internal/ethapi: add db operations to api (ethereum#24739)

Adds `debug_dbGet` method to rpc api

Author: s1na

cmd/geth/dbcmd.go

@@ -18,7 +18,6 @@ package main
 
 import (
 	"bytes"
-	"errors"
 	"fmt"
 	"os"
 	"os/signal"
@@ -418,7 +417,7 @@ func dbGet(ctx *cli.Context) error {
 	db := utils.MakeChainDatabase(ctx, stack, true)
 	defer db.Close()
 
-	key, err := parseHexOrString(ctx.Args().Get(0))
+	key, err := common.ParseHexOrString(ctx.Args().Get(0))
 	if err != nil {
 		log.Info("Could not decode the key", "error", err)
 		return err
@@ -444,7 +443,7 @@ func dbDelete(ctx *cli.Context) error {
 	db := utils.MakeChainDatabase(ctx, stack, false)
 	defer db.Close()
 
-	key, err := parseHexOrString(ctx.Args().Get(0))
+	key, err := common.ParseHexOrString(ctx.Args().Get(0))
 	if err != nil {
 		log.Info("Could not decode the key", "error", err)
 		return err
@@ -477,7 +476,7 @@ func dbPut(ctx *cli.Context) error {
 		data  []byte
 		err   error
 	)
-	key, err = parseHexOrString(ctx.Args().Get(0))
+	key, err = common.ParseHexOrString(ctx.Args().Get(0))
 	if err != nil {
 		log.Info("Could not decode the key", "error", err)
 		return err
@@ -584,15 +583,6 @@ func freezerInspect(ctx *cli.Context) error {
 	return nil
 }
 
-// ParseHexOrString tries to hexdecode b, but if the prefix is missing, it instead just returns the raw bytes
-func parseHexOrString(str string) ([]byte, error) {
-	b, err := hexutil.Decode(str)
-	if errors.Is(err, hexutil.ErrMissingPrefix) {
-		return []byte(str), nil
-	}
-	return b, err
-}
-
 func importLDBdata(ctx *cli.Context) error {
 	start := 0
 	switch ctx.NArg() {

common/bytes.go

@@ -19,6 +19,9 @@ package common
 
 import (
 	"encoding/hex"
+	"errors"
+
+	"github.com/ethereum/go-ethereum/common/hexutil"
 )
 
 // FromHex returns the bytes represented by the hexadecimal string s.
@@ -92,6 +95,15 @@ func Hex2BytesFixed(str string, flen int) []byte {
 	return hh
 }
 
+// ParseHexOrString tries to hexdecode b, but if the prefix is missing, it instead just returns the raw bytes
+func ParseHexOrString(str string) ([]byte, error) {
+	b, err := hexutil.Decode(str)
+	if errors.Is(err, hexutil.ErrMissingPrefix) {
+		return []byte(str), nil
+	}
+	return b, err
+}
+
 // RightPadBytes zero-pads slice to the right up to length l.
 func RightPadBytes(slice []byte, l int) []byte {
 	if l <= len(slice) {

internal/ethapi/api.go

@@ -1972,6 +1972,15 @@ func (api *PrivateDebugAPI) SetHead(number hexutil.Uint64) {
 	api.b.SetHead(uint64(number))
 }
 
+// DbGet returns the raw value of a key stored in the database.
+func (api *PrivateDebugAPI) DbGet(key string) (hexutil.Bytes, error) {
+	blob, err := common.ParseHexOrString(key)
+	if err != nil {
+		return nil, err
+	}
+	return api.b.ChainDb().Get(blob)
+}
+
 // PublicNetAPI offers network related RPC methods
 type PublicNetAPI struct {
 	net            *p2p.Server

internal/web3ext/web3ext.go

@@ -471,6 +471,11 @@ web3._extend({
 			params: 2,
 			inputFormatter:[web3._extend.formatters.inputBlockNumberFormatter, web3._extend.formatters.inputBlockNumberFormatter],
 		}),
+		new web3._extend.Method({
+			name: 'dbGet',
+			call: 'debug_dbGet',
+			params: 1
+		}),
 	],
 	properties: []
 });