feat: download_pdf尝试从openalex下载

apps/resm/tasks.py

@@ -322,7 +322,7 @@ def download_pdf(paper_id):
         res = requests.get(paper.oa_url, headers=headers, timeout=(3, 15))
     except requests.RequestException as e:
         paper.save_fail_reason("oa_url_request_error")
-        return f"request_error_final: {str(e)}"
+        return save_pdf_from_openalex(paper)
     
     if res.status_code == 200:
         # 检查是否是PDF文件：检查魔数 %PDF 或 content-type
@@ -339,9 +339,12 @@ def download_pdf(paper_id):
             paper.save(update_fields=["has_fulltext", "has_fulltext_pdf", "fetch_status", "update_time"])
             return "success"
         else:
-            paper.save_fail_reason("oa_url_not_pdf")
-            return "not_pdf"
+            return save_pdf_from_openalex(paper)
     else:
+        return save_pdf_from_openalex(paper)
+
+
+def save_pdf_from_openalex(paper:Paper):
     # 尝试openalex下载
     try:
         res = requests.get(url=f"https://content.openalex.org/works/{paper.openalex_id}.pdf",