Installation

$ pip install flask-codemirror

Example

A simple example of how to use this module

from flask_wtf import FlaskForm
from flask_codemirror.fields import CodeMirrorField
from wtforms.fields import SubmitField

class MyForm(FlaskForm):
    source_code = CodeMirrorField(language='python', config={'lineNumbers': 'true'})
    submit = SubmitField('Submit')

The CodeMirrorField works exactly like a TextAreaField

@app.route('/', methods = ['GET', 'POST'])
def index():
    form = MyForm()
    if form.validate_on_submit():
        text = form.source_code.data
    return render_template('index.html', form=form)

The module needs to be initialized in the usual way and can be configured using app.config keys

from flask import Flask
from flask_codemirror import CodeMirror
# mandatory
CODEMIRROR_LANGUAGES = ['python', 'yaml', 'htmlembedded']
WTF_CSRF_ENABLED = True
SECRET_KEY = 'secret'
# optional
CODEMIRROR_THEME = '3024-day'
CODEMIRROR_ADDONS = (
        ('ADDON_DIR','ADDON_NAME'),
)
app = Flask(__name__)
app.config.from_object(__name__)
codemirror = CodeMirror(app)

The config CODEMIRROR_LANGUAGES needs to be initialized to load JavaScript. It defined all the languages you want to edit with your fields. The config CODEMIRROR_THEME is optional and is used to style your TextArea using css from CodeMirror website. The config CODEMIRROR_ADDONS is optional and can enable many cool options see Codemirror Addons for available addons.

Finally, the template needs the support JavaScript code added, by calling codemirror.include_codemirror() :

<html>
  <head>
    {{ codemirror.include_codemirror() }}
  </head>
  <body>
    <form method="POST">
       {{ form.csrf_token }}
       {{ form.source_code }}
       <input type="submit" value="OK">
    </form>
  </body>
</html>

The Javascript classes are imported from a CDN, there are no static files that need to be served by the application.