feat: Add configurable pageSize on paginated requests (#245)

* feat(api): Add configurable page_size on paginated request.

Co-authored-by: Antoine Gelloz <antoine.gelloz@me.com>

pkg/api/controllers/account_controller.go

@@ -49,7 +49,8 @@ func (ctl *AccountController) GetAccounts(c *gin.Context) {
 			c.Query("address") != "" ||
 			len(c.QueryMap("metadata")) > 0 ||
 			c.Query("balance") != "" ||
-			c.Query("balance_operator") != "" {
+			c.Query("balance_operator") != "" ||
+			c.Query("page_size") != "" {
 			ResponseError(c, ledger.NewValidationError(
 				"no other query params can be set with 'pagination_token'"))
 			return
@@ -75,7 +76,8 @@ func (ctl *AccountController) GetAccounts(c *gin.Context) {
 			WithAddressFilter(token.AddressRegexpFilter).
 			WithBalanceFilter(token.BalanceFilter).
 			WithBalanceOperatorFilter(token.BalanceOperatorFilter).
-			WithMetadataFilter(token.MetadataFilter)
+			WithMetadataFilter(token.MetadataFilter).
+			WithPageSize(token.PageSize)
 
 	} else {
 		balance := c.Query("balance")
@@ -97,12 +99,19 @@ func (ctl *AccountController) GetAccounts(c *gin.Context) {
 			}
 		}
 
+		pageSize, err := getPageSize(c)
+		if err != nil {
+			ResponseError(c, err)
+			return
+		}
+
 		accountsQuery = storage.NewAccountsQuery().
 			WithAfterAddress(c.Query("after")).
 			WithAddressFilter(c.Query("address")).
 			WithBalanceFilter(balance).
 			WithBalanceOperatorFilter(balanceOperator).
-			WithMetadataFilter(c.QueryMap("metadata"))
+			WithMetadataFilter(c.QueryMap("metadata")).
+			WithPageSize(pageSize)
 	}
 
 	cursor, err = l.(*ledger.Ledger).GetAccounts(c.Request.Context(), *accountsQuery)

pkg/api/controllers/account_controller_test.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"encoding/base64"
 	"encoding/json"
+	"fmt"
 	"net/http"
 	"net/url"
 	"testing"
@@ -13,6 +14,7 @@ import (
 	"github.com/numary/ledger/pkg/api/controllers"
 	"github.com/numary/ledger/pkg/api/internal"
 	"github.com/numary/ledger/pkg/core"
+	"github.com/numary/ledger/pkg/storage"
 	"github.com/numary/ledger/pkg/storage/sqlstorage"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -336,6 +338,84 @@ func TestGetAccounts(t *testing.T) {
 	}))
 }
 
