refactor: add legacy params for easier migration

x/authority/types/params_legacy.go

@@ -0,0 +1,46 @@
+package types
+
+import (
+	"fmt"
+
+	"cosmossdk.io/errors"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	paramstypes "github.com/cosmos/cosmos-sdk/x/params/types"
+)
+
+var _ paramstypes.ParamSet = &Params{}
+
+// Params is the legacy ParamAuthority interface.
+// https://github.com/strangelove-ventures/paramauthority/blob/v1.1.0/x/params/types/proposal/genesis.pb.go#L71-L74
+type Params struct {
+	Authority string `protobuf:"bytes,1,opt,name=authority,proto3" json:"authority,omitempty" yaml:"authority"`
+}
+
+// Deprecated: ParamKeyTable returns the legacy ParamAuthority key table.
+// https://github.com/strangelove-ventures/paramauthority/blob/v1.1.0/x/params/types/proposal/params.go#L11-L14
+func ParamKeyTable() paramstypes.KeyTable {
+	return paramstypes.NewKeyTable().RegisterParamSet(&Params{})
+}
+
+// ParamSetPairs implements the ParamSet interface.
+// https://github.com/strangelove-ventures/paramauthority/blob/v1.1.0/x/params/types/proposal/params.go#L33-L38
+func (p *Params) ParamSetPairs() paramstypes.ParamSetPairs {
+	return paramstypes.ParamSetPairs{
+		paramstypes.NewParamSetPair(AuthorityKey, p.Authority, validateAuthority),
+	}
+}
+
+// https://github.com/strangelove-ventures/paramauthority/blob/v1.1.0/x/params/types/proposal/params.go#L40-L51
+func validateAuthority(i interface{}) error {
+	a, ok := i.(string)
+	if !ok {
+		return fmt.Errorf("invalid parameter type: %T", i)
+	}
+
+	if _, err := sdk.AccAddressFromBech32(a); err != nil {
+		return errors.Wrap(err, "authority")
+	}
+
+	return nil
+}