483 lines
18 KiB
JavaScript
483 lines
18 KiB
JavaScript
const express = require('express');
|
||
const cors = require('cors');
|
||
const { createCanvas } = require('@napi-rs/canvas');
|
||
const echarts = require('echarts');
|
||
const path = require('path');
|
||
|
||
const app = express();
|
||
const PORT = process.env.PORT || 16016;
|
||
|
||
// 中间件
|
||
app.use(cors());
|
||
app.use(express.json({ limit: '10mb' }));
|
||
app.use(express.urlencoded({ extended: true, limit: '10mb' }));
|
||
|
||
// 静态文件（前端页面）
|
||
app.use(express.static(path.join(__dirname)));
|
||
|
||
// ===== 预设颜色方案 =====
|
||
const colorPalettes = {
|
||
default: ['#5470c6', '#91cc75', '#fac858', '#ee6666', '#73c0de', '#3ba272', '#fc8452', '#9a60b4', '#ea7ccc'],
|
||
dark: ['#4fc3f7', '#81c784', '#fff176', '#ff8a65', '#ba68c8', '#4dd0e1', '#ffab91', '#aed581', '#f48fb1'],
|
||
macarons: ['#2ec7c9', '#b6a2de', '#5ab1ef', '#ffb980', '#d87a80', '#8d98b3', '#e5cf0d', '#97b552', '#95706d'],
|
||
gradient: ['#7f7fd5', '#86a8e7', '#91eae4', '#ff6b6b', '#feca57', '#48dbfb', '#ff9ff3', '#54a0ff', '#5f27cd'],
|
||
retro: ['#d4a5a5', '#95b9c7', '#f6e8c3', '#dfceb4', '#a4c3b5', '#c9b1ff', '#f5c7b8', '#b8d4e3', '#e8c8a0']
|
||
};
|
||
|
||
// ===== 数据解析（与前端一致） =====
|
||
function parseData(rawText) {
|
||
const lines = rawText.trim().split('\n').filter(l => l.trim());
|
||
if (lines.length < 2) {
|
||
throw new Error('数据至少需要包含表头和一行数据');
|
||
}
|
||
|
||
// 自动检测分隔符
|
||
let delimiter = ',';
|
||
if (lines[0].includes('\t')) {
|
||
delimiter = '\t';
|
||
} else if (lines[0].split('|').length > lines[0].split(',').length) {
|
||
delimiter = '|';
|
||
}
|
||
|
||
const rows = lines.map(line => {
|
||
return line.split(delimiter).map(cell => cell.trim());
|
||
});
|
||
|
||
const headers = rows[0];
|
||
const categories = [];
|
||
const seriesData = {};
|
||
|
||
for (let i = 1; i < headers.length; i++) {
|
||
seriesData[headers[i]] = [];
|
||
}
|
||
|
||
for (let i = 1; i < rows.length; i++) {
|
||
categories.push(rows[i][0]);
|
||
for (let j = 1; j < rows[i].length && j < headers.length; j++) {
|
||
const val = parseFloat(rows[i][j]);
|
||
seriesData[headers[j]].push(isNaN(val) ? 0 : val);
|
||
}
|
||
}
|
||
|
||
return {
|
||
categories,
|
||
seriesNames: headers.slice(1),
|
||
seriesData
|
||
};
|
||
}
|
||
|
||
// ===== 颜色工具 =====
|
||
function adjustColor(hex, amount) {
|
||
hex = hex.replace('#', '');
|
||
const num = parseInt(hex, 16);
|
||
let r = Math.min(255, ((num >> 16) & 0xff) + amount);
|
||
let g = Math.min(255, ((num >> 8) & 0xff) + amount);
|
||
let b = Math.min(255, (num & 0xff) + amount);
|
||
return `rgb(${r},${g},${b})`;
|
||
}
|
||
|
||
// ===== 构建 ECharts option =====
|
||
function buildChartOption(params) {
|
||
const {
|
||
data,
|
||
chartType = 'bar',
|
||
title = '',
|
||
theme = 'default',
|
||
showLegend = true,
|
||
showGrid = true,
|
||
showLabel = false,
|
||
stackMode = false,
|
||
smoothLine = true,
|
||
enableSplit = false,
