hz4th_coder
6a696daeb8
- 图表模式新增双Y轴：左右两个坐标轴，量度可不同 - 显示选项加"双Y轴"开关，启用后显示右轴名称输入 - 每个系列在系列配置中可选择左轴/右轴 - 后端 /api/chart 支持 dualYAxis + rightAxisSeries + rightAxisName（POST/GET 均可） - 导出设置折叠栏下载按钮改小，避免挤占
1166 lines
43 KiB
JavaScript
1166 lines
43 KiB
JavaScript
const express = require('express');
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const cors = require('cors');
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const { createCanvas, registerFont, loadImage } = require('@napi-rs/canvas');
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const echarts = require('echarts');
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const path = require('path');
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// 注册中文字体
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try {
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const { GlobalFonts } = require('@napi-rs/canvas');
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GlobalFonts.registerFromPath('/usr/share/fonts/opentype/noto/NotoSansCJK-Regular.ttc', 'Noto Sans CJK SC');
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GlobalFonts.registerFromPath('/usr/share/fonts/opentype/noto/NotoSansCJK-Bold.ttc', 'Noto Sans CJK SC');
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console.log('中文字体注册成功');
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} catch (e) {
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console.warn('中文字体注册失败，将使用系统默认字体:', e.message);
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}
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const app = express();
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const PORT = process.env.PORT || 16016;
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// 中间件
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app.use(cors());
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app.use(express.json({ limit: '10mb' }));
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app.use(express.urlencoded({ extended: true, limit: '10mb' }));
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// 静态文件（前端页面）
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app.use(express.static(path.join(__dirname)));
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// ===== 预设颜色方案 =====
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const colorPalettes = {
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default: ['#5470c6', '#91cc75', '#fac858', '#ee6666', '#73c0de', '#3ba272', '#fc8452', '#9a60b4', '#ea7ccc'],
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dark: ['#4fc3f7', '#81c784', '#fff176', '#ff8a65', '#ba68c8', '#4dd0e1', '#ffab91', '#aed581', '#f48fb1'],
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macarons: ['#2ec7c9', '#b6a2de', '#5ab1ef', '#ffb980', '#d87a80', '#8d98b3', '#e5cf0d', '#97b552', '#95706d'],
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gradient: ['#7f7fd5', '#86a8e7', '#91eae4', '#ff6b6b', '#feca57', '#48dbfb', '#ff9ff3', '#54a0ff', '#5f27cd'],
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retro: ['#d4a5a5', '#95b9c7', '#f6e8c3', '#dfceb4', '#a4c3b5', '#c9b1ff', '#f5c7b8', '#b8d4e3', '#e8c8a0'],
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ocean: ['#0077b6', '#00b4d8', '#90e0ef', '#caf0f8', '#023e8a', '#48cae4', '#ade8f4', '#0096c7', '#03045e'],
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forest: ['#2d6a4f', '#40916c', '#52b788', '#74c69d', '#95d5b2', '#b7e4c7', '#d8f3dc', '#1b4332', '#344e41'],
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sunset: ['#e85d04', '#f48c06', '#faa307', '#ffba08', '#dc2f02', '#d00000', '#9d0208', '#6a040f', '#370617'],
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lavender: ['#7c3aed', '#8b5cf6', '#a78bfa', '#c4b5fd', '#ddd6fe', '#ede9fe', '#5b21b6', '#4c1d95', '#6d28d9'],
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minimal: ['#111827', '#374151', '#6b7280', '#9ca3af', '#d1d5db', '#e5e7eb', '#f3f4f6', '#4b5563', '#1f2937'],
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cherry: ['#e91e63', '#f06292', '#f48fb1', '#f8bbd0', '#fce4ec', '#c2185b', '#ad1457', '#880e4f', '#d81b60'],
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midnight: ['#6c63ff', '#5a52d5', '#483fb5', '#7c79ff', '#3d3d5c', '#8b89ff', '#9d9bff', '#2c2c4a', '#b3b2ff'],
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gold: ['#b8860b', '#daa520', '#f0c040', '#ffd700', '#ffe066', '#996515', '#cc9900', '#e6b800', '#8b6914'],
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coral: ['#ff6f61', '#ff8a70', '#ffa07a', '#ffab91', '#ffccbc', '#e64a19', '#f4511e', '#ff5722', '#d84315'],
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mint: ['#00bfa5', '#26a69a', '#4db6ac', '#80cbc4', '#b2dfdb', '#00897b', '#00796b', '#004d40', '#009688']
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};
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// ===== 数据解析（与前端一致） =====
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function parseData(rawText) {
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const lines = rawText.trim().split('\n').filter(l => l.trim());
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if (lines.length < 2) {
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throw new Error('数据至少需要包含表头和一行数据');
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}
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// 自动检测分隔符
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let delimiter = ',';
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if (lines[0].includes('\t')) {
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delimiter = '\t';
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} else if (lines[0].split('|').length > lines[0].split(',').length) {
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delimiter = '|';
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}
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const rows = lines.map(line => {
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return line.split(delimiter).map(cell => cell.trim());
