feat: proxy bootstrapping from configuration

internal/config/bootstrap.go

@@ -0,0 +1,104 @@
+package config
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"forge.cadoles.com/cadoles/bouncer/internal/store"
+	"github.com/pkg/errors"
+	"gopkg.in/yaml.v3"
+)
+
+type BootstrapConfig struct {
+	Proxies     map[store.ProxyName]BootstrapProxyConfig `yaml:"proxies"`
+	Dir         InterpolatedString                       `yaml:"dir"`
+	LockTimeout InterpolatedDuration                     `yaml:"lockTimeout"`
+}
+
+func (c *BootstrapConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	src := struct {
+		Proxies map[store.ProxyName]BootstrapProxyConfig `yaml:"proxies"`
+		Dir     InterpolatedString                       `yaml:"dir"`
+	}{
+		Proxies: make(map[store.ProxyName]BootstrapProxyConfig),
+		Dir:     "",
+	}
+
+	if err := unmarshal(&src); err != nil {
+		return errors.WithStack(err)
+	}
+
+	c.Proxies = src.Proxies
+	c.Dir = src.Dir
+
+	if src.Dir != "" {
+		proxies, err := loadBootstrapDir(string(src.Dir))
+		if err != nil {
+			return errors.Wrapf(err, "could not load bootstrap dir '%s'", src.Dir)
+		}
+
+		c.Proxies = overrideProxies(c.Proxies, proxies)
+	}
+
+	return nil
+}
+
+type BootstrapProxyConfig struct {
+	Enabled InterpolatedBool                         `yaml:"enabled"`
+	Weight  InterpolatedInt                          `yaml:"weight"`
+	To      InterpolatedString                       `yaml:"to"`
+	From    InterpolatedStringSlice                  `yaml:"from"`
+	Layers  map[store.LayerName]BootstrapLayerConfig `yaml:"layers"`
+}
+
+type BootstrapLayerConfig struct {
+	Enabled InterpolatedBool   `yaml:"enabled"`
+	Type    InterpolatedString `yaml:"type"`
+	Weight  InterpolatedInt    `yaml:"weight"`
+	Options InterpolatedMap    `yaml:"options"`
+}
+
+func NewDefaultBootstrapConfig() BootstrapConfig {
+	return BootstrapConfig{
+		Dir:         "",
+		LockTimeout: *NewInterpolatedDuration(30 * time.Second),
+	}
+}
+
+func loadBootstrapDir(dir string) (map[store.ProxyName]BootstrapProxyConfig, error) {
+	pattern := filepath.Join(dir, "*.yml")
+
+	files, err := filepath.Glob(pattern)
+	if err != nil {
+		return nil, errors.WithStack(err)
+	}
+
+	proxies := make(map[store.ProxyName]BootstrapProxyConfig)
+	for _, f := range files {
+		data, err := os.ReadFile(f)
+		if err != nil {
+			return nil, errors.Wrapf(err, "could not read file '%s'", f)
+		}
+
+		proxy := BootstrapProxyConfig{}
+
+		if err := yaml.Unmarshal(data, &proxy); err != nil {
+			return nil, errors.Wrapf(err, "could not unmarshal proxy")
+		}
+
+		name := store.ProxyName(strings.TrimSuffix(filepath.Base(f), filepath.Ext(f)))
+		proxies[name] = proxy
+	}
+
+	return proxies, nil
+}
+
+func overrideProxies(base map[store.ProxyName]BootstrapProxyConfig, proxies map[store.ProxyName]BootstrapProxyConfig) map[store.ProxyName]BootstrapProxyConfig {
+	for name, proxy := range proxies {
+		base[name] = proxy
+	}
+
+	return base
+}

internal/config/config.go

@@ -2,7 +2,7 @@ package config
 
 import (
 	"io"
-	"io/ioutil"
+	"os"
 
 	"github.com/pkg/errors"
 	"gopkg.in/yaml.v3"
@@ -10,18 +10,19 @@ import (
 
 // Config definition
 type Config struct {
-	Admin  AdminServerConfig `yaml:"admin"`
-	Proxy  ProxyServerConfig `yaml:"proxy"`
-	Redis  RedisConfig       `yaml:"redis"`
-	Logger LoggerConfig      `yaml:"logger"`
-	Layers LayersConfig      `yaml:"layers"`
+	Admin     AdminServerConfig `yaml:"admin"`
+	Proxy     ProxyServerConfig `yaml:"proxy"`
+	Redis     RedisConfig       `yaml:"redis"`
+	Logger    LoggerConfig      `yaml:"logger"`
+	Layers    LayersConfig      `yaml:"layers"`
+	Bootstrap BootstrapConfig   `yaml:"bootstrap"`
 }
 
 // NewFromFile retrieves the configuration from the given file
 func NewFromFile(path string) (*Config, error) {
 	config := NewDefault()
 
-	data, err := ioutil.ReadFile(path)
+	data, err := os.ReadFile(path)
 	if err != nil {
 		return nil, errors.Wrapf(err, "could not read file '%s'", path)
 	}
@@ -43,11 +44,12 @@ func NewDumpDefault() *Config {
 // NewDefault return new default configuration
 func NewDefault() *Config {
 	return &Config{
-		Admin:  NewDefaultAdminServerConfig(),
-		Proxy:  NewDefaultProxyServerConfig(),
-		Logger: NewDefaultLoggerConfig(),
-		Redis:  NewDefaultRedisConfig(),
-		Layers: NewDefaultLayersConfig(),
+		Admin:     NewDefaultAdminServerConfig(),
+		Proxy:     NewDefaultProxyServerConfig(),
+		Logger:    NewDefaultLoggerConfig(),
+		Redis:     NewDefaultRedisConfig(),
+		Layers:    NewDefaultLayersConfig(),
+		Bootstrap: NewDefaultBootstrapConfig(),
 	}
 }