# Modify, validate, and publish the data structure using Snowplow CLI
> Validate data structure schemas for errors and warnings, then publish to development and production environments using Snowplow CLI.
> Source: https://docs.snowplow.io/tutorials/data-structures-in-git/validation-and-publishing/
> Documentation index: https://docs.snowplow.io/llms.txt

Firstly we'll add a property to our data structure definition. We'd like to know if a login succeeded or failed. Our modified `login.yaml` should look like this

```yml
apiVersion: v1
resourceType: data-structure
meta:
  hidden: false
  schemaType: event
  customData: {}
data:
  $schema: http://iglucentral.com/schemas/com.snowplowanalytics.self-desc/schema/jsonschema/1-0-0#
  self:
    vendor: com.example
    name: login
    format: jsonschema
    version: 1-0-0
  type: object
  properties:
    result:
      enum: [success, failure]
  additionalProperties: false
```

## Validate

We should validate our changes before we attempt to publish them. Let's do that

```bash
$ snowplow-cli ds validate data-structures/com.example/login.yaml
```

> **Tip:** You can supply snowplow-cli with a directory and it will look for anything that looks like a data structure. Also given the default data structure directory is being used the previous command is equivalent to `snowplow-cli ds validate`.

You should see output similar to this:

```text
3:00PM INFO validating from paths=[data-structures/com.example/login.yaml]
3:00PM INFO will create file=data-structures/com.example/login.yaml vendor=com.example name=login version=1-0-0
3:00PM WARN validation file=data-structures/com.example/login.yaml
  messages=
  │ The schema is missing the "description" property (/properties/result)
  │ The schema is missing the "description" property (/)
```

## Publish to development

Apart from the missing descriptions everything looks good. We can fill them in later. Let's go ahead and publish our data structure to our [development](/docs/testing/) environment.

```bash
$ snowplow-cli ds publish dev
```

> **Tip:** We omit the directory here but as with other commands the default directory will get used and it will attempt to publish any data structures it can find.

The command should output something close to the following:

```text
3:00PM INFO publishing to dev from paths=[data-structures]
3:00PM INFO will create file=data-structures/com.example/login.yaml vendor=com.example name=login version=1-0-0
3:00PM WARN validation file=data-structures/com.example/login.yaml
  messages=
  │ The schema is missing the "description" property (/properties/result)
  │ The schema is missing the "description" property (/)
3:00PM INFO all done!
```

> **Note:** Publishing to `dev` will also run validation. It will only fail on ERROR notifications.

You should now be able to see your published data structure in [Console UI](https://console.snowplowanalytics.com/data-structures). If you click through from the data structure listing to view the `login` data structure you should see the following banner.

![Console UI banner on the login data structure page saying \"This data structure is locked because it is managed in an external repository and can\'t be edited from the console UI,\" with Unlock and Learn more options](/assets/images/locked-57bc4e2e7e71494600acaa1b219d5b2c.png)

Any data structures published using snowplow-cli will automatically get this banner and have UI based editing disabled. It is a good idea to settle on one source of truth for each data structure to avoid potential conflicts.

## Publish to production

With our data structure deployed to develop and working as we expect we can safely publish it to production.

```bash
$ snowplow-cli ds publish prod
```

```text
3:00PM INFO publishing to prod from paths=[data-structures]
3:00PM INFO will update file=data-structures/com.example/login.yaml local=1-0-0 remote=""
3:00PM INFO all done!
```

> **Note:** Data structures must be published to `dev` before they can be published to `prod`

We have now seen how to create, validate and then publish a new data structure from the command line. Next we'll look at how to configure github actions to run validation and publishing automatically for us.