Graceful service degradation: block page (#1541)

* display main data

* display rest of tx fields

* placeholder data

* always show tabs

* manage error and retries on details tab

* don't retry if degraded view is active

* fix tests

* fix tx receipt

* change styles and wording for warning

* tweaks

* gray alert style change and update screenshots

* display main block info from RPC

* refetch API query

* txs tab

* display empty address for contract creation tx

* withdrawals tab

* remove type coercions

* lazy rendered lists

* fix RPC query refetch

* fixes

* comment about block type

* fix tests

* update screenshots

* [skip ci] better variable name

configs/envs/.env.eth_goerli

@@ -49,8 +49,9 @@ NEXT_PUBLIC_ADMIN_SERVICE_API_HOST=https://admin-rs.services.blockscout.com
 NEXT_PUBLIC_NAME_SERVICE_API_HOST=https://bens-rs-test.k8s-dev.blockscout.com
 NEXT_PUBLIC_WEB3_WALLETS=['token_pocket','metamask']
 NEXT_PUBLIC_VIEWS_CONTRACT_SOLIDITYSCAN_ENABLED='true'
+NEXT_PUBLIC_HAS_BEACON_CHAIN=true
+NEXT_PUBLIC_HAS_USER_OPS=true
 NEXT_PUBLIC_CONTRACT_CODE_IDES=[{'title':'Remix IDE','url':'https://remix.blockscout.com/?address={hash}&blockscout=eth-goerli.blockscout.com','icon_url':'https://raw.githubusercontent.com/blockscout/frontend-configs/main/configs/ide-icons/remix.png'}]
-NEXT_PUBLIC_HAS_USER_OPS='true'
 
 #meta
 NEXT_PUBLIC_OG_IMAGE_URL=https://github.com/blockscout/frontend-configs/blob/main/configs/og-images/eth-goerli.png?raw=true

lib/hooks/useLazyRenderedList.tsx

+import _clamp from 'lodash/clamp';
+import React from 'react';
+import { useInView } from 'react-intersection-observer';
+
+const STEP = 10;
+const MIN_ITEMS_NUM = 50;
+
+export default function useLazyRenderedList(list: Array<unknown>, isEnabled: boolean) {
+  const [ renderedItemsNum, setRenderedItemsNum ] = React.useState(MIN_ITEMS_NUM);
+  const { ref, inView } = useInView({
+    rootMargin: '200px',
+    triggerOnce: false,
+    skip: !isEnabled || list.length <= MIN_ITEMS_NUM,
+  });
+
+  React.useEffect(() => {
+    if (inView) {
+      setRenderedItemsNum((prev) => _clamp(prev + STEP, 0, list.length));
+    }
+  }, [ inView, list.length ]);
+
+  return { cutRef: ref, renderedItemsNum };
+}

stubs/RPC.ts

-import type { Chain, GetBlockReturnType, GetTransactionReturnType, TransactionReceipt } from 'viem';
+import type { Chain, GetBlockReturnType, GetTransactionReturnType, TransactionReceipt, Withdrawal } from 'viem';
 
 import { ADDRESS_HASH } from './addressParams';
 import { BLOCK_HASH } from './block';
 import { TX_HASH } from './tx';
 
+export const WITHDRAWAL: Withdrawal = {
+  index: '0x1af95d9',
+  validatorIndex: '0x7d748',
+  address: '0x9b52b9033ecbb6635f1c31a646d5691b282878aa',
+  amount: '0x29e16b',
+};
+
 export const GET_TRANSACTION: GetTransactionReturnType<Chain, 'latest'> = {
   blockHash: BLOCK_HASH,
   blockNumber: BigInt(10361367),
@@ -70,7 +77,12 @@ export const GET_BLOCK: GetBlockReturnType<Chain, false, 'latest'> = {
   ],
   transactionsRoot: TX_HASH,
   uncles: [],
-  withdrawals: [ ],
+  withdrawals: Array(10).fill(WITHDRAWAL),
   withdrawalsRoot: TX_HASH,
   sealFields: [ '0x00' ],
 };
+
+export const GET_BLOCK_WITH_TRANSACTIONS: GetBlockReturnType<Chain, true, 'latest'> = {
+  ...GET_BLOCK,
+  transactions: Array(50).fill(GET_TRANSACTION),
+};

