Flask

The Flask integration adds support for the Flask Web Framework.

Install

Install sentry-sdk from PyPI with the flask extra:

pip install --upgrade "sentry-sdk[flask]"

Configure

If you have the flask package in your dependencies, the Flask integration will be enabled automatically when you initialize the Sentry SDK.

import sentry_sdk

sentry_sdk.init(
    dsn="https://examplePublicKey@o0.ingest.sentry.io/0",
    # Set traces_sample_rate to 1.0 to capture 100%
    # of transactions for tracing.
    traces_sample_rate=1.0,
    # Set profiles_sample_rate to 1.0 to profile 100%
    # of sampled transactions.
    # We recommend adjusting this value in production.
    profiles_sample_rate=1.0,
)

Verify

from flask import Flask

sentry_sdk.init(...)  # same as above

app = Flask(__name__)

@app.route("/")
def hello_world():
    1 / 0  # raises an error
    return "<p>Hello, World!</p>"

When you point your browser to http://localhost:5000/ a transaction in the Performance section of sentry.io will be created. Additionally, an error event will be sent to sentry.io and will be connected to the transaction.

It takes a couple of moments for the data to appear in sentry.io.

Behavior

After initialization:

• If you use flask-login and set send_default_pii=True in your call to init, user data (current user id, email address, username) will be attached to the event.
• Request data will be attached to all events: HTTP method, URL, headers, form data, JSON payloads. Sentry excludes raw bodies and multipart file uploads.
• Logs emitted by app.logger or any logger will be recorded as breadcrumbs by the Logging integration (this integration is enabled by default).

Options

If you add FlaskIntegration explicitly to your sentry_sdk.init() call you can set options for FlaskIntegration to change its behavior:

import sentry_sdk
from sentry_sdk.integrations.flask import FlaskIntegration

sentry_sdk.init(
    # ...
    integrations = [
        FlaskIntegration(
            transaction_style="url",
            http_methods_to_capture=("GET",),
        ),
    ],
)

You can pass the following keyword arguments to FlaskIntegration():

• transaction_style:

  Sets the format or style that transactions are named.

  
  
  Python

  Copied

  @app.route("/myurl/<foo>")
  def myendpoint():
      return "<p>Hello, World!</p>"
  

  In the above code, you would set the transaction to:

  • /myurl/<foo> if you set transaction_style="url".
  • myendpoint if you set transaction_style="endpoint".

  The default is "endpoint".

• http_methods_to_capture:

  A tuple containing all the HTTP methods that should create a transaction in Sentry.

  The default is ("CONNECT", "DELETE", "GET", "PATCH", "POST", "PUT", "TRACE",).

  (Note that OPTIONS and HEAD are missing by default.)

  Added in 2.15.0

  The http_methods_to_capture option.

Supported Versions

• Flask: 1.0+
• Python: 3.6+