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});
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const headers = rows[0];
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const categories = [];
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const seriesData = {};
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for (let i = 1; i < headers.length; i++) {
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seriesData[headers[i]] = [];
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}
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for (let i = 1; i < rows.length; i++) {
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categories.push(rows[i][0]);
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for (let j = 1; j < rows[i].length && j < headers.length; j++) {
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const val = parseFloat(rows[i][j]);
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seriesData[headers[j]].push(isNaN(val) ? 0 : val);
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}
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}
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return {
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categories,
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seriesNames: headers.slice(1),
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seriesData
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};
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}
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// ===== 颜色工具 =====
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function adjustColor(hex, amount) {
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hex = hex.replace('#', '');
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const num = parseInt(hex, 16);
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let r = Math.min(255, ((num >> 16) & 0xff) + amount);
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let g = Math.min(255, ((num >> 8) & 0xff) + amount);
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let b = Math.min(255, (num & 0xff) + amount);
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return `rgb(${r},${g},${b})`;
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}
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// ===== 构建 ECharts option =====
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function buildChartOption(params) {
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const {
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data,
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chartType = 'bar',
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title = '',
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theme = 'default',
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showLegend = true,
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showGrid = true,
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showLabel = false,
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stackMode = false,
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smoothLine = true,
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enableSplit = false,
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splitIndex = 3,
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leftLabel = '左侧',
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rightLabel = '右侧',
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splitStyle = 'solid',
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seriesColors: customColors = null,
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dualYAxis = false,
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rightAxisSeries = null,
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rightAxisName = ''
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} = params;
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const parsedData = parseData(data);
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const palette = colorPalettes[theme] || colorPalettes.default;
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const seriesColorsArr = customColors || parsedData.seriesNames.map((_, i) => palette[i % palette.length]);
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// 背景色和文字色
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const bgColor = theme === 'dark' ? '#1a1a2e' : '#ffffff';
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const textColor = theme === 'dark' ? '#e0e0e0' : '#333333';
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const axisLineColor = theme === 'dark' ? '#444' : '#ddd';
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// 构建系列
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const series = parsedData.seriesNames.map((name, idx) => {
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const dataArr = parsedData.seriesData[name];
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const color = seriesColorsArr[idx] || palette[idx % palette.length];
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let type = chartType === 'bar-line'
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? (idx % 2 === 0 ? 'bar' : 'line')
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: chartType;
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const seriesItem = {
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name: name,
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type: type,
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data: [...dataArr],
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itemStyle: { color: color },
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emphasis: {
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focus: 'series',
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itemStyle: {
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shadowBlur: 10,
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shadowColor: 'rgba(0,0,0,0.3)'
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}
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}
