From caa82a124daaf87c648fb194f3fc1770373f824c Mon Sep 17 00:00:00 2001
From: Ivana Huckova <30407135+ivanahuckova@users.noreply.github.com>
Date: Wed, 6 Apr 2022 11:17:49 +0200
Subject: [PATCH] Loki,Prometheus: Fix of showing error message for empty query
 (#47379)

* Loki,Prometheus: Dont show error on empty query

* Add tests
---
 .../loki/querybuilder/parsing.test.ts         |  9 ++++++
 .../datasource/loki/querybuilder/parsing.ts   | 28 ++++++++++++++++---
 .../prometheus/querybuilder/parsing.test.ts   |  9 ++++++
 .../prometheus/querybuilder/parsing.ts        | 12 ++++++++
 .../querybuilder/shared/parsingUtils.ts       |  2 +-
 5 files changed, 55 insertions(+), 5 deletions(-)

diff --git a/public/app/plugins/datasource/loki/querybuilder/parsing.test.ts b/public/app/plugins/datasource/loki/querybuilder/parsing.test.ts
index c3b94525519..51201da9d36 100644
--- a/public/app/plugins/datasource/loki/querybuilder/parsing.test.ts
+++ b/public/app/plugins/datasource/loki/querybuilder/parsing.test.ts
@@ -2,6 +2,15 @@ import { buildVisualQueryFromString } from './parsing';
 import { LokiVisualQuery } from './types';
 
 describe('buildVisualQueryFromString', () => {
+  it('creates no errors for empty query', () => {
+    expect(buildVisualQueryFromString('')).toEqual(
+      noErrors({
+        labels: [],
+        operations: [],
+      })
+    );
+  });
+
   it('parses simple query with label-values', () => {
     expect(buildVisualQueryFromString('{app="frontend"}')).toEqual(
       noErrors({
diff --git a/public/app/plugins/datasource/loki/querybuilder/parsing.ts b/public/app/plugins/datasource/loki/querybuilder/parsing.ts
index 3b19dbfe863..43168019c2e 100644
--- a/public/app/plugins/datasource/loki/querybuilder/parsing.ts
+++ b/public/app/plugins/datasource/loki/querybuilder/parsing.ts
@@ -20,8 +20,8 @@ interface Context {
 
 interface ParsingError {
   text: string;
-  from: number;
-  to: number;
+  from?: number;
+  to?: number;
   parentType?: string;
 }
 
@@ -36,12 +36,25 @@ export function buildVisualQueryFromString(expr: string): Context {
     operations: [],
   };
 
-  const context = {
+  const context: Context = {
     query: visQuery,
     errors: [],
   };
 
-  handleExpression(replacedExpr, node, context);
+  try {
+    handleExpression(replacedExpr, node, context);
+  } catch (err) {
+    // Not ideal to log it here, but otherwise we would lose the stack trace.
+    console.error(err);
+    context.errors.push({
+      text: err.message,
+    });
+  }
+
+  // If we have empty query, we want to reset errors
+  if (isEmptyQuery(context.query)) {
+    context.errors = [];
+  }
   return context;
 }
 
@@ -496,3 +509,10 @@ function createNotSupportedError(expr: string, node: SyntaxNode, error: string)
   err.text = `${error}: ${err.text}`;
   return err;
 }
+
+function isEmptyQuery(query: LokiVisualQuery) {
+  if (query.labels.length === 0 && query.operations.length === 0) {
+    return true;
+  }
+  return false;
+}
diff --git a/public/app/plugins/datasource/prometheus/querybuilder/parsing.test.ts b/public/app/plugins/datasource/prometheus/querybuilder/parsing.test.ts
index fc7ffb8142c..a340f44fb63 100644
--- a/public/app/plugins/datasource/prometheus/querybuilder/parsing.test.ts
+++ b/public/app/plugins/datasource/prometheus/querybuilder/parsing.test.ts
@@ -2,6 +2,15 @@ import { buildVisualQueryFromString } from './parsing';
 import { PromVisualQuery } from './types';
 
 describe('buildVisualQueryFromString', () => {
+  it('creates no errors for empty query', () => {
+    expect(buildVisualQueryFromString('')).toEqual(
+      noErrors({
+        labels: [],
+        operations: [],
+        metric: '',
+      })
+    );
+  });
   it('parses simple query', () => {
     expect(buildVisualQueryFromString('counters_logins{app="frontend"}')).toEqual(
       noErrors({
diff --git a/public/app/plugins/datasource/prometheus/querybuilder/parsing.ts b/public/app/plugins/datasource/prometheus/querybuilder/parsing.ts
index 0db720b4b0f..0db7f39daed 100644
--- a/public/app/plugins/datasource/prometheus/querybuilder/parsing.ts
+++ b/public/app/plugins/datasource/prometheus/querybuilder/parsing.ts
@@ -46,6 +46,11 @@ export function buildVisualQueryFromString(expr: string): Context {
       text: err.message,
     });
   }
+
+  // If we have empty query, we want to reset errors
+  if (isEmptyQuery(context.query)) {
+    context.errors = [];
+  }
   return context;
 }
 
@@ -373,3 +378,10 @@ function getBinaryModifier(
     };
   }
 }
+
+function isEmptyQuery(query: PromVisualQuery) {
+  if (query.labels.length === 0 && query.operations.length === 0 && !query.metric) {
+    return true;
+  }
+  return false;
+}
diff --git a/public/app/plugins/datasource/prometheus/querybuilder/shared/parsingUtils.ts b/public/app/plugins/datasource/prometheus/querybuilder/shared/parsingUtils.ts
index 9895860e27e..e2d89d4db6d 100644
--- a/public/app/plugins/datasource/prometheus/querybuilder/shared/parsingUtils.ts
+++ b/public/app/plugins/datasource/prometheus/querybuilder/shared/parsingUtils.ts
@@ -30,7 +30,7 @@ export function makeError(expr: string, node: SyntaxNode) {
 const variableRegex = /\$(\w+)|\[\[([\s\S]+?)(?::(\w+))?\]\]|\${(\w+)(?:\.([^:^\}]+))?(?::([^\}]+))?}/g;
 
 /**
- * As variables with $ are creating parsing errors, we first replace them with magic string that is parseable and at
+ * As variables with $ are creating parsing errors, we first replace them with magic string that is parsable and at
  * the same time we can get the variable and it's format back from it.
  * @param expr
  */