feat(rpc): Allowing for ValAddr on /transfer and /balance/$ADDRESS (#1102)

* feat(rpc): Allowing for ValAddr on /transfer and /balance/ADDRESS

* refactor(rpc): error variables in rpc/state.go

* chore(lint): fixing ineffassign and making const from addrKey

Author: distractedm1nd

Diff for: service/rpc/state.go

@@ -26,7 +26,13 @@ const (
 	queryRedelegationsEndpoint = "/query_redelegations"
 )
 
-var addrKey = "address"
+const addrKey = "address"
+
+var (
+	ErrInvalidAddressFormat = errors.New("address must be a valid account or validator address")
+	ErrMissingAddress       = errors.New("address not specified")
+	ErrInvalidAmount        = errors.New("amount must be greater than zero")
+)
 
 // submitTxRequest represents a request to submit a raw transaction
 type submitTxRequest struct {
@@ -78,6 +84,7 @@ type cancelUnbondRequest struct {
 	GasLimit uint64 `json:"gas_limit"`
 }
 
+// queryRedelegationsRequest represents a request to query redelegations
 type queryRedelegationsRequest struct {
 	From string `json:"from"`
 	To   string `json:"to"`
@@ -93,10 +100,16 @@ func (h *Handler) handleBalanceRequest(w http.ResponseWriter, r *http.Request) {
 	addrStr, exists := vars[addrKey]
 	if exists {
 		// convert address to Address type
-		addr, addrerr := types.AccAddressFromBech32(addrStr)
-		if addrerr != nil {
-			writeError(w, http.StatusBadRequest, balanceEndpoint, addrerr)
-			return
+		var addr state.AccAddress
+		addr, err = types.AccAddressFromBech32(addrStr)
+		if err != nil {
+			// first check if it is a validator address and can be converted
+			valAddr, err := types.ValAddressFromBech32(addrStr)
+			if err != nil {
+				writeError(w, http.StatusBadRequest, balanceEndpoint, ErrInvalidAddressFormat)
+				return
+			}
+			addr = valAddr.Bytes()
 		}
 		bal, err = h.state.BalanceForAddress(r.Context(), addr)
 	} else {
@@ -190,13 +203,18 @@ func (h *Handler) handleTransfer(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	if req.Amount <= 0 {
-		writeError(w, http.StatusBadRequest, transferEndpoint, errors.New("amount must be greater than 0"))
+		writeError(w, http.StatusBadRequest, transferEndpoint, ErrInvalidAmount)
 		return
 	}
 	addr, err := types.AccAddressFromBech32(req.To)
 	if err != nil {
-		writeError(w, http.StatusBadRequest, transferEndpoint, err)
-		return
+		// first check if it is a validator address and can be converted
+		valAddr, err := types.ValAddressFromBech32(req.To)
+		if err != nil {
+			writeError(w, http.StatusBadRequest, transferEndpoint, ErrInvalidAddressFormat)
+			return
+		}
+		addr = valAddr.Bytes()
 	}
 	amount := types.NewInt(req.Amount)
 
