add topN endpoint to supply module (disabled by default)

proto/quicksilver/supply/v1/query.proto

@@ -1,6 +1,9 @@
 syntax = "proto3";
 package quicksilver.supply.v1;
 
+import "cosmos/base/v1beta1/coin.proto";
+import "cosmos_proto/cosmos.proto";
+import "gogoproto/gogo.proto";
 import "google/api/annotations.proto";
 
 option go_package = "github.com/quicksilver-zone/quicksilver/x/supply/types";
@@ -11,10 +14,30 @@ service Query {
   rpc Supply(QuerySupplyRequest) returns (QuerySupplyResponse) {
     option (google.api.http).get = "/quicksilver/supply/v1/supply";
   }
+
+  rpc TopN(QueryTopNRequest) returns (QueryTopNResponse) {
+    option (google.api.http).get = "/quicksilver/supply/v1/topn/{n}";
+  }
 }
 
 message QuerySupplyRequest {}
 message QuerySupplyResponse {
   uint64 supply = 1;
   uint64 circulating_supply = 2;
 }
+
+message Account {
+  string address = 1;
+  string balance = 2 [
+    (cosmos_proto.scalar) = "cosmos.Int",
+    (gogoproto.customtype) = "cosmossdk.io/math.Int",
+    (gogoproto.nullable) = false
+  ];
+}
+
+message QueryTopNRequest {
+  uint64 n = 1;
+}
+message QueryTopNResponse {
+  repeated Account accounts = 1;
+}

x/supply/keeper/grpc_query.go

@@ -44,3 +44,15 @@
 	}
 	return nil, fmt.Errorf("endpoint disabled")
 }
+
+func (q Querier) TopN(c context.Context, req *types.QueryTopNRequest) (*types.QueryTopNResponse, error) {
+	ctx := sdk.UnwrapSDKContext(c)
+
+	if q.endpointEnabled {
+
+		accounts := q.Keeper.TopN(ctx, q.stakingKeeper.BondDenom(ctx), int(req.N))
+
+		return &types.QueryTopNResponse{Accounts: accounts}, nil
+	}
+	return nil, fmt.Errorf("endpoint disabled")
+}

x/supply/keeper/keeper.go

@@ -1,6 +1,8 @@
 package keeper
 
 import (
+	"sort"
+
 	"github.com/tendermint/tendermint/libs/log"
 
 	"cosmossdk.io/math"
@@ -79,3 +81,42 @@ func (k Keeper) CalculateCirculatingSupply(ctx sdk.Context, baseDenom string, ex
 
 	return k.bankKeeper.GetSupply(ctx, baseDenom).Amount.Sub(nonCirculating)
 }
+
+func (k Keeper) TopN(ctx sdk.Context, baseDenom string, n int) []*types.Account {
+	accountMap := map[string]math.Int{}
+
+	modMap := map[string]bool{}
+
+	for _, mod := range k.moduleAccounts {
+		modMap[k.accountKeeper.GetModuleAddress(mod).String()] = true
+	}
+
+	k.accountKeeper.IterateAccounts(ctx, func(account authtypes.AccountI) (stop bool) {
+		if modMap[account.GetAddress().String()] {
+			return false
+		}
+		balance := k.bankKeeper.GetBalance(ctx, account.GetAddress(), baseDenom).Amount
+		accountMap[account.GetAddress().String()] = balance
+		return false
+	})
+
+	k.stakingKeeper.IterateAllDelegations(ctx, func(delegation stakingtypes.Delegation) (stop bool) {
+		if modMap[delegation.GetDelegatorAddr().String()] {
+			return false
+		}
+		balance := delegation.GetShares().TruncateInt()
+		accountMap[delegation.GetDelegatorAddr().String()] = accountMap[delegation.GetDelegatorAddr().String()].Add(balance)
+		return false
+	})
+
+	accountSlice := []*types.Account{}
+	for addr, balance := range accountMap {
+		accountSlice = append(accountSlice, &types.Account{Address: addr, Balance: balance})
+	}
+
+	sort.Slice(accountSlice, func(i, j int) bool {
+		return accountSlice[i].Balance.GT(accountSlice[j].Balance)
+	})
+
+	return accountSlice[:n]
+}

x/supply/types/expected_keepers.go

@@ -3,6 +3,7 @@ package types // noalias
 import (
 	sdk "github.com/cosmos/cosmos-sdk/types"
 	authtypes "github.com/cosmos/cosmos-sdk/x/auth/types"
+	stakingtypes "github.com/cosmos/cosmos-sdk/x/staking/types"
 )
 
 // AccountKeeper defines the contract required for account APIs.
@@ -21,4 +22,5 @@ type BankKeeper interface {
 
 type StakingKeeper interface {
 	BondDenom(ctx sdk.Context) string
+	IterateAllDelegations(ctx sdk.Context, cb func(delegation stakingtypes.Delegation) (stop bool))
 }