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Dash testing dcc.upload with dash.testing

When writing production ready code we want to be able to automatically test our webapp everytime we update the code. Dash for python allows this through dash.testing. However in my app I upload an excel file utilizing the dcc.Upload() component.
How do I write a test that can send the upload link to this component?

The dcc.Upload component does not allow you to put an id on the that stores the upload link.
It is easy to work around this by inspecting the upload button/field that you have created with web developer tools. look for the line that contains "<input type=file ... >". in the elements tab.
Right click it and press copy xpath and it should give you a relative path like //*[#id="upload-data"]/div/input
The test case would look like this
from dash.testing.application_runners import import_app
def test_xxxx001_upload(dash_duo):
# get app from app.py
app = import_app("src.app")
dash_duo.start_server(app)
# find element that contains input link. Utilize the web driver to get the element
element = dash_duo.driver.find_element_by_xpath('//*[#id="upload-data"]/div/input')
element.send_keys("C:\\path\\to\\testData.xlsx")
folder structure
myapp
--src
--app.py
--server.py
--run.py
--tests
--test_app
the use of the dcc.Upload component to create an upload button
import dash_core_components as dcc
import dash_html_components as html
html.Div(
id="file-drop",
children=[
dcc.Upload(
id="upload-data",
children=html.Div(
["Drag and Drop or ", html.A("Select File"),],
id="select-file",
),
multiple=False,
),
html.Div(id="output-data-upload"),
],
)

Flask_Scss not compiling scss file in simple app

I'm trying to use Flask-Scss to compile a scss file in my flask app. Here is my app:
from flask import Flask, jsonify, render_template, request
from flask_scss import Scss
app = Flask(__name__)
app.debug = True
Scss(app, static_dir='static', asset_dir='assets/scss/')
#app.route('/')
def index():
return render_template('index.html')
if __name__ == '__main__':
app.run(debug=True)
This file is in a directory that also contains a static directory and assets directory. Furthermore, assets contains a scss directory, which holds the file test.scss. When I run the app, I don't see any css files getting created inside of static. Can someone please tell me what I'm doing wrong?

You have to put absolute path for it to work. Assuming your structure is app/init.py then this should be your code:
Scss(app, static_dir='app/static', asset_dir='app/assets/scss')
NOTE: Don't forget to reload the page for the compiling to happen. If you don't reload the page then scss files will not be compiled to css.

I recommend using libsass, it works for both Sass and SCSS files. After you import sass simply use the compile function with the dirname keyword argument, like this:
sass.compile(dirname=('path/to/source', 'path/to/target'))
You also have the option to set the output style, for example:
sass.compile(dirname=('path/to/source', 'path/to/target'), output_style='compressed')
If you want to watch a file or directory for automatic compilation on every edit use boussole.

Serve stylesheet with webapp2 outside of Google App Engine

So I have successfully deployed an app using webapp2/jinja2 and a Paste server, but am having trouble serving static stylesheets.
I have had luck accessing static files via this method, as well as implementing a StaticFileHandler I found with some google-fu:
import os
import mimetypes
import webapp2
import logging
class StaticFileHandler(webapp2.RequestHandler):
def get(self, path):
abs_path = os.path.abspath(os.path.join(self.app.config.get('webapp2_static.static_file_path', 'static'), path))
if os.path.isdir(abs_path) or abs_path.find(os.getcwd()) != 0:
self.response.set_status(403)
return
try:
f = open(abs_path, 'r')
self.response.headers.add_header('Content-Type', mimetypes.guess_type(abs_path)[0])
self.response.out.write(f.read())
f.close()
except:
self.response.set_status(404)
where my main app routing looks like:
app = webapp2.WSGIApplication([('/', HelloWorld),
(r'/display', DisplayHandler),
(r'/static/(.+)', StaticFileHandler)
], debug=True)
My css files are in a folder under the app root: /static/css/main.css
I can access the file via direct url, and even link it as a stylesheet, but the styles won't apply. Any ideas? Is there another way to serve stylesheets? Some way to implement an app.yaml similar to GAE?

you dont need a static file handler.
upload the app with the static file folder by adding this to your app.yaml
- url: /static/
static_dir: static
docs are here: https://developers.google.com/appengine/docs/python/config/appconfig#Static_Directory_Handlers
edit:
see answer below in comments

