Once the Instana python package is installed and available to the Python application, it can be actived via environment variable (without any code changes) or done manually. See below for details.

To install the Python sensor:

pip install instana

or to alternatively update an existing installation:

pip install -U instana

The Instana package sensor can be enabled without any code modifications required. To do this, install the package and set the following environment variable for your Python application:

AUTOWRAPT_BOOTSTRAP=instana

This will cause the Instana Python package to automatically instrument your Python application. Once it finds the Instana host agent, it will begin to report Python metrics.

In any Python 2.7 or greater application, to manually enable the Instana sensor, simply import the package:

import instana

To enable the Flask instrumentation, set the following environment variable in your application boot environment and then restart your application:

export AUTOWRAPT_BOOTSTRAP=flask

The Instana sensor includes WSGI middleware that can be added to any WSGI compliant stack. This is automated for various stacks but can also be done manually for those we haven't added support for yet.

The general usage is:

import instana
from instana.wsgi import iWSGIMiddleware

# Wrap the wsgi app in Instana middleware (iWSGIMiddleware)
wsgiapp = iWSGIMiddleware(MyWSGIApplication())

We are working to automate this for all major frameworks but in the meantime, here are some specific quick starts for those we don't have automatic support for yet.

import cherrypy
import instana
from instana.wsgi import iWSGIMiddleware

# My CherryPy application
class Root(object):
    @cherrypy.expose
    def index(self):
        return "hello world"

cherrypy.config.update({'engine.autoreload.on': False})
cherrypy.server.unsubscribe()
cherrypy.engine.start()

# Wrap the wsgi app in Instana middleware (iWSGIMiddleware)
wsgiapp = iWSGIMiddleware(cherrypy.tree.mount(Root()))

In this example, we use uwsgi as the webserver and booted with:

uwsgi --socket 127.0.0.1:8080 --protocol=http --wsgi-file mycherry.py --callable wsgiapp -H ~/.local/share/virtualenvs/cherrypyapp-C1BUba0z

Where ~/.local/share/virtualenvs/cherrypyapp-C1BUba0z is the path to my local virtualenv from pipenv

tldr; Make sure enable-threads and lazy-apps is enabled for uwsgi.

This Python instrumentation spawns a lightweight background thread to periodically collect and report process metrics. By default, the GIL and threading is disabled under uWSGI. If you wish to instrument your application running under uWSGI, make sure that you enable threads by passing --enable-threads (or enable-threads = true in ini style). More details in the uWSGI documentation.

If you use uWSGI in forking workers mode, you must specify --lazy-apps (or lazy-apps = true in ini style) to load the application in the worker instead of the master process.

uwsgi --socket 0.0.0.0:5000 --protocol=http -w wsgi -p 4 --enable-threads --lazy-apps

[uwsgi]
http = :5000
master = true
processes = 4
enable-threads = true # required
lazy-apps = true # if using "processes", set lazy-apps to true

# Set the Instana sensor environment variable here
env = AUTOWRAPT_BOOTSTRAP=flask

Instana provides deep end user monitoring that links server side traces with browser events to give you a complete view from server to browser.

For Python templates and views, get your EUM API key from your Instana dashboard and you can call instana.helpers.eum_snippet(api_key='abc') from within your layout file. This will output a small javascript snippet of code to instrument browser events. It's based on Weasel. Check it out.

As an example, you could do the following:

from instana.helpers import eum_snippet

instana.api_key = 'abc'
meta_kvs = { 'username': user.name }

# This will return a string containing the EUM javascript for the layout or view.
eum_snippet(meta=meta_kvs)

The optional second argument to eum_snippet() is a hash of metadata key/values that will be reported along with the browser instrumentation.

See also the End User Monitoring in the Instana documentation portal.