Initial commit, part 1

pkg/streamcontrol/config.go

@@ -0,0 +1,103 @@
+package streamctl
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/facebookincubator/go-belt/tool/logger"
+	"github.com/goccy/go-yaml"
+)
+
+type PlatformConfig[T any, S StreamProfile] struct {
+	Config         T
+	StreamProfiles map[string]S
+}
+
+type AbstractPlatformConfig = PlatformConfig[any, StreamProfile]
+
+type Config map[string]*AbstractPlatformConfig
+
+func (cfg *Config) UnmarshalYAML(b []byte) error {
+	t := map[string]*AbstractPlatformConfig{}
+	err := yaml.Unmarshal(b, &t)
+	if err != nil {
+		return fmt.Errorf("unable to unmarshal YAML of the root of the config: %w", err)
+	}
+
+	for k, v := range t {
+		b, err := yaml.Marshal(v.Config)
+		if err != nil {
+			return fmt.Errorf("unable to re-marshal YAML of config %#+v: %w", v, err)
+		}
+
+		vOrig, ok := (*cfg)[k]
+		if !ok {
+			continue
+		}
+
+		cfgCfg := vOrig.Config
+
+		err = yaml.Unmarshal(b, cfgCfg)
+		if err != nil {
+			return fmt.Errorf("unable to unmarshal YAML of platform-config %s: %w", b, err)
+		}
+		(*cfg)[k].Config = cfgCfg
+	}
+
+	for k := range *cfg {
+		_, ok := t[k]
+		if !ok {
+			delete(*cfg, k)
+		}
+	}
+
+	return nil
+}
+
+func GetPlatformConfig[T any, S any](ctx context.Context, cfg Config, id string) *PlatformConfig[T, S] {
+	platCfg, ok := cfg[id]
+	if !ok {
+		logger.Debugf(ctx, "config '%s' was not found in cfg: %#+v", id, cfg)
+		return nil
+	}
+	platCfgCfg, ok := platCfg.Config.(*T)
+	if !ok {
+		var zeroValue T
+		logger.Errorf(ctx, "unable to get the config: expected type '%T', but received type '%T'", zeroValue, platCfg.Config)
+		return nil
+	}
+	return &PlatformConfig[T, S]{
+		Config:         *platCfgCfg,
+		StreamProfiles: GetStreamProfiles[S](platCfg.StreamProfiles),
+	}
+}
+
+func GetStreamProfiles[S any](streamProfiles map[string]StreamProfile) map[string]S {
+	s := make(map[string]S, len(streamProfiles))
+	for k, pI := range streamProfiles {
+		p, ok := pI.(S)
+		if !ok {
+			var zeroS S
+			panic(fmt.Errorf("expected type %T, but received type %T", zeroS, pI))
+		}
+		s[k] = p
+	}
+	return s
+}
+
+func InitConfig[T any, S any](cfg Config, id string, platCfg PlatformConfig[T, S]) {
+	if _, ok := cfg[id]; ok {
+		panic(fmt.Errorf("id '%s' is already registered", id))
+	}
+	cfg[id] = &PlatformConfig[any, StreamProfile]{
+		Config: &platCfg.Config,
+	}
+}
+
+func ToAbstractStreamProfiles[S StreamProfile](in map[string]S) map[string]StreamProfile {
+	m := make(map[string]StreamProfile, len(in))
+	for k, v := range in {
+		m[k] = v
+	}
+	return m
+}