From 9c6ef3e23c75a6e987173bacf6a9558abd4bc8b2 Mon Sep 17 00:00:00 2001
From: Sunny Aggarwal <sunnya97@protonmail.ch>
Date: Tue, 23 Oct 2018 00:42:06 -0700
Subject: [PATCH] added validatorDelegations querier endpoint

---
 x/stake/keeper/delegation.go      | 17 ++++++++++++++++-
 x/stake/querier/queryable.go      | 21 +++++++++++++++++++++
 x/stake/querier/queryable_test.go | 26 ++++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 1 deletion(-)

diff --git a/x/stake/keeper/delegation.go b/x/stake/keeper/delegation.go
index 97acc2404..9a5a7549d 100644
--- a/x/stake/keeper/delegation.go
+++ b/x/stake/keeper/delegation.go
@@ -24,7 +24,7 @@ func (k Keeper) GetDelegation(ctx sdk.Context,
 	return delegation, true
 }
 
-// return all delegations used during genesis dump
+// return all delegations to a specific validator. Useful for querier.
 func (k Keeper) GetAllDelegations(ctx sdk.Context) (delegations []types.Delegation) {
 	store := ctx.KVStore(k.storeKey)
 	iterator := sdk.KVStorePrefixIterator(store, DelegationKey)
@@ -37,6 +37,21 @@ func (k Keeper) GetAllDelegations(ctx sdk.Context) (delegations []types.Delegati
 	return delegations
 }
 
+// return all delegations used during genesis dump
+func (k Keeper) GetAllDelegationsToValidator(ctx sdk.Context, valAddr sdk.ValAddress) (delegations []types.Delegation) {
+	store := ctx.KVStore(k.storeKey)
+	iterator := sdk.KVStorePrefixIterator(store, DelegationKey)
+	defer iterator.Close()
+
+	for ; iterator.Valid(); iterator.Next() {
+		delegation := types.MustUnmarshalDelegation(k.cdc, iterator.Key(), iterator.Value())
+		if delegation.GetValidator().Equals(valAddr) {
+			delegations = append(delegations, delegation)
+		}
+	}
+	return delegations
+}
+
 // return a given amount of all the delegations from a delegator
 func (k Keeper) GetDelegatorDelegations(ctx sdk.Context, delegator sdk.AccAddress,
 	maxRetrieve uint16) (delegations []types.Delegation) {
diff --git a/x/stake/querier/queryable.go b/x/stake/querier/queryable.go
index 4f9eb2bc7..a963d7ca8 100644
--- a/x/stake/querier/queryable.go
+++ b/x/stake/querier/queryable.go
@@ -15,6 +15,7 @@ const (
 	QueryDelegatorDelegations          = "delegatorDelegations"
 	QueryDelegatorUnbondingDelegations = "delegatorUnbondingDelegations"
 	QueryDelegatorRedelegations        = "delegatorRedelegations"
+	QueryValidatorDelegations          = "validatorDelegations"
 	QueryValidatorUnbondingDelegations = "validatorUnbondingDelegations"
 	QueryValidatorRedelegations        = "validatorRedelegations"
 	QueryDelegator                     = "delegator"
@@ -35,6 +36,8 @@ func NewQuerier(k keep.Keeper, cdc *codec.Codec) sdk.Querier {
 			return queryValidators(ctx, cdc, k)
 		case QueryValidator:
 			return queryValidator(ctx, cdc, req, k)
+		case QueryValidatorDelegations:
+			return queryValidatorDelegations(ctx, cdc, req, k)
 		case QueryValidatorUnbondingDelegations:
 			return queryValidatorUnbondingDelegations(ctx, cdc, req, k)
 		case QueryValidatorRedelegations:
@@ -74,6 +77,7 @@ type QueryDelegatorParams struct {
 
 // defines the params for the following queries:
 // - 'custom/stake/validator'
+// - 'custom/stake/validatorDelegations'
 // - 'custom/stake/validatorUnbondingDelegations'
 // - 'custom/stake/validatorRedelegations'
 type QueryValidatorParams struct {
@@ -128,6 +132,23 @@ func queryValidator(ctx sdk.Context, cdc *codec.Codec, req abci.RequestQuery, k
 	return res, nil
 }
 
+func queryValidatorDelegations(ctx sdk.Context, cdc *codec.Codec, req abci.RequestQuery, k keep.Keeper) (res []byte, err sdk.Error) {
+	var params QueryValidatorParams
+
+	errRes := cdc.UnmarshalJSON(req.Data, &params)
+	if errRes != nil {
+		return []byte{}, sdk.ErrUnknownAddress("")
+	}
+
+	delegations := k.GetAllDelegationsToValidator(ctx, params.ValidatorAddr)
+
+	res, errRes = codec.MarshalJSONIndent(cdc, delegations)
+	if errRes != nil {
+		return nil, sdk.ErrInternal(sdk.AppendMsgToErr("could not marshal result to JSON", errRes.Error()))
+	}
+	return res, nil
+}
+
 func queryValidatorUnbondingDelegations(ctx sdk.Context, cdc *codec.Codec, req abci.RequestQuery, k keep.Keeper) (res []byte, err sdk.Error) {
 	var params QueryValidatorParams
 
diff --git a/x/stake/querier/queryable_test.go b/x/stake/querier/queryable_test.go
index 2fac1a27a..0f47c60c6 100644
--- a/x/stake/querier/queryable_test.go
+++ b/x/stake/querier/queryable_test.go
@@ -90,6 +90,9 @@ func TestNewQuerier(t *testing.T) {
 	_, err = querier(ctx, []string{"validator"}, query)
 	require.Nil(t, err)
 
+	_, err = querier(ctx, []string{"validatorDelegations"}, query)
+	require.Nil(t, err)
+
 	_, err = querier(ctx, []string{"validatorUnbondingDelegations"}, query)
 	require.Nil(t, err)
 
@@ -301,9 +304,32 @@ func TestQueryDelegation(t *testing.T) {
 	_, err = queryDelegation(ctx, cdc, query, keeper)
 	require.NotNil(t, err)
 
+	// Query validator delegations
+
+	bz, errRes = cdc.MarshalJSON(newTestValidatorQuery(addrVal1))
+	require.Nil(t, errRes)
+
+	query = abci.RequestQuery{
+		Path: "custom/stake/validatorDelegations",
+		Data: bz,
+	}
+
+	res, err = queryValidatorDelegations(ctx, cdc, query, keeper)
+	require.Nil(t, err)
+
+	var delegationsRes []types.Delegation
+	errRes = cdc.UnmarshalJSON(res, &delegationsRes)
+	require.Nil(t, errRes)
+
+	require.Equal(t, delegationsRes[0], delegation)
+
 	// Query unbonging delegation
 	keeper.BeginUnbonding(ctx, addrAcc2, val1.OperatorAddr, sdk.NewDec(10))
 
+	queryBondParams = newTestBondQuery(addrAcc2, addrVal1)
+	bz, errRes = cdc.MarshalJSON(queryBondParams)
+	require.Nil(t, errRes)
+
 	query = abci.RequestQuery{
 		Path: "/custom/stake/unbondingDelegation",
 		Data: bz,