---
id: using-cloud-storage
title: Using Cloud Storage for TechDocs generated files
description: Using Cloud Storage for TechDocs generated files
---

In the [TechDocs architecture](./architecture.md) you have the option to choose
where you want to store the Generated static files which TechDocs uses to render
documentation. In both the "Basic" and "Recommended" setup, you can add cloud
storage providers like Google GCS, Amazon AWS S3, etc. By default, TechDocs uses
the local filesystem of the `techdocs-backend` plugin in the "Basic" setup. And
in the recommended setup, having one of the cloud storage is a prerequisite.
Read more on the TechDocs Architecture documentation page.

On this page you can read how to enable them.

## Configuring Google GCS Bucket with TechDocs

Follow the
[official Google Cloud documentation](https://googleapis.dev/nodejs/storage/latest/index.html#quickstart)
for the latest instructions on the following steps involving GCP.

**1. Set `techdocs.publisher.type` config in your `app-config.yaml`**

Set `techdocs.publisher.type` to `'googleGcs'`.

```yaml
techdocs:
  publisher:
    type: 'googleGcs'
```

**2. Create a GCS Bucket**

Create a dedicated Google Cloud Storage bucket for TechDocs sites.
techdocs-backend will publish documentation to this bucket. TechDocs will fetch
files from here to serve documentation in Backstage. Note that the bucket names
are globally unique.

Set the config `techdocs.publisher.googleGcs.bucketName` in your
`app-config.yaml` to the name of the bucket you just created.

```yaml
techdocs:
  publisher:
    type: 'googleGcs'
    googleGcs:
      bucketName: 'name-of-techdocs-storage-bucket'
```

**3a. (Recommended) Authentication using environment variable**

The GCS Node.js client will automatically use the environment variable
`GOOGLE_APPLICATION_CREDENTIALS` to authenticate with Google Cloud. It might
already be set in Compute Engine, Google Kubernetes Engine, etc. Read
https://cloud.google.com/docs/authentication/production for more details.

**3b. Authentication using app-config.yaml**

If you do not prefer (3a) and optionally like to use a service account, you can
follow these steps.

Create a new Service Account and a key associated with it. In roles of the
service account, use "Storage Admin".

If you want to create a custom role, make sure to include both `get` and
`create` permissions for both "Objects" and "Buckets". See
https://cloud.google.com/storage/docs/access-control/iam-permissions

A service account can have many keys. Open your newly created account's page (in
IAM & Admin console), and create a new key. Use JSON format for the key.

A `<GCP-PROJECT-ID-random-uid>.json` file will be downloaded. This is the secret
key TechDocs will use to make API calls. Make it available in your Backstage
server and/or your local development server and set it in the app config
`techdocs.publisher.googleGcs.credentials`.

```yaml
techdocs:
  publisher:
    type: 'googleGcs'
    googleGcs:
      bucketName: 'name-of-techdocs-storage-bucket'
      credentials:
        $file: '/path/to/google_application_credentials.json'
```

Note: If you are finding it difficult to make the file
`google_application_credentials.json` available on a server, you could use the
file's content and set as an environment variable. And then use

```yaml
techdocs:
  publisher:
    type: 'googleGcs'
    googleGcs:
      bucketName: 'name-of-techdocs-storage-bucket'
      credentials:
        $env: GOOGLE_APPLICATION_CREDENTIALS
```

**4. That's it!**

Your Backstage app is now ready to use Google Cloud Storage for TechDocs, to
store and read the static generated documentation files.

## Configuring AWS S3 Bucket with TechDocs

**1. Set `techdocs.publisher.type` config in your `app-config.yaml`**

Set `techdocs.publisher.type` to `'awsS3'`.

```yaml
techdocs:
  publisher:
    type: 'awsS3'
```

**2. Create an S3 Bucket**

Create a dedicated AWS S3 bucket for the storage of TechDocs sites.
[Refer to the official documentation](https://docs.aws.amazon.com/AmazonS3/latest/user-guide/create-bucket.html).

TechDocs will publish documentation to this bucket and will fetch files from
here to serve documentation in Backstage. Note that the bucket names are
globally unique.

Set the config `techdocs.publisher.awsS3.bucketName` in your `app-config.yaml`
to the name of the bucket you just created.

```yaml
techdocs:
  publisher:
    type: 'awsS3'
    awsS3:
      bucketName: 'name-of-techdocs-storage-bucket'
```

**3a. (Recommended) Setup authentication the AWS way, using environment
variables**

You should follow the
[AWS security best practices guide for authentication](https://docs.aws.amazon.com/general/latest/gr/aws-access-keys-best-practices.html).

If the environment variables

- `AWS_ACCESS_KEY_ID`
- `AWS_SECRET_ACCESS_KEY`
- `AWS_REGION`

are set and can be used to access the bucket you created in step 2, they will be
used by the AWS SDK v3 Node.js client for authentication.
[Refer to the official documentation.](https://docs.aws.amazon.com/sdk-for-javascript/v3/developer-guide/loading-node-credentials-environment.html)

If the environment variables are missing, the AWS SDK tries to read the
`~/.aws/credentials` file for credentials.
[Refer to the official documentation.](https://docs.aws.amazon.com/sdk-for-javascript/v3/developer-guide/loading-node-credentials-shared.html)

Note that the region of the bucket has to be set for the AWS SDK to work.
[See this](https://docs.aws.amazon.com/sdk-for-javascript/v3/developer-guide/setting-region.html).

**3b. Authentication using app-config.yaml**

AWS credentials and region can be provided to the AWS SDK via `app-config.yaml`.
If the configs below are present, they will be used over existing `AWS_*`
environment variables and the `~/.aws/credentials` config file.

```yaml
techdocs:
  publisher:
    type: 'awsS3'
    awsS3:
      bucketName: 'name-of-techdocs-storage-bucket'
      region:
        $env: AWS_REGION
      credentials:
        accessKeyId:
          $env: AWS_ACCESS_KEY_ID
        secretAccessKey:
          $env: AWS_SECRET_ACCESS_KEY
```

Refer to the
[official AWS documentation for obtaining the credentials](https://docs.aws.amazon.com/sdk-for-javascript/v3/developer-guide/getting-your-credentials.html).

Note: If you are using Amazon EC2 instance to deploy Backstage, you do not need
to obtain the access keys separately. They can be made available in the
environment automatically by defining appropriate IAM role with access to the
bucket. Read more
[here](https://docs.aws.amazon.com/general/latest/gr/aws-access-keys-best-practices.html#use-roles).

**4. That's it!**

Your Backstage app is now ready to use AWS S3 for TechDocs, to store and read
the static generated documentation files. When you start the backend of the app,
you should be able to see
`techdocs info Successfully connected to the AWS S3 bucket` in the logs.
