Lightning Web コンポーネント（LWC）を使って帳票出力してみた

/**
 * 請求PDFコントローラー
 */
public with sharing class InvoicePdfController {
    @AuraEnabled(cacheable=true)
    public static Invoice__c getInvoiceData(Id invoiceId) {
        List<Invoice__c> invoices = [
            SELECT Id, Name, Account__r.Name, InvoiceDate__c, TotalAmount__c,
                (
                    SELECT Id, Name, ProductName__c, UnitPrice__c, Quantity__c, Amount__c
                    FROM InvoiceLines__r
                    ORDER BY Name ASC
                )
            FROM Invoice__c
            WHERE Id = :invoiceId
            WITH USER_MODE
            LIMIT 1
        ];
        return invoices.isEmpty() ? null : invoices.get(0);
    }
}

/**
 * 請求PDF
 */
import { LightningElement, api } from 'lwc';
import { ShowToastEvent } from 'lightning/platformShowToastEvent';
import { loadScript } from 'lightning/platformResourceLoader';
import JSPDF_RESOURCE from '@salesforce/resourceUrl/jsPDF';
import getInvoiceData from '@salesforce/apex/InvoicePdfController.getInvoiceData';

const FONT_FILE_NAME = 'BIZUDMincho-Regular.ttf';
const FONT_NAME = 'BIZUDMincho';

export default class InvoicePdfGenerator extends LightningElement {
    @api recordId;
    isGenerating = false;

    @api async invoke() {
        if (this.isGenerating) return;
        this.isGenerating = true;
        this.dispatchEvent(new ShowToastEvent({ title: 'PDF生成中...' }));

        try {
            // jsPDF読み込み
            await loadScript(this, `${JSPDF_RESOURCE}/jspdf.umd.min.js`);
            await loadScript(this, `${JSPDF_RESOURCE}/jspdf.plugin.autotable.min.js`);

            // フォント読み込み
            const response = await fetch(`${JSPDF_RESOURCE}/${FONT_FILE_NAME}`);
            if (!response.ok) {
                throw new Error(`フォント読み込みエラー (${response.status})`);
            }
            const font = await response.bytes();
            const base64font = font.toBase64();

            // 請求データ取得
            const invoice = await getInvoiceData({ invoiceId: this.recordId });
            const invoiceLines = invoice.InvoiceLines__r || [];
            const accountName = invoice.Account__r?.Name || '';

            // jsPDF初期化
            const { jsPDF } = window.jspdf;
            const pdf = new jsPDF({ orientation: 'portrait', unit: 'mm', format: 'a4' });

            // フォント登録
            pdf.addFileToVFS(FONT_FILE_NAME, base64font);
            pdf.addFont(FONT_FILE_NAME, FONT_NAME, 'normal');
            pdf.setFont(FONT_NAME);

            const pageWidth = pdf.internal.pageSize.width; // ページ横幅
            const horizontalMargin = 15; // 水平マージン
            let startY = 20; // 描画開始Y座標

            // ヘッダー
            pdf.setFontSize(18);
            pdf.text('請求書', pageWidth/2, startY, { align: 'center' });
            pdf.setFontSize(10);
            startY += 15;
            pdf.text(`${accountName} 御中`, horizontalMargin, startY, { align: 'left' });
            pdf.text(`${this.formatDate(invoice.InvoiceDate__c)}`, pageWidth-horizontalMargin, startY, { align: 'right' });

            // 明細テーブル
            startY += 20;
            pdf.autoTable({
                startY: startY,
                tableWidth: 180,
                margin: { horizontal: 'center' },
                head: [['内容', '単価', '数量', '金額']],
                body: invoiceLines.map((line) => [
                    line.ProductName__c,
                    this.formatCurrency(line.UnitPrice__c),
                    this.formatNumber(line.Quantity__c),
                    this.formatCurrency(line.Amount__c),
                ]),
                theme: 'grid',
                styles: {
                    font: FONT_NAME,
                    fontStyle: 'normal',
                    fontSize: 10,
                    lineWidth: 0.2,
                    cellPadding: 3,
                },
                headStyles: {
                    font: FONT_NAME,
                    fontStyle: 'normal',
                    fillColor: [230, 230, 230],
                    textColor: [0, 0, 0],
                    halign: 'center',
                },
                columnStyles: {
                    0: { cellWidth: 80 },
                    1: { cellWidth: 40, halign: 'right' },
                    2: { cellWidth: 20, halign: 'right' },
                    3: { cellWidth: 40, halign: 'right' },
                }
            });

            // 合計金額
            startY = pdf.lastAutoTable.finalY + 10;
            pdf.setFontSize(10);
            pdf.text(`合計金額 ${this.formatCurrency(invoice.TotalAmount__c)}`, pageWidth-horizontalMargin, startY, { align: 'right' });

            // ファイル名
            const today = new Date();
            const [yyyy, mm, dd] = [
                today.getFullYear(),
                String(today.getMonth() + 1).padStart(2, '0'),
                String(today.getDate()).padStart(2, '0'),
            ];
            const fileName = `${invoice.Name}-${yyyy}${mm}${dd}.pdf`;

            // PDF保存
            pdf.save(fileName);
        } catch (error) {
            const errorMessage = error?.body?.message || error?.message || '予期せぬエラーが発生しました。';
            this.dispatchEvent(new ShowToastEvent({ title: 'エラーが発生しました', message: errorMessage, variant: 'error' }));
        } finally {
            this.isGenerating = false;
        }
    }

    formatDate(dateStr) {
        if (!dateStr) return '';
        const d = new Date(dateStr);
        const [yyyy, mm, dd] = [
            d.getFullYear(),
            String(d.getMonth() + 1).padStart(2, '0'),
            String(d.getDate()).padStart(2, '0'),
        ];
        return `${yyyy}年${mm}月${dd}日`;
    }

    formatNumber(value) {
        if (!value) return '0';
        return Number(value).toLocaleString('ja-JP');
    }

    formatCurrency(value) {
        return `${this.formatNumber(value)} 円`;
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<LightningComponentBundle xmlns="http://soap.sforce.com/2006/04/metadata">
    <apiVersion>67.0</apiVersion>
    <isExposed>true</isExposed>
    <targets>
        <target>lightning__RecordAction</target>
    </targets>
    <targetConfigs>
        <targetConfig targets="lightning__RecordAction">
            <actionType>Action</actionType>
        </targetConfig>
    </targetConfigs>
</LightningComponentBundle>