JarCastingtest-operations
Overview
An Operation is an adaptation of the command pattern that knows how to revert executed commands, so that artifacts are not left behind after the test is complete.
For testing, this is a extremely useful pattern. This library provides a proven and tested framework to use as a base for writing integration tests in your projects.
Try it out
It's easy to get started adding operations to your Java project. Just add to your <dependencies> section:
<dependency>
<groupId>com.vmware.test-operations</groupId>
<artifactId>test-operations</artifactId>
<version>1.1.0</version>
<scope>test</scope>
</dependency>
Then implement your own class implementing an Operation. Examples are in the project.
Why do I want this?
Operations are a powerful pattern for building integration tests that need to clean up after themselves. They encourage well-written tests and have the following benefits:
Independent, reusable blocks
Operations encourage test functionality to be designed as a collection of reusable blocks. Each operation is responsible for implementing one specific behavior, usually around a complex behavior or an allocated resource. All of the code around creating, deleting, and validation of that resource is kept in a single object.
Test scenarios are then built up from these composable blocks, and then behavior is confirmed. Operations are also a convenient place for helper methods that perform additional verifications or extract information about the created resources.
Cleaning up
Operations, like Commands, encapsulate code that should be executed to create or reserve a resource.
Additionally they can "revert" the creation or reservation, to put the environment in the state it was before the test ran.
Once the tests are complete (successful or not), the operations need to clean up any allocated or reserved resources.
Operations treat this as a special mode, and ensure the following are true:
- cleanup is always run
- cleanup is best effort and resources may not be released (because of #1), and
- errors are suppressed (so as to not interfere with the actual test results)
Composable
Groups of operations can be treated as operations themselves.
The simplest composition is just a sequence of operations treated as a single operation. This is the mechanism commonly used in every test, so that after its execution, the combined sequence of operations is cleaned up in the opposite order.
But we can also group operations in a parallel list. Lists are executed concurrently (using a ExecutorService instance), which makes testing on multiple threads for concurrency extremely easy.
By combining the two, complex structures can be setup and torn down very quickly to decrease the running times of tricky integration tests. See OperationCollections for more details.
Built-in validation
Operations understand validations as a first-class helper object. By default, validations are run after the successful execution or reversion of an operation.
This encourages every operation to be validated in every test, without test writers having to duplicate basic validations and assertions.
For special situations, the validation list is mutable -- default validations can be removed and additional validations can be added easily.
Because validations are done separately, they are convenient when a single generic operation needs validation in different scenarios. An example would a generic "create" operation that needs to validate against both AWS and vSphere depending on the input. With validations, the operation code is shared, and the validation code can be specific.
For more details about the library and how to use it effectively, refer to DOCUMENTATION.md.
Contributing
The test-operations project team welcomes contributions from the community. If you wish to contribute code and you have not signed our contributor license agreement (CLA), our bot will update the issue when you open a Pull Request. For any questions about the CLA process, please refer to our FAQ. For more detailed information, refer to CONTRIBUTING.md.
License
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