types/api/block.ts

@@ -13,7 +13,7 @@ export interface Block {
   hash: string;
   parent_hash: string;
   difficulty: string;
-  total_difficulty: string;
+  total_difficulty: string | null;
   gas_used: string | null;
   gas_limit: string;
   nonce: string;
@@ -69,7 +69,7 @@ export type BlockWithdrawalsResponse = {
   next_page_params: {
     index: number;
     items_count: number;
-  };
+  } | null;
 }
 
 export type BlockWithdrawalsItem = {

types/api/transaction.ts

@@ -26,7 +26,7 @@ export type Transaction = {
   hash: string;
   result: string;
   confirmations: number;
-  status: 'ok' | 'error' | null;
+  status: 'ok' | 'error' | null | undefined;
   block: number | null;
   timestamp: string | null;
   confirmation_duration: Array<number> | null;

ui/block/BlockDetails.pw.tsx

 import { test, expect } from '@playwright/experimental-ct-react';
-import type { UseQueryResult } from '@tanstack/react-query';
 import React from 'react';
 
-import type { Block } from 'types/api/block';
-
-import type { ResourceError } from 'lib/api/resources';
 import * as blockMock from 'mocks/blocks/block';
 import contextWithEnvs from 'playwright/fixtures/contextWithEnvs';
 import TestApp from 'playwright/TestApp';
 import * as configs from 'playwright/utils/configs';
 
 import BlockDetails from './BlockDetails';
+import type { BlockQuery } from './useBlockQuery';
 
 const hooksConfig = {
   router: {
@@ -22,7 +19,7 @@ test('regular block +@mobile +@dark-mode', async({ mount, page }) => {
   const query = {
     data: blockMock.base,
     isPending: false,
-  } as UseQueryResult<Block, ResourceError>;
+  } as BlockQuery;
 
   const component = await mount(
     <TestApp>
@@ -40,7 +37,7 @@ test('genesis block', async({ mount, page }) => {
   const query = {
     data: blockMock.genesis,
     isPending: false,
-  } as UseQueryResult<Block, ResourceError>;
+  } as BlockQuery;
 
   const component = await mount(
     <TestApp>
@@ -63,7 +60,7 @@ customFieldsTest('rootstock custom fields', async({ mount, page }) => {
   const query = {
     data: blockMock.rootstock,
     isPending: false,
-  } as UseQueryResult<Block, ResourceError>;
+  } as BlockQuery;
 
   const component = await mount(
     <TestApp>

ui/block/BlockDetails.tsx

 import { Grid, GridItem, Text, Link, Box, Tooltip, useColorModeValue, Skeleton } from '@chakra-ui/react';
-import type { UseQueryResult } from '@tanstack/react-query';
 import BigNumber from 'bignumber.js';
 import capitalize from 'lodash/capitalize';
 import { useRouter } from 'next/router';
 import React from 'react';
 import { scroller, Element } from 'react-scroll';
 
