Abstracts away from pubkey addr -> app/chain-specific "actors"

context.go

@@ -2,21 +2,27 @@ package basecoin
 
 import "github.com/tendermint/go-wire/data"
 
-type Permission struct {
-	App     string     // Which app authorized this?
-	Address data.Bytes // App-specific identifier
+// Actor abstracts any address that can authorize actions, hold funds,
+// or initiate any sort of transaction.
+//
+// It doesn't just have to be a pubkey on this chain, it could stem from
+// another app (like multi-sig account), or even another chain (via IBC)
+type Actor struct {
+	ChainID string     // this is empty unless it comes from a different chain
+	App     string     // the app that the actor belongs to
+	Address data.Bytes // arbitrary app-specific unique id
 }
 
-func NewPermission(app string, addr []byte) Permission {
-	return Permission{App: app, Address: addr}
+func NewActor(app string, addr []byte) Actor {
+	return Actor{App: app, Address: addr}
 }
 
 // Context is an interface, so we can implement "secure" variants that
 // rely on private fields to control the actions
 type Context interface {
 	// context.Context
-	WithPermissions(perms ...Permission) Context
-	HasPermission(perm Permission) bool
+	WithPermissions(perms ...Actor) Context
+	HasPermission(perm Actor) bool
 	IsParent(ctx Context) bool
 	Reset() Context
 }

handlers/base.go

@@ -13,11 +13,11 @@ const (
 
 type AccountChecker interface {
 	// Get amount checks the current amount
-	GetAmount(store types.KVStore, addr []byte) (types.Coins, error)
+	GetAmount(store types.KVStore, addr basecoin.Actor) (types.Coins, error)
 
 	// ChangeAmount modifies the balance by the given amount and returns the new balance
 	// always returns an error if leading to negative balance
-	ChangeAmount(store types.KVStore, addr []byte, coins types.Coins) (types.Coins, error)
+	ChangeAmount(store types.KVStore, addr basecoin.Actor, coins types.Coins) (types.Coins, error)
 }
 
 type SimpleFeeHandler struct {
@@ -44,7 +44,7 @@ func (h SimpleFeeHandler) CheckTx(ctx basecoin.Context, store types.KVStore, tx
 		return res, errors.InsufficientFees()
 	}
 
-	if !ctx.HasPermission(SigPerm(feeTx.Payer)) {
+	if !ctx.HasPermission(feeTx.Payer) {
 		return res, errors.Unauthorized()
 	}
 
@@ -67,7 +67,7 @@ func (h SimpleFeeHandler) DeliverTx(ctx basecoin.Context, store types.KVStore, t
 		return res, errors.InsufficientFees()
 	}
 
-	if !ctx.HasPermission(SigPerm(feeTx.Payer)) {
+	if !ctx.HasPermission(feeTx.Payer) {
 		return res, errors.Unauthorized()
 	}
 

handlers/sigs.go

@@ -23,8 +23,8 @@ func (_ SignedHandler) Name() string {
 
 var _ basecoin.Middleware = SignedHandler{}
 
-func SigPerm(addr []byte) basecoin.Permission {
-	return basecoin.Permission{App: NameSigs, Address: addr}
+func SigPerm(addr []byte) basecoin.Actor {
+	return basecoin.NewActor(NameSigs, addr)
 }
 
 // Signed allows us to use txs.OneSig and txs.MultiSig (and others??)
@@ -52,7 +52,7 @@ func (h SignedHandler) DeliverTx(ctx basecoin.Context, store types.KVStore, tx b
 }
 
 func addSigners(ctx basecoin.Context, sigs []crypto.PubKey) basecoin.Context {
-	perms := make([]basecoin.Permission, len(sigs))
+	perms := make([]basecoin.Actor, len(sigs))
 	for i, s := range sigs {
 		perms[i] = SigPerm(s.Address())
 	}

stack/context.go

@@ -15,7 +15,7 @@ type nonce int64
 type secureContext struct {
 	id    nonce
 	app   string
-	perms []basecoin.Permission
+	perms []basecoin.Actor
 }
 
 func NewContext() basecoin.Context {
@@ -27,7 +27,7 @@ func NewContext() basecoin.Context {
 var _ basecoin.Context = secureContext{}
 
