config

README

go-orb/config

Package go-orb/config is a pluggable config provider for loosely coupled components.

It provides 2 main functions

config.Read

Read reads urls into []source.Data where Data is basicaly map[string]any.

This is done over config/source.Plugins and currently there are 3 Plugins for config.source:

• cli provides config from cli/env sources.
• file provides config from file sources.
• http provides config from http sources.

It's straight forward to write Plugins for config.source and we will provide more:

• nats
• etcd
• consul

An example:

package main

import (
    "log"
    "net/url"

    "github.com/go-orb/config"
    _ "github.com/go-orb/config-plugins/marshaler/json"
    _ "github.com/go-orb/config-plugins/marshaler/yaml"
    _ "github.com/go-orb/config-plugins/source/file"
    _ "github.com/go-orb/config-plugins/source/http"
)

func main() {
    // https://raw.githubusercontent.com/go-orb/config-plugins/main/test/data/set1/registry1.yaml
    u1, err := url.Parse("./data/set1/registry1")
    if err != nil {
        log.Fatal(err)
    }

    u2, err := url.Parse("https://raw.githubusercontent.com/go-orb/config-plugins/main/test/data/set1/registry2.json")
    if err != nil {
        log.Fatal(err)
    }

    datas, err := config.Read([]*url.URL{u1, u2}, []string{"app"})
    if err != nil {
        log.Fatal(err)
    }
}

config.Parse

Parse parses the config from config.Read into the given struct.

Example:

    // extend the config.Read example here

    //
    // All from here is in the plugin itself.
    //
    cfg := newRegistryMdnsConfig()
    err := config.Parse([]string{"app", "registry"}, datas, cfg)
    if err != nil {
        log.Fatal(err)
    }

Authors

• Asim Aslam - Author of go-micro/config on which this is based on.
• David Brouwer - Ideas
• René Jochum - Developer

License

Orb is Apache 2.0 licensed.

Documentation

Overview

Package config provides config handling for orb.

Index

• Variables
• func Get[T any](data map[string]any, key string, def T) (T, error)
• func Parse(sections []string, configs []source.Data, target any) error
• func Read(urls []*url.URL, prependSections []string) ([]source.Data, error)

Variables

var (
	// ErrUnknownPlugin happens when there's no config factory for the given plugin.
	ErrUnknownPlugin = errors.New("unknown config given")

	// ErrNotExistent happens when a config key is not existent.
	ErrNotExistent = errors.New("no such config key")

	// ErrTypesDontMatch happens when types don't match during Get[T]().
	ErrTypesDontMatch = errors.New("config key requested type and actual type don't match")

	// ErrUnknownScheme happens when you didn't import the plugin for the scheme or the scheme is unknown.
	ErrUnknownScheme = errors.New("unknown config source scheme")

	// ErrNoSuchFile happens when theres no file.
	ErrNoSuchFile = errors.New("no such file or no marshaler found")
)

Functions

func Get

func Get[T any](data map[string]any, key string, def T) (T, error)

Get returns either the value of "key" in "data" or the default value "def". * If types don't match it returns ErrTypesDontMatch. * If key hasn't been found it returns ErrNotExistent as well as the default value "def". * * It supports the following datatypes: * - any non-container (string/float64/uvm.) * - []string slice * - []any slice * - map[string]string * - map[string]any * .

func Parse

func Parse(sections []string, configs []source.Data, target any) error

Parse parses the config from config.Read into the given struct.

func Read

func Read(urls []*url.URL, prependSections []string) ([]source.Data, error)

Read reads urls into []Data where Data is basically map[string]any.

By default it will error out if any of these config URL's fail, but you can ignore errors for a single url by adding "?ignore_error=true".

prependSections is for url's that don't support sections (cli for example), theier result will be prepended, also you can add sections to a single url with "?add_section=true".