-import type { Block } from 'types/api/block';
-
 import { route } from 'nextjs-routes';
 
 import config from 'configs/app';
-import type { ResourceError } from 'lib/api/resources';
 import getBlockReward from 'lib/block/getBlockReward';
 import { GWEI, WEI, WEI_IN_GWEI, ZERO } from 'lib/consts';
-import throwOnResourceLoadError from 'lib/errors/throwOnResourceLoadError';
 import { space } from 'lib/html-entities';
 import getNetworkValidatorTitle from 'lib/networks/getNetworkValidatorTitle';
 import getQueryParamString from 'lib/router/getQueryParamString';
 import { currencyUnits } from 'lib/units';
 import CopyToClipboard from 'ui/shared/CopyToClipboard';
-import DataFetchAlert from 'ui/shared/DataFetchAlert';
 import DetailsInfoItem from 'ui/shared/DetailsInfoItem';
 import DetailsInfoItemDivider from 'ui/shared/DetailsInfoItemDivider';
 import DetailsTimestamp from 'ui/shared/DetailsTimestamp';
@@ -34,8 +28,10 @@ import RawDataSnippet from 'ui/shared/RawDataSnippet';
 import TextSeparator from 'ui/shared/TextSeparator';
 import Utilization from 'ui/shared/Utilization/Utilization';
 
+import type { BlockQuery } from './useBlockQuery';
+
 interface Props {
-  query: UseQueryResult<Block, ResourceError>;
+  query: BlockQuery;
 }
 
 const isRollup = config.features.optimisticRollup.isEnabled || config.features.zkEvmRollup.isEnabled;
@@ -47,7 +43,7 @@ const BlockDetails = ({ query }: Props) => {
 
   const separatorColor = useColorModeValue('gray.200', 'gray.700');
 
-  const { data, isPlaceholderData, isError, error } = query;
+  const { data, isPlaceholderData } = query;
 
   const handleCutClick = React.useCallback(() => {
     setIsExpanded((flag) => !flag);
@@ -68,14 +64,6 @@ const BlockDetails = ({ query }: Props) => {
     router.push({ pathname: '/block/[height_or_hash]', query: { height_or_hash: nextId } }, undefined);
   }, [ data, router ]);
 
-  if (isError) {
-    if (error?.status === 404 || error?.status === 422) {
-      throwOnResourceLoadError({ isError, error });
-    }
-
-    return <DataFetchAlert/>;
-  }
-
   if (!data) {
     return null;
   }
@@ -308,7 +296,7 @@ const BlockDetails = ({ query }: Props) => {
           ) }
         </DetailsInfoItem>
       ) }
-      { !config.UI.views.block.hiddenFields?.burnt_fees && (
+      { !config.UI.views.block.hiddenFields?.burnt_fees && !burntFees.isEqualTo(ZERO) && (
         <DetailsInfoItem
           title="Burnt fees"
           hint={
@@ -437,14 +425,16 @@ const BlockDetails = ({ query }: Props) => {
               <HashStringShortenDynamic hash={ BigNumber(data.difficulty).toFormat() }/>
             </Box>
           </DetailsInfoItem>
-          <DetailsInfoItem
-            title="Total difficulty"
-            hint="Total difficulty of the chain until this block"
-          >
-            <Box whiteSpace="nowrap" overflow="hidden">
-              <HashStringShortenDynamic hash={ BigNumber(data.total_difficulty).toFormat() }/>
-            </Box>
-          </DetailsInfoItem>
+          { data.total_difficulty && (
+            <DetailsInfoItem
+              title="Total difficulty"
+              hint="Total difficulty of the chain until this block"
+            >
+              <Box whiteSpace="nowrap" overflow="hidden">
+                <HashStringShortenDynamic hash={ BigNumber(data.total_difficulty).toFormat() }/>
+              </Box>
+            </DetailsInfoItem>
+          ) }
 
           <DetailsInfoItemDivider/>
 

ui/block/BlockWithdrawals.tsx

@@ -3,7 +3,7 @@ import React from 'react';
 
 import DataListDisplay from 'ui/shared/DataListDisplay';
 import type { QueryWithPagesResult } from 'ui/shared/pagination/useQueryWithPages';
-import WithdrawalsListItem from 'ui/withdrawals/WithdrawalsListItem';
+import WithdrawalsList from 'ui/withdrawals/WithdrawalsList';
 import WithdrawalsTable from 'ui/withdrawals/WithdrawalsTable';
 