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};
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// 双Y轴：rightAxisSeries 指定右轴系列名
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if (dualYAxis) {
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const rightNames = Array.isArray(rightAxisSeries) ? rightAxisSeries : (rightAxisSeries ? [rightAxisSeries] : []);
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seriesItem.yAxisIndex = rightNames.includes(name) ? 1 : 0;
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}
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if (stackMode) {
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seriesItem.stack = 'total';
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}
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if (type === 'line') {
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seriesItem.smooth = smoothLine;
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seriesItem.lineStyle = { width: 3 };
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seriesItem.symbolSize = 8;
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seriesItem.areaStyle = theme === 'gradient' ? { opacity: 0.15 } : undefined;
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}
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if (type === 'bar') {seriesItem.barMaxWidth = 40;
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seriesItem.itemStyle.borderRadius = stackMode ? [0, 0, 0, 0] : [4, 4, 0, 0];
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}
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if (showLabel) {
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seriesItem.label = {
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show: true,
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position: 'top',
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fontSize: 11,
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color: textColor,
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formatter: (p) => {
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if (p.value >= 10000) return (p.value / 10000).toFixed(1) + 'w';
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if (p.value >= 1000) return (p.value / 1000).toFixed(1) + 'k';
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return p.value;
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}
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};
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}
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return seriesItem;
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});
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// 区域分割
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if (enableSplit && splitIndex < parsedData.categories.length && series.length > 0) {
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const splitLineColor = theme === 'dark' ? '#ff6b6b' : '#e74c3c';
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series[0].markArea = {
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silent: true,
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data: [
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[
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{
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name: leftLabel,
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xAxis: parsedData.categories[0],
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itemStyle: {
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color: theme === 'dark' ? 'rgba(79,195,247,0.06)' : 'rgba(79,70,229,0.05)',
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borderWidth: 0
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},
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label: {
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show: true,
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position: 'insideTop',
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fontSize: 13,
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fontWeight: 'bold',
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color: theme === 'dark' ? '#4fc3f7' : '#4f46e5',
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offset: [0, 10]
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}
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},
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{ xAxis: parsedData.categories[splitIndex - 1] }
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],
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[
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{
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name: rightLabel,
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xAxis: parsedData.categories[splitIndex],
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itemStyle: {
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color: theme === 'dark' ? 'rgba(255,107,107,0.06)' : 'rgba(239,68,68,0.05)',
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borderWidth: 0
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},
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label: {
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show: true,
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position: 'insideTop',
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fontSize: 13,
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fontWeight: 'bold',
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color: theme === 'dark' ? '#ff6b6b' : '#ef4444',
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offset: [0, 10]
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}
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},
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{ xAxis: parsedData.categories[parsedData.categories.length - 1] }
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]
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]
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};
