Moto - Mock AWS Services

Install

$ pip install moto-improved-cognitoidentity

In a nutshell

Moto is a library that allows your tests to easily mock out AWS Services.

Imagine you have the following python code that you want to test:

import boto3


class MyModel:
    def __init__(self, name, value):
        self.name = name
        self.value = value

    def save(self):
        s3 = boto3.client("s3", region_name="us-east-1")
        s3.put_object(Bucket="mybucket", Key=self.name, Body=self.value)

Take a minute to think how you would have tested that in the past.

Now see how you could test it with Moto:

import boto3
from moto import mock_s3
from mymodule import MyModel


@mock_s3
def test_my_model_save():
    conn = boto3.resource("s3", region_name="us-east-1")
    # We need to create the bucket since this is all in Moto's 'virtual' AWS account
    conn.create_bucket(Bucket="mybucket")
    model_instance = MyModel("steve", "is awesome")
    model_instance.save()
    body = conn.Object("mybucket", "steve").get()["Body"].read().decode("utf-8")
    assert body == "is awesome"

With the decorator wrapping the test, all the calls to s3 are automatically mocked out. The mock keeps the state of the buckets and keys.

For a full list of which services and features are covered, please see our implementation coverage.

Documentation

The full documentation can be found here:

http://docs.getmoto.org/en/latest/

Fork Feature

In the original Moto cognitoidentity's method get_id() creates new identifiers on the fly. Each time it's requested the library generates a new one. In cases when identity_id is used to associate it with the user this behavior makes it impossible to test. This version of library generates identifiers based on user's data and provides the same value each time the user requests it.