README
¶
bedrock
bedrock provides a minimal, modular and composable foundation for quickly developing more use case specific frameworks in Go.
Building custom frameworks with bedrock
One of the guiding principals for bedrock is to be composable. This principal comes from the experience gained from working with custom, tailor made frameworks which over their lifetime within an organization are unable to adapt to changing development and deployment patterns. Eventually, these frameworks are abandoned for new ones or completely rewritten to reflect the current state of the organization.
bedrock defines a small set of types and carefully chooses its opinions to balance composability and functionality, as much as it can. The result is, in fact, a framework that isn't necessarily designed for building services directly, but instead meant for building more custom, use case specific frameworks.
For example, bedrock could be used by your organizations platform engineering or framework team(s) to quickly develop internal frameworks which abstract over all of your organizations requirements e.g. OpenTelemetry, Logging, Authenticated endpoints, etc. Then, due to the high composibility of bedrock, any changes within your organization would then be very easy to adapt to within your internal framework.
Core Concepts
type App interface {
Run(context.Context) error
}
App is a simple abstraction over the execution of your specific application type e.g. HTTP server, gRPC server, etc.
type AppBuilder[T any] interface {
Build(ctx context.Context, cfg T) (App, error)
}
AppBuilder puts the responsibility of App initialization in your hands!
The generic parameter provided to your AppBuilder is, in fact, your custom configuration type, which means no messing with config parsing and unmarshalling yourself!
package config
type Source interface {
Apply(Store) error
}
The config.Source is arguably the most powerful abstraction defined in any of the bedrock packages. It abstracts over the entire mechanic of sourcing your application configuration. This simple interface can then be implemented in various ways to support loading configuration from different files (e.g. YAML, JSON, TOML) to remote configuration stores (e.g. etcd).
func Run[T any](ctx context.Context, builder AppBuilder[T], srcs ...config.Source) error
The final piece and most crucial piece bedrock provides is the Run function which handles the orchestration of config parsing, app building and, lastly, app execution by relying on the other core abstractions noted above.
Putting them altogether
Below is a tiny and simplistic example of all the core concepts of bedrock.
config.yaml
logging:
min_level: {{env "MIN_LOG_LEVEL"}}
main.go
package main
import (
"bytes"
"context"
_ "embed"
"log/slog"
"os"
"github.com/z5labs/bedrock"
"github.com/z5labs/bedrock/app"
"github.com/z5labs/bedrock/appbuilder"
"github.com/z5labs/bedrock/config"
)
//go:embed config.yaml
var configBytes []byte
func main() {
os.Exit(run())
}
func run() int {
// bedrock does not handle process exiting for you. This is mostly
// to aid framework developers in unit testing their usages of bedrock
// by validating the returned error.
err := bedrock.Run(
context.Background(),
appbuilder.Recover(
bedrock.AppBuilderFunc[myConfig](initApp),
),
config.FromYaml(
config.RenderTextTemplate(
bytes.NewReader(configBytes),
config.TemplateFunc("env", os.Getenv),
),
),
)
if err == nil {
return 0
}
return 1
}
// myConfig can contain anything you like. The only thing you must
// remember is to always use the tag name, "config". If that tag
// name is not used then the bedrock config package will not know
// how to properly unmarshal the config source(s) into your custom
// config struct.
type myConfig struct {
Logging struct {
MinLevel slog.Level `config:"min_level"`
} `config:"logging"`
}
type myApp struct {
log *slog.Logger
}
// initApp is a function implementation of the bedrock.AppBuilder interface.
func initApp(ctx context.Context, cfg myConfig) (bedrock.App, error) {
var base bedrock.App = &myApp{
log: slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{
Level: cfg.Logging.MinLevel,
})),
}
base = app.Recover(base)
return base, nil
}
// Run implements the bedrock.App interface.
func (a *myApp) Run(ctx context.Context) error {
// Do something here like:
// - run an HTTP server
// - start the AWS lambda runtime,
// - run goroutines to consume from Kafka
// etc.
a.log.InfoContext(ctx, "running my app")
return nil
}
Built with bedrock
Documentation
¶
Overview ¶
Package bedrock provides a minimal foundation for building more complex frameworks on top of.
