[ django output writing to a text file as temporary storage (over-written with each submission) ]

I have managed to configure a system, using django, that allows me to upload a file to my media-folder. I have (using simple-html) included a drop-down menu that will specify parameters that will be considered when processing the uploaded file in a pipeline.

<form action="{% url "list" %}" method="post" enctype="multipart/form-data">
    <tr>
        {% csrf_token %}
        <p>{{ form.non_field_errors }}</p>

        <p>{{ form.docfile.label_tag }} {{ form.docfile.help_text }}</p>

        <p>
            {{ form.docfile.errors }}
            {{ form.docfile }}
        </p>
    </tr>

    <tr>    
    <th>Genome Dataset</th>
     <TD WIDTH = 80% ALIGN=left VALIGN=top>
      <SELECT NAME='genome' ID='genome'>
        <OPTION>All</OPTION>
        <OPTION>Neanderthal</OPTION>
        <OPTION>hg38 Human</OPTION>
        <OPTION>Denisovan</OPTION>
      </SELECT>
    </tr>   
    <p><input type="submit" value="Upload"/></p>
    </form>

I need to send the selected dropdown option to a text file. and I have attempted to do so as follows in views.py. However. while the file uploads to the media folder successfully, no text file manifests in the media folder- which is needed.

def GenomesView(request):
   if request.method == 'GET':
     getgen = request.GET.get('genome')
     content = ContentFile(getgen)
     f = open(os.path.join(settings.MEDIA_ROOT, 'file.txt'), 'w')
     myfile = File(f)
     myfile.write(getgen)
     myfile.close()

The location of the media folder is as below in settings.

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

Hence my question is how do I take the selected option forms the drop-down and each time the file is uploaded to the site, the selection is sent to text file that will be over-written for each new submission (acting as a temporary storage for the selected option parameter i.e "Neanderthall" etc. as seen in code above)?

Answer 1

It looks like you are using a form to POST this data, but only writing to the file if the request is a GET. Try changing it to a POST. Also, since request.POST.get('genome') should return a string for you to write to the file there is no need to wrap it in a ContentFile. Try this:

if request.method == 'POST':
    getgen = request.POST.get('genome')
    with open(os.path.join(settings.MEDIA_ROOT, 'file.txt'), 'w') as f:
        f.write(getgen)

I also changed your file handling to use a context manager.