supply querier (cosmos#4592)

Add querier to the supply module.

Closes: cosmos#4082

.pending/improvements/sdk/4595-supply-queriers

@@ -0,0 +1 @@
+#4082 supply module queriers for CLI and REST endpoints

client/lcd/swagger-ui/swagger.yaml

@@ -21,6 +21,9 @@ tags:
     description: Slashing module APIs
   - name: Distribution
     description: Fee distribution module APIs
+  - name: Supply
+    description: Supply module APIs
+  - name: version
   - name: Mint
     description: Minting module APIs
   - name: Misc
@@ -1827,6 +1830,43 @@ paths:
             type: string
         500:
           description: Internal Server Error
+  /supply/total:
+    get:
+      summary: Total supply of coins in the chain
+      tags:
+        - Supply
+      produces:
+        - application/json
+      responses:
+        200:
+          description: OK
+          schema:
+            $ref: "#/definitions/Supply"
+        500:
+          description: Internal Server Error
+  /supply/total/{denomination}:
+    parameters:
+      - in: path
+        name: denomination
+        description: Coin denomination
+        required: true
+        type: string
+        x-example: uatom
+    get:
+      summary: Total supply of a single coin denomination
+      tags:
+        - Supply
+      produces:
+        - application/json
+      responses:
+        200:
+          description: OK
+          schema:
+             type: integer
+        400:
+          description: Invalid coin denomination
+        500:
+          description: Internal Server Error
 definitions:
   CheckTxResult:
     type: object
@@ -2435,3 +2475,10 @@ definitions:
         example: ""
       value:
         type: object
+  Supply:
+    type: object
+    properties:
+      total:
+        type: array
+        items:
+          $ref: "#/definitions/Coin"

x/supply/client/cli/query.go

@@ -0,0 +1,104 @@
+package cli
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/cosmos/cosmos-sdk/client"
+	"github.com/cosmos/cosmos-sdk/client/context"
+	"github.com/cosmos/cosmos-sdk/codec"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/cosmos-sdk/version"
+	"github.com/cosmos/cosmos-sdk/x/supply/types"
+	"github.com/spf13/cobra"
+)
+
+// GetQueryCmd returns the cli query commands for this module
+func GetQueryCmd(cdc *codec.Codec) *cobra.Command {
+	// Group supply queries under a subcommand
+	supplyQueryCmd := &cobra.Command{
+		Use:                        types.ModuleName,
+		Short:                      "Querying commands for the supply module",
+		DisableFlagParsing:         true,
+		SuggestionsMinimumDistance: 2,
+		RunE:                       client.ValidateCmd,
+	}
+
+	supplyQueryCmd.AddCommand(client.GetCommands(
+		GetCmdQueryTotalSupply(cdc),
+	)...)
+
+	return supplyQueryCmd
+}
+
+// GetCmdQueryTotalSupply implements the query total supply command.
+func GetCmdQueryTotalSupply(cdc *codec.Codec) *cobra.Command {
+	return &cobra.Command{
+		Use:   "total [denom]",
+		Args:  cobra.MaximumNArgs(1),
+		Short: "Query the total supply of coins of the chain",
+		Long: strings.TrimSpace(
+			fmt.Sprintf(`Query total supply of coins that are held by accounts in the
+			chain.
+
+Example:
+$ %s query %s total
+
+To query for the total supply of a specific coin denomination use:
+$ %s query %s total stake
+`,
+				version.ClientName, types.ModuleName, version.ClientName, types.ModuleName,
+			),
+		),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			cliCtx := context.NewCLIContext().WithCodec(cdc)
+
+			if len(args) == 0 {
+				return queryTotalSupply(cliCtx, cdc)
+			}
+			return querySupplyOf(cliCtx, cdc, args[0])
+		},
+	}
+}
+
+func queryTotalSupply(cliCtx context.CLIContext, cdc *codec.Codec) error {
+	params := types.NewQueryTotalSupplyParams(1, 0) // no pagination
+	bz, err := cdc.MarshalJSON(params)
+	if err != nil {
+		return err
+	}
+
+	res, _, err := cliCtx.QueryWithData(fmt.Sprintf("custom/%s/%s", types.QuerierRoute, types.QueryTotalSupply), bz)
+	if err != nil {
+		return err
+	}
+
+	var totalSupply sdk.Coins
+	err = cdc.UnmarshalJSON(res, &totalSupply)
+	if err != nil {
+		return err
+	}
+
+	return cliCtx.PrintOutput(totalSupply)
+}
+
+func querySupplyOf(cliCtx context.CLIContext, cdc *codec.Codec, denom string) error {
+	params := types.NewQuerySupplyOfParams(denom)
+	bz, err := cdc.MarshalJSON(params)
+	if err != nil {
+		return err
+	}
+
+	res, _, err := cliCtx.QueryWithData(fmt.Sprintf("custom/%s/%s", types.QuerierRoute, types.QuerySupplyOf), bz)
+	if err != nil {
+		return err
+	}
+
+	var supply sdk.Int
+	err = cdc.UnmarshalJSON(res, &supply)
+	if err != nil {
+		return err
+	}
+
+	return cliCtx.PrintOutput(supply)
+}

