Requirements

As listed by Platform Components, Cocov requires a few base components to be able to start:

PostgreSQL #

Cocov’s principal data storage facility is PostgreSQL, which is used solely by the API to store user data, repositories, commits, check results, coverage data, and statistics that are shown on the UI or returned through API endpoints.

Although where the database is host is not really important — minding the latency, — the user the API uses to connect to said database must have permission to create/update/delete tables (as required by Rails migration mechanism), and to create/read/update/delete data on those tables.

Redis #

Redis is heavily used for a few different activities required by almost all of Cocov’s components, such as:

• Inter-process communication
• Ephemeral data storage
• Cache
• Distributed locks
• Queues

Just like PostgreSQL, Cocov does not mind where your Redis instance is located, as long as it is able to quickly reply to components. The configuration documentation requires three different Redis URLs for different usages; those URLs may point to the same Redis instance, as long as they use different databases. We have successfully ran relatively large Cocov installations with a single Redis database without issues.

Data Storage #

Data storage is essential to Cocov’s runtime, as it clones and reads data from commits, meaning a reliable storage medium is of great importance. Additionally, such storage must also be able to accommodate concurrent accesses from more than one component, as API, Sidekiq, and the Worker may require data to be read/written to such storage.

Component	Read/Write?
API	Read/Write
Sidekiq	Read/Write
Worker	Read-Only

Additionally, extra storage may need to be provisioned if the instance being set up intends to leverage the Cache service to speedup checks.

When leveraging AWS S3 or Minio as a storage backend, make sure to allow both bucket and its objects to be accessible by Cocov. In terms of policy, the following actions should be permitted:

• s3:Put*
• s3:Get*
• s3:List*
• s3:Delete*

On both the bucket and its sub-resources. Given a bucket named foobar-cocov-storage, the following resources should be present in the policy statement:

• arn:aws:s3:::foobar-cocov-storage
• arn:aws:s3:::foobar-cocov-storage/*

Ingress/Egress #

Cocov requires requests from the internet to be able to reach the API, and the Badger if enabled, and to make external requests to a few different services.

The system makes requests to GitHub.com, Docker Hub, and may make arbitrary requests to download dependencies from projects being checked, tooling such as interpreters and/or compilers, and images for plugins being used by projects.