 type Props = {
@@ -14,14 +14,11 @@ const BlockWithdrawals = ({ blockWithdrawalsQuery }: Props) => {
   const content = blockWithdrawalsQuery.data?.items ? (
     <>
       <Show below="lg" ssr={ false }>
-        { blockWithdrawalsQuery.data.items.map((item, index) => (
-          <WithdrawalsListItem
-            key={ item.index + (blockWithdrawalsQuery.isPlaceholderData ? String(index) : '') }
-            item={ item }
-            view="block"
-            isLoading={ blockWithdrawalsQuery.isPlaceholderData }
-          />
-        )) }
+        <WithdrawalsList
+          items={ blockWithdrawalsQuery.data.items }
+          isLoading={ blockWithdrawalsQuery.isPlaceholderData }
+          view="block"
+        />
       </Show>
       <Hide below="lg" ssr={ false }>
         <WithdrawalsTable

ui/block/useBlockQuery.tsx

+import type { UseQueryResult } from '@tanstack/react-query';
+import { useQuery } from '@tanstack/react-query';
+import React from 'react';
+import type { Chain, GetBlockReturnType } from 'viem';
+
+import type { Block } from 'types/api/block';
+
+import type { ResourceError } from 'lib/api/resources';
+import useApiQuery from 'lib/api/useApiQuery';
+import { retry } from 'lib/api/useQueryClientConfig';
+import { SECOND } from 'lib/consts';
+import dayjs from 'lib/date/dayjs';
+import { publicClient } from 'lib/web3/client';
+import { BLOCK } from 'stubs/block';
+import { GET_BLOCK } from 'stubs/RPC';
+import { unknownAddress } from 'ui/shared/address/utils';
+
+type RpcResponseType = GetBlockReturnType<Chain, false, 'latest'> | null;
+
+export type BlockQuery = UseQueryResult<Block, ResourceError<{ status: number }>> & {
+  isDegradedData: boolean;
+};
+
+interface Params {
+  heightOrHash: string;
+}
+
+export default function useBlockQuery({ heightOrHash }: Params): BlockQuery {
+  const [ isRefetchEnabled, setRefetchEnabled ] = React.useState(false);
+
+  const apiQuery = useApiQuery<'block', { status: number }>('block', {
+    pathParams: { height_or_hash: heightOrHash },
+    queryOptions: {
+      enabled: Boolean(heightOrHash),
+      placeholderData: BLOCK,
+      refetchOnMount: false,
+      retry: (failureCount, error) => {
+        if (isRefetchEnabled) {
+          return false;
+        }
+
+        return retry(failureCount, error);
+      },
+      refetchInterval: (): number | false => {
+        return isRefetchEnabled ? 15 * SECOND : false;
+      },
+    },
+  });
+
+  const rpcQuery = useQuery<RpcResponseType, unknown, Block | null>({
+    queryKey: [ 'RPC', 'block', { heightOrHash } ],
+    queryFn: async() => {
+      const blockParams = heightOrHash.startsWith('0x') ? { blockHash: heightOrHash as `0x${ string }` } : { blockNumber: BigInt(heightOrHash) };
+      return publicClient.getBlock(blockParams).catch(() => null);
+    },
+    select: (block) => {
+      if (!block) {
+        return null;
+      }
+
+      return {
+        height: Number(block.number),
+        timestamp: dayjs.unix(Number(block.timestamp)).format(),
+        tx_count: block.transactions.length,
+        miner: { ...unknownAddress, hash: block.miner },
+        size: Number(block.size),
+        hash: block.hash,
+        parent_hash: block.parentHash,
+        difficulty: block.difficulty.toString(),
+        total_difficulty: block.totalDifficulty?.toString() ?? null,
+        gas_used: block.gasUsed.toString(),
+        gas_limit: block.gasLimit.toString(),
+        nonce: block.nonce,
+        base_fee_per_gas: block.baseFeePerGas?.toString() ?? null,
+        burnt_fees: null,
+        priority_fee: null,
+        extra_data: block.extraData,
+        state_root: block.stateRoot,
+        gas_target_percentage: null,
+        gas_used_percentage: null,
+        burnt_fees_percentage: null,
+        type: 'block', // we can't get this type from RPC, so it will always be a regular block
+        tx_fees: null,
+        uncles_hashes: block.uncles,
+        withdrawals_count: block.withdrawals?.length,
+      };
+    },
+    placeholderData: GET_BLOCK,
+    enabled: apiQuery.isError || apiQuery.errorUpdateCount > 0,
+    retry: false,
+    refetchOnMount: false,
+  });
+
+  React.useEffect(() => {
+    if (apiQuery.isPlaceholderData) {
+      return;
+    }
+
+    if (apiQuery.isError && apiQuery.errorUpdateCount === 1) {
+      setRefetchEnabled(true);
+    } else if (!apiQuery.isError) {
+      setRefetchEnabled(false);
+    }
+  }, [ apiQuery.errorUpdateCount, apiQuery.isError, apiQuery.isPlaceholderData ]);
+
+  React.useEffect(() => {
+    if (!rpcQuery.isPlaceholderData && !rpcQuery.data) {
+      setRefetchEnabled(false);
+    }
+  }, [ rpcQuery.data, rpcQuery.isPlaceholderData ]);
+
+  const isRpcQuery = Boolean((apiQuery.isError || apiQuery.isPlaceholderData) && apiQuery.errorUpdateCount > 0 && rpcQuery.data);
+  const query = isRpcQuery ? rpcQuery as UseQueryResult<Block, ResourceError<{ status: number }>> : apiQuery;
+
+  return {
+    ...query,
+    isDegradedData: isRpcQuery,
+  };
+}