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}
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// 完整 option
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const option = {
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backgroundColor: bgColor,
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title: title ? {
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text: title,
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left: 'center',
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top: 15,
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textStyle: {
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color: textColor,
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fontSize: 18,
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fontWeight: 600
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}
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} : undefined,
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tooltip: { show: false },
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legend: showLegend ? {
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show: true,
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top: title ? 50 : 15,
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textStyle: { color: textColor, fontSize: 12 },
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itemGap: 20,
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icon: 'roundRect'
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} : { show: false },
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grid: {
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left: '3%',
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right: '4%',
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bottom: '3%',
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top: showLegend ? (title ? 90 : 60) : (title ? 60 : 30),
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containLabel: true
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},
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xAxis: {
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type: 'category',
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data: parsedData.categories,
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axisLine: { lineStyle: { color: axisLineColor } },
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axisLabel: {
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color: textColor,
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fontSize: 12,
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interval: 0,
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rotate: parsedData.categories.length > 10 ? 30 : 0
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},
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axisTick: { show: false }
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},
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yAxis: dualYAxis ? [
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{
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type: 'value',
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name: '左轴',
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nameTextStyle: { color: textColor, fontSize: 11, padding: [0, 0, 0, 4] },
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axisLine: { show: false },
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axisTick: { show: false },
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axisLabel: { color: textColor, fontSize: 11 },
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splitLine: {
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show: showGrid,
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lineStyle: {
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color: theme === 'dark' ? '#333' : '#f0f0f0',
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type: 'dashed'
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}
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}
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},
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{
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type: 'value',
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name: rightAxisName || '右轴',
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position: 'right',
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nameTextStyle: { color: textColor, fontSize: 11, padding: [0, 4, 0, 0] },
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axisLine: { show: false },
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axisTick: { show: false },
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axisLabel: { color: textColor, fontSize: 11 },
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splitLine: { show: false }
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}
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] : {
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type: 'value',
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axisLine: { show: false },
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axisTick: { show: false },
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axisLabel: { color: textColor, fontSize: 11 },
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splitLine: {
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show: showGrid,
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lineStyle: {
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color: theme === 'dark' ? '#333' : '#f0f0f0',
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type: 'dashed'
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}
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}
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},
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series: series,
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animation: false // 服务端渲染关闭动画
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};
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return option;
