我將models內原本FileField的upload_to參數取消讓他儲存到預設的位置
這樣在存入DB的時候才不會顯示資料夾upload
在後面取資料的時候也可以不用再修改檔案名稱
增加以下設定
docsystem_5/settings.py

MEDIA_ROOT = os.path.join(BASE_DIR, 'media')
MEDIA_URL = '/media/'

doc_info/models.py

class doc_warehouse(models.Model):
    upload_file = models.FileField(null=True, blank=True)

要記得執行以下

python manage.py makemigrations #告訴django依據model跟installed_app要改動哪些table 
python manage.py migrate #執行以上的變動 
python manage.py runserver #執行server

發現另存新檔的時候他會依照content-type & content-disposition的參數去解析檔案
所以要用dict的方式去反應 (dict放最後面以免文章過長)
doc_info/views.py

@login_required
def doc_download(request,doc_id):
    user = request.user
    Doc_warehouse = doc_warehouse.objects.filter(user_id=user.id)
    try:
        doc = Doc_warehouse.get(id=doc_id)
        upload_file_path = f"media/{str(doc.upload_file)}"
        upload_file_extension = str(Path(upload_file_path).suffix).lower()
        extexsion_dict = {
            ...
        }
        if os.path.exists(upload_file_path):
            with open(upload_file_path, 'rb') as file:
                response = HttpResponse(file.read(), charset='utf-8' )
                response['Content-Type'] = f"{extexsion_dict.get(upload_file_extension,'application/pdf')}"
                response['Content-Disposition'] = f"inline; filename={os.path.basename(upload_file_path.encode('utf-8').decode('ISO-8859-1'))}"
                return response
    except Exception as e:
        print(e)
        return HttpResponseNotFound('You have no access to this file')

