: `loki-${liveTarget.refId}`,
state: LoadingState.Streaming,
}))
);
};
interpolateVariablesInQueries(queries: LokiQuery[], scopedVars: ScopedVars): LokiQuery[] {
let expandedQueries = queries;
if (queries && queries.length) {
expandedQueries = queries.map(query => ({
...query,
datasource: this.name,
expr: this.templateSrv.replace(query.expr, scopedVars, this.interpolateQueryExpr),
}));
}
return expandedQueries;
}
getQueryDisplayText(query: LokiQuery) {
return query.expr;
}
async importQueries(queries: LokiQuery[], originMeta: PluginMeta): Promise<LokiQuery[]> {
return this.languageProvider.importQueries(queries, originMeta.id);
}
async metadataRequest(url: string, params?: Record<string, string | number>) {
const res = await this._request(url, params, { hideFromInspector: true }).toPromise();
return res.data.data || res.data.values || [];
}
async metricFindQuery(query: string, optionalOptions?: any) {
if (!query) {
return Promise.resolve([]);
}
const interpolated = this.templateSrv.replace(query, {}, this.interpolateQueryExpr);
return await this.processMetricFindQuery(interpolated, optionalOptions?.range);
}
async processMetricFindQuery(query: string, range?: TimeRange) {
const labelNamesRegex = /^label_names\(\)\s*$/;
const labelValuesRegex = /^label_values\((?:(.+),\s*)?([a-zA-Z_][a-zA-Z0-9_]*)\)\s*$/;
const timeRange = range || this.timeSrv.timeRange();
const params = rangeToParams({ from: timeRange.from.valueOf(), to: timeRange.to.valueOf() });
const labelNames = query.match(labelNamesRegex);
if (labelNames) {
return await this.labelNamesQuery(params);
}
const labelValues = query.match(labelValuesRegex);
if (labelValues) {
return await this.labelValuesQuery(labelValues[2], params);
}
return Promise.resolve([]);
}
async labelNamesQuery(params?: Record<string, string | number>) {
const url = `${LOKI_ENDPOINT}/label`;
const result = await this.metadataRequest(url, params);
return result.map((value: string) => ({ text: value }));
}
async labelValuesQuery(label: string, params?: Record<string, string | number>) {
const url = `${LOKI_ENDPOINT}/label/${label}/values`;
const result = await this.metadataRequest(url, params);
return result.map((value: string) => ({ text: value }));
}
interpolateQueryExpr(value: any, variable: any) {
// if no multi or include all do not regexEscape
if (!variable.multi && !variable.includeAll) {
return lokiRegularEscape(value);
}
if (typeof value === 'string') {
return lokiSpecialRegexEscape(value);
}
const escapedValues = lodashMap(value, lokiSpecialRegexEscape);
return escapedValues.join('|');
}
modifyQuery(query: LokiQuery, action: any): LokiQuery {
let expression = query.expr ?? '';
switch (action.type) {
case 'ADD_FILTER': {
expression = addLabelToQuery(expression, action.key, action.value, undefined, true);
break;
}
case 'ADD_FILTER_OUT': {
expression = addLabelToQuery(expression, action.key, action.value, '!=', true);
break;
}
default:
break;
}
return { ...query, expr: expression };
}
getHighlighterExpression(query: LokiQuery): string[] {
return getHighlighterExpressionsFromQuery(query.expr);
}
getTime(date: string | DateTime, roundUp: boolean) {
if (typeof date === 'string') {
date = dateMath.parse(date, roundUp)!;
}
return Math.ceil(date.valueOf() * 1e6);
}
getLogRowContext = (row: LogRowModel, options?: RowContextOptions): Promise<{ data: DataFrame[] }> => {
const target = this.prepareLogRowContextQueryTarget(
row,
(options && options.limit) || 10,
(options && options.direction) || 'BACKWARD'
);
const reverse = options && options.direction === 'FORWARD';
return this._request(RANGE_QUERY_ENDPOINT, target)
.pipe(
catchError((err: any) => {
if (err.status === 404) {
return of(err);
}
const error: DataQueryError = {
message: 'Error during context query. Please check JS console logs.',
status: err.status,
statusText: err.statusText,
};
throw error;
}),
switchMap((res: { data: LokiStreamResponse; status: number }) =>
of({
data: res.data ? res.data.data.result.map(stream => lokiStreamResultToDataFrame(stream, reverse)) : [],
})
)
)
.toPromise();
};
prepareLogRowContextQueryTarget = (row: LogRowModel, limit: number, direction: 'BACKWARD' | 'FORWARD') => {
const query = Object.keys(row.labels)
.map(label => `${label}="${row.labels[label].replace(/\\/g, '\\\\')}"`) // escape backslashes in label as users can't escape them by themselves
.join(',');
const contextTimeBuffer = 2 * 60 * 60 * 1000; // 2h buffer
const commonTargetOptions = {
limit,
query: `{${query}}`,
expr: `{${query}}`,
direction,
};
const fieldCache = new FieldCache(row.dataFrame);
const nsField = fieldCache.getFieldByName('tsNs')!;
const nsTimestamp = nsField.values.get(row.rowIndex);
if (direction === 'BACKWARD') {
return {
...commonTargetOptions,
// convert to ns, we loose some precision here but it is not that important at the far points of the context
start: row.timeEpochMs - contextTimeBuffer + '000000',
end: nsTimestamp,
direction,
};
} else {
return {
...commonTargetOptions,
// start param in Loki API is inclusive so we'll have to filter out the row that this request is based from
// and any other that were logged in the same ns but before the row. Right now these rows will be lost
// because the are before but came it he response that should return only rows after.