#Mnemon, hats off to you for solving my problem. I would upvote you but I'm not allowed to do that. You convinced me that if it's not the only webapp2 way without GAE, it's at least a way that will work.
But also I can contribute that your solution is now installable as "pip install webapp2_static", from pipi--- by an author who seems to be using his real name... you I'm sure. Other webapp2 docs that I found helpful are available here.
I'm implementing your code on a Linux desktop development server, using paste, which you also used:
def main():
from paste import httpserver
httpserver.serve(app, host='127.0.0.1', port='8080')
But with the code as you have it above (which appears to be utterly identical to that of webapp2_static.py file), I don't find that putting my css files in a folder named static in the app root works as you said.
For example, I have /home/user/proj/public_html/app/app.py, where the py file contains your code plus other "views" for my ultra-simple site. (I don't know how paste really works, so maybe for now the public_html is just in there for reference so that I don't become confused when I'm uploading stuff onto the production server.)
So if I put the css stylesheets into a folder named /static, then, if I put /static in as either a subdirectory of /app or of /public_html I find that neither location works; I must instead make it a subdirectory of /proj.
I wasn't expecting that, but the cure for me is to change the default 'static' in your app.configure.get(..., 'static') call, to 'public_html/app/static'. Then it works, with the /static folder inside /app.
Similarly using the pipi code with './app/static/ in place of the default 'static' doesn't work; I found that I need ./public_html/app/static instead (or maybe it was just /public_html/app/static or even public_html/app/static... I forgot... one of those worked).
I tested how your computation of abs_path works and have reworked it in the code below, in which I have junked your approach in favor of something more Djangoesque. To wit, in my one app py file I put at the top the following:
STATIC_DIR = os.sep + 'tostatic' + os.path.abspath(os.path.dirname(__file__)) + os.sep + 'static'
Then in the page to which I want to add css, my Home page in my case, I put a very readable:
<link href="{{STATIC_DIR}}/dist/css/bootstrap.min.css" rel="stylesheet" type="text/css">
For the "view" that generates my Home page I have (env is a jinja2 Environment object that takes a template loader as an argument):
class Home(webapp2.RequestHandler):
def get(self):
template = env.get_template('index.html')
template_values = {'STATIC_DIR': STATIC_DIR }
self.response.write(template.render(template_values))
And finally the URL routing is as in:
app = webapp2.WSGIApplication(
[
(r'/', Home),
(r'/tostatic/(.+)', StaticView),
], debug=True)
The view for the static file serving is now:
class StaticView(webapp2.RequestHandler):
def get(self, path):
path = os.sep + path
try:
f = open(path, 'r')
self.response.headers.add_header('Content-Type', mimetypes.guess_type(path)[0])
self.response.out.write(f.read())
f.close()
except Exception, e:
print 'Problem in StaticView:', e
self.response.set_status(404)
To finally close, the problem that I had with your approach is the one that I and other near noobs have with the departure of URLs from the legacy association with the file system. In your approach "static" is both a sub-directory and a string between slashes at the front of the URL that tells the interpreter which view (which webapp2.RequestHandler subclass) to run. You take the /static from the rest of the URL and then later hard-code it back on. And when it comes time to decide what to put in for href in the tag the HTML page coder has to remember that duplicity. With the {{STATIC_DIR}} template variable approach it's clear what to do. And it's easy to redefine the location of the static files--- only the STATIC_DIR declaration has to be changed.
I found that self.response.set_status(404) shows up in Firebug, but not Firefox. Evidently with webapp2 you must provide and serve your own HTTP status code pages.

self.response.headers.add_header('Content-Type', mimetypes.guess_type(abs_path)[0])
self.response.headers['Content-Type'] = mimetypes.guess_type(abs_path)[0]

How do I set up gaeunit 2.0a with my Django app?

I am trying to set up Google App Engine unit testing for my web application. I downloaded the file from here.
I followed the instructions in the readmen by copying the directory gaeunit into the directory with the rest of my apps and registering 'gaeunit' in settings.py. This didn't seem sufficient to actually get things going. I also stuck url('^test(.*)', include('gaeunit.urls')) into my urls.py file.
When I go to the url http://localhost:8000/test, I get the following error:
[Errno 2] No such file or directory: '../../gaeunit/test'
Any suggestions? I'm not sure what I've done wrong. Thanks!

