Openpyxl Django - django

Trying to automate modifying an Ecxel file using openpyxl lib and below code works:
def modify_excel_view(request):
wb = openpyxl.load_workbook('C:\\my_dir\\filename.xlsx')
sh1 = wb['Sheet1']
row = sh1.max_row
column = sh1.max_column
for i in range(2, row + 1):
# ...some_code...
wb.save('C:\\my_dir\\new_filename.xlsx')
return render(request, 'my_app/convert.html', {'wb': wb})
But how to implement a similar method without static (hardcoding) path to file and a filename? Like choosing xlsx file from modal window?
Saving modified copy on a desktop by default? (Maybe like 'ReportLab library': response.write(pdf)=>return response. And it saving on the desktop by default.)
Thank you in advance!

You can send the file path and name as POST parameters and extract them in the views.py function using request.POST.get('file_path').
Just add a line to save the copy to the desktop before returning.

Related

Directing Output Paths of Altered Files

How can I direct the destination of the output file to my db?
My models.py is structured like so:
class Model(models.Model):
char = models.CharField(max_length=50, null=False, blank=False)
file = models.FileField(upload_to=upload_location, null=True, blank=True)
I have the user enter a value for 'char', and then the value of 'char' is printed on to a file. The process of successfully printing onto the file is working, however, the file is outputting to my source directory.
My goal is to have the output file 'pdf01.pdf' output to my db and be represented as 'file' so that the admin can read it.
Much of the information in the Dango docs has been focussed on directing the path of objects imported by the user directly, not on files that have been created internally. I have been reading mostly from these docs:
Models-Fields
Models
File response objects
Outputting PDFs
I have seen it recommend to write to a buffer, not a file, then save the buffer contents to my db however I haven't been able to find many examples of how to do that relevant to my situation online.
Perhaps there is a relevant gap in my knowledge regarding buffers and BytesIO? Here is the function I have been using to alter the pdf, I have been using BytesIO to temporarily store files throughout the process but have not been able to figure out how to use it to direct the output anywhere specific.
can = canvas.Canvas(BytesIO(), pagesize=letter)
can.drawString(10, 10, char)
can.save()
BytesIO().seek(0)
text_pdf = PdfFileReader(BytesIO())
base_file = PdfFileReader(open("media/01.pdf", "rb"))
page = base_file.getPage(0)
page.mergePage(text_pdf.getPage(0))
PdfFileWriter().addPage(page)
PdfFileWriter().write(open("pdf01.pdf", "wb")
FileField does not store files directly in the database. Files get uploaded in a location on the filesystem determined by the upload_to argument. Only some metadata are stored in the DB, including the path of the file in your filesystem.
If you want to have the contents of the files in the database, you could create a new File model that includes a BinaryField to store the data and a CharField to store the URL from which the file can be fetched. To feed the data of PdfFileWriter to the binary field of Django, perhaps the most appropriate would be to use BytesIO.
I found this workaround to direct the file to a desired location (in this case both my media_cdn folder and also output it to an admin.)
I set up an admin action to perform the function that outputs the file so the admin will have access to both the output version in the form of both an HTTP response and through the media_cdn storage.
Hope this helps anyone who struggles with the same problem.
#admin.py
class edit_and_output():
def output:
author = Account.email
#alter file . . .
with open('media_cdn/account/{0}.pdf'.format(author), 'wb') as out_file:
output.write(out_file)
response = HttpResponse(content_type='application/pdf')
response['Content-Disposition'] = 'attachment;filename="{0}.pdf"'.format(author)
output.write(response)