@@ -224,7 +242,7 @@ func (h *Handler) handleDelegation(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	if req.Amount <= 0 {
-		writeError(w, http.StatusBadRequest, delegationEndpoint, errors.New("amount must be greater than 0"))
+		writeError(w, http.StatusBadRequest, delegationEndpoint, ErrInvalidAmount)
 		return
 	}
 	addr, err := types.ValAddressFromBech32(req.To)
@@ -258,7 +276,7 @@ func (h *Handler) handleUndelegation(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	if req.Amount <= 0 {
-		writeError(w, http.StatusBadRequest, undelegationEndpoint, errors.New("amount must be greater than 0"))
+		writeError(w, http.StatusBadRequest, undelegationEndpoint, ErrInvalidAmount)
 		return
 	}
 	addr, err := types.ValAddressFromBech32(req.From)
@@ -292,7 +310,7 @@ func (h *Handler) handleCancelUnbonding(w http.ResponseWriter, r *http.Request)
 		return
 	}
 	if req.Amount <= 0 {
-		writeError(w, http.StatusBadRequest, cancelUnbondingEndpoint, errors.New("amount must be greater than 0"))
+		writeError(w, http.StatusBadRequest, cancelUnbondingEndpoint, ErrInvalidAmount)
 		return
 	}
 	addr, err := types.ValAddressFromBech32(req.From)
@@ -326,7 +344,7 @@ func (h *Handler) handleRedelegation(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	if req.Amount <= 0 {
-		writeError(w, http.StatusBadRequest, beginRedelegationEndpoint, errors.New("amount must be greater than 0"))
+		writeError(w, http.StatusBadRequest, beginRedelegationEndpoint, ErrInvalidAmount)
 		return
 	}
 	srcAddr, err := types.ValAddressFromBech32(req.From)
@@ -362,7 +380,7 @@ func (h *Handler) handleQueryDelegation(w http.ResponseWriter, r *http.Request)
 	vars := mux.Vars(r)
 	addrStr, exists := vars[addrKey]
 	if !exists {
-		writeError(w, http.StatusBadRequest, queryDelegationEndpoint, errors.New("address not specified"))
+		writeError(w, http.StatusBadRequest, queryDelegationEndpoint, ErrMissingAddress)
 		return
 	}
 
@@ -393,7 +411,7 @@ func (h *Handler) handleQueryUnbonding(w http.ResponseWriter, r *http.Request) {
 	vars := mux.Vars(r)
 	addrStr, exists := vars[addrKey]
 	if !exists {
-		writeError(w, http.StatusBadRequest, queryUnbondingEndpoint, errors.New("address not specified"))
+		writeError(w, http.StatusBadRequest, queryUnbondingEndpoint, ErrMissingAddress)
 		return
 	}
 

Diff for: service/state/core_access.go

@@ -136,7 +136,7 @@ func (ca *CoreAccessor) Balance(ctx context.Context) (*Balance, error) {
 	return ca.BalanceForAddress(ctx, addr)
 }
 
-func (ca *CoreAccessor) BalanceForAddress(ctx context.Context, addr AccAddress) (*Balance, error) {
+func (ca *CoreAccessor) BalanceForAddress(ctx context.Context, addr Address) (*Balance, error) {
 	head, err := ca.getter.Head(ctx)
 	if err != nil {
 		return nil, err

Diff for: service/state/interface.go

@@ -27,7 +27,7 @@ type Accessor interface {
 	// NOTE: the balance returned is the balance reported by the block right before
 	// the node's current head (head-1). This is due to the fact that for block N, the block's
 	// `AppHash` is the result of applying the previous block's transaction list.
-	BalanceForAddress(ctx context.Context, addr AccAddress) (*Balance, error)
+	BalanceForAddress(ctx context.Context, addr Address) (*Balance, error)
 
 	// Transfer sends the given amount of coins from default wallet of the node to the given account address.
 	Transfer(ctx context.Context, to AccAddress, amount math.Int, gasLimit uint64) (*TxResponse, error)

Diff for: service/state/service.go

@@ -37,7 +37,7 @@ func (s *Service) Balance(ctx context.Context) (*Balance, error) {
 	return s.accessor.Balance(ctx)
 }
 
-func (s *Service) BalanceForAddress(ctx context.Context, addr AccAddress) (*Balance, error) {
+func (s *Service) BalanceForAddress(ctx context.Context, addr Address) (*Balance, error) {
 	return s.accessor.BalanceForAddress(ctx, addr)
 }
 

Diff for: service/state/state.go

@@ -15,6 +15,9 @@ type Tx = coretypes.Tx
 // TxResponse is an alias to the TxResponse type from Cosmos-SDK.
 type TxResponse = sdk.TxResponse
 
+// Address is an alias to the Address type from Cosmos-SDK.
+type Address = sdk.Address
+
 // ValAddress is an alias to the ValAddress type from Cosmos-SDK.
 type ValAddress = sdk.ValAddress