Bolt provides a concept of services as a declarative way of defining what resources are required. Services aren't always a unit of code; they can also be databases that need to provisioned or libraries used by other services.
See lib/bolt/config/src/service.rs to jump straight to the source.
Simple request/response functions. If an operation fails, it will return the error. (See GlobalError.)
These should be used for anything that reads from a database. Anything that's purely logic should be under the
util library.
Operations are exposed as Rust libraries. They are called using the op! macro. Under the hood, these are
simple function calls, but are abstracted so they can be separate processes communicated using RPC if needed.
Similar to operations, but reads from a durable stream and has no response. If a consumer fails, it will be retried indefinitely.
These should be used for anything that writes to a database.
Consumers are exposed as Rust libraries and are ran in the monolith-worker service. Messages can be
published using the msg! macro.
Hosts API endpoints for communication with the outside world.
These should only call operations & publish messages. These should not contain any communication with the database.
APIs are Rust binaries and ran as Kubernetes deployments with an exposed network interface. APIs can be configured with routes to automatically be exposed publicly using Traefik.
API routes are exposed as a library. These are imported by API services to expose publicly.
Headless services are Rust binaries and ran as Kubernetes deployments. They're called "headless" because they have no exposed network ports.
Useful for supporting infrastructure (such as log shipping) or adapting incoming data for Chirp services (such as consuming Nomad events).
Services that run once and only once. Useful for complex migrations.
Oneshot services are Rust binaries and ran as Kubernetes jobs.
Rust binaries deployed as a Kubernetes CRON job.
Creates a CockroachDB database. Contains migrations for this database that are automatically ran on
bolt db migrate up. See bolt db --help for more information.
A Redis cache.
Redis databases are split between two clusters: a persistent database (with AOF persistence, no eviction) and an ephemeral database (with LRU eviction).
There is no isolation between Redis services at the moment. This will change in the future with Redis ACL support.