ui/block/useBlockTxQuery.tsx

+import type { UseQueryResult } from '@tanstack/react-query';
+import { useQuery } from '@tanstack/react-query';
+import React from 'react';
+import type { Chain, GetBlockReturnType } from 'viem';
+
+import type { BlockTransactionsResponse } from 'types/api/block';
+
+import type { ResourceError } from 'lib/api/resources';
+import { retry } from 'lib/api/useQueryClientConfig';
+import { SECOND } from 'lib/consts';
+import dayjs from 'lib/date/dayjs';
+import hexToDecimal from 'lib/hexToDecimal';
+import { publicClient } from 'lib/web3/client';
+import { GET_BLOCK_WITH_TRANSACTIONS } from 'stubs/RPC';
+import { TX } from 'stubs/tx';
+import { generateListStub } from 'stubs/utils';
+import { unknownAddress } from 'ui/shared/address/utils';
+import type { QueryWithPagesResult } from 'ui/shared/pagination/useQueryWithPages';
+import useQueryWithPages from 'ui/shared/pagination/useQueryWithPages';
+import { emptyPagination } from 'ui/shared/pagination/utils';
+
+import type { BlockQuery } from './useBlockQuery';
+
+type RpcResponseType = GetBlockReturnType<Chain, boolean, 'latest'> | null;
+
+export type BlockTxsQuery = QueryWithPagesResult<'block_txs'> & {
+  isDegradedData: boolean;
+};
+
+interface Params {
+  heightOrHash: string;
+  blockQuery: BlockQuery;
+  tab: string;
+}
+
+export default function useBlockTxQuery({ heightOrHash, blockQuery, tab }: Params): BlockTxsQuery {
+  const [ isRefetchEnabled, setRefetchEnabled ] = React.useState(false);
+
+  const apiQuery = useQueryWithPages({
+    resourceName: 'block_txs',
+    pathParams: { height_or_hash: heightOrHash },
+    options: {
+      enabled: Boolean(tab === 'txs' && !blockQuery.isPlaceholderData && !blockQuery.isDegradedData),
+      placeholderData: generateListStub<'block_txs'>(TX, 50, { next_page_params: {
+        block_number: 9004925,
+        index: 49,
+        items_count: 50,
+      } }),
+      refetchOnMount: false,
+      retry: (failureCount, error) => {
+        if (isRefetchEnabled) {
+          return false;
+        }
+
+        return retry(failureCount, error);
+      },
+      refetchInterval: (): number | false => {
+        return isRefetchEnabled ? 15 * SECOND : false;
+      },
+    },
+  });
+
+  const rpcQuery = useQuery<RpcResponseType, unknown, BlockTransactionsResponse | null>({
+    queryKey: [ 'RPC', 'block_txs', { heightOrHash } ],
+    queryFn: async() => {
+      const blockParams = heightOrHash.startsWith('0x') ?
+        { blockHash: heightOrHash as `0x${ string }`, includeTransactions: true } :
+        { blockNumber: BigInt(heightOrHash), includeTransactions: true };
+      return publicClient.getBlock(blockParams).catch(() => null);
+    },
+    select: (block) => {
+      if (!block) {
+        return null;
+      }
+
+      return {
+        items: block.transactions
+          .map((tx) => {
+            if (typeof tx === 'string') {
+              return;
+            }
+
+            return {
+              from: { ...unknownAddress, hash: tx.from as string },