 // WithPermissions will panic if they try to set permission without the proper app
-func (c secureContext) WithPermissions(perms ...basecoin.Permission) basecoin.Context {
+func (c secureContext) WithPermissions(perms ...basecoin.Actor) basecoin.Context {
 	// the guard makes sure you only set permissions for the app you are inside
 	for _, p := range perms {
 		if p.App != c.app {
@@ -42,7 +42,7 @@ func (c secureContext) WithPermissions(perms ...basecoin.Permission) basecoin.Co
 	}
 }
 
-func (c secureContext) HasPermission(perm basecoin.Permission) bool {
+func (c secureContext) HasPermission(perm basecoin.Actor) bool {
 	for _, p := range c.perms {
 		if perm.App == p.App && bytes.Equal(perm.Address, p.Address) {
 			return true

txs/base.go

@@ -67,14 +67,14 @@ func NewRaw(d []byte) Raw {
 
 // Fee attaches a fee payment to the embedded tx
 type Fee struct {
-	Tx    basecoin.Tx `json:"tx"`
-	Fee   types.Coin  `json:"fee"`
-	Payer data.Bytes  `json:"payer"` // the address who pays the fee
+	Tx    basecoin.Tx    `json:"tx"`
+	Fee   types.Coin     `json:"fee"`
+	Payer basecoin.Actor `json:"payer"` // the address who pays the fee
 	// Gas types.Coin `json:"gas"`  // ?????
 }
 
-func NewFee(tx basecoin.Tx, fee types.Coin, addr []byte) *Fee {
-	return &Fee{Tx: tx, Fee: fee, Payer: addr}
+func NewFee(tx basecoin.Tx, fee types.Coin, payer basecoin.Actor) *Fee {
+	return &Fee{Tx: tx, Fee: fee, Payer: payer}
 }
 
 func (f *Fee) ValidateBasic() error {

txs/send.go

@@ -4,7 +4,6 @@ import (
 	"fmt"
 
 	"github.com/tendermint/basecoin"
-	"github.com/tendermint/go-wire/data"
 
 	"github.com/tendermint/basecoin/errors"
 	"github.com/tendermint/basecoin/types"
@@ -13,13 +12,14 @@ import (
 //-----------------------------------------------------------------------------
 
 type TxInput struct {
-	Address  data.Bytes  `json:"address"`
-	Coins    types.Coins `json:"coins"`
-	Sequence int         `json:"sequence"` // Nonce: Must be 1 greater than the last committed TxInput
+	Address  basecoin.Actor `json:"address"`
+	Coins    types.Coins    `json:"coins"`
+	Sequence int            `json:"sequence"` // Nonce: Must be 1 greater than the last committed TxInput
 }
 
 func (txIn TxInput) ValidateBasic() error {
-	if len(txIn.Address) != 20 {
+	// TODO: knowledge of app-specific codings?
+	if txIn.Address.App == "" {
 		return errors.InvalidAddress()
 	}
 	if !txIn.Coins.IsValid() {
@@ -38,7 +38,7 @@ func (txIn TxInput) String() string {
 	return fmt.Sprintf("TxInput{%v,%v,%v}", txIn.Address, txIn.Coins, txIn.Sequence)
 }
 
-func NewTxInput(addr []byte, coins types.Coins, sequence int) TxInput {
+func NewTxInput(addr basecoin.Actor, coins types.Coins, sequence int) TxInput {
 	input := TxInput{
 		Address:  addr,
 		Coins:    coins,
@@ -50,12 +50,13 @@ func NewTxInput(addr []byte, coins types.Coins, sequence int) TxInput {
 //-----------------------------------------------------------------------------
 
 type TxOutput struct {
-	Address data.Bytes  `json:"address"`
-	Coins   types.Coins `json:"coins"`
+	Address basecoin.Actor `json:"address"`
+	Coins   types.Coins    `json:"coins"`
 }
 
 func (txOut TxOutput) ValidateBasic() error {
-	if len(txOut.Address) != 20 {
+	// TODO: knowledge of app-specific codings?
+	if txOut.Address.App == "" {
 		return errors.InvalidAddress()
 	}
 	if !txOut.Coins.IsValid() {
@@ -71,7 +72,7 @@ func (txOut TxOutput) String() string {
 	return fmt.Sprintf("TxOutput{%X,%v}", txOut.Address, txOut.Coins)
 }
 
-func NewTxOutput(addr []byte, coins types.Coins) TxOutput {
+func NewTxOutput(addr basecoin.Actor, coins types.Coins) TxOutput {
 	output := TxOutput{
 		Address: addr,
 		Coins:   coins,