You can copy url but in your urls.py include
(r'^test', include('gaeunit.urls')),
Also you will have to change test path in gaeunit.py
_LOCAL_DJANGO_TEST_DIR = 'test'
And in your main web test files under test folder include following line for django test setup
self.application = django.core.handlers.wsgi.WSGIHandler()

According to the instructions on the main page you should add the URL to app.yaml, not urls.py.
- url: /test.*
script: gaeunit.py

Read a file on App Engine with Python?

Is it possible to open a file on GAE just to read its contents and get the last modified tag?
I get a IOError: [Errno 13] file not accessible:
I know that i cannot delete or update but i believe reading should be possible
Has anyone faced a similar problem?
os.stat(f,'r').st_mtim

You've probably declared the file as static in app.yaml. Static files are not available to your application; if you need to serve them both as static files and read them as application files, you'll need to include 2 copies in your project (ideally using symlinks, so you don't actually have to maintain an actual copy.)
Update Nov 2014:
As suggested in the comments, you can now do this with the application_readable flag:
application_readable
Optional. By default, files declared in static file handlers are
uploaded as static data and are only served to end users, they cannot
be read by an application. If this field is set to true, the files are
also uploaded as code data so your application can read them. Both
uploads are charged against your code and static data storage resource
quotas.
See https://cloud.google.com/appengine/docs/python/config/appconfig#Static_Directory_Handlers

You can read files, but they're on Goooogle's wacky GAE filesystem so you have to use a relative path. I just whipped up a quick app with a main.py file and test.txt in the same folder. Don't forget the 'e' on st_mtime.
import os
from google.appengine.ext import webapp
from google.appengine.ext.webapp import util
class MainHandler(webapp.RequestHandler):
def get(self):
path = os.path.join(os.path.split(__file__)[0], 'test.txt')
self.response.out.write(os.stat(path).st_mtime)
def main():
application = webapp.WSGIApplication([('/', MainHandler)],
debug=True)
util.run_wsgi_app(application)
if __name__ == '__main__':
main()

+1 for the new "application_readable: true" feature. Before using this new feature I did run into an issue with GAEs' "wacky" file system while getting the NLP Montylingua to import.
Issue: Monty uses the open(filename,'rb') and a file pointer to file_ptr.read() in bytes from the static files. My implementation worked on my local windows system but failed upon deployment!
The fix: Specify the expected bytes to read file_ptr.read(4) #4 binary bytes
Appears to be something related to the 64 bit GAE server wanting to read in more (8 by default) bytes. Anyways, took a while to find that issue. Montylingua loads now.

I came up strange but working solution :) Jinja :)
Serving static files directly sometimes become a headache with GAE. Possible trade-off from performance let you move straigh forward with Jinja
- url: /posts/(.*\.(md|mdown|markdown))
mime_type: text/plain
static_files: static/posts/\1
upload: posts/(.*\.(md|mdown|markdown))
from jinja2 import Environment
from jinja2.loaders import FileSystemLoader
posts = Environment(loader=FileSystemLoader('static/posts/')) # Note that we use static_files folder defined in app.yaml
post = posts.get_template('2013-11-13.markdown')
import markdown2 # Does not need of course
class Main(webapp2.RequestHandler):
def get ( self ):
self.response.headers[ 'Content-Type' ] = 'text/html'
self.response.write ( markdown2.markdown( post.render()) ) # Jinja + Markdown Render function
Did you get it ;) I tested and It worked.

With webapp2, supposing you have pages/index.html at the same path as main.py:
#!/usr/bin/env python
import webapp2, os
class MainHandler(webapp2.RequestHandler):
def get(self):
path = os.path.join(os.path.split(__file__)[0], 'pages/index.html')
with open(path, 'r') as f:
page_content = f.read()
self.response.write(page_content)
app = webapp2.WSGIApplication([
('/', MainHandler)
], debug=True)

I can't see an answer for when the file hasn't been marked as static, and you're trying to read it in mode 'rt'; apparently that doesn't work. You can however open files just fine in mode 'rb', or just plain 'r'. (I wasted about 10 minutes on that 't'.)