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A library that allows your python tests to easily mock out the boto library

Project description

Moto - Mock AWS Services

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$ pip install moto[ec2,s3,all]

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(object):
    def __init__(self, name, value): = name
        self.value = value

    def save(self):
        s3 = boto3.client('s3', region_name='us-east-1')
        s3.put_object(Bucket='mybucket',, 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

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
    model_instance = MyModel('steve', 'is awesome')
    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.


The full documentation can be found here:

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