|
||
splitIndex = 3,
|
||
leftLabel = '左侧',
|
||
rightLabel = '右侧',
|
||
splitStyle = 'solid',
|
||
seriesColors: customColors = null
|
||
} = params;
|
||
|
||
const parsedData = parseData(data);
|
||
const palette = colorPalettes[theme] || colorPalettes.default;
|
||
const seriesColorsArr = customColors || parsedData.seriesNames.map((_, i) => palette[i % palette.length]);
|
||
|
||
// 背景色和文字色
|
||
const bgColor = theme === 'dark' ? '#1a1a2e' : '#ffffff';
|
||
const textColor = theme === 'dark' ? '#e0e0e0' : '#333333';
|
||
const axisLineColor = theme === 'dark' ? '#444' : '#ddd';
|
||
|
||
// 构建系列
|
||
const series = parsedData.seriesNames.map((name, idx) => {
|
||
const dataArr = parsedData.seriesData[name];
|
||
const color = seriesColorsArr[idx] || palette[idx % palette.length];
|
||
|
||
let type = chartType === 'bar-line'
|
||
? (idx % 2 === 0 ? 'bar' : 'line')
|
||
: chartType;
|
||
|
||
const seriesItem = {
|
||
name: name,
|
||
type: type,
|
||
data: [...dataArr],
|
||
itemStyle: { color: color },
|
||
emphasis: {
|
||
focus: 'series',
|
||
itemStyle: {
|
||
shadowBlur: 10,
|
||
shadowColor: 'rgba(0,0,0,0.3)'
|
||
}
|
||
}
|
||
};
|
||
|
||
if (stackMode) {
|
||
seriesItem.stack = 'total';
|
||
}
|
||
|
||
if (type === 'line') {
|
||
seriesItem.smooth = smoothLine;
|
||
seriesItem.lineStyle = { width: 3 };
|
||
seriesItem.symbolSize = 8;
|
||
seriesItem.areaStyle = theme === 'gradient' ? { opacity: 0.15 } : undefined;
|
||
}
|
||
|
||
if (type === 'bar') {
|
||
seriesItem.barMaxWidth = 40;
|
||
seriesItem.itemStyle.borderRadius = stackMode ? [0, 0, 0, 0] : [4, 4, 0, 0];
|
||
}
|
||
|
||
if (showLabel) {
|
||
seriesItem.label = {
|
||
show: true,
|
||
position: 'top',
|
||
fontSize: 11,
|
||
color: textColor,
|
||
formatter: (p) => {
|
||
if (p.value >= 10000) return (p.value / 10000).toFixed(1) + 'w';
|
||
if (p.value >= 1000) return (p.value / 1000).toFixed(1) + 'k';
|
||
return p.value;
|
||
}
|
||
};
|
||
}
|
||
|
||
return seriesItem;
|
||
});
|
||
|
||
// 区域分割
|
||
if (enableSplit && splitIndex < parsedData.categories.length && series.length > 0) {
|
||
const splitLineColor = theme === 'dark' ? '#ff6b6b' : '#e74c3c';
|
||
series[0].markArea = {
|
||
silent: true,
|
||
data: [
|
||
[
|
||
{
|
||
name: leftLabel,
|
||
xAxis: parsedData.categories[0],
|
||
itemStyle: {
|
||
color: theme === 'dark' ? 'rgba(79,195,247,0.06)' : 'rgba(79,70,229,0.05)',
|
||
borderWidth: 0
|
||
},
|
||
label: {
|
||
show: true,
|
||
position: 'insideTop',
|
||
fontSize: 13,
|
||
fontWeight: 'bold',
|
||
color: theme === 'dark' ? '#4fc3f7' : '#4f46e5',
|
||
offset: [0, 10]
|
||
}
|
||
},
|
||
{ xAxis: parsedData.categories[splitIndex - 1] }
|
||
],
|
||
[
|
||
{
|
||
name: rightLabel,
|
||
xAxis: parsedData.categories[splitIndex],
|
||
itemStyle: {
|
||
color: theme === 'dark' ? 'rgba(255,107,107,0.06)' : 'rgba(239,68,68,0.05)',
|
||
borderWidth: 0
|
||
},
|
||
label: {
|
||
show: true,
|
||
position: 'insideTop',
|
||