+func TestGetAccountsWithPageSize(t *testing.T) {
+	internal.RunTest(t, fx.Invoke(func(lc fx.Lifecycle, api *api.API, driver storage.Driver) {
+		lc.Append(fx.Hook{
+			OnStart: func(ctx context.Context) error {
+				var previousLog *core.Log
+				logs := make([]core.Log, 0)
+				store := internal.GetStore(t, driver, context.Background())
+
+				for i := 0; i < 3*controllers.MaxPageSize; i++ {
+					log := core.NewSetMetadataLog(previousLog, core.SetMetadata{
+						TargetID:   fmt.Sprintf("accounts:%06d", i),
+						TargetType: core.MetaTargetTypeAccount,
+						Metadata: map[string]json.RawMessage{
+							"foo": []byte("{}"),
+						},
+					})
+					logs = append(logs, log)
+					previousLog = &log
+				}
+				require.NoError(t, store.AppendLog(context.Background(), logs...))
+
+				t.Run("invalid page size", func(t *testing.T) {
+					rsp := internal.GetAccounts(api, url.Values{
+						"page_size": []string{"nan"},
+					})
+					assert.Equal(t, http.StatusBadRequest, rsp.Result().StatusCode, rsp.Body.String())
+
+					err := sharedapi.ErrorResponse{}
+					internal.Decode(t, rsp.Body, &err)
+					assert.EqualValues(t, sharedapi.ErrorResponse{
+						ErrorCode:    controllers.ErrValidation,
+						ErrorMessage: controllers.ErrInvalidPageSize.Error(),
+					}, err)
+				})
+				t.Run("page size over maximum", func(t *testing.T) {
+					httpResponse := internal.GetAccounts(api, url.Values{
+						"page_size": []string{fmt.Sprintf("%d", 2*controllers.MaxPageSize)},
+					})
+					assert.Equal(t, http.StatusOK, httpResponse.Result().StatusCode, httpResponse.Body.String())
+
+					cursor := internal.DecodeCursorResponse[core.Account](t, httpResponse.Body)
+					assert.Len(t, cursor.Data, controllers.MaxPageSize)
+					assert.Equal(t, cursor.PageSize, controllers.MaxPageSize)
+					assert.NotEmpty(t, cursor.Next)
+					assert.True(t, cursor.HasMore)
+				})
+				t.Run("with page size greater than max count", func(t *testing.T) {
+					httpResponse := internal.GetAccounts(api, url.Values{
+						"page_size": []string{fmt.Sprintf("%d", controllers.MaxPageSize)},
+						"after":     []string{fmt.Sprintf("accounts:%06d", controllers.MaxPageSize-100)},
+					})
+					assert.Equal(t, http.StatusOK, httpResponse.Result().StatusCode, httpResponse.Body.String())
+
+					cursor := internal.DecodeCursorResponse[core.Account](t, httpResponse.Body)
+					assert.Len(t, cursor.Data, controllers.MaxPageSize-100)
+					assert.Equal(t, controllers.MaxPageSize, cursor.PageSize)
+					assert.Empty(t, cursor.Next)
+					assert.False(t, cursor.HasMore)
+				})
+				t.Run("with page size lower than max count", func(t *testing.T) {
+					httpResponse := internal.GetAccounts(api, url.Values{
+						"page_size": []string{fmt.Sprintf("%d", controllers.MaxPageSize/10)},
+					})
+					assert.Equal(t, http.StatusOK, httpResponse.Result().StatusCode, httpResponse.Body.String())
+
+					cursor := internal.DecodeCursorResponse[core.Account](t, httpResponse.Body)
+					assert.Len(t, cursor.Data, controllers.MaxPageSize/10)
+					assert.Equal(t, cursor.PageSize, controllers.MaxPageSize/10)
+					assert.NotEmpty(t, cursor.Next)
+					assert.True(t, cursor.HasMore)
+				})
+
+				return nil
+			},
+		})
+	}))
+}
+
 func TestGetAccount(t *testing.T) {
 	internal.RunTest(t, fx.Invoke(func(lc fx.Lifecycle, api *api.API) {
 		lc.Append(fx.Hook{

pkg/api/controllers/balance_controller.go

@@ -46,7 +46,8 @@ func (ctl *BalanceController) GetBalances(c *gin.Context) {
 
 	if c.Query("pagination_token") != "" {
 		if c.Query("after") != "" ||
-			c.Query("address") != "" {
+			c.Query("address") != "" ||
+			c.Query("page_size") != "" {
 			ResponseError(c, ledger.NewValidationError(
 				"no other query params can be set with 'pagination_token'"))
 			return
@@ -69,12 +70,21 @@ func (ctl *BalanceController) GetBalances(c *gin.Context) {
 		balancesQuery = balancesQuery.
 			WithOffset(token.Offset).
 			WithAfterAddress(token.AfterAddress).
-			WithAddressFilter(token.AddressRegexpFilter)
+			WithAddressFilter(token.AddressRegexpFilter).
+			WithPageSize(token.PageSize)
 
 	} else {
+
+		pageSize, err := getPageSize(c)
+		if err != nil {
+			ResponseError(c, err)
+			return
+		}
+
 		balancesQuery = balancesQuery.
 			WithAfterAddress(c.Query("after")).
-			WithAddressFilter(c.Query("address"))
+			WithAddressFilter(c.Query("address")).
+			WithPageSize(pageSize)
 	}
 
 	cursor, err := l.(*ledger.Ledger).GetBalances(c.Request.Context(), *balancesQuery)