呈現如下

extexsion_dict = {
    ".epub":"application/epub+zip",
    ".fif":"application/fractals",
    ".spl":"application/futuresplash",
    ".hta":"application/hta",
    ".hqx":"application/mac-binhex40",
    ".vsi":"application/ms-vsi",
    ".accdb":"application/msaccess",
    ".accda":"application/msaccess.addin",
    ".accdc":"application/msaccess.cab",
    ".accde":"application/msaccess.exec",
    ".accft":"application/msaccess.ftemplate",
    ".accdr":"application/msaccess.runtime",
    ".accdt":"application/msaccess.template",
    ".accdw":"application/msaccess.webapplication",
    ".one":"application/msonenote",
    ".doc":"application/msword",
    ".osdx":"application/opensearchdescription+xml",
    ".pdf":"application/pdf",
    ".p10":"application/pkcs10",
    ".p7c":"application/pkcs7-mime",
    ".p7s":"application/pkcs7-signature",
    ".cer":"application/pkix-cert",
    ".crl":"application/pkix-crl",
    ".ps":"application/postscript",
    ".xls":"application/vnd.ms-excel",
    ".xlsx":"application/vnd.ms-excel.12",
    ".xlam":"application/vnd.ms-excel.addin.macroEnabled.12",
    ".xlsb":"application/vnd.ms-excel.sheet.binary.macroEnabled.12",
    ".xlsm":"application/vnd.ms-excel.sheet.macroEnabled.12",
    ".xltm":"application/vnd.ms-excel.template.macroEnabled.12",
    ".thmx":"application/vnd.ms-officetheme",
    ".sst":"application/vnd.ms-pki.certstore",
    ".pko":"application/vnd.ms-pki.pko",
    ".cat":"application/vnd.ms-pki.seccat",
    ".ppt":"application/vnd.ms-powerpoint",
    ".pptx":"application/vnd.ms-powerpoint.12",
    ".ppam":"application/vnd.ms-powerpoint.addin.macroEnabled.12",
    ".pptm":"application/vnd.ms-powerpoint.presentation.macroEnabled.12",
    ".sldm":"application/vnd.ms-powerpoint.slide.macroEnabled.12",
    ".ppsm":"application/vnd.ms-powerpoint.slideshow.macroEnabled.12",
    ".potm":"application/vnd.ms-powerpoint.template.macroEnabled.12",
    ".pub":"application/vnd.ms-publisher",
    ".vsd":"application/vnd.ms-visio.viewer",
    ".docx":"application/vnd.ms-word.document.12",
    ".docm":"application/vnd.ms-word.document.macroEnabled.12",
    ".dotx":"application/vnd.ms-word.template.12",
    ".dotm":"application/vnd.ms-word.template.macroEnabled.12",
    ".wpl":"application/vnd.ms-wpl",
    ".xps":"application/vnd.ms-xpsdocument",
    ".odp":"application/vnd.oasis.opendocument.presentation",
    ".ods":"application/vnd.oasis.opendocument.spreadsheet",
    ".odt":"application/vnd.oasis.opendocument.text",
    ".pptx":"application/vnd.openxmlformats-officedocument.presentationml.presentation",
    ".sldx":"application/vnd.openxmlformats-officedocument.presentationml.slide",
    ".ppsx":"application/vnd.openxmlformats-officedocument.presentationml.slideshow",
    ".potx":"application/vnd.openxmlformats-officedocument.presentationml.template",
    ".xlsx":"application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
    ".xltx":"application/vnd.openxmlformats-officedocument.spreadsheetml.template",
    ".docx":"application/vnd.openxmlformats-officedocument.wordprocessingml.document",
    ".dotx":"application/vnd.openxmlformats-officedocument.wordprocessingml.template",
    ".appcontent-ms":"application/windows-appcontent+xml",
    ".z":"application/x-compress",
    ".solitairetheme8":"application/x-compressed",
    ".dtcp-ip":"application/x-dtcp1",
    ".gz":"application/x-gzip",
    ".itls":"application/x-itunes-itls",
    ".itms":"application/x-itunes-itms",
    ".itpc":"application/x-itunes-itpc",
    ".jtx":"application/x-jtx+xps",
    ".latex":"application/x-latex",
    ".nix":"application/x-mix-transfer",
    ".asx":"application/x-mplayer2",
    ".application":"application/x-ms-application",
    ".vsto":"application/x-ms-vsto",
    ".wmd":"application/x-ms-wmd",
    ".wmz":"application/x-ms-wmz",
    ".xbap":"application/x-ms-xbap",
    ".website":"application/x-mswebsite",
    ".p12":"application/x-pkcs12",
    ".p7b":"application/x-pkcs7-certificates",
    ".p7r":"application/x-pkcs7-certreqresp",
    ".pcast":"application/x-podcast",
    ".swf":"application/x-shockwave-flash",
    ".sit":"application/x-stuffit",
    ".tar":"application/x-tar",
    ".man":"application/x-troff-man",
    ".asx":"application/x-wmplayer",
    ".cer":"application/x-x509-ca-cert",
    ".zip":"application/x-zip-compressed",
    ".xaml":"application/xaml+xml",
    ".xht":"application/xhtml+xml",
    ".xml":"application/xml",
    ".zip":"application/zip",
    ".3gp":"audio/3gpp",
    ".3g2":"audio/3gpp2",
    ".aac":"audio/aac",
    ".aiff":"audio/aiff",
    ".amr":"audio/amr",
    ".au":"audio/basic",
    ".ec3":"audio/ec3",
    ".lpcm":"audio/l16",
    ".mid":"audio/mid",
    ".mid":"audio/midi",
    ".mp3":"audio/mp3",
    ".m4a":"audio/mp4",
    ".m4a":"audio/MP4A-LATM",
    ".mp3":"audio/mpeg",
    ".m3u":"audio/mpegurl",
    ".mp3":"audio/mpg",
    ".adts":"audio/vnd.dlna.adts",
    ".ac3":"audio/vnd.dolby.dd-raw",
    ".wav":"audio/wav",
    ".aiff":"audio/x-aiff",
    ".flac":"audio/x-flac",
    ".m4a":"audio/x-m4a",
    ".m4r":"audio/x-m4r",
    ".mka":"audio/x-matroska",
    ".mid":"audio/x-mid",
    ".mid":"audio/x-midi",
    ".mp3":"audio/x-mp3",
    ".mp3":"audio/x-mpeg",
    ".m3u":"audio/x-mpegurl",
    ".mp3":"audio/x-mpg",
    ".wax":"audio/x-ms-wax",
    ".wma":"audio/x-ms-wma",
    ".wav":"audio/x-wav",
    ".dib":"image/bmp",
    ".gif":"image/gif",
    ".jpg":"image/jpeg",
    ".jps":"image/jps",
    ".mpo":"image/mpo",
    ".jpg":"image/pjpeg",
    ".png":"image/png",
    ".pns":"image/pns",
}

-參考資料: https://www.itread01.com/content/1546929737.html