fontSize: 13,
|
||
fontWeight: 'bold',
|
||
color: theme === 'dark' ? '#ff6b6b' : '#ef4444',
|
||
offset: [0, 10]
|
||
}
|
||
},
|
||
{ xAxis: parsedData.categories[parsedData.categories.length - 1] }
|
||
]
|
||
]
|
||
};
|
||
}
|
||
|
||
// 完整 option
|
||
const option = {
|
||
backgroundColor: bgColor,
|
||
title: title ? {
|
||
text: title,
|
||
left: 'center',
|
||
top: 15,
|
||
textStyle: {
|
||
color: textColor,
|
||
fontSize: 18,
|
||
fontWeight: 600
|
||
}
|
||
} : undefined,
|
||
tooltip: { show: false },
|
||
legend: showLegend ? {
|
||
show: true,
|
||
top: title ? 50 : 15,
|
||
textStyle: { color: textColor, fontSize: 12 },
|
||
itemGap: 20,
|
||
icon: 'roundRect'
|
||
} : { show: false },
|
||
grid: {
|
||
left: '3%',
|
||
right: '4%',
|
||
bottom: '3%',
|
||
top: showLegend ? (title ? 90 : 60) : (title ? 60 : 30),
|
||
containLabel: true
|
||
},
|
||
xAxis: {
|
||
type: 'category',
|
||
data: parsedData.categories,
|
||
axisLine: { lineStyle: { color: axisLineColor } },
|
||
axisLabel: {
|
||
color: textColor,
|
||
fontSize: 12,
|
||
interval: 0,
|
||
rotate: parsedData.categories.length > 10 ? 30 : 0
|
||
},
|
||
axisTick: { show: false }
|
||
},
|
||
yAxis: {
|
||
type: 'value',
|
||
axisLine: { show: false },
|
||
axisTick: { show: false },
|
||
axisLabel: { color: textColor, fontSize: 11 },
|
||
splitLine: {
|
||
show: showGrid,
|
||
lineStyle: {
|
||
color: theme === 'dark' ? '#333' : '#f0f0f0',
|
||
type: 'dashed'
|
||
}
|
||
}
|
||
},
|
||
series: series,
|
||
animation: false // 服务端渲染关闭动画
|
||
};
|
||
|
||
return option;
|
||
}
|
||
|
||
// ===== API: 生成图表图片 =====
|
||
app.post('/api/chart', (req, res) => {
|
||
try {
|
||
const params = req.body;
|
||
|
||
if (!params.data) {
|
||
return res.status(400).json({ error: '缺少 data 参数（CSV 格式数据）' });
|
||
}
|
||
|
||
const width = parseInt(params.width) || 800;
|
||
const height = parseInt(params.height) || 500;
|
||
const format = params.format || 'png';
|
||
const pixelRatio = parseInt(params.pixelRatio) || 2;
|
||
|
||
// 构建图表配置
|
||
const option = buildChartOption(params);
|
||
|
||
// 创建 canvas 并渲染
|
||
const canvas = createCanvas(width * pixelRatio, height * pixelRatio);
|
||
const chart = echarts.init(canvas, null, {
|
||
renderer: 'canvas',
|
||
width: width,
|
||
height: height,
|
||
devicePixelRatio: pixelRatio
|
||
});
|
||
|
||
chart.setOption(option);
|
||
|
||
// 输出图片
|
||
if (format === 'svg') {
|
||
// SVG 需要用 SVG 渲染器重新渲染
|
||
// node-canvas 不支持 SVG，返回 PNG 并提示
|
||
const buffer = canvas.toBuffer('image/png');
|
||
res.set({
|
||
'Content-Type': 'image/png',
|
||
'Content-Length': buffer.length,
|
||
'X-Chart-Format': 'png',
|
||
'X-Chart-Note': 'SVG format not supported in server-side rendering, returned PNG instead'
|
||
});
|
||
res.send(buffer);
|
||
} else {
|
||
const buffer = canvas.toBuffer('image/png');
|
||
res.set({
|
||
'Content-Type': 'image/png',
|
||
'Content-Length': buffer.length,
|
||
'X-Chart-Width': width,
|
||