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}
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// ===== API: 生成图表图片 =====
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app.post('/api/chart', (req, res) => {
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try {
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const params = req.body;
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if (!params.data) {
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return res.status(400).json({ error: '缺少 data 参数（CSV 格式数据）' });
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}
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const width = parseInt(params.width) || 800;
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const height = parseInt(params.height) || 500;
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const format = params.format || 'png';
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const pixelRatio = parseInt(params.pixelRatio) || 2;
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// 构建图表配置
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const option = buildChartOption(params);
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// 创建 canvas 并渲染
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const canvas = createCanvas(width * pixelRatio, height * pixelRatio);
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const chart = echarts.init(canvas, null, {
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renderer: 'canvas',
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width: width,
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height: height,
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devicePixelRatio: pixelRatio
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});
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chart.setOption(option);
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// 输出图片
|
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if (format === 'svg') {
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// SVG 需要用 SVG 渲染器重新渲染
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// node-canvas 不支持 SVG，返回 PNG 并提示
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const buffer = canvas.toBuffer('image/png');
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res.set({
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'Content-Type': 'image/png',
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'Content-Length': buffer.length,
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'X-Chart-Format': 'png',
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'X-Chart-Note': 'SVG format not supported in server-side rendering, returned PNG instead'
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});
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res.send(buffer);
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} else {
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const buffer = canvas.toBuffer('image/png');
|
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res.set({
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'Content-Type': 'image/png',
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'Content-Length': buffer.length,
|
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'X-Chart-Width': width,
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'X-Chart-Height': height,
|
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'X-Chart-Pixel-Ratio': pixelRatio
|
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});
|
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res.send(buffer);
|
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}
|
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|
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chart.dispose();
|
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} 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 {
|
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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',
|
||
dualYAxis: req.query.dualYAxis === 'true',
|
||
rightAxisSeries: req.query.rightAxisSeries ? req.query.rightAxisSeries.split(',') : null,
|
||
rightAxisName: req.query.rightAxisName || '',
|
||
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 });
|
||
}
|
||
});
|
||
|
||
// ===== 表格数据解析（保留原始文本） =====
|
||
function parseTableData(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());
|
||
});
|
||
|
||
return {
|
||
headers: rows[0],
|
||
rows: rows.slice(1)
|
||
};
|
||
}
|
||
|
||
// ===== 表格主题配置 =====
|
||
const tableThemes = {
|
||
default: {
|
||
bgColor: '#ffffff',
|
||
headerBg: '#5470c6',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#333333',
|
||
borderColor: '#e0e0e0',
|
||
stripeColor: '#f8f9fa',
|
||
titleColor: '#333333'
|
||
},
|
||
dark: {
|
||
bgColor: '#1a1a2e',
|
||
headerBg: '#4fc3f7',
|
||
headerColor: '#1a1a2e',
|
||
cellColor: '#e0e0e0',
|
||
borderColor: '#444444',
|
||
stripeColor: '#252540',
|
||
titleColor: '#e0e0e0'
|
||
},
|
||
macarons: {
|
||
bgColor: '#ffffff',
|
||
headerBg: '#2ec7c9',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#333333',
|
||
borderColor: '#e8e8e8',
|
||
stripeColor: '#f0fafb',
|
||
titleColor: '#333333'
|
||
},
|
||
gradient: {
|
||
bgColor: '#ffffff',
|
||
headerBg: '#7f7fd5',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#333333',
|
||
borderColor: '#e8e8e8',
|
||
stripeColor: '#f5f5ff',
|
||
titleColor: '#333333'
|
||
},
|
||
retro: {
|
||
bgColor: '#fefefe',
|
||
headerBg: '#95b9c7',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#444444',
|
||
borderColor: '#d4a5a5',
|
||
stripeColor: '#f6e8c3',
|
||
titleColor: '#444444'
|
||
},
|
||
ocean: {
|
||
bgColor: '#f0f8ff',
|
||
headerBg: '#0077b6',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#023e58',
|
||
borderColor: '#90e0ef',
|
||
stripeColor: '#caf0f8',
|
||
titleColor: '#023e58'
|
||
},
|
||
forest: {
|
||
bgColor: '#f5faf5',
|
||
headerBg: '#2d6a4f',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#1b4332',
|
||
borderColor: '#95d5b2',
|
||