+              to: tx.to ? { ...unknownAddress, hash: tx.to as string } : null,
+              hash: tx.hash as string,
+              timestamp: block?.timestamp ? dayjs.unix(Number(block.timestamp)).format() : null,
+              confirmation_duration: null,
+              status: undefined,
+              block: Number(block.number),
+              value: tx.value.toString(),
+              gas_price: tx.gasPrice?.toString() ?? null,
+              base_fee_per_gas: block?.baseFeePerGas?.toString() ?? null,
+              max_fee_per_gas: tx.maxFeePerGas?.toString() ?? null,
+              max_priority_fee_per_gas: tx.maxPriorityFeePerGas?.toString() ?? null,
+              nonce: tx.nonce,
+              position: tx.transactionIndex,
+              type: tx.typeHex ? hexToDecimal(tx.typeHex) : null,
+              raw_input: tx.input,
+              gas_used: null,
+              gas_limit: tx.gas.toString(),
+              confirmations: 0,
+              fee: {
+                value: null,
+                type: 'actual',
+              },
+              created_contract: null,
+              result: '',
+              priority_fee: null,
+              tx_burnt_fee: null,
+              revert_reason: null,
+              decoded_input: null,
+              has_error_in_internal_txs: null,
+              token_transfers: null,
+              token_transfers_overflow: false,
+              exchange_rate: null,
+              method: null,
+              tx_types: [],
+              tx_tag: null,
+              actions: [],
+            };
+          })
+          .filter(Boolean),
+        next_page_params: null,
+      };
+    },
+    placeholderData: GET_BLOCK_WITH_TRANSACTIONS,
+    enabled: tab === 'txs' && (blockQuery.isDegradedData || apiQuery.isError || apiQuery.errorUpdateCount > 0),
+    retry: false,
+    refetchOnMount: false,
+  });
+
+  React.useEffect(() => {
+    if (apiQuery.isPlaceholderData) {
+      return;
+    }
+
+    if (apiQuery.isError && apiQuery.errorUpdateCount === 1) {
+      setRefetchEnabled(true);
+    } else if (!apiQuery.isError) {
+      setRefetchEnabled(false);
+    }
+  }, [ apiQuery.errorUpdateCount, apiQuery.isError, apiQuery.isPlaceholderData ]);
+
+  React.useEffect(() => {
+    if (!rpcQuery.isPlaceholderData && !rpcQuery.data) {
+      setRefetchEnabled(false);
+    }
+  }, [ rpcQuery.data, rpcQuery.isPlaceholderData ]);
+
+  const isRpcQuery = Boolean((
+    blockQuery.isDegradedData ||
+    ((apiQuery.isError || apiQuery.isPlaceholderData) && apiQuery.errorUpdateCount > 0)
+  ) && rpcQuery.data);
+
+  const rpcQueryWithPages: QueryWithPagesResult<'block_txs'> = React.useMemo(() => {
+    return {
+      ...rpcQuery as UseQueryResult<BlockTransactionsResponse, ResourceError>,
+      pagination: emptyPagination,
+      onFilterChange: () => {},
+      onSortingChange: () => {},
+    };
+  }, [ rpcQuery ]);
+
+  const query = isRpcQuery ? rpcQueryWithPages : apiQuery;
+
+  return {
+    ...query,
+    isDegradedData: isRpcQuery,
+  };
+}