get list of files in a sharepoint directory using python

I have a url for sharepoint directory(intranet) and need an api to return list of files in that directory given the url. how can I do that using python?
Posting in case anyone else comes across this issue of getting files from a SharePoint folder from just the folder path.
This link really helped me do this: https://github.com/vgrem/Office365-REST-Python-Client/issues/98. I found so much info about doing this for HTTP but not in Python so hopefully someone else needs more Python reference.
I am assuming you are all setup with client_id and client_secret with the Sharepoint API. If not you can use this for reference: https://learn.microsoft.com/en-us/sharepoint/dev/solution-guidance/security-apponly-azureacs
I basically wanted to grab the names/relative urls of the files within a folder and then get the most recent file in the folder and put into a dataframe.
I'm sure this isn't the "Pythonic" way to do this but it works which is good enough for me.
!pip install Office365-REST-Python-Client
from office365.runtime.auth.client_credential import ClientCredential
from office365.runtime.client_request_exception import ClientRequestException
from office365.sharepoint.client_context import ClientContext
from office365.sharepoint.files.file import File
import io
import datetime
import pandas as pd
sp_site = 'https://<org>.sharepoint.com/sites/<my_site>/'
relative_url = "/sites/<my_site/Shared Documents/<folder>/<sub_folder>"
client_credentials = ClientCredential(credentials['client_id'], credentials['client_secret'])
ctx = ClientContext(sp_site).with_credentials(client_credentials)
libraryRoot = ctx.web.get_folder_by_server_relative_path(relative_url)
ctx.load(libraryRoot)
ctx.execute_query()
#if you want to get the folders within <sub_folder>
folders = libraryRoot.folders
ctx.load(folders)
ctx.execute_query()
for myfolder in folders:
print("Folder name: {0}".format(myfolder.properties["ServerRelativeUrl"]))
#if you want to get the files in the folder
files = libraryRoot.files
ctx.load(files)
ctx.execute_query()
#create a dataframe of the important file properties for me for each file in the folder
df_files = pd.DataFrame(columns = ['Name', 'ServerRelativeUrl', 'TimeLastModified', 'ModTime'])
for myfile in files:
#use mod_time to get in better date format
mod_time = datetime.datetime.strptime(myfile.properties['TimeLastModified'], '%Y-%m-%dT%H:%M:%SZ')
#create a dict of all of the info to add into dataframe and then append to dataframe
dict = {'Name': myfile.properties['Name'], 'ServerRelativeUrl': myfile.properties['ServerRelativeUrl'], 'TimeLastModified': myfile.properties['TimeLastModified'], 'ModTime': mod_time}
df_files = df_files.append(dict, ignore_index= True )
#print statements if needed
# print("File name: {0}".format(myfile.properties["Name"]))
# print("File link: {0}".format(myfile.properties["ServerRelativeUrl"]))
# print("File last modified: {0}".format(myfile.properties["TimeLastModified"]))
#get index of the most recently modified file and the ServerRelativeUrl associated with that index
newest_index = df_files['ModTime'].idxmax()
newest_file_url = df_files.iloc[newest_index]['ServerRelativeUrl']
# Get Excel File by newest_file_url identified above
response= File.open_binary(ctx, newest_file_url)
# save data to BytesIO stream
bytes_file_obj = io.BytesIO()
bytes_file_obj.write(response.content)
bytes_file_obj.seek(0) # set file object to start
# load Excel file from BytesIO stream
df = pd.read_excel(bytes_file_obj, sheet_name='Sheet1', header= 0)
Here is another helpful link of the file properties you can view: https://learn.microsoft.com/en-us/previous-versions/office/developer/sharepoint-rest-reference/dn450841(v=office.15). Scroll down to file properties section.
Hopefully this is helpful to someone. Again, I am not a pro and most of the time I need things to be a bit more explicit and written out. Maybe others feel that way too.
You need to do 2 things here.
Get a list of files (which can be directories or simple files) in
the directory of your interest.
Loop over each item in this list of files and check if
the item is a file or a directory. For each directory do the same as
step 1 and 2.
You can find more documentation at https://learn.microsoft.com/en-us/sharepoint/dev/sp-add-ins/working-with-folders-and-files-with-rest#working-with-files-attached-to-list-items-by-using-rest
def getFilesList(directoryName):
...
return filesList
# This will tell you if the item is a file or a directory.
def isDirectory(item):
...
return true/false
Hope this helps.
I have a url for sharepoint directory
Assuming you asking about a library, you can use SharePoint's REST API and make a web service call to:
https://yourServer/sites/yourSite/_api/web/lists/getbytitle('Documents')/items?$select=Title
This will return a list of documents at: https://yourServer/sites/yourSite/Documents
See: https://msdn.microsoft.com/en-us/library/office/dn531433.aspx
You will of course need the appropriate permissions / credentials to access that library.
You can not use "server name/sites/Folder name/Subfolder name/_api/web/lists/getbytitle('Documents')/items?$select=Title" as URL in SharePoint REST API.
The URL structure should be like below considering WebSiteURL is the URL of site/subsite containing document library from which you are trying to get files and Documents is the Display name of document library:
WebSiteURL/_api/web/lists/getbytitle('Documents')/items?$select=Title
And if you want to list metadata field values you should add Field names separated by comma in $select.
Quick tip: If you are not sure about the REST API URL formation. Try pasting the URL in Chrome browser (you must be logged in to SharePoint site with appropriate permissions) and see if you get proper result as XML if you are successful then update the REST URL and run the code. This way you will save time of running your python code.