'X-Chart-Height': height,
|
||
'X-Chart-Pixel-Ratio': pixelRatio
|
||
});
|
||
res.send(buffer);
|
||
}
|
||
|
||
chart.dispose();
|
||
} catch (err) {
|
||
console.error('Chart generation error:', err);
|
||
res.status(500).json({ error: '图表生成失败: ' + err.message });
|
||
}
|
||
});
|
||
|
||
// ===== API: 生成图表（GET 方式，方便 URL 直接调用） =====
|
||
app.get('/api/chart', (req, res) => {
|
||
try {
|
||
const params = {
|
||
data: req.query.data,
|
||
chartType: req.query.chartType || req.query.type || 'bar',
|
||
title: req.query.title || '',
|
||
theme: req.query.theme || 'default',
|
||
showLegend: req.query.showLegend !== 'false',
|
||
showGrid: req.query.showGrid !== 'false',
|
||
showLabel: req.query.showLabel === 'true',
|
||
stackMode: req.query.stackMode === 'true',
|
||
smoothLine: req.query.smoothLine !== 'false',
|
||
enableSplit: req.query.enableSplit === 'true',
|
||
splitIndex: parseInt(req.query.splitIndex) || 3,
|
||
leftLabel: req.query.leftLabel || '左侧',
|
||
rightLabel: req.query.rightLabel || '右侧',
|
||
splitStyle: req.query.splitStyle || 'solid',
|
||
width: parseInt(req.query.width) || 800,
|
||
height: parseInt(req.query.height) || 500,
|
||
format: req.query.format || 'png',
|
||
pixelRatio: parseInt(req.query.pixelRatio) || 2
|
||
};
|
||
|
||
if (!params.data) {
|
||
return res.status(400).json({ error: '缺少 data 参数' });
|
||
}
|
||
|
||
// 解码 data（支持 URL 编码的换行符）
|
||
params.data = params.data.replace(/\\n/g, '\n');
|
||
|
||
const option = buildChartOption(params);
|
||
|
||
const width = params.width;
|
||
const height = params.height;
|
||
const pixelRatio = params.pixelRatio;
|
||
|
||
const canvas = createCanvas(width * pixelRatio, height * pixelRatio);
|
||
const chart = echarts.init(canvas, null, {
|
||
renderer: 'canvas',
|
||
width: width,
|
||
height: height,
|
||
devicePixelRatio: pixelRatio
|
||
});
|
||
|
||
chart.setOption(option);
|
||
|
||
const buffer = canvas.toBuffer('image/png');
|
||
res.set({
|
||
'Content-Type': 'image/png',
|
||
'Content-Length': buffer.length,
|
||
'X-Chart-Width': width,
|
||
'X-Chart-Height': height
|
||
});
|
||
res.send(buffer);
|
||
|
||
chart.dispose();
|
||
} catch (err) {
|
||
console.error('Chart generation error:', err);
|
||
res.status(500).json({ error: '图表生成失败: ' + err.message });
|
||
}
|
||
});
|
||
|
||
// ===== API: 健康检查 =====
|
||
app.get('/api/health', (req, res) => {
|
||
res.json({
|
||
status: 'ok',
|
||
service: 'data-chart-tool',
|
||
version: '1.1.0',
|
||
endpoints: {
|
||
'POST /api/chart': '生成图表图片（JSON body）',
|
||
'GET /api/chart': '生成图表图片（URL 参数）',
|
||
'GET /api/health': '健康检查'
|
||
}
|
||
});
|
||
});
|
||
|
||
// ===== API: 文档/使用说明 =====
|
||
app.get('/api/docs', (req, res) => {
|
||
res.json({
|
||
name: '数据可视化图表生成器 API',
|
||
version: '1.1.0',
|
||
endpoints: [
|
||
{
|
||
method: 'POST',
|
||
path: '/api/chart',
|
||
description: '通过 JSON 请求体生成图表图片',
|
||
'Content-Type': 'application/json',
|
||
params: {
|
||