start: nsTimestamp,
// convert to ns, we loose some precision here but it is not that important at the far points of the context
end: row.timeEpochMs + contextTimeBuffer + '000000',
};
}
};
testDatasource() {
// Consider only last 10 minutes otherwise request takes too long
const startMs = Date.now() - 10 * 60 * 1000;
const start = `${startMs}000000`; // API expects nanoseconds
return this._request(`${LOKI_ENDPOINT}/label`, { start })
.pipe(
map(res => {
const values: any[] = res?.data?.data || res?.data?.values || [];
const testResult =
values.length > 0
? { status: 'success', message: 'Data source connected and labels found.' }
: {
status: 'error',
message:
'Data source connected, but no labels received. Verify that Loki and Promtail is configured properly.',
};
return testResult;
}),
catchError((err: any) => {
let message = 'Loki: ';
if (err.statusText) {
message += err.statusText;
} else {
message += 'Cannot connect to Loki';
}
if (err.status) {
message += `. ${err.status}`;
}
if (err.data && err.data.message) {
message += `. ${err.data.message}`;
} else if (err.data) {
message += `. ${err.data}`;
}
return of({ status: 'error', message: message });
})
)
.toPromise();
}
async annotationQuery(options: AnnotationQueryRequest<LokiQuery>): Promise<AnnotationEvent[]> {
if (!options.annotation.expr) {
return [];
}
const interpolatedExpr = this.templateSrv.replace(options.annotation.expr, {}, this.interpolateQueryExpr);
const query = { refId: `annotation-${options.annotation.name}`, expr: interpolatedExpr };
const { data } = await this.runRangeQuery(query, options as any).toPromise();
const annotations: AnnotationEvent[] = [];
for (const frame of data) {
const tags: string[] = [];
for (const field of frame.fields) {
if (field.labels) {
tags.push.apply(tags, [...new Set(Object.values(field.labels).map((label: string) => label.trim()))]);
}
}
const view = new DataFrameView<{ ts: string; line: string }>(frame);
view.forEach(row => {
annotations.push({
time: new Date(row.ts).valueOf(),
text: row.line,
tags,
});
});
}
return annotations;
}
showContextToggle(row?: LogRowModel): boolean {
return (row && row.searchWords && row.searchWords.length > 0) === true;
}
throwUnless(err: FetchError, condition: boolean, target: LokiQuery) {
if (condition) {
return of(err);
}
const error = this.processError(err, target);
throw error;
}
processError(err: FetchError, target: LokiQuery) {
let error = cloneDeep(err);
if (err.data.message.includes('escape') && target.expr.includes('\\')) {
error.data.message = `Error: ${err.data.message}. Make sure that all special characters are escaped with \\. For more information on escaping of special characters visit LogQL documentation at https://github.com/grafana/loki/blob/master/docs/logql.md.`;
}
return error;
}
adjustInterval(interval: number, range: number) {
// Loki will drop queries that might return more than 11000 data points.
// Calibrate interval if it is too small.
if (interval !== 0 && range / interval > 11000) {
interval = Math.ceil(range / 11000);
}
return Math.max(interval, 1000);
}
}
export function lokiRegularEscape(value: any) {
if (typeof value === 'string') {
return value.replace(/'/g, "\\\\'");
}
return value;
}
export function lokiSpecialRegexEscape(value: any) {
if (typeof value === 'string') {
return lokiRegularEscape(value.replace(/\\/g, '\\\\\\\\').replace(/[$^*{}\[\]+?.()|]/g, '\\\\$&'));
}
return value;
}
export default LokiDatasource;