fix: make no data look like no data (#8396)

This PR adjusts what we show for no data to make it clearer that we
actually have no data.

It also makes the graph slightly smaller.


![image](https://github.com/user-attachments/assets/12a009a6-a24d-4821-bb03-c408417011a7)

frontend/src/component/personalDashboard/FlagMetricsChart.tsx

@@ -11,7 +11,7 @@ import annotationPlugin from 'chartjs-plugin-annotation';
 import { Bar } from 'react-chartjs-2';
 import useTheme from '@mui/material/styles/useTheme';
 import { type FC, useEffect, useMemo, useState } from 'react';
-import { Box, styled, Typography } from '@mui/material';
+import { Box, styled } from '@mui/material';
 import { FeatureMetricsHours } from '../feature/FeatureView/FeatureMetrics/FeatureMetricsHours/FeatureMetricsHours';
 import GeneralSelect from '../common/GeneralSelect/GeneralSelect';
 import { useFeatureMetricsRaw } from 'hooks/api/getters/useFeatureMetricsRaw/useFeatureMetricsRaw';
@@ -24,39 +24,24 @@ import {
 } from './createChartOptions';
 import { useFeature } from 'hooks/api/getters/useFeature/useFeature';
 
-const defaultYes = [
-    45_000_000, 28_000_000, 28_000_000, 25_000_000, 50_000_000, 27_000_000,
-    26_000_000, 50_000_000, 32_000_000, 12_000_000, 13_000_000, 31_000_000,
-    12_000_000, 47_000_000, 29_000_000, 46_000_000, 45_000_000, 28_000_000,
-    28_000_000, 25_000_000, 50_000_000, 27_000_000, 26_000_000, 50_000_000,
-    32_000_000, 12_000_000, 13_000_000, 31_000_000, 12_000_000, 47_000_000,
-];
-const defaultNo = [
-    5_000_000, 8_000_000, 3_000_000, 2_000_000, 2_000_000, 5_000_000, 9_000_000,
-    3_000_000, 7_000_000, 2_000_000, 5_000_000, 8_000_000, 3_000_000, 2_000_000,
-    2_000_000, 5_000_000, 1_000_000, 3_000_000, 12_000_000, 2_000_000,
-    1_000_000, 1_000_000, 3_000_000, 2_000_000, 2_000_000, 5_000_000, 1_000_000,
-    3_000_000, 8_000_000, 2_000_000,
-];
+const defaultYes = [0, 14, 28, 21, 33, 31, 31, 22, 26, 37, 31, 14, 21, 14, 0];
 
 const placeholderData = {
-    labels: Array.from({ length: 30 }, (_, i) => i + 1),
+    labels: Array.from({ length: 15 }, (_, i) => i + 1),
     datasets: [
         {
             data: defaultYes,
-            label: 'yes',
-            backgroundColor: '#BEBEBE',
-            hoverBackgroundColor: '#BEBEBE',
-        },
-        {
-            data: defaultNo,
-            label: 'no',
-            backgroundColor: '#9A9A9A',
-            hoverBackgroundColor: '#9A9A9A',
+            backgroundColor: '#EAEAED',
+            hoverBackgroundColor: '#EAEAED',
+            label: 'No metrics for this feature flag in the selected environment and time period',
         },
     ],
 };
 
+const ChartWrapper = styled('div')({
+    width: '90%',
+});
+
 export const PlaceholderFlagMetricsChart = () => {
     const theme = useTheme();
 
@@ -65,14 +50,13 @@ export const PlaceholderFlagMetricsChart = () => {
     }, [theme]);
 
     return (
-        <>
-            <Typography sx={{ mb: 4 }}>No feature flag metrics data</Typography>
+        <ChartWrapper>
             <Bar
                 data={placeholderData}
                 options={options}
                 aria-label='A placeholder bar chart with a single feature flag exposure metrics'
             />
-        </>
+        </ChartWrapper>
     );
 };
 