stripeColor: '#d8f3dc',
|
||
titleColor: '#1b4332'
|
||
},
|
||
sunset: {
|
||
bgColor: '#fff8f0',
|
||
headerBg: '#e85d04',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#6a040f',
|
||
borderColor: '#ffba08',
|
||
stripeColor: '#fff3e0',
|
||
titleColor: '#6a040f'
|
||
},
|
||
lavender: {
|
||
bgColor: '#faf5ff',
|
||
headerBg: '#7c3aed',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#4c1d95',
|
||
borderColor: '#c4b5fd',
|
||
stripeColor: '#ede9fe',
|
||
titleColor: '#4c1d95'
|
||
},
|
||
minimal: {
|
||
bgColor: '#ffffff',
|
||
headerBg: '#f8f9fa',
|
||
headerColor: '#212529',
|
||
cellColor: '#495057',
|
||
borderColor: '#dee2e6',
|
||
stripeColor: '#f8f9fa',
|
||
titleColor: '#212529'
|
||
},
|
||
cherry: {
|
||
bgColor: '#fff5f7',
|
||
headerBg: '#e91e63',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#880e4f',
|
||
borderColor: '#f48fb1',
|
||
stripeColor: '#fce4ec',
|
||
titleColor: '#880e4f'
|
||
},
|
||
midnight: {
|
||
bgColor: '#1a1a2e',
|
||
headerBg: '#6c63ff',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#e0e0e0',
|
||
borderColor: '#3d3d5c',
|
||
stripeColor: '#22223a',
|
||
titleColor: '#e0e0e0'
|
||
},
|
||
gold: {
|
||
bgColor: '#fffef5',
|
||
headerBg: '#b8860b',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#5c4a00',
|
||
borderColor: '#daa520',
|
||
stripeColor: '#fdf6e3',
|
||
titleColor: '#5c4a00'
|
||
},
|
||
coral: {
|
||
bgColor: '#fff5f2',
|
||
headerBg: '#ff6f61',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#5d2b1f',
|
||
borderColor: '#ffab91',
|
||
stripeColor: '#fff0ed',
|
||
titleColor: '#5d2b1f'
|
||
},
|
||
mint: {
|
||
bgColor: '#f0fff8',
|
||
headerBg: '#00bfa5',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#004d40',
|
||
borderColor: '#80cbc4',
|
||
stripeColor: '#e0f2f1',
|
||
titleColor: '#004d40'
|
||
},
|
||
// 简约纯色风格
|
||
slate: {
|
||
bgColor: '#ffffff',
|
||
headerBg: '#475569',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#334155',
|
||
borderColor: '#cbd5e1',
|
||
stripeColor: '#f8fafc',
|
||
titleColor: '#1e293b'
|
||
},
|
||
sky: {
|
||
bgColor: '#ffffff',
|
||
headerBg: '#0ea5e9',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#0c4a6e',
|
||
borderColor: '#bae6fd',
|
||
stripeColor: '#f0f9ff',
|
||
titleColor: '#0c4a6e'
|
||
},
|
||
rose: {
|
||
bgColor: '#ffffff',
|
||
headerBg: '#e11d48',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#881337',
|
||
borderColor: '#fecdd3',
|
||
stripeColor: '#fff1f2',
|
||
titleColor: '#881337'
|
||
},
|
||
amber: {
|
||
bgColor: '#ffffff',
|
||
headerBg: '#f59e0b',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#78350f',
|
||
borderColor: '#fde68a',
|
||
stripeColor: '#fffbeb',
|
||
titleColor: '#78350f'
|
||
},
|
||
emerald: {
|
||
bgColor: '#ffffff',
|
||
headerBg: '#10b981',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#064e3b',
|
||
borderColor: '#a7f3d0',
|
||
stripeColor: '#ecfdf5',
|
||
titleColor: '#064e3b'
|
||
},
|
||
indigo: {
|
||
bgColor: '#ffffff',
|
||
headerBg: '#6366f1',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#312e81',
|
||
borderColor: '#c7d2fe',
|
||
stripeColor: '#eef2ff',
|
||
titleColor: '#312e81'
|
||
},
|
||
stone: {
|
||
bgColor: '#ffffff',
|
||
headerBg: '#78716c',
|
||
headerColor: '#ffffff',
|
||
cellColor: '#44403c',
|
||
borderColor: '#d6d3d1',
|
||
stripeColor: '#fafaf9',
|
||
titleColor: '#292524'
|
||
}
|
||
};
|
||
|
||
// ===== 测量文字宽度 =====
|
||
function measureTextWidth(ctx, text, fontSize) {
|
||
ctx.font = `${fontSize}px "Noto Sans CJK SC", sans-serif`;
|
||
const metrics = ctx.measureText(text);
|
||
return metrics.width;
|
||
}
|
||
|
||
// ===== 生成表格图片 =====
|
||
function generateTableImage(params) {
|
||
const {
|
||
data,
|
||
title = '',
|
||
theme = 'default',
|
||
fontSize = 14,
|
||
cellPadding = 12,
|
||
borderWidth = 1,
|
||
stripeRows = true,
|
||
pixelRatio = 2,
|
||
maxWidth = 1200,
|
||
borderStyle = 'all' // all, none, no-outer, no-horizontal, no-vertical, no-inner, no-inner-horizontal, no-inner-vertical, outer-only, header-only
|
||
} = params;
|
||
|
||
const tableData = parseTableData(data);
|
||
const { headers, rows } = tableData;
|
||
const themeConfig = tableThemes[theme] || tableThemes.default;
|
||
|
||
// 创建临时 canvas 用于测量文字
|
||
const tempCanvas = createCanvas(100, 100);
|
||
const tempCtx = tempCanvas.getContext('2d');
|
||
|
||
// 计算每列最大宽度
|
||
const colWidths = headers.map((header, colIdx) => {
|
||
let maxW = measureTextWidth(tempCtx, header, fontSize) + cellPadding * 2;
|
||
|
||
rows.forEach(row => {
|
||
if (row[colIdx]) {
|
||
const cellW = measureTextWidth(tempCtx, row[colIdx], fontSize) + cellPadding * 2;
|
||
if (cellW > maxW) maxW = cellW;
|
||
}
|
||
});
|
||
|
||
return Math.min(maxW, 300); // 单列最大宽度 300px
|
||
});
|
||
|
||
// 计算表格总宽度
|
||
const tableWidth = colWidths.reduce((sum, w) => sum + w, 0) + borderWidth * 2;
|
||
const finalWidth = Math.min(tableWidth, maxWidth);
|
||
|
||
// 如果超出最大宽度，按比例缩放列宽
|
||
if (tableWidth > maxWidth) {
|
||
const scale = maxWidth / tableWidth;
|
||
colWidths.forEach((_, i) => colWidths[i] *= scale);
|
||
}
|
||
|
||
// 计算行高
|
||
const headerHeight = fontSize * 2.5;
|
||
const rowHeight = fontSize * 2.2;
|
||
const titleHeight = title ? fontSize * 3 : 0;
|
||
const tableHeight = headerHeight + rows.length * rowHeight;
|
||
const finalHeight = tableHeight + titleHeight;
|
||
|
||
// 创建正式 canvas
|
||
const canvas = createCanvas(finalWidth * pixelRatio, finalHeight * pixelRatio);
|
||
const ctx = canvas.getContext('2d');
|
||
ctx.scale(pixelRatio, pixelRatio);
|
||
|
||
// 绘制背景
|
||
ctx.fillStyle = themeConfig.bgColor;
|
||
ctx.fillRect(0, 0, finalWidth, finalHeight);
|
||
|
||
let startY = 0;
|
||
|
||
// 绘制标题
|
||
if (title) {
|
||
ctx.fillStyle = themeConfig.titleColor;
|
||
ctx.font = `bold ${fontSize * 1.4}px "Noto Sans CJK SC", sans-serif`;
|
||
ctx.textAlign = 'center';
|
||
ctx.textBaseline = 'middle';
|
||
ctx.fillText(title, finalWidth / 2, titleHeight / 2);
|
||
startY = titleHeight;
|
||
}
|
||
|
||
// 绘制表头背景
|
||
ctx.fillStyle = themeConfig.headerBg;
|
||
ctx.fillRect(0, startY, finalWidth, headerHeight);
