Jinja2

01 Apr 2014 You need to add the following to your jinja2 template:
{{ request.path ~ '?' ~ request.query_string }}

You can also print only the Get Variables / URL Parameters / Argument String with the following:
print request.query_string

The example is available here: http://stackoverflow.com/a/11781872/1364191

SQLalchemy Cheat Sheet

28 Mar 2014 Common Filter Operators: http://manuelmax.tumblr.com/post/289720781/common-filter-operators-sqlalchemy

Common relationships: http://docs.sqlalchemy.org/en/latest/orm/relationships.html#basic-relational-patterns

If you're using Flask-SQLalchemy, their documentation serves as an awesome quick summary of how to use SQLalchemy: http://pythonhosted.org/Flask-SQLAlchemy/

Use A Temporary File (StringIO) for Pandas's to_csv - Python Flask

27 Mar 2014 This link helped me use a temporary file for an excel export in flask (using pandas): https://coderwall.com/p/nwbuhq

Get Column and Row Labels In selectHandler - Google Charts / Visualization API

27 Mar 2014 For a more complete example of using selectHandler, see this page: https://developers.google.com/chart/interactive/docs/basic_interactivity

My example below get the labels from the row and the columns. I used this to send the user to another link and drill-down.

// this is an example of a bar chart's selectHandler function
function selectHandler() {
var selection = chart.getSelection();
var item = selection[0];

if (item.row != null && item.column != null) {
var rowLabel = parseInt(data.getValue(item.row, 0));
var columnLabel = data.getColumnLabel(item.column);
}
}
google.visualization.events.addListener(chart, 'select', selectHandler);

Ordered Post Data - Python Requests

23 Mar 2014 Here's an example of how to send ordered data with python's Requests library, for when the order of your post request data matters:

import requests
from collections import OrderedDict

payload = OrderedDict([("username", "admin"), ("pwd", "password")]) # the order matters!
r = requests.post('http://1.1.1.1/example', data=payload)
print r.text

Example of custom filters - Flask-Admin

18 Mar 2014 Update: I got this example added to the project: https://github.com/mrjoes/flask-admin/tree/master/examples/custom-sqla-filter

This Github issue has an example of how to use custom filters in Flask-Admin: https://github.com/mrjoes/flask-admin/issues/400

Multiple Views Based On Same Model - Flask-Admin

17 Mar 2014 You need to manually change the endpoint like MrJoes says in issue 480: https://github.com/mrjoes/flask-admin/issues/480

Here's an example:
admin.add_view(MyModelView(model.CsvTable, db.session, endpoint="duplicate_view"))

You can now visit your view by going to 0.0.0.0/admin/duplicate_view

Checkmark "column_formatters" - Flask-Admin

04 Mar 2014 In your custom ModelView, you need to add the following lines:
from flask.ext.admin.model.template import macro
column_formatters = dict(your_column=macro('render_your_column'))
list_template = 'list.html'

In your custom list.html template, you need to add the following jinja2 code:
{% macro render_your_column(model, column) %}
{% if model.your_column%}<i class="icon-ok"></i>{% endif %}
{% endmacro %}

If your row has a value in "your_column", then it will show as a checkmark. You need to make a new macro for each column.

Flask-Migrate

04 Mar 2014 https://github.com/miguelgrinberg/Flask-Migrate

Flask-Migrate is exactly what I've been looking for when it comes to database migrations. When I create PHP applications with MVC frameworks, the changes in the database need to be done manually when the model is changed. Flask-Migrate handles changes to the database (like adding/removing columns) so your models reflect your database.

This is a big advantage Flask has over PHP frameworks.

Pip Not Working From Powershell

26 Feb 2014 If you have strawberry perl installed, you may get one of these errors when you try to use pip from powershell:

Did not provide a command
Unknown or unsupported command 'install'

This is the result of a conflict between strawberry perl's pip and python's pip. You need to remove anything related to strawberry perl from your path environmental variable and ensure you have C:\Python27\Scripts and C:\Python27\Scripts in your environmental variables.

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