ui/block/useBlockWithdrawalsQuery.tsx

+import type { UseQueryResult } from '@tanstack/react-query';
+import { useQuery } from '@tanstack/react-query';
+import React from 'react';
+import type { Chain, GetBlockReturnType } from 'viem';
+
+import type { BlockWithdrawalsResponse } from 'types/api/block';
+
+import config from 'configs/app';
+import type { ResourceError } from 'lib/api/resources';
+import { retry } from 'lib/api/useQueryClientConfig';
+import { SECOND } from 'lib/consts';
+import hexToDecimal from 'lib/hexToDecimal';
+import { publicClient } from 'lib/web3/client';
+import { GET_BLOCK } from 'stubs/RPC';
+import { generateListStub } from 'stubs/utils';
+import { WITHDRAWAL } from 'stubs/withdrawals';
+import { unknownAddress } from 'ui/shared/address/utils';
+import type { QueryWithPagesResult } from 'ui/shared/pagination/useQueryWithPages';
+import useQueryWithPages from 'ui/shared/pagination/useQueryWithPages';
+import { emptyPagination } from 'ui/shared/pagination/utils';
+
+import type { BlockQuery } from './useBlockQuery';
+
+type RpcResponseType = GetBlockReturnType<Chain, false, 'latest'> | null;
+
+export type BlockWithdrawalsQuery = QueryWithPagesResult<'block_withdrawals'> & {
+  isDegradedData: boolean;
+};
+
+interface Params {
+  heightOrHash: string;
+  blockQuery: BlockQuery;
+  tab: string;
+}
+
+export default function useBlockWithdrawalsQuery({ heightOrHash, blockQuery, tab }: Params): BlockWithdrawalsQuery {
+  const [ isRefetchEnabled, setRefetchEnabled ] = React.useState(false);
+
+  const apiQuery = useQueryWithPages({
+    resourceName: 'block_withdrawals',
+    pathParams: { height_or_hash: heightOrHash },
+    options: {
+      enabled:
+        tab === 'withdrawals' &&
+        config.features.beaconChain.isEnabled &&
+        !blockQuery.isPlaceholderData && !blockQuery.isDegradedData,
+      placeholderData: generateListStub<'block_withdrawals'>(WITHDRAWAL, 50, { next_page_params: {
+        index: 5,
+        items_count: 50,
+      } }),
+      refetchOnMount: false,
+      retry: (failureCount, error) => {
+        if (isRefetchEnabled) {
+          return false;
+        }
+
+        return retry(failureCount, error);
+      },
+      refetchInterval: (): number | false => {
+        return isRefetchEnabled ? 15 * SECOND : false;
+      },
+    },
+  });
+
+  const rpcQuery = useQuery<RpcResponseType, unknown, BlockWithdrawalsResponse | null>({
+    queryKey: [ 'RPC', 'block', { heightOrHash } ],
+    queryFn: async() => {
+      const blockParams = heightOrHash.startsWith('0x') ? { blockHash: heightOrHash as `0x${ string }` } : { blockNumber: BigInt(heightOrHash) };
+      return publicClient.getBlock(blockParams).catch(() => null);
+    },
+    select: (block) => {
+      if (!block) {
+        return null;
+      }
+
+      return {
+        items: block.withdrawals
+          ?.map((withdrawal) => {
+            return {
+              amount: hexToDecimal(withdrawal.amount).toString(),
+              index: hexToDecimal(withdrawal.index),
+              validator_index: hexToDecimal(withdrawal.validatorIndex),
+              receiver: { ...unknownAddress, hash: withdrawal.address },
+            };
+          })
+          .sort((a, b) => b.index - a.index) ?? [],
+        next_page_params: null,
+      };
+    },
+    placeholderData: GET_BLOCK,
+    enabled:
+      tab === 'withdrawals' &&
+      config.features.beaconChain.isEnabled &&
+      (blockQuery.isDegradedData || apiQuery.isError || apiQuery.errorUpdateCount > 0),
+    retry: false,
+    refetchOnMount: false,
+  });
+
+  React.useEffect(() => {
+    if (apiQuery.isPlaceholderData) {
+      return;
+    }
+
+    if (apiQuery.isError && apiQuery.errorUpdateCount === 1) {
+      setRefetchEnabled(true);
+    } else if (!apiQuery.isError) {
+      setRefetchEnabled(false);
+    }
+  }, [ apiQuery.errorUpdateCount, apiQuery.isError, apiQuery.isPlaceholderData ]);
+
+  React.useEffect(() => {
+    if (!rpcQuery.isPlaceholderData && !rpcQuery.data) {
+      setRefetchEnabled(false);
+    }
+  }, [ rpcQuery.data, rpcQuery.isPlaceholderData ]);
+
+  const isRpcQuery = Boolean((
+    blockQuery.isDegradedData ||
+    ((apiQuery.isError || apiQuery.isPlaceholderData) && apiQuery.errorUpdateCount > 0)
+  ) && rpcQuery.data);
+
+  const rpcQueryWithPages: QueryWithPagesResult<'block_withdrawals'> = React.useMemo(() => {
+    return {
+      ...rpcQuery as UseQueryResult<BlockWithdrawalsResponse, ResourceError>,
+      pagination: emptyPagination,
+      onFilterChange: () => {},
+      onSortingChange: () => {},
+    };
+  }, [ rpcQuery ]);
+
+  const query = isRpcQuery ? rpcQueryWithPages : apiQuery;
+
+  return {
+    ...query,
+    isDegradedData: isRpcQuery,
+  };
+}