x/supply/client/rest/query.go

@@ -0,0 +1,90 @@
+package rest
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/gorilla/mux"
+
+	"github.com/cosmos/cosmos-sdk/client/context"
+	"github.com/cosmos/cosmos-sdk/types/rest"
+	"github.com/cosmos/cosmos-sdk/x/supply/types"
+)
+
+// RegisterRoutes registers staking-related REST handlers to a router
+func RegisterRoutes(cliCtx context.CLIContext, r *mux.Router) {
+	registerQueryRoutes(cliCtx, r)
+}
+
+func registerQueryRoutes(cliCtx context.CLIContext, r *mux.Router) {
+	// Query the total supply of coins
+	r.HandleFunc(
+		"/supply/total/",
+		totalSupplyHandlerFn(cliCtx),
+	).Methods("GET")
+
+	// Query the supply of a single denom
+	r.HandleFunc(
+		"/supply/total/{denom}",
+		supplyOfHandlerFn(cliCtx),
+	).Methods("GET")
+}
+
+// HTTP request handler to query the total supply of coins
+func totalSupplyHandlerFn(cliCtx context.CLIContext) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		_, page, limit, err := rest.ParseHTTPArgsWithLimit(r, 0)
+		if err != nil {
+			rest.WriteErrorResponse(w, http.StatusBadRequest, err.Error())
+			return
+		}
+
+		cliCtx, ok := rest.ParseQueryHeightOrReturnBadRequest(w, cliCtx, r)
+		if !ok {
+			return
+		}
+
+		params := types.NewQueryTotalSupplyParams(page, limit)
+		bz, err := cliCtx.Codec.MarshalJSON(params)
+		if err != nil {
+			rest.WriteErrorResponse(w, http.StatusBadRequest, err.Error())
+			return
+		}
+
+		res, height, err := cliCtx.QueryWithData(fmt.Sprintf("custom/%s/%s", types.QuerierRoute, types.QueryTotalSupply), bz)
+		if err != nil {
+			rest.WriteErrorResponse(w, http.StatusInternalServerError, err.Error())
+			return
+		}
+
+		cliCtx = cliCtx.WithHeight(height)
+		rest.PostProcessResponse(w, cliCtx, res)
+	}
+}
+
+// HTTP request handler to query the supply of a single denom
+func supplyOfHandlerFn(cliCtx context.CLIContext) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		denom := mux.Vars(r)["denom"]
+		cliCtx, ok := rest.ParseQueryHeightOrReturnBadRequest(w, cliCtx, r)
+		if !ok {
+			return
+		}
+
+		params := types.NewQuerySupplyOfParams(denom)
+		bz, err := cliCtx.Codec.MarshalJSON(params)
+		if err != nil {
+			rest.WriteErrorResponse(w, http.StatusBadRequest, err.Error())
+			return
+		}
+
+		res, height, err := cliCtx.QueryWithData(fmt.Sprintf("custom/%s/%s", types.QuerierRoute, types.QuerySupplyOf), bz)
+		if err != nil {
+			rest.WriteErrorResponse(w, http.StatusInternalServerError, err.Error())
+			return
+		}
+
+		cliCtx = cliCtx.WithHeight(height)
+		rest.PostProcessResponse(w, cliCtx, res)
+	}
+}

x/supply/keeper/querier.go

@@ -0,0 +1,78 @@
+package keeper
+
+import (
+	"fmt"
+
+	abci "github.com/tendermint/tendermint/abci/types"
+
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/cosmos-sdk/x/supply/types"
+)
+
+// NewQuerier creates a querier for supply REST endpoints
+func NewQuerier(k Keeper) sdk.Querier {
+	return func(ctx sdk.Context, path []string, req abci.RequestQuery) (res []byte, err sdk.Error) {
+		switch path[0] {
+		case types.QueryTotalSupply:
+			return queryTotalSupply(ctx, req, k)
+		case types.QuerySupplyOf:
+			return querySupplyOf(ctx, req, k)
+		default:
+			return nil, sdk.ErrUnknownRequest("unknown supply query endpoint")
+		}
+	}
+}
+
+func queryTotalSupply(ctx sdk.Context, req abci.RequestQuery, k Keeper) ([]byte, sdk.Error) {
+	var params types.QueryTotalSupplyParams
+
+	err := types.ModuleCdc.UnmarshalJSON(req.Data, &params)
+	if err != nil {
+		return nil, sdk.ErrInternal(fmt.Sprintf("failed to parse params: %s", err))
+	}
+
+	totalSupply := k.GetSupply(ctx).Total
+	totalSupplyLen := len(totalSupply)
+
+	if params.Limit == 0 {
+		params.Limit = totalSupplyLen
+	}
+
+	start := (params.Page - 1) * params.Limit
+	end := params.Limit + start
+	if end >= totalSupplyLen {
+		end = totalSupplyLen
+	}
+
+	if start >= totalSupplyLen {
+		// page is out of bounds
+		totalSupply = sdk.Coins{}
+	} else {
+		totalSupply = totalSupply[start:end]
+	}
+
+	res, err := totalSupply.MarshalJSON()
+	if err != nil {
+		return nil, sdk.ErrInternal(sdk.AppendMsgToErr("failed to JSON marshal result: %s", err.Error()))
+	}
+
+	return res, nil
+}
+
+func querySupplyOf(ctx sdk.Context, req abci.RequestQuery, k Keeper) ([]byte, sdk.Error) {
+	var params types.QuerySupplyOfParams
+
+	err := types.ModuleCdc.UnmarshalJSON(req.Data, &params)
+	if err != nil {
+		return nil, sdk.ErrInternal(fmt.Sprintf("failed to parse params: %s", err))
+	}
+
+	supply := k.GetSupply(ctx).Total.AmountOf(params.Denom)
+
+	res, err := supply.MarshalJSON()
+	if err != nil {
+		return nil, sdk.ErrInternal(sdk.AppendMsgToErr("failed to JSON marshal result: %s", err.Error()))
+	}
+
+	return res, nil
+}