Django - writing a PDF created with xhtml2pdf to server's disk

I'm trying to write a script that will save a pdf created by xhtml2pdf directly to the server, without doing the usual route of prompting the user to download it to their computer. Documents() is the Model I am trying to save to, and the new_project and output_filename variables are set elsewhere.
html = render_to_string(template, RequestContext(request, context)).encode('utf8')
result = open(output_filename, "wb")
pdf = CreatePDF(src=html, dest=results, path = "", encoding = 'UTF-8', link_callback=link_callback) #link callback was originally set to link_callback, defined below
result.close()
if not pdf.err:
new_doc=Documents()
new_doc.project=new_project
new_doc.posted_by=old_mess[0].from_user_fk.username
new_doc.documents = result
new_doc.save()
With this configuration when it reaches new_doc.save() I get the error: 'file' object has no attribute '_committed'
Does anyone know how I can fix this? Thanks!
After playing around with it I found a working solution. The issue was I was not creating the new Document while result (the pdf) was still open.
"+" needed to be added to open() so that the pdf file was available for reading and writing, and not just writing.
Note that this does save the pdf in a different folder first (Files). If that is not the desired outcome for your application you will need to delete it.
html = render_to_string(template, RequestContext(request, context)).encode('utf8')
results = StringIO()
result = open("Files/"+output_filename, "w+b")
pdf = CreatePDF(src=html, dest=results, path = "", encoding = 'UTF-8', link_callback=link_callback) #link callback was originally set to link_callback, defined below
if not pdf.err:
result.write(results.getvalue())
new_doc=Documents()
new_doc.project=new_project
new_doc.documents.save(output_filename, File(result))
new_doc.posted_by=old_mess[0].from_user_fk.username
new_doc.save()
result.close()

Django csv output in Excel

Hi I have a simple view which returns a csv file of a queryset which is generated from a mysql db using utf-8 encoding:
def export_csv(request):
...
response = HttpResponse(mimetype='text/csv')
response['Content-Disposition'] = 'attachment; filename=search_results.csv'
writer = csv.writer(response, dialect=csv.excel)
for item in query_set:
writer.writerow(smart_str(item))
return response
return render(request, 'search_results.html', context)
This works fine as a CSV file, and can be opened in text editors, LibreOffice etc. without problem.
However, I need to supply a file which can be opened in MS Excel in Windows without errors. If I have strings with latin characters in the queryset such as 'Española' then the output in Excel is 'Española'.
I tried this blogpost but it didn't help. I also know abut the xlwt package, but I am curious if there is a way of correcting the output, using the CSV method I have at the moment.
Any help much appreciated.
Looks like there is not a uniform solution for all version of Excel.
Your best bet migth be to go with openpyxl, but this is rather complicated and requiers
separate handling of downloads for excel users which is not optimal.
Try adding byte order marks at the beginnign (0xEF, 0xBB, 0xBF) of file. See microsoft-excel-mangles-diacritics-in-csv-files
There is another similar post.
You might give python-unicodecsv a go. It replaces the python csv module which doesn't handle Unicode too gracefully.
Put the unicodecsv folder somehwere you can import it or install via setup.py
Import it into your view file, eg :
import unicodecsv as csv
I found out there are 3 things to do for Excel to open unicode csv files properly:
Use utf-16-le charset
Insert utf-16 byte order mark to the beginning of exported file
Use tabs instead of commas in csv
So, this should make it work in Python 3.7 and Django 2.2
import codecs
...
def export_csv(request):
...
response = HttpResponse(content_type='text/csv', charset='utf-16-le')
response['Content-Disposition'] = 'attachment; filename=search_results.csv'
response.write(codecs.BOM_UTF16_LE)
writer = csv.writer(response, dialect='excel-tab')
for item in query_set:
writer.writerow(smart_str(item))
return response

How to process an uploaded KML file in GeoDjango

I wrote a cmd line routine to import a kml file into a geoDjango application, which works fine when you feed it a locally saved KML file path (using the datasource object).
Now I am writing a web file upload dialog, to achieve the same thing. This is the beginning of the code that I have, problem is, that the GDAL DataSource object does not seem to understand Djangos UploadedFile format. It is held in memory and not a file path as expected.
What would be the best strategy to convert the UploadedFile to a normal file, and access this through a path? I dont want to keep the file after processing.
def createFeatureSet(request):
if request.method == 'POST':
inMemoryFile = request.FILES['myfile']
name = inMemoryFile.name
POSTGIS_SRID = 900913
ds = DataSource(inMemoryFile) #This line doesnt work!!!
for layer in ds:
if layer.geom_type in (OGRGeomType('Point'), OGRGeomType('Point25D'), OGRGeomType('MultiPoint'), OGRGeomType('MultiPoint25D')):
layerGeomType = OGRGeomType('MultiPoint').django
elif layer.geom_type in (OGRGeomType('LineString'),OGRGeomType('LineString25D'), OGRGeomType('MultiLineString'), OGRGeomType('MultiLineString25D')):
layerGeomType = OGRGeomType('MultiLineString').django
elif layer.geom_type in (OGRGeomType('Polygon'), OGRGeomType('Polygon25D'), OGRGeomType('MultiPolygon'), OGRGeomType('MultiPolygon25D')):
layerGeomType = OGRGeomType('MultiPolygon').django
DataSource is a wrapper around GDAL's C API and needs an actual file. You'll need to write your upload somewhere on the disk, for insance using a tempfile. Then you can pass the file to DataSource.
Here is a suggested solution using a tempfile. I put the processing code in its own function which is now called.
f = request.FILES['myfile']
temp = tempfile.NamedTemporaryFile(delete=False)
temp.write(f.read())
temp.close()
createFeatureSet(temp.name, source_SRID= 900913)