Deployments

• stage of the software development lifecycle

• involves the process of making a software application or system available and operational on a specific environment or infrastructure.

• It typically includes tasks such as installing, configuring, and running the software on servers, cloud platforms, or other computing environments.

• Deployment focuses on the technical aspects of getting the software up and running.

• During deployment, developers and operations teams work together to ensure that the application is properly installed, the necessary dependencies are satisfied, and the system is ready to serve end users.

• Deployments can be performed multiple times during the development cycle, particularly during iterative development and continuous integration/continuous deployment (CI/CD) practices.

Stages

• Planning:

  • defining the deployment strategy, including determining the target environment, infrastructure requirements, and deployment timeline.

  • It may also involve coordinating with different teams, such as development, operations, and testing, to align on the deployment plan.

• Building and Packaging:

  • the software application is built, compiled, and packaged into a distributable format.

  • tasks such as code compilation, asset generation, and creating executable files or containers.

  • Can be done before deployment (ie as part of a CI)

• Configuration and Environment Setup:

  • The deployment environment, including servers, databases, networking, and other infrastructure components, is prepared and configured to support the software application.

  • includes setting up

    • appropriate configurations

    • installing dependencies

    • ensuring compatibility between the application and the environment

• Testing:

  • Can be optional, if done before

    • ie as part of CI, all parts are tested and an artifact is produced and versioned which will be the candidate to be deployed

  • Before deploying the software to production, it is crucial to perform testing to verify its functionality, performance, and stability.

  • This can involve various types of testing, such as unit testing, integration testing, regression testing, and user acceptance testing (UAT).

  • Testing helps identify and resolve any issues or bugs that may impact the deployment.

• Deployment Execution

  • involves actually deploying the software to the target environment.

  • Depending on the deployment strategy, this can be a manual or automated process.

    • Manual deployment may involve transferring files, running installation scripts, or configuring the software manually.

    • Automated deployment often utilizes tools and frameworks like CI/CD pipelines to streamline the process, ensuring consistency and reducing human error.

• Verification and Validation:

  • Once the software is deployed, it is important to validate that the deployment was successful and the application is functioning as expected.

  • This may involve performing

    • additional tests

    • monitoring system behavior

    • comparing the deployed version against predefined criteria or acceptance criteria.

    • runnign a smoke test (automated or manaul)

    • checking the status page is up and passing

    • checking logs are showing no errors

• Rollback and Recovery

  • In case any issues or unexpected problems arise during or after the deployment, having a rollback plan is important.

  • Rollback involves reverting to a previous version or configuration to mitigate the impact of a failed deployment.

  • Additionally, recovery plans should be in place to address any potential downtime, data loss, or service disruptions.

• Post-Deployment Activities

  • After the successful deployment, there are often additional tasks to perform,

  • updating documentation

  • notifying stakeholders about the new version

  • monitoring system performance

  • gathering feedback from end users

• These activities help ensure that the deployed software is well-maintained and any necessary improvements or bug fixes are addressed in subsequent releases.