chore (pkg/scale) integrate scale pkg into dot/rpc (#1678)

* integrate scale into dot/sync

* integrate scale into dot/rpc

* scale into epoch

* integrate scale into pruner

* integrate scale pkg into dot/state

* WIP/Fix digest encoding errors

* remove changes in dot/state to include in separate PR

dot/rpc/modules/state.go

@@ -24,7 +24,7 @@ import (
 
 	"github.com/ChainSafe/gossamer/lib/common"
 	"github.com/ChainSafe/gossamer/lib/runtime"
-	"github.com/ChainSafe/gossamer/lib/scale"
+	"github.com/ChainSafe/gossamer/pkg/scale"
 )
 
 // StateCallRequest holds json fields
@@ -272,8 +272,9 @@ func (sm *StateModule) GetMetadata(r *http.Request, req *StateRuntimeMetadataQue
 		return err
 	}
 
-	decoded, err := scale.Decode(metadata, []byte{})
-	*res = StateMetadataResponse(common.BytesToHex(decoded.([]byte)))
+	var decoded []byte
+	err = scale.Unmarshal(metadata, &decoded)
+	*res = StateMetadataResponse(common.BytesToHex(decoded))
 	return err
 }
 

dot/rpc/modules/system.go

@@ -24,7 +24,7 @@ import (
 
 	"github.com/ChainSafe/gossamer/lib/common"
 	"github.com/ChainSafe/gossamer/lib/crypto"
-	"github.com/ChainSafe/gossamer/lib/scale"
+	"github.com/ChainSafe/gossamer/pkg/scale"
 	ctypes "github.com/centrifuge/go-substrate-rpc-client/v3/types"
 )
 
@@ -196,12 +196,13 @@ func (sm *SystemModule) AccountNextIndex(r *http.Request, req *StringRequest, re
 	if err != nil {
 		return err
 	}
-	sdMeta, err := scale.Decode(rawMeta, []byte{})
+	var sdMeta []byte
+	err = scale.Unmarshal(rawMeta, &sdMeta)
 	if err != nil {
 		return err
 	}
 	var metadata ctypes.Metadata
-	err = ctypes.DecodeFromBytes(sdMeta.([]byte), &metadata)
+	err = ctypes.DecodeFromBytes(sdMeta, &metadata)
 	if err != nil {
 		return err
 	}