From ad77affb53096e1017bfdba28da8ac7f9547705d Mon Sep 17 00:00:00 2001
From: Christopher Goes <cwgoes@protonmail.ch>
Date: Fri, 27 Apr 2018 16:59:47 +0200
Subject: [PATCH] Add IterateAccounts & account export

---
 cmd/gaia/app/app.go          | 13 +++++++++++--
 examples/basecoin/app/app.go | 11 ++++++++++-
 examples/democoin/app/app.go | 10 +++++++++-
 types/account.go             |  1 +
 x/auth/mapper.go             | 17 +++++++++++++++++
 5 files changed, 48 insertions(+), 4 deletions(-)

diff --git a/cmd/gaia/app/app.go b/cmd/gaia/app/app.go
index 126422e2ce..532a1e095c 100644
--- a/cmd/gaia/app/app.go
+++ b/cmd/gaia/app/app.go
@@ -120,8 +120,17 @@ func (app *GaiaApp) initChainer(ctx sdk.Context, req abci.RequestInitChain) abci
 
 // custom logic for export
 func (app *GaiaApp) ExportGenesis() interface{} {
+	ctx := app.NewContext(true, abci.Header{})
+	accounts := []GenesisAccount{}
+	app.accountMapper.IterateAccounts(ctx, func(a sdk.Account) bool {
+		accounts = append(accounts, GenesisAccount{
+			Address: a.GetAddress(),
+			Coins:   a.GetCoins(),
+		})
+		return false
+	})
 	return GenesisState{
-		Accounts:  []GenesisAccount{},
-		StakeData: stake.WriteGenesis(app.NewContext(true, abci.Header{}), app.stakeKeeper),
+		Accounts:  accounts,
+		StakeData: stake.WriteGenesis(ctx, app.stakeKeeper),
 	}
 }
diff --git a/examples/basecoin/app/app.go b/examples/basecoin/app/app.go
index eb5076942f..532c25f764 100644
--- a/examples/basecoin/app/app.go
+++ b/examples/basecoin/app/app.go
@@ -128,7 +128,16 @@ func (app *BasecoinApp) initChainer(ctx sdk.Context, req abci.RequestInitChain)
 
 // Custom logic for state export
 func (app *BasecoinApp) ExportGenesis() interface{} {
+	ctx := app.NewContext(true, abci.Header{})
+	accounts := []*types.GenesisAccount{}
+	app.accountMapper.IterateAccounts(ctx, func(a sdk.Account) bool {
+		accounts = append(accounts, &types.GenesisAccount{
+			Address: a.GetAddress(),
+			Coins:   a.GetCoins(),
+		})
+		return false
+	})
 	return types.GenesisState{
-		Accounts: []*types.GenesisAccount{},
+		Accounts: accounts,
 	}
 }
diff --git a/examples/democoin/app/app.go b/examples/democoin/app/app.go
index 3b383bef8f..5f2cd32d80 100644
--- a/examples/democoin/app/app.go
+++ b/examples/democoin/app/app.go
@@ -153,8 +153,16 @@ func (app *DemocoinApp) initChainerFn(coolKeeper cool.Keeper, powKeeper pow.Keep
 // Custom logic for state export
 func (app *DemocoinApp) ExportGenesis() interface{} {
 	ctx := app.NewContext(true, abci.Header{})
+	accounts := []*types.GenesisAccount{}
+	app.accountMapper.IterateAccounts(ctx, func(a sdk.Account) bool {
+		accounts = append(accounts, &types.GenesisAccount{
+			Address: a.GetAddress(),
+			Coins:   a.GetCoins(),
+		})
+		return false
+	})
 	return types.GenesisState{
-		Accounts:    []*types.GenesisAccount{},
+		Accounts:    accounts,
 		POWGenesis:  pow.WriteGenesis(ctx, app.powKeeper),
 		CoolGenesis: cool.WriteGenesis(ctx, app.coolKeeper),
 	}
diff --git a/types/account.go b/types/account.go
index 91ad499795..33332867c6 100644
--- a/types/account.go
+++ b/types/account.go
@@ -48,6 +48,7 @@ type AccountMapper interface {
 	NewAccountWithAddress(ctx Context, addr Address) Account
 	GetAccount(ctx Context, addr Address) Account
 	SetAccount(ctx Context, acc Account)
+	IterateAccounts(ctx Context, cont func(Account) bool)
 }
 
 // AccountDecoder unmarshals account bytes
diff --git a/x/auth/mapper.go b/x/auth/mapper.go
index b815fada7a..fea98876d1 100644
--- a/x/auth/mapper.go
+++ b/x/auth/mapper.go
@@ -62,6 +62,23 @@ func (am accountMapper) SetAccount(ctx sdk.Context, acc sdk.Account) {
 	store.Set(addr, bz)
 }
 
+// Implements sdk.AccountMapper.
+func (am accountMapper) IterateAccounts(ctx sdk.Context, cont func(sdk.Account) bool) {
+	store := ctx.KVStore(am.key)
+	iter := store.Iterator(nil, nil)
+	for {
+		if !iter.Valid() {
+			return
+		}
+		val := iter.Value()
+		acc := am.decodeAccount(val)
+		if cont(acc) {
+			return
+		}
+		iter.Next()
+	}
+}
+
 //----------------------------------------
 // misc.