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func Recover ¶ added in v0.10.0
func Recover(err *error)
Recover calls [recover] and if a value is captured it will be wrapped into a PanicError. The PanicError will then be joined with any value, err, may reference. The joining is performed using errors.Join.
func Run ¶ added in v0.6.0
Run executes the application. It's responsible for reading the provided config sources, unmarshalling them into the generic config type, using the config and builder to build the users App and, lastly, running the returned App.
Example ¶
package main
import (
"context"
"fmt"
"strings"
"github.com/z5labs/bedrock/config"
)
type appFunc func(context.Context) error
func (f appFunc) Run(ctx context.Context) error {
return f(ctx)
}
func main() {
r := strings.NewReader(`hello: world`)
// Define a custom config struct which aligns with your
// the format of your config.Source(s).
type MyConfig struct {
Hello string `config:"hello"`
}
// Define a AppBuilder.
builder := AppBuilderFunc[MyConfig](func(ctx context.Context, cfg MyConfig) (App, error) {
// Inside your AppBuilder.Build is where you should be initializing
// all dependencies of your code e.g. backend API clients, DB connections, etc.
// Lastly, initialize something which implements the bedrock.App interface.
app := appFunc(func(c context.Context) error {
fmt.Println("hello,", cfg.Hello)
return nil
})
return app, nil
})
err := Run(context.Background(), builder, config.FromYaml(r))
if err != nil {
fmt.Println(err)
return
}
}
Output: hello, world
Types ¶
type AppBuildError ¶ added in v0.6.0
type AppBuildError struct {
Cause error
}
AppBuildError
func (AppBuildError) Error ¶ added in v0.6.0
func (e AppBuildError) Error() string
Error implements the [builtin.error] interface.
type AppBuilder ¶ added in v0.6.0
AppBuilder represents anything which can initialize a Runtime.
type AppBuilderFunc ¶ added in v0.6.0
AppBuilderFunc is a functional implementation of the AppBuilder interface.
type AppRunError ¶ added in v0.6.0
type AppRunError struct {
Cause error
}
AppRunError
func (AppRunError) Error ¶ added in v0.6.0
func (e AppRunError) Error() string
Error implements the [builtin.error] interface.
type ConfigReadError ¶ added in v0.6.0
type ConfigReadError struct {
Cause error
}
ConfigReadError
func (ConfigReadError) Error ¶ added in v0.6.0
func (e ConfigReadError) Error() string
Error implements the [builtin.error] interface.
type ConfigUnmarshalError ¶ added in v0.6.0
type ConfigUnmarshalError struct {
Cause error
}
ConfigUnmarshalError
func (ConfigUnmarshalError) Error ¶ added in v0.6.0
func (e ConfigUnmarshalError) Error() string
Error implements the [builtin.error] interface.
type PanicError ¶ added in v0.10.0
type PanicError struct {
Value any
}
PanicError represents a value that was recovered from a panic.
func (PanicError) Error ¶ added in v0.10.0
func (e PanicError) Error() string
Error implements the [error] interface.
func (PanicError) Unwrap ¶ added in v0.10.0
func (e PanicError) Unwrap() error
Unwrap implements the interface used by errors.Unwrap, errors.Is and errors.As.
Source Files
Directories
¶
| Path | Synopsis |
|---|---|
|
Package app provides helpers for common bedrock.App implementation patterns.
|
Package app provides helpers for common bedrock.App implementation patterns. |
|
Package appbuilder provides helpers for common bedrock.AppBuilder implementation patterns.
|
Package appbuilder provides helpers for common bedrock.AppBuilder implementation patterns. |
|
circuit
module
|
|
|
Package config provides very easy to use and extensible configuration management capabilities.
|
Package config provides very easy to use and extensible configuration management capabilities. |
|
key
Package key provides types for strongly typed keys in key value pairs.
|
Package key provides types for strongly typed keys in key value pairs. |
|
fit
module
|
|
|
host
module
|
|
|
internal
|
|
|
retry
module
|