|
||
|
||
// 绘制表头文字
|
||
ctx.fillStyle = themeConfig.headerColor;
|
||
ctx.font = `bold ${fontSize}px "Noto Sans CJK SC", sans-serif`;
|
||
ctx.textAlign = 'left';
|
||
ctx.textBaseline = 'middle';
|
||
|
||
let x = 0;
|
||
headers.forEach((header, i) => {
|
||
ctx.fillText(header, x + cellPadding, startY + headerHeight / 2, colWidths[i] - cellPadding * 2);
|
||
x += colWidths[i];
|
||
});
|
||
|
||
// 绘制数据行
|
||
rows.forEach((row, rowIdx) => {
|
||
const y = startY + headerHeight + rowIdx * rowHeight;
|
||
|
||
// 斑马纹背景
|
||
if (stripeRows && rowIdx % 2 === 1) {
|
||
ctx.fillStyle = themeConfig.stripeColor;
|
||
ctx.fillRect(0, y, finalWidth, rowHeight);
|
||
}
|
||
|
||
// 绘制单元格文字
|
||
ctx.fillStyle = themeConfig.cellColor;
|
||
ctx.font = `${fontSize}px "Noto Sans CJK SC", sans-serif`;
|
||
ctx.textAlign = 'left';
|
||
ctx.textBaseline = 'middle';
|
||
|
||
let cellX = 0;
|
||
row.forEach((cell, colIdx) => {
|
||
if (cell && colWidths[colIdx]) {
|
||
ctx.fillText(cell, cellX + cellPadding, y + rowHeight / 2, colWidths[colIdx] - cellPadding * 2);
|
||
}
|
||
cellX += colWidths[colIdx];
|
||
});
|
||
});
|
||
|
||
// 绘制边框
|
||
ctx.strokeStyle = themeConfig.borderColor;
|
||
ctx.lineWidth = borderWidth;
|
||
|
||
// 边框样式控制
|
||
const drawOuter = !['none', 'no-outer', 'no-inner', 'no-inner-horizontal', 'no-inner-vertical', 'header-only'].includes(borderStyle);
|
||
const drawHorizontal = !['none', 'no-horizontal', 'no-inner', 'no-inner-horizontal', 'outer-only', 'header-only'].includes(borderStyle);
|
||
const drawVertical = !['none', 'no-vertical', 'no-inner', 'no-inner-vertical', 'outer-only'].includes(borderStyle);
|
||
const drawHeaderLine = !['none', 'no-horizontal', 'no-inner', 'no-inner-horizontal'].includes(borderStyle);
|
||
|
||
// 外边框
|
||
if (drawOuter) {
|
||
const offset = borderWidth / 2;
|
||
ctx.strokeRect(offset, startY + offset, finalWidth - borderWidth, tableHeight - borderWidth);
|
||
}
|
||
|
||
// 表头分隔线（横线）
|
||
if (drawHeaderLine) {
|
||
ctx.beginPath();
|
||
ctx.moveTo(0, startY + headerHeight);
|
||
ctx.lineTo(finalWidth, startY + headerHeight);
|
||
ctx.stroke();
|
||
}
|
||
|
||
// 数据行横线
|
||
if (drawHorizontal) {
|
||
rows.forEach((_, rowIdx) => {
|
||
const y = startY + headerHeight + (rowIdx + 1) * rowHeight;
|
||
ctx.beginPath();
|
||
ctx.moveTo(0, y);
|
||
ctx.lineTo(finalWidth, y);
|
||
ctx.stroke();
|
||
});
|
||
}
|
||
|
||
// 竖线
|
||
if (drawVertical) {
|
||
x = 0;
|
||
colWidths.forEach((width, i) => {
|
||
if (i > 0) {
|
||
ctx.beginPath();
|
||
ctx.moveTo(x, startY);
|
||
ctx.lineTo(x, startY + tableHeight);
|
||
ctx.stroke();
|
||
}
|
||
x += width;
|
||
});
|
||
}
|
||
|
||
return canvas;
|
||
}
|
||
|
||
// ===== API: 生成表格图片 (POST) =====
|
||
app.post('/api/table', (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 pixelRatio = parseInt(params.pixelRatio) || 2;
|
||
const canvas = generateTableImage(params);
|
||
|
||
const buffer = canvas.toBuffer('image/png');
|
||
res.set({
|
||
'Content-Type': 'image/png',
|
||
'Content-Length': buffer.length,
|
||
'X-Table-Format': 'png'
|
||
});
|
||
res.send(buffer);
|
||
} catch (err) {
|
||
console.error('Table generation error:', err);
|
||
res.status(500).json({ error: '表格生成失败: ' + err.message });
|
||
}
|
||
});
|
||
|
||
// ===== API: 生成表格图片 (GET) =====
|
||
app.get('/api/table', (req, res) => {
|
||
try {
|
||
const params = {
|
||
data: req.query.data,
|
||
title: req.query.title || '',
|
||
theme: req.query.theme || 'default',
|
||
fontSize: parseInt(req.query.fontSize) || 14,
|
||
cellPadding: parseInt(req.query.cellPadding) || 12,
|
||
borderWidth: parseInt(req.query.borderWidth) || 1,
|
||
stripeRows: req.query.stripeRows !== 'false',
|
||
pixelRatio: parseInt(req.query.pixelRatio) || 2,
|
||
maxWidth: parseInt(req.query.maxWidth) || 1200,
|
||
borderStyle: req.query.borderStyle || 'all'
|
||
};
|
||
|
||
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 canvas = generateTableImage(params);
|
||
const buffer = canvas.toBuffer('image/png');
|
||
|
||
res.set({
|
||
'Content-Type': 'image/png',
|
||
'Content-Length': buffer.length,
|
||
'X-Table-Format': 'png'
|
||
});
|
||
res.send(buffer);
|
||
} catch (err) {
|
||
console.error('Table generation error:', err);
|
||
res.status(500).json({ error: '表格生成失败: ' + err.message });
|
||
}
|
||
});
|
||
|
||
// ===== API: 健康检查 =====
|
||
app.get('/api/health', (req, res) => {
|
||
res.json({
|
||
status: 'ok',
|
||
service: 'data-chart-tool',
|
||
version: '1.11.0',
|
||
endpoints: {
|
||
'POST /api/chart': '生成图表图片（JSON body）',
|
||
'GET /api/chart': '生成图表图片（URL 参数）',
|
||
'POST /api/table': '生成表格图片（JSON body）',
|
||
'GET /api/table': '生成表格图片（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: '1.11.0',
|
||
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', 'ocean', 'forest', 'sunset', 'lavender', 'minimal', 'cherry', 'midnight', 'gold', 'coral', 'mint'], 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）' },
|
||
dualYAxis: { type: 'boolean', default: false, description: '是否启用双Y轴（左右量度不同）' },
|
||
rightAxisSeries: { type: 'array', default: null, description: '右轴系列名列表（如 ["利润"]，指定哪些系列用右轴）' },
|
||
rightAxisName: { type: 'string', default: '', description: '右轴名称' }
|
||
},
|
||
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`
|
||
}
|
||
},
|
||
{
|
||
method: 'POST',
|
||
path: '/api/table',
|
||
description: '通过 JSON 请求体生成表格图片',
|
||
'Content-Type': 'application/json',
|
||
params: {
|
||
data: { type: 'string', required: true, description: 'CSV 格式数据（第一行表头）' },
|
||
title: { type: 'string', default: '', description: '表格标题' },
|
||
theme: { type: 'string', default: 'default', options: ['default', 'dark', 'macarons', 'gradient', 'retro', 'ocean', 'forest', 'sunset', 'lavender', 'minimal', 'cherry', 'midnight', 'gold', 'coral', 'mint'], description: '主题风格' },
|
||
fontSize: { type: 'number', default: 14, description: '字体大小' },
|
||
cellPadding: { type: 'number', default: 12, description: '单元格内边距' },
|
||
borderWidth: { type: 'number', default: 1, description: '边框宽度' },
|
||
