jrpc2: improve error for 'eth backend missing logs for block'

This commit also changed the block that we request for missing logs
detection. We used to request the fromBlock, but it should be to
toBlock. This was liekly not an issue because in the cases where the
provider is missing the block/logs the fromBlock == toBlock.

jrpc2/client.go

@@ -731,15 +731,17 @@ type logResp struct {
 
 func (c *Client) logs(ctx context.Context, url string, filter *glf.Filter, bm blockmap, start, limit uint64) error {
 	var (
-		t0 = time.Now()
-		lf = struct {
+		t0        = time.Now()
+		fromBlock = start
+		toBlock   = start + limit - 1
+		lf        = struct {
 			From    string     `json:"fromBlock"`
 			To      string     `json:"toBlock"`
 			Address []string   `json:"address"`
 			Topics  [][]string `json:"topics"`
 		}{
-			From:    eth.EncodeUint64(start),
-			To:      eth.EncodeUint64(start + limit - 1),
+			From:    eth.EncodeUint64(fromBlock),
+			To:      eth.EncodeUint64(toBlock),
 			Address: filter.Addresses(),
 			Topics:  filter.Topics(),
 		}
@@ -753,7 +755,7 @@ func (c *Client) logs(ctx context.Context, url string, filter *glf.Filter, bm bl
 			ID:      fmt.Sprintf("blocks-%d-%d-%x", start, limit, randbytes()),
 			Version: "2.0",
 			Method:  "eth_getBlockByNumber",
-			Params:  []any{"0x" + strconv.FormatUint(start, 16), false},
+			Params:  []any{lf.To, false},
 		},
 		request{
 			ID:      fmt.Sprintf("logs-%d-%d-%x", start, limit, randbytes()),
@@ -770,12 +772,12 @@ func (c *Client) logs(ctx context.Context, url string, filter *glf.Filter, bm bl
 		lresp = resp[1].(*logResp)
 	)
 	switch {
-	case hresp.Header == nil:
-		return fmt.Errorf("eth backend missing logs for block")
 	case hresp.Error.Exists():
 		return fmt.Errorf("rpc=eth_getLogs/eth_getBlockByNumber %w", lresp.Error)
 	case lresp.Error.Exists():
 		return fmt.Errorf("rpc=eth_getLogs %w", lresp.Error)
+	case hresp.Header == nil:
+		return fmt.Errorf("eth backend missing logs for block: %d", toBlock)
 	}
 	var logsByTx = map[key][]logResult{}
 	for i := range lresp.Result {

jrpc2/client_test.go

@@ -327,7 +327,7 @@ func TestValidate_Logs_NoBlocks(t *testing.T) {
 		_, err = c.Get(ctx, c.NextURL().String(), &glf.Filter{UseLogs: true}, 18000000, 2)
 	)
 	tc.WantErr(t, err)
-	const want = "getting logs: eth backend missing logs for block"
+	const want = "getting logs: eth backend missing logs for block: 18000001"
 	tc.WantGot(t, want, err.Error())
 }