From d0b6240c7d294d4f1352436efcd3113bfb273f08 Mon Sep 17 00:00:00 2001
From: stae1102 <stae1102@gmail.com>
Date: Sat, 2 Nov 2024 17:42:56 +0900
Subject: [PATCH] refactor: get og data by using object

---
 src/contents/util/content.util.ts | 152 ++++++++++++++++++++----------
 1 file changed, 100 insertions(+), 52 deletions(-)

diff --git a/src/contents/util/content.util.ts b/src/contents/util/content.util.ts
index 5298dba..a4af428 100644
--- a/src/contents/util/content.util.ts
+++ b/src/contents/util/content.util.ts
@@ -1,64 +1,112 @@
-import { BadRequestException } from '@nestjs/common';
+import {
+  BadRequestException,
+  InternalServerErrorException,
+} from '@nestjs/common';
 import * as cheerio from 'cheerio';
-import axios from 'axios';
+import axios, { AxiosResponse } from 'axios';
 
-export const getLinkInfo = async (link: string) => {
-  let title: string | undefined = '';
-  let coverImg: string | undefined = '';
-  let description: string | undefined = '';
-  let siteName: string | undefined;
+interface OGData {
+  title: string;
+  description: string;
+  image: string;
+  url: string;
+  type: string;
+  site_name: string;
+  [key: string]: string; // 추가 OG 태그를 위한 인덱스 시그니처
+}
 
-  if (!link.match(/^(http|https):\/\//)) {
-    link = `http://${link}`;
+class OGCrawler {
+  private readonly timeout: number;
+  private readonly userAgent: string;
+  private readonly maxRedirects = 5;
+
+  constructor(options: { timeout?: number; userAgent?: string } = {}) {
+    this.timeout = options.timeout || 5000;
+    this.userAgent =
+      options.userAgent || 'Mozilla/5.0 (compatible; OGCrawler/1.0)';
   }
 
-  // ! TODO 크롤링에서 대략 초 단위 시간 소요 -> 개선 필요
-  await axios
-    .get(link, {
-      headers: {
-        'User-Agent': 'Mozilla/5.0 (compatible; OGCrawler/1.0)',
-      },
-    })
-    .then((res) => {
-      if (res.status !== 200) {
-        throw new BadRequestException('잘못된 링크입니다.');
-      } else {
-        const data = res.data;
-        if (typeof data === 'string') {
-          const $ = cheerio.load(data);
-          title =
-            $('title').text() !== ''
-              ? $('title').text() || $('meta[name="title"]').attr('content')
-              : 'Untitled';
-          $('meta').each((i, el) => {
-            const meta = $(el);
-            if (meta.attr('property') === 'og:image') {
-              coverImg = meta.attr('content');
-            }
-            if (meta.attr('property') === 'og:description') {
-              description = meta.attr('content');
-            }
-            if (meta.attr('property') === 'og:site_name') {
-              siteName = meta.attr('content');
-            }
-          });
-        }
+  public async fetch(url: string): Promise<OGData> {
+    try {
+      const response: AxiosResponse = await axios({
+        method: 'get',
+        url,
+        timeout: this.timeout,
+        headers: {
+          'User-Agent': this.userAgent,
+        },
+        maxRedirects: this.maxRedirects,
+      });
+
+      return this.parse(response.data);
+    } catch (error) {
+      if (error instanceof Error) {
+        throw new InternalServerErrorException(
+          `Failed to fetch URL: ${error.message}`,
+        );
       }
-    })
-    .catch((e) => {
-      // Control unreachable link
-      // if(e.message === 'Request failed with status code 403') {
-      // 403 에러가 발생하는 링크는 크롤링이 불가능한 링크이다.
-      // }
-      for (let idx = 1; idx < 3; idx++) {
-        if (link.split('/').at(-idx) !== '') {
-          title = link.split('/').at(-idx);
-          break;
-        }
+      throw new InternalServerErrorException('An unknown error occurred');
+    }
+  }
+
+  private parse(html: string): OGData {
+    const $ = cheerio.load(html);
+    const ogData: Partial<OGData> = {};
+
+    // OG 태그 파싱
+    $('meta[property^="og:"]').each((_, element) => {
+      const property = $(element).attr('property')?.replace('og:', '');
+      const content = $(element).attr('content');
+
+      if (property && content) {
+        ogData[property as keyof OGData] = content;
       }
-      title = title ? title : 'Untitled';
     });
 
+    // 기본 메타 태그 백업 파싱
+    if (!ogData.title) {
+      ogData.title =
+        $('title').text() || $('meta[name="title"]').attr('content') || '';
+    }
+
+    if (!ogData.description) {
+      ogData.description = $('meta[name="description"]').attr('content') || '';
+    }
+
+    // 이미지 URL 정규화
+    if (ogData.image && !ogData.image.startsWith('http')) {
+      const baseUrl = $('base').attr('href');
+      if (baseUrl) {
+        try {
+          ogData.image = new URL(ogData.image, baseUrl).href;
+        } catch (error) {
+          console.warn('Failed to normalize image URL:', error);
+        }
+      }
+    }
+
+    // 필수 필드가 있는 완성된 객체 반환
+    return {
+      title: ogData.title || '',
+      description: ogData.description || '',
+      image: ogData.image || '',
+      url: ogData.url || '',
+      type: ogData.type || '',
+      site_name: ogData.site_name || '',
+      ...ogData, // 추가 OG 태그 포함
+    };
+  }
+}
+
+export const getLinkInfo = async (link: string) => {
+  const crawler = new OGCrawler();
+  const ogData = await crawler.fetch(link);
+
+  const title = ogData.title;
+  const description = ogData.description;
+  const coverImg = ogData.image;
+  const siteName = ogData.site_name;
+
   return {
     title,
     description,