@@ -160,7 +144,14 @@ const MetricsSelectors = styled(Box)(({ theme }) => ({
     display: 'flex',
     justifyContent: 'flex-end',
     gap: theme.spacing(2),
-    mb: theme.spacing(6),
+    width: '100%',
+}));
+
+const ChartContainer = styled('div')(({ theme }) => ({
+    display: 'flex',
+    flexDirection: 'column',
+    gap: theme.spacing(3),
+    alignItems: 'center',
 }));
 
 export const FlagMetricsChart: FC<{
@@ -176,7 +167,7 @@ export const FlagMetricsChart: FC<{
     const noData = data.datasets[0].data.length === 0;
 
     return (
-        <>
+        <ChartContainer>
             <MetricsSelectors>
                 {environment ? (
                     <EnvironmentSelect
@@ -194,13 +185,15 @@ export const FlagMetricsChart: FC<{
             {noData ? (
                 <PlaceholderFlagMetricsChart />
             ) : (
-                <Bar
-                    data={data}
-                    options={options}
-                    aria-label='A bar chart with a single feature flag exposure metrics'
-                />
+                <ChartWrapper>
+                    <Bar
+                        data={data}
+                        options={options}
+                        aria-label='A bar chart with a single feature flag exposure metrics'
+                    />
+                </ChartWrapper>
             )}
-        </>
+        </ChartContainer>
     );
 };
 

frontend/src/component/personalDashboard/PersonalDashboard.test.tsx

@@ -145,7 +145,6 @@ test('Render personal dashboard for a long running project', async () => {
     await screen.findByText('13 feature flags'); // stale flags
     await screen.findByText('14 feature flags'); // potentially stale flags
     await screen.findByText('myFlag');
-    await screen.findByText('No feature flag metrics data');
     await screen.findByText('production');
     await screen.findByText('Last 48 hours');
 });
@@ -166,6 +165,4 @@ test('Render personal dashboard for a new project', async () => {
     await screen.findByText(
         'You have not created or favorited any feature flags. Once you do, they will show up here.',
     );
-
-    await screen.findByText('No feature flag metrics data');
 });

frontend/src/component/personalDashboard/createChartOptions.ts

@@ -1,6 +1,5 @@
 import type { Theme } from '@mui/material/styles/createTheme';
 import type { ChartOptions } from 'chart.js';
-import { formatTickValue } from '../common/Chart/formatTickValue';
 import type { ILocationSettings } from '../../hooks/useLocationSettings';
 import type { IPoint } from '../feature/FeatureView/FeatureMetrics/FeatureMetricsChart/createChartData';
 import {
@@ -24,16 +23,17 @@ export const createPlaceholderBarChartOptions = (
 ): ChartOptions<'bar'> => ({
     plugins: {
         legend: {
-            position: 'bottom',
+            position: 'top',
             labels: {
                 color: theme.palette.text.primary,
-                pointStyle: 'circle',
                 usePointStyle: true,
-                boxHeight: 6,
+                pointStyle: 'none',
+                boxHeight: 0,
                 padding: 15,
                 boxPadding: 5,
             },
         },
+
         tooltip: {
             enabled: false,
         },
@@ -43,7 +43,7 @@ export const createPlaceholderBarChartOptions = (
         x: {
             stacked: true,
             ticks: {
-                color: theme.palette.text.secondary,
+                display: false,
             },
             grid: {
                 display: false,
@@ -52,9 +52,8 @@ export const createPlaceholderBarChartOptions = (
         y: {
             stacked: true,
             ticks: {
-                color: theme.palette.text.secondary,
                 maxTicksLimit: 5,
-                callback: formatTickValue,
+                display: false,
             },
             grid: {
                 drawBorder: false,
@@ -77,11 +76,22 @@ export const createBarChartOptions = (
     hoursBack: number,
     locationSettings: ILocationSettings,
 ): ChartOptions<'bar'> => {
-    const { plugins, responsive, elements, interaction, scales } =
+    const { responsive, elements, interaction, scales } =
         createPlaceholderBarChartOptions(theme);
     return {
         plugins: {
-            legend: plugins?.legend,
+            legend: {
+                position: 'bottom',
+                labels: {
+                    color: theme.palette.text.primary,
+                    pointStyle: 'circle',
+                    usePointStyle: true,
+                    boxHeight: 6,
+                    padding: 15,
+                    boxPadding: 5,
+                },
+            },
+
             // required to avoid the highlight plugin highlighting empty annotation
             annotation: {
                 clip: false,