On [GOV.UK PaaS](https://www.cloud.service.gov.uk/), service credentials are appended to the environment variable `VCAP_SERVICES` when services [are bound](https://docs.cloud.service.gov.uk/deploying_services/s3/#bind-an-aws-s3-bucket-to-your-app) to an application.
Such services include datastores and S3 buckets.
Our application uses S3 and Redis clients and supports two different ways of parsing their configuration:
* Via the environment variable `VCAP_SERVICES` using the `PaasConfigurationService` class
* Via the environment variables `S3_CONFIG` and `REDIS_CONFIG` using the `EnvConfigurationService` class
`S3_CONFIG` and `REDIS_CONFIG` are populated using a similar structure than `VCAP_SERVICES`:
S3_CONFIG:
```json
[
{
"instance_name": "bucket_1",
"credentials": {
"aws_access_key_id": "123",
"aws_secret_access_key": "456",
"aws_region": "eu-west-1",
"bucket_name": "my-bucket"
}
}
]
```
REDIS_CONFIG:
```json
[
{
"instance_name": "redis_1",
"credentials": {
"uri": "redis_uri"
}
}
]
```
In order to switch from using [GOV.UK PaaS](https://www.cloud.service.gov.uk/) provided services to external ones, instances of `PaasConfigurationService` need to be replaced by `EnvConfigurationService`.
This assumes that `S3_CONFIG` or/and `REDIS_CONFIG` are available.
Please check `full_import.rake` and `rack_attack.rb` for examples of how the configuration is used.
The application is set up so that it can be deployed via GitHub actions. We use Git tags to mark releases. The only pre-requisite is that your GitHub account is added to our team.
To deploy you need to:
1. Determine [previous version](https://github.com/communitiesuk/submit-social-housing-lettings-and-sales-data/tags), such as `v0.1.1`.
2. Create a [new release](https://github.com/communitiesuk/submit-social-housing-lettings-and-sales-data/releases/new) with subsequent version (e.g., `v0.1.2`). On this page, create a new tag with that version and generate release notes. Save as draft.
3. Post release notes on Slack.
4. Publish release.
5. Monitor alerting, logging and Sentry.
6. Post success message on Slack.
7. Tag tickets as ‘Released’ and move tickets to done on JIRA.
## Deployment (Manual)
It is unlikely you will need to deploy manually as the GitHub actions method supersedes this one. This application is running on [GOV.UK PaaS](https://www.cloud.service.gov.uk/). To deploy you need to:
A failed Github deployment action will occasionally leave a Cloud Foundry deployment in a broken state. As a result all subsequent Github deployment actions will also fail with the message `Cannot update this process while a deployment is in flight`.
When a pull request is opened a review app will be spun up. The reviews apps connect to their own PostgreSQL and Redis instances with its own worker.
The review app github pipeline is independent of any test pipeline and therefore it will attempt to deploy regardless of the state the code is in.
The usual seeding process takes place when the review app boots so there will be some minimal data that can be used to login with. 2FA has been disabled in the review apps for easier access.
The app boots in a new environment called `review`. As such this is the environment you should filter by for sentry errors or to change any config.
After a sucessful deployment a comment will be added to the pull request with the URL to the review app for your convenience. When a pull request is updated e.g. more code is added it will re-deploy the new code.
Once a pull request has been closed the review app infrastructure will be tore down to save on any costs. Should you wish to re-open a closed pull request the review app will be spun up again.
One reason a review app deployment might fail is that it is attempting to run migrations which conflict with data in the database. For example you might have introduced a unique constraint, but the database associated with the review app has duplicate data in it that would violate this constraint, and so the migration cannot be run. There are two main ways to remedy this:
**Method 1 - Edit database via console**
1. Log in to Cloud Foundry
```bash
cf login -a api.london.cloud.service.gov.uk -u <your_username>
```
* Your username should be the email address you signed up to GOVUK PaaS with.
* Choose the dev environment whilst logging in.
2. If you were already logged in then Cloud Foundry, then instead just target the dev environment
```bash
cf target -o dluhc-core -s dev
```
3. Find the name of your app
```bash
cf apps
```
* The app name will be in this format: `dluhc-core-review-<pull-request-number>`.