stripeRows: { type: 'boolean', default: true, description: '是否斑马纹' },
|
||
pixelRatio: { type: 'number', default: 2, description: '像素倍率（清晰度）' },
|
||
maxWidth: { type: 'number', default: 1200, description: '最大宽度(px)' },
|
||
borderStyle: { type: 'string', default: 'all', options: ['all', 'none', 'no-outer', 'no-horizontal', 'no-vertical', 'no-inner', 'no-inner-horizontal', 'no-inner-vertical', 'outer-only', 'header-only'], description: '边框样式' }
|
||
},
|
||
returns: 'image/png',
|
||
example: {
|
||
request: `curl -X POST http://localhost:16016/api/table \\
|
||
-H "Content-Type: application/json" \\
|
||
-d '{
|
||
"data": "姓名, 部门, 职位, 薪资\\n张三, 技术部, 工程师, 15000\\n李四, 产品部, 产品经理, 18000\\n王五, 设计部, UI设计师, 16000",
|
||
"title": "员工信息表",
|
||
"theme": "default"
|
||
}' -o table.png`,
|
||
response: 'PNG 图片二进制流'
|
||
}
|
||
},
|
||
{
|
||
method: 'GET',
|
||
path: '/api/table',
|
||
description: '通过 URL 参数生成表格图片',
|
||
params: {
|
||
data: { type: 'string', required: true, description: 'CSV 数据（换行用 \\n 分隔）' },
|
||
title: { type: 'string', description: '表格标题' },
|
||
theme: { type: 'string', default: 'default', description: '主题风格' },
|
||
fontSize: { type: 'number', default: 14 },
|
||
stripeRows: { type: 'boolean', default: true }
|
||
},
|
||
returns: 'image/png',
|
||
example: {
|
||
request: `curl "http://localhost:16016/api/table?data=产品,价格,库存\\n手机,2999,100\\n平板,1999,50&title=产品列表" -o table.png`
|
||
}
|
||
},
|
||
{
|
||
method: 'POST',
|
||
path: '/api/combine',
|
||
description: '将两张图表合并到一张图片中（支持横排/竖排）',
|
||
'Content-Type': 'application/json',
|
||
params: {
|
||
chart1: { type: 'object', required: true, description: '第一张图配置（同 /api/chart 参数）' },
|
||
chart2: { type: 'object', required: true, description: '第二张图配置（同 /api/chart 参数）' },
|
||
direction: { type: 'string', default: 'horizontal', options: ['horizontal', 'vertical'], description: '排列方向：horizontal 横排（左右）/ vertical 竖排（上下）' },
|
||
gap: { type: 'number', default: 24, description: '两图间距(px)' },
|
||
pixelRatio: { type: 'number', default: 2, description: '像素倍率（清晰度）' },
|
||
background: { type: 'string', default: '#ffffff', description: '背景色' }
|
||
},
|
||
returns: 'image/png',
|
||
example: {
|
||
request: `curl -X POST http://localhost:16016/api/combine \\
|
||
-H "Content-Type: application/json" \\
|
||
-d '{
|
||
"chart1": {"data": "产品, Q1, Q2\\n手机, 1200, 1800\\n平板, 800, 950", "title": "2024年销售", "chartType": "bar"},
|
||
"chart2": {"data": "月份, 营收\\n1月, 500\\n2月, 680\\n3月, 820", "title": "营收趋势", "chartType": "line"},
|
||
"direction": "horizontal"
|
||
}' -o combine.png`,
|
||
response: 'PNG 图片二进制流'
|
||
}
|
||
}
|
||
]
|
||
});
|
||
});
|
||
|
||
// ===== API: 双图合并生成图片 =====
|
||
// 将两张图（图表/表格均可）合并到一张图片中，支持横排（左右）或竖排（上下）
|
||
app.post('/api/combine', async (req, res) => {
|
||
try {
|
||
const body = req.body || {};
|
||
const chart1 = body.chart1 || {};
|
||
const chart2 = body.chart2 || {};
|
||
const direction = body.direction === 'vertical' ? 'vertical' : 'horizontal';
|
||
const gap = parseInt(body.gap) || 24;
|
||
const pixelRatio = parseInt(body.pixelRatio) || 2;
|
||
const background = body.background || '#ffffff';
|
||
|
||
if (!chart1.data || !chart2.data) {
|
||
return res.status(400).json({ error: 'chart1 和 chart2 都需要提供 data 参数（CSV 格式）' });
|
||
}
|
||
|
||
// 渲染单个子图（直接按目标尺寸渲染，避免二次缩放损失）
|
||
// 注意：必须先 toBuffer 再 chart.dispose()，dispose 会清空 canvas 内容！
|
||
const renderSub = async (params, w, h) => {
|
||
const option = buildChartOption(params);
|
||
const c = createCanvas(w * pixelRatio, h * pixelRatio);
|
||
const chart = echarts.init(c, null, {
|
||
renderer: 'canvas',
|
||
width: w,
|
||
height: h,
|
||
devicePixelRatio: pixelRatio
|
||
});
|
||
chart.setOption(option);
|
||
const buf = c.toBuffer('image/png');
|
||
chart.dispose();
|
||
const img = await loadImage(buf);
|
||
return { img, w, h };
|
||
};
|
||
|
||
const a = await renderSub(chart1, parseInt(chart1.width) || 640, parseInt(chart1.height) || 420);
|
||
const b = await renderSub(chart2, parseInt(chart2.width) || 640, parseInt(chart2.height) || 420);
|
||
|
||
let W, H, aRect, bRect;
|
||
if (direction === 'vertical') {
|
||
// 竖排（上下）：等宽对齐
|
||
const tw = Math.max(a.w, b.w);
|
||
aRect = { w: tw, h: Math.round(a.h * (tw / a.w)) };
|
||
bRect = { w: tw, h: Math.round(b.h * (tw / b.w)) };
|
||
W = tw;
|
||
H = aRect.h + bRect.h + gap;
|
||
} else {
|
||
// 横排（左右）：等高对齐
|
||
const th = Math.max(a.h, b.h);
|
||
aRect = { w: Math.round(a.w * (th / a.h)), h: th };
|
||
bRect = { w: Math.round(b.w * (th / b.h)), h: th };
|
||
W = aRect.w + bRect.w + gap;
|
||
H = th;
|
||
}
|
||
|
||
const canvas = createCanvas(W * pixelRatio, H * pixelRatio);
|
||
const ctx = canvas.getContext('2d');
|
||
ctx.fillStyle = background;
|
||
ctx.fillRect(0, 0, W * pixelRatio, H * pixelRatio);
|
||
|
||
if (direction === 'vertical') {
|
||
// 5 参数形式：drawImage(img, dx, dy, dw, dh)，源整图缩放到目标矩形
|
||
ctx.drawImage(a.img, 0, 0, aRect.w * pixelRatio, aRect.h * pixelRatio);
|
||
ctx.drawImage(b.img, 0, (aRect.h + gap) * pixelRatio, bRect.w * pixelRatio, bRect.h * pixelRatio);
|
||
} else {
|
||
ctx.drawImage(a.img, 0, 0, aRect.w * pixelRatio, aRect.h * pixelRatio);
|
||
ctx.drawImage(b.img, (aRect.w + gap) * pixelRatio, 0, bRect.w * pixelRatio, bRect.h * pixelRatio);
|
||
}
|
||
|
||
const buffer = canvas.toBuffer('image/png');
|
||
res.set({
|
||
'Content-Type': 'image/png',
|
||
'Content-Length': buffer.length,
|
||
'X-Combine-Direction': direction,
|
||
'X-Chart-Width': W,
|
||
'X-Chart-Height': H
|
||
});
|
||
res.send(buffer);
|
||
} catch (err) {
|
||
console.error('Combine error:', err);
|
||
res.status(500).json({ error: '双图合并失败: ' + err.message });
|
||
}
|
||
});
|
||
|
||
// ===== 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:${PORT}`);
|
||
console.log(`📡 图表API: http://0.0.0.0:${PORT}/api/chart`);
|
||
console.log(`📋 表格API: http://0.0.0.0:${PORT}/api/table`);
|
||
console.log(`🖼️ 合并API: http://0.0.0.0:${PORT}/api/combine`);
|
||
console.log(`📖 文档: http://0.0.0.0:${PORT}/api/docs`);
|
||
console.log(`❤️ 健康: http://0.0.0.0:${PORT}/api/health`);
|
||
});
|