django文件的下载实现

• 在后台通过脚本生成了想要的结果，需要提供一个下载链接返回给前端用户
  html代码如下：

<div class="col-md-12">
    <button onclick="window.location.href='/download/?id={{ expfile }} ' ">差异表达基因的结果</button>
    <br>
    <br>
    <button onclick="window.location.href='/download/?id={{ difffile }}' ">基因在不同样品中的表达量结果</button>
    <h1>表格显示的结果是查询的差异表达基因在不同数据库的差异倍数，pvalue，qvalue结果</h1>
</div>

在views.py里面传递一个文件的路径即可，我这里是将文件的路径存入得了数据库，然后再读出来的，这样可以随时获取差异基因和表达量文件所在的位置，同时进行后续的画图操作

def showtable(request):
  gse_direct = ["Liver_cancer", "Myocardial_Infarction", "Macrophage", "VIH", "Renal_fibrosis"]
    if request.method == 'POST':
  # print (request.POST)
 #获取从表单以POST方式提交过来的数据  query_gene_list = request.POST.get('input_gene_list')
        disease_type = request.POST.get('disease_type')
        species_type = request.POST.get('spcies_type')
        tissue_type = request.POST.get('tissue_type')
        #######
  if len(query_gene_list) == 0:
  return render(request, 'error01.html', {'errorlog': "您输入的基因列表为空"})
        elif query_gene_list.replace("
", "").replace("
", "").encode('UTF-8').isalnum():
  genes = getgenelist(query_gene_list)
            genes = map(lambda x: x.upper(), genes)
            genes = tuple(genes)
        else:
  return render(request, 'error01.html', {'errorlog': "您输入的基因列表包含非法字符串，请检查你的基因列表"})
        if disease_type in gse_direct and len(genes) !=0:
  datapath,rpath=createpath()
            gsepath = datapath + "/" + disease_type
            degfilelist, expfilelist = fetch_gene.get_exp_list(gsepath)
            difftable,degfilename,expfilename = fetch_gene.get_result(genes, degfilelist, expfilelist, gsepath, rpath)
            # return HttpResponse("成功生成了你想要的文件")
  downexp = rpath + "/" + degfilename
            downdiff = rpath + "/" + expfilename
            inputgenenum = len(genes)
            Resultpath.objects.all().delete()
            Resultpath.objects.create(resultpath=rpath, expfilepath=downexp, difffilepath=downdiff,
  inputgenenum=inputgenenum,
  picpath=rpath)
            tablepre = DEGs.objects.all()
            resultdata = Resultpath.objects.all()

            # print (resultdata)
 #获取表头  hlist = ["Database_type", "gene_id", "log2FoldChange", "pvalue", "padj"]
            tablenum = int(resultdata.values('inputgenenum')[0]['inputgenenum'])+1
  resultpath = resultdata.values('resultpath')[0]['resultpath']
            downexp = resultdata.values('expfilepath')[0]['expfilepath']
            downdiff = resultdata.values('difffilepath')[0]['difffilepath']
            picpath = resultdata.values('picpath')[0]['picpath']
            paginator = Paginator(tablepre, tablenum)
            page = request.GET.get('page')
            if page: # 判断：获取当前页码的数据集，这样在模版就可以针对当前的数据集进行展示
  data_list = paginator.page(page).object_list
            else:
  data_list = paginator.page(1).object_list
            try: # 实现分页对象，分别判断当页码存在/不存在的情况，返回当前页码对象
  page_object = paginator.page(page)
            except PageNotAnInteger:
  page_object = paginator.page(1)
            except EmptyPage:
  page_object = paginator.page(paginator.num_pages)
            return render(request, 'show_table2.html', {
                'page_object': page_object,
  'data_list': data_list,
  'myList': hlist,
  'resultpath': resultpath,
  'expfile': downexp,
  'difffile': downdiff,
  'img': "output.pdf"
  })
        else:
  return HttpResponse("其他的数据库还未开放，目前只能查询Liver_cancer数据库." )
    else:
  # 获取表格数据
  tablepre = DEGs.objects.all()
        resultdata = Resultpath.objects.all()
        #获取表头
  hlist = ["Database_type", "gene_id", "log2FoldChange", "pvalue", "padj"]
        print (Resultpath.objects.values('inputgenenum')[0]['inputgenenum'])
        tablenum = int(resultdata.values('inputgenenum')[0]['inputgenenum'])+1
  resultpath = resultdata.values('resultpath')[0]['resultpath']
        downexp = resultdata.values('expfilepath')[0]['expfilepath']
        downdiff = resultdata.values('difffilepath')[0]['difffilepath']
        print (downdiff)
        print (downexp)
        picpath = resultdata.values('picpath')[0]['picpath']
        paginator = Paginator(tablepre, tablenum)
        page = request.GET.get('page')
        if page: # 判断：获取当前页码的数据集，这样在模版就可以针对当前的数据集进行展示
  data_list = paginator.page(page).object_list
        else:
  data_list = paginator.page(1).object_list
        try: # 实现分页对象，分别判断当页码存在/不存在的情况，返回当前页码对象
  page_object = paginator.page(page)
        except PageNotAnInteger:
  page_object = paginator.page(1)
        except EmptyPage:
  page_object = paginator.page(paginator.num_pages)
        # 分页功能
  return render(request, 'show_table2.html', {
            'page_object': page_object,
  'data_list': data_list,
  'myList': hlist,
  'resultpath': resultpath,
  'expfile': downexp,
  'difffile': downdiff,
  'img': "output.pdf"
  })
        # return render(request, "show_table2.html")
 # return HttpResponse("ok") # return render(request,'download.html',{'resultpath':resultpath,'expfile':downexp,'difffile':downdiff})

来自为知笔记(Wiz)