rpc/core: return an error if page=0 (#4947)

* rpc/core: return an error if `page=0`

Closes #4942

affected endpoints:

- /validators
- /tx_search

* swagger: update doc for /unconfirmed_txs

rpc/core/consensus.go

@@ -16,7 +16,7 @@ import (
 // for the validators in the set as used in computing their Merkle root.
 //
 // More: https://docs.tendermint.com/master/rpc/#/Info/validators
-func Validators(ctx *rpctypes.Context, heightPtr *int64, page, perPage int) (*ctypes.ResultValidators, error) {
+func Validators(ctx *rpctypes.Context, heightPtr *int64, pagePtr, perPagePtr *int) (*ctypes.ResultValidators, error) {
 	// The latest validator that we know is the NextValidator of the last block.
 	height, err := getHeight(latestUncommittedHeight(), heightPtr)
 	if err != nil {
@@ -29,8 +29,8 @@ func Validators(ctx *rpctypes.Context, heightPtr *int64, page, perPage int) (*ct
 	}
 
 	totalCount := len(validators.Validators)
-	perPage = validatePerPage(perPage)
-	page, err = validatePage(page, perPage, totalCount)
+	perPage := validatePerPage(perPagePtr)
+	page, err := validatePage(pagePtr, perPage, totalCount)
 	if err != nil {
 		return nil, err
 	}

rpc/core/env.go

@@ -92,27 +92,33 @@ type Environment struct {
 
 //----------------------------------------------
 
-func validatePage(page, perPage, totalCount int) (int, error) {
+func validatePage(pagePtr *int, perPage, totalCount int) (int, error) {
 	if perPage < 1 {
 		panic(fmt.Sprintf("zero or negative perPage: %d", perPage))
 	}
 
-	if page == 0 {
-		return 1, nil // default
+	if pagePtr == nil { // no page parameter
+		return 1, nil
 	}
 
 	pages := ((totalCount - 1) / perPage) + 1
 	if pages == 0 {
 		pages = 1 // one page (even if it's empty)
 	}
-	if page < 0 || page > pages {
-		return 1, fmt.Errorf("page should be within [0, %d] range, given %d", pages, page)
+	page := *pagePtr
+	if page <= 0 || page > pages {
+		return 1, fmt.Errorf("page should be within [1, %d] range, given %d", pages, page)
 	}
 
 	return page, nil
 }
 
-func validatePerPage(perPage int) int {
+func validatePerPage(perPagePtr *int) int {
+	if perPagePtr == nil { // no per_page parameter
+		return defaultPerPage
+	}
+
+	perPage := *perPagePtr
 	if perPage < 1 {
 		return defaultPerPage
 	} else if perPage > maxPerPage {

rpc/core/env_test.go

@@ -40,7 +40,7 @@ func TestPaginationPage(t *testing.T) {
 	}
 
 	for _, c := range cases {
-		p, err := validatePage(c.page, c.perPage, c.totalCount)
+		p, err := validatePage(&c.page, c.perPage, c.totalCount)
 		if c.expErr {
 			assert.Error(t, err)
 			continue
@@ -49,6 +49,11 @@ func TestPaginationPage(t *testing.T) {
 		assert.Equal(t, c.newPage, p, fmt.Sprintf("%v", c))
 	}
 
+	// nil case
+	p, err := validatePage(nil, 1, 1)
+	if assert.NoError(t, err) {
+		assert.Equal(t, 1, p)
+	}
 }
 
 func TestPaginationPerPage(t *testing.T) {
@@ -67,7 +72,11 @@ func TestPaginationPerPage(t *testing.T) {
 	}
 
 	for _, c := range cases {
-		p := validatePerPage(c.perPage)
+		p := validatePerPage(&c.perPage)
 		assert.Equal(t, c.newPerPage, p, fmt.Sprintf("%v", c))
 	}
+
+	// nil case
+	p := validatePerPage(nil)
+	assert.Equal(t, defaultPerPage, p)
 }

rpc/core/mempool.go

@@ -130,9 +130,9 @@ func BroadcastTxCommit(ctx *rpctypes.Context, tx types.Tx) (*ctypes.ResultBroadc
 // UnconfirmedTxs gets unconfirmed transactions (maximum ?limit entries)
 // including their number.
 // More: https://docs.tendermint.com/master/rpc/#/Info/unconfirmed_txs
-func UnconfirmedTxs(ctx *rpctypes.Context, limit int) (*ctypes.ResultUnconfirmedTxs, error) {
+func UnconfirmedTxs(ctx *rpctypes.Context, limitPtr *int) (*ctypes.ResultUnconfirmedTxs, error) {
 	// reuse per_page validator
-	limit = validatePerPage(limit)
+	limit := validatePerPage(limitPtr)
 
 	txs := env.Mempool.ReapMaxTxs(limit)
 	return &ctypes.ResultUnconfirmedTxs{

rpc/core/tx.go

@@ -54,7 +54,7 @@ func Tx(ctx *rpctypes.Context, hash []byte, prove bool) (*ctypes.ResultTx, error
 // TxSearch allows you to query for multiple transactions results. It returns a
 // list of transactions (maximum ?per_page entries) and the total count.
 // More: https://docs.tendermint.com/master/rpc/#/Info/tx_search
-func TxSearch(ctx *rpctypes.Context, query string, prove bool, page, perPage int, orderBy string) (
+func TxSearch(ctx *rpctypes.Context, query string, prove bool, pagePtr, perPagePtr *int, orderBy string) (
 	*ctypes.ResultTxSearch, error) {
 	// if index is disabled, return error
 	if _, ok := env.TxIndexer.(*null.TxIndex); ok {
@@ -93,8 +93,8 @@ func TxSearch(ctx *rpctypes.Context, query string, prove bool, page, perPage int
 
 	// paginate results
 	totalCount := len(results)
-	perPage = validatePerPage(perPage)
-	page, err = validatePage(page, perPage, totalCount)
+	perPage := validatePerPage(perPagePtr)
+	page, err := validatePage(pagePtr, perPage, totalCount)
 	if err != nil {
 		return nil, err
 	}