## `porter deploy`

> 🚧 Beta Notice
> 
> **Note:** `porter deploy` was introduced in version `0.4.0` and is currently in `beta`, thus it is subject to change and may not work reliably. If you encounter an error, please [file a bug report](https://github.com/porter-dev/porter/issues/new?assignees=&labels=&template=bug.md). 

Version `0.4.0` of Porter added supported for building and re-deploying an existing application using the Porter CLI. For example, the following command will re-deploy an application called `example-app` from the most recent Github commit in the specified branch/repository:

```sh
porter deploy --app example-app
```

The default behavior of `porter deploy` is to **use the remote repository as the source of truth**. If you would like to use a local directory (such as your current working directory) as the directory to build from, go to the [deploying from local source](#deploying-from-local-source) section.

By default, this command performs four steps: gets the environment variables for the application, builds a new Docker container from the source files, pushes a new Docker image to the remote registry, and calls the Porter webhook to re-deploy the application. However, we designed this command to be modular: if you would like to add intermediate steps in your own build process, you can call different `porter deploy` sub-commands separately:

- [`porter deploy get-env`](#porter-deploy-get-env) - prints the build environment variables to the terminal or a file.  
- [`porter deploy build`](#porter-deploy-build) - builds the Docker container used for deployment.
- [`porter deploy push`](#porter-deploy-push) - pushes the Docker container used for deployment to a remote registry.
- [`porter deploy call-webhook`](#porter-deploy-call-webhook) - calls the Porter webhook to trigger a re-deploy of the application. 

To see a working example, check out the [creating a custom CI pipeline]() guide.

### `porter deploy get-env`

Gets environment variables for a deployment for a specified application given by the `--app` flag. By default, env variables are printed via stdout for use in downstream commands:

```sh
porter deploy get-env --app example-app
```

Output can also be written to a dotenv file via the `--file` flag, which should specify the destination path for a `.env` file. For example:

```sh
porter deploy get-env --app example-app --file .env
```

### `porter deploy build`

Builds a new version of the application specified by the `--app` flag. Depending on the configured settings, this command may work automatically or will require a specified `--method` flag. 

If you have configured the Dockerfile path and/or a build context for this application, this command will by default use those settings, so you just need to specify the `--app` flag:

```sh
porter deploy build --app example-app
```

If you have not linked the build-time requirements for this application, the cloud-native buildpacks builder will automatically be run from the current directory. If you would like to change the build method, you can do so by using the `--method` flag, for example:

```sh
porter deploy build --app example-app --method docker
```

When using `--method docker`, you can specify the path to the Dockerfile using the `--dockerfile` flag. This will also override the Dockerfile path that you may have linked for the application:

```sh
porter deploy build --app example-app --method docker --dockerfile ./prod.Dockerfile
```

### `porter deploy push`

Pushes a new image for an application specified by the `--app` flag. This command uses the image repository saved in the application config by default. For example, if an application `nginx` was created from the image repo `gcr.io/snowflake-123456/nginx`, the following command would push the image `gcr.io/snowflake-123456/nginx:new-tag`:

```sh
porter deploy push --app nginx --tag new-tag
```

This command will not use your pre-saved authentication set up via `docker login`, so if you are using an image registry that was created outside of Porter, make sure that you have linked it via `porter connect`.

### `porter deploy call-webhook`

Calls the webhook for an application specified by the --app flag. This webhook will trigger a new deployment for the application, with the new image set. For example:

```sh
porter deploy call-webhook --app example-app
```

This command will by default call the webhook with image tag "latest," but you can specify a different tag with the --tag flag:

```sh
porter deploy call-webhook --app example-app --tag custom-tag
```

# Deploying from Local Source

You can choose to deploy from your local filesystem by using the `--local` flag:

```sh
porter deploy --app example-app --local
```

This will by default read from the directory that the `porter` command is called from. If you would like to specify a different directory, use the `--path` flag:

```sh
porter deploy --app example-app --local --path ~/porter/porter-example
```