rules: add manager set

Author: ellemouton

rules/manager_set.go

@@ -0,0 +1,86 @@
+package rules
+
+import (
+	"encoding/json"
+	"fmt"
+
+	"github.com/lightninglabs/lightning-terminal/litrpc"
+)
+
+// ErrUnknownRule indicates that LiT is unaware of a values name.
+var ErrUnknownRule = fmt.Errorf("unknown rule")
+
+// ManagerSet is a map from a rule name to a rule Manager.
+type ManagerSet map[string]Manager
+
+// NewRuleManagerSet creates a new map of the supported rule ManagerSet.
+func NewRuleManagerSet() ManagerSet {
+	return map[string]Manager{}
+}
+
+// InitEnforcer gets the appropriate rule Manager for the given name and uses it
+// to create an appropriate rule Enforcer.
+func (m ManagerSet) InitEnforcer(cfg Config, name string,
+	values Values) (Enforcer, error) {
+
+	mgr, ok := m[name]
+	if !ok {
+		return nil, ErrUnknownRule
+	}
+
+	return mgr.NewEnforcer(cfg, values)
+}
+
+// GetAllRules returns a map of names of all the rules supported by rule
+// ManagerSet.
+func (m ManagerSet) GetAllRules() map[string]bool {
+	rules := make(map[string]bool, len(m))
+	for name := range m {
+		rules[name] = true
+	}
+	return rules
+}
+
+// UnmarshalRuleValues identifies the appropriate rule Manager based on the
+// given rule name and uses that to parse the proto value into a Value object.
+func (m ManagerSet) UnmarshalRuleValues(name string, proto *litrpc.RuleValue) (
+	Values, error) {
+
+	mgr, ok := m[name]
+	if !ok {
+		return nil, ErrUnknownRule
+	}
+
+	return mgr.NewValueFromProto(proto)
+}
+
+// InitRuleValues can be used to construct a Values object given raw rule
+// value bytes along with the name of the appropriate rule.
+func (m ManagerSet) InitRuleValues(name string, valueBytes []byte) (Values,
+	error) {
+
+	mgr, ok := m[name]
+	if !ok {
+		return nil, ErrUnknownRule
+	}
+
+	v := mgr.EmptyValue()
+	if err := json.Unmarshal(valueBytes, v); err != nil {
+		return nil, err
+	}
+
+	return v, nil
+}
+
+// Stop stops all the managers in the set.
+func (m ManagerSet) Stop() error {
+	var returnErr error
+	for _, mgr := range m {
+		err := mgr.Stop()
+		if err != nil {
+			returnErr = err
+		}
+	}
+
+	return returnErr
+}