data: { type: 'string', required: true, description: 'CSV 格式数据（第一行表头，第一列横坐标）' },
|
||
chartType: { type: 'string', default: 'bar', options: ['bar', 'line', 'bar-line'], description: '图表类型' },
|
||
title: { type: 'string', default: '', description: '图表标题' },
|
||
theme: { type: 'string', default: 'default', options: ['default', 'dark', 'macarons', 'gradient', 'retro'], description: '主题风格' },
|
||
showLegend: { type: 'boolean', default: true, description: '是否显示图例' },
|
||
showGrid: { type: 'boolean', default: true, description: '是否显示网格线' },
|
||
showLabel: { type: 'boolean', default: false, description: '是否显示数据标签' },
|
||
stackMode: { type: 'boolean', default: false, description: '是否堆叠模式' },
|
||
smoothLine: { type: 'boolean', default: true, description: '折线图是否平滑' },
|
||
enableSplit: { type: 'boolean', default: false, description: '是否启用区域分割' },
|
||
splitIndex: { type: 'number', default: 3, description: '分割位置索引' },
|
||
leftLabel: { type: 'string', default: '左侧', description: '左侧区域标签' },
|
||
rightLabel: { type: 'string', default: '右侧', description: '右侧区域标签' },
|
||
splitStyle: { type: 'string', default: 'solid', options: ['solid', 'dashed', 'dotted'], description: '分割线样式' },
|
||
width: { type: 'number', default: 800, description: '图片宽度(px)' },
|
||
height: { type: 'number', default: 500, description: '图片高度(px)' },
|
||
format: { type: 'string', default: 'png', options: ['png'], description: '输出格式' },
|
||
pixelRatio: { type: 'number', default: 2, description: '像素倍率（清晰度）' }
|
||
},
|
||
returns: 'image/png',
|
||
example: {
|
||
request: `curl -X POST http://localhost:16016/api/chart \\
|
||
-H "Content-Type: application/json" \\
|
||
-d '{
|
||
"data": "产品, Q1, Q2, Q3, Q4\\n手机, 1200, 1800, 2100, 2500\\n平板, 800, 950, 1100, 1300",
|
||
"chartType": "bar",
|
||
"title": "季度销售对比",
|
||
"theme": "default",
|
||
"width": 800,
|
||
"height": 500
|
||
}' -o chart.png`,
|
||
response: 'PNG 图片二进制流'
|
||
}
|
||
},
|
||
{
|
||
method: 'GET',
|
||
path: '/api/chart',
|
||
description: '通过 URL 参数生成图表图片（适合简单场景）',
|
||
params: {
|
||
data: { type: 'string', required: true, description: 'CSV 数据（换行用 \\n 分隔）' },
|
||
type: { type: 'string', default: 'bar', description: '图表类型' },
|
||
title: { type: 'string', description: '图表标题' },
|
||
theme: { type: 'string', default: 'default', description: '主题风格' },
|
||
width: { type: 'number', default: 800 },
|
||
height: { type: 'number', default: 500 }
|
||
},
|
||
returns: 'image/png',
|
||
example: {
|
||
request: `curl "http://localhost:16016/api/chart?data=产品,Q1,Q2\\n手机,100,200\\n平板,150,250&type=bar&title=测试" -o chart.png`
|
||
}
|
||
}
|
||
]
|
||
});
|
||
});
|
||
|
||
// ===== 启动服务 =====
|
||
app.listen(PORT, '0.0.0.0', () => {
|
||
console.log(`🚀 数据可视化图表生成器已启动`);
|
||
console.log(`📊 Web UI: http://0.0.0.0:${PORT}`);
|
||
console.log(`📡 API: http://0.0.0.0:${PORT}/api/chart`);
|
||
console.log(`📖 文档: http://0.0.0.0:${PORT}/api/docs`);
|
||
console.log(`❤️ 健康: http://0.0.0.0:${PORT}/api/health`);
|
||
});
|