Let users upload a contact list to use later

We increasingly have teams wanting to do business-continuity type
messaging. They might be without access to their normal systems, which
is where they would otherwise go to get the list of email addresses or
phone numbers.

So we want to give them a place in Notify where they can store their
spreadsheets and use them at a later date.

For the initial pass we’re going to scope this to only allowing
spreadsheets with one column, ie just phone numbers/email addresses.
This is because:
- it minimises the amount of personal info we’re storing
- it reduces the chance of getting a placeholder error when you go to
  send the message, which is probably a high-stress situation where you
  might not be able to re-generate the file

The code for this is mostly copied from the existing upload CSV journey.
It’s quite duplicative, but that’s what I needed to do to get this out
quickly. There are opportunities for refactoring later.

Similarly, I would have liked to split this up into better commit
messages, but it really was a case of just bashing code out until it
worked 😳

This commit does not:
- implement the ‘view a contact list page’ (it just has a placeholder
  because the API isn’t ready at the moment)
- link to this page (because it’s not ready to use yet)

app/main/views/uploads.py

@@ -1,25 +1,38 @@
 import base64
+import itertools
 import json
 import urllib
 import uuid
 from io import BytesIO
+from zipfile import BadZipFile
 
 from flask import (
     abort,
     current_app,
+    flash,
     redirect,
     render_template,
     request,
     url_for,
 )
+from notifications_utils.columns import Columns
 from notifications_utils.pdf import pdf_page_count
+from notifications_utils.recipients import RecipientCSV
+from notifications_utils.sanitise_text import SanitiseASCII
 from PyPDF2.utils import PdfReadError
 from requests import RequestException
+from xlrd.biffh import XLRDError
+from xlrd.xldate import XLDateError
 
 from app import current_service, notification_api_client, service_api_client
 from app.extensions import antivirus_client
 from app.main import main
-from app.main.forms import LetterUploadPostageForm, PDFUploadForm
+from app.main.forms import CsvUploadForm, LetterUploadPostageForm, PDFUploadForm
+from app.s3_client.s3_csv_client import (
+    s3download,
+    s3upload,
+    set_metadata_on_csv_upload,
+)
 from app.s3_client.s3_letter_upload_client import (
     get_letter_metadata,
     get_letter_pdf_and_metadata,
@@ -28,10 +41,13 @@ from app.s3_client.s3_letter_upload_client import (
 )
 from app.template_previews import TemplatePreview, sanitise_letter
 from app.utils import (
+    Spreadsheet,
     generate_next_dict,
     generate_previous_dict,
+    get_errors_for_csv,
     get_letter_validation_error,
     get_template,
+    unicode_truncate,
     user_has_permissions,
 )
 
@@ -282,3 +298,144 @@ def send_uploaded_letter(service_id):
         service_id=service_id,
         notification_id=file_id,
     ))
+
+
+@main.route("/services/<uuid:service_id>/upload-a-contact-list", methods=['GET', 'POST'])
+@user_has_permissions('send_messages')
+def upload_contact_list(service_id):
+    form = CsvUploadForm()
+
+    if form.validate_on_submit():
+        try:
+            upload_id = s3upload(
+                service_id,
+                Spreadsheet.from_file(form.file.data, filename=form.file.data.filename).as_dict,
+                current_app.config['AWS_REGION'],
+            )
+            return redirect(url_for(
+                '.check_contact_list',
+                service_id=service_id,
+                upload_id=upload_id,
+                original_file_name=form.file.data.filename,
+            ))
+        except (UnicodeDecodeError, BadZipFile, XLRDError):
+            flash('Could not read {}. Try using a different file format.'.format(
+                form.file.data.filename
+            ))
+        except (XLDateError):
+            flash((
+                '{} contains numbers or dates that Notify cannot understand. '
+                'Try formatting all columns as ‘text’ or export your file as CSV.'
+            ).format(
+                form.file.data.filename
+            ))
+
+    return render_template(
+        'views/uploads/contact-list/upload.html',
+        form=form,
+    )
+
+
+@main.route(
+    "/services/<uuid:service_id>/check-contact-list/<uuid:upload_id>",
+    methods=['GET', 'POST'],
+)
+@user_has_permissions('send_messages')
+def check_contact_list(service_id, upload_id):
+
+    form = CsvUploadForm()
+
+    contents = s3download(service_id, upload_id).strip()
+    first_row = contents.splitlines()[0].strip().rstrip(',') if contents else ''
+
+    template_type = {
+        'emailaddress': 'email',
+        'phonenumber': 'sms',
+    }.get(Columns.make_key(first_row))
+
+    original_file_name = SanitiseASCII.encode(request.args.get('original_file_name', ''))
+
+    recipients = RecipientCSV(
+        contents,
+        template_type=template_type or 'sms',
+        whitelist=itertools.chain.from_iterable(
+            [user.name, user.mobile_number, user.email_address]
+            for user in current_service.active_users
+        ) if current_service.trial_mode else None,
+        international_sms=current_service.has_permission('international_sms'),
+        max_initial_rows_shown=50,
+        max_errors_shown=50,
+    )
+
+    non_empty_column_headers = list(filter(None, recipients.column_headers))
+
+    if len(non_empty_column_headers) > 1 or not template_type or not recipients:
+        return render_template(
+            'views/uploads/contact-list/too-many-columns.html',
+            recipients=recipients,
+            original_file_name=original_file_name,
+            template_type=template_type,
+            form=form,
+        )
+
+    if recipients.too_many_rows or not len(recipients):
+        return render_template(
+            'views/uploads/contact-list/column-errors.html',
+            recipients=recipients,
+            original_file_name=original_file_name,
+            form=form,
+        )
+
+    row_errors = get_errors_for_csv(recipients, template_type)
+    if row_errors:
+        return render_template(
+            'views/uploads/contact-list/row-errors.html',
+            recipients=recipients,
+            original_file_name=original_file_name,
+            row_errors=row_errors,
+            form=form,
+        )
+
+    if recipients.has_errors:
+        return render_template(
+            'views/uploads/contact-list/column-errors.html',
+            recipients=recipients,
+            original_file_name=original_file_name,
+            form=form,
+        )
+
+    metadata_kwargs = {
+        'row_count': len(recipients),
+        'valid': True,
+        'original_file_name': unicode_truncate(
+            original_file_name,
+            1600,
+        ),
+        'template_type': template_type
+    }
+
+    set_metadata_on_csv_upload(service_id, upload_id, **metadata_kwargs)
+
+    return render_template(
+        'views/uploads/contact-list/ok.html',
+        recipients=recipients,
+        original_file_name=original_file_name,
+        upload_id=upload_id,
+    )
+
+
+@main.route("/services/<uuid:service_id>/save-contact-list/<uuid:upload_id>", methods=['POST'])
+@user_has_permissions('send_messages')
+def save_contact_list(service_id, upload_id):
+    current_service.save_contact_list(upload_id)
+    return redirect(url_for(
+        '.contact_list',
+        service_id=current_service.id,
+        contact_list_id=upload_id,
+    ))
+
+
+@main.route("/services/<uuid:service_id>/contact-list/<uuid:contact_list_id>", methods=['GET'])
+@user_has_permissions('send_messages')
+def contact_list(service_id, contact_list_id):
+    return 'page for contact list {}'.format(contact_list_id)