Merge pull request DongCoNY#47 from onomyprotocol/add_query_price

Add query price for oracle module

proto/reserve/oracle/query.proto

@@ -21,6 +21,12 @@ service Query {
     option (google.api.http).get =
         "/reserve/oracle/band_price_states";
   }
+  // Retrieves the price of base/quote
+  rpc Price(QueryPriceRequest)
+      returns (QueryPriceResponse) {
+    option (google.api.http).get =
+      "/reserve/oracle/price";
+}
 }
 
 // QueryParamsRequest is request type for the Query/Params RPC method.
@@ -42,3 +48,17 @@ message QueryBandPriceStatesRequest {}
 message QueryBandPriceStatesResponse {
   repeated BandPriceState price_states = 1;
 }
+
+// QueryPriceRequest is the request type for the
+// Query/Price RPC method.
+message QueryPriceRequest {
+  string base_denom = 1;
+
+  string quote_denom = 2;
+}
+
+// QueryPriceResponse is the response type for the
+// Query/Price RPC method
+message QueryPriceResponse {
+  string price = 1;
+}

x/oracle/client/cli/query.go

@@ -24,6 +24,7 @@ func GetQueryCmd() *cobra.Command {
 
 	cmd.AddCommand(
 		GetBandPriceStates(),
+		GetPrice(),
 	)
 	return cmd
 }
@@ -53,4 +54,37 @@ func GetBandPriceStates() *cobra.Command {
 
 	flags.AddQueryFlagsToCmd(cmd)
 	return cmd
-}
+}
+
+// GetPrice queries the price based on rate of base/quote
+func GetPrice() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "price [base] [quote]",
+		Short: "Get price based on rate of base/quote",
+		Args:  cobra.ExactArgs(2),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			clientCtx, err := client.GetClientQueryContext(cmd)
+			if err != nil {
+				return err
+			}
+			baseDenom := args[0]
+			quoteDenom := args[1]
+
+			queryClient := types.NewQueryClient(clientCtx)
+
+			var res proto.Message
+			req := &types.QueryPriceRequest{
+				BaseDenom: baseDenom,
+				QuoteDenom: quoteDenom,
+			}
+			res, err = queryClient.Price(context.Background(), req)
+			if err != nil {
+				return err
+			}
+			return clientCtx.PrintProto(res)
+		},
+	}
+
+	flags.AddQueryFlagsToCmd(cmd)
+	return cmd
+}

x/oracle/keeper/band_oracle.go

@@ -280,6 +280,7 @@ func (k *Keeper) GetPrice(ctx context.Context, base, quote string) *math.LegacyD
 	// query ref by using GetBandPriceState
 	basePriceState := k.GetBandPriceState(ctx, base)
 	if basePriceState == nil || basePriceState.Rate.IsZero() {
+		k.Logger(ctx).Info("Can not get price state of base denom %s: price state is nil or rate is zero", base)
 		return nil
 	}
 
@@ -289,6 +290,7 @@ func (k *Keeper) GetPrice(ctx context.Context, base, quote string) *math.LegacyD
 
 	quotePriceState := k.GetBandPriceState(ctx, quote)
 	if quotePriceState == nil || quotePriceState.Rate.IsZero() {
+		k.Logger(ctx).Info("Can not get price state of quote denom %s: price state is nil or rate is zero", quote)
 		return nil
 	}
 

x/oracle/keeper/query.go

@@ -16,4 +16,14 @@ func (k Keeper) BandPriceStates(c context.Context, _ *types.QueryBandPriceStates
 	}
 
 	return res, nil
-}
+}
+
+func (k Keeper) Price(c context.Context, q *types.QueryPriceRequest) (*types.QueryPriceResponse, error) {
+	ctx := sdk.UnwrapSDKContext(c)
+
+	price := k.GetPrice(ctx, q.BaseDenom, q.QuoteDenom)
+	res := &types.QueryPriceResponse{
+		Price: price.String(),
+	}
+	return res, nil
+}