Create an application accelerator

This is the first in a series of Getting started how-to guides for operators. It walks you through creating an application accelerator by using Tanzu Application Platform GUI and CLI.

For background information about application accelerators and for more advanced features like composition using fragments, see Application Accelerator.

What you will do

Select a Git repository to create your accelerator and clone the repository.
Create an accelerator.yaml file that defines your accelerator and commit it to your Git repository.
Publish your application accelerator and view it in Tanzu Application Platform GUI.
Begin to work with your accelerator.

Create an application accelerator

For this example, use a publicly accessible Git repository and include a README file in the repository. You can configure these options when you create a repository on GitHub. You need the repository URL to create an accelerator.

To create a new application accelerator by using your Git repository, follow these steps:

Clone your Git repository:

git clone https://github.com/path/to/repo

Create an empty file named accelerator.yaml in the root directory of this Git repository.

Add the following content to the accelerator.yaml file:

accelerator:
  displayName: Simple Accelerator
  description: Contains just a README
  iconUrl: https://images.freecreatives.com/wp-content/uploads/2015/05/smiley-559124_640.jpg
  tags:
  - simple
  - getting-started

You can use any icon that has a reachable URL.

Add the new accelerator.yaml file, commit this change, and push it to your Git repository.
```
git add accelerator.yaml
git commit -m "Creating accelerator.yaml"
git push
```

Publish the new accelerator

To publish the new application accelerator that is created in your Git repository, follow these steps:

Set up environment variables by running:
```
export GIT_REPOSITORY_URL=YOUR-GIT-REPOSITORY-URL
export GIT_BRANCH=YOUR-GIT-BRANCH
```
Where:
- YOUR-GIT-REPOSITORY-URL is the URL of your Git repository.
- YOUR-GIT-BRANCH is the name of the branch where you pushed the new accelerator.yaml file.
To publish the new application accelerator and name it simple, run:
```
tanzu accelerator create simple --git-repository ${GIT_REPOSITORY_URL} --git-branch ${GIT_BRANCH}
```
The accelerator name, simple, is used when updating accelerators as well, not the displayName parameter in the accelerator.yaml
Refresh Tanzu Application Platform GUI to reveal the newly published accelerator.

It might take a few seconds for Tanzu Application Platform GUI to refresh the catalog and add an entry for your new accelerator.

Working with accelerators

Updating an accelerator

After you push any changes to your Git repository, the accelerator is refreshed based on the git.interval setting for the Accelerator resource. The default value is 10 minutes. To force an immediate reconciliation, run:

tanzu accelerator update ACCELERATOR-NAME --reconcile

Where ACCELERATOR-NAME is the name of your accelerator.

Deleting an accelerator

When you no longer need your accelerator, you can delete it by using the Tanzu CLI:

tanzu accelerator delete ACCELERATOR-NAME

Using an accelerator manifest

You can also create a separate manifest file and apply it to the cluster by using the Tanzu CLI:

Create a simple-manifest.yaml file and add the following content:

apiVersion: accelerator.apps.tanzu.vmware.com/v1alpha1
kind: Accelerator
metadata:
  name: simple
  namespace: accelerator-system
spec:
  git:
    url: YOUR-GIT-REPOSITORY-URL
    ref:
      branch: YOUR-GIT-BRANCH

Where:

YOUR-GIT-REPOSITORY-URL is the URL of your Git repository.
YOUR-GIT-BRANCH is the name of the branch.

Apply the simple-manifest.yaml by running the following command in the directory where you created this file:
```
kubectl apply -f simple-manifest.yaml
```

Application Accelerator supports handling and management of accelerator manifests by using standard GitOps practices. For more information, see Configure Application Accelerator.

Next steps

Add testing and scanning to your application