ui/pages/Block.tsx

@@ -6,24 +6,22 @@ import type { PaginationParams } from 'ui/shared/pagination/types';
 import type { RoutedTab } from 'ui/shared/Tabs/types';
 
 import config from 'configs/app';
-import useApiQuery from 'lib/api/useApiQuery';
 import { useAppContext } from 'lib/contexts/app';
 import throwOnAbsentParamError from 'lib/errors/throwOnAbsentParamError';
 import throwOnResourceLoadError from 'lib/errors/throwOnResourceLoadError';
 import useIsMobile from 'lib/hooks/useIsMobile';
 import getQueryParamString from 'lib/router/getQueryParamString';
-import { BLOCK } from 'stubs/block';
-import { TX } from 'stubs/tx';
-import { generateListStub } from 'stubs/utils';
-import { WITHDRAWAL } from 'stubs/withdrawals';
 import BlockDetails from 'ui/block/BlockDetails';
 import BlockWithdrawals from 'ui/block/BlockWithdrawals';
+import useBlockQuery from 'ui/block/useBlockQuery';
+import useBlockTxQuery from 'ui/block/useBlockTxQuery';
+import useBlockWithdrawalsQuery from 'ui/block/useBlockWithdrawalsQuery';
 import TextAd from 'ui/shared/ad/TextAd';
+import ServiceDegradationWarning from 'ui/shared/alerts/ServiceDegradationWarning';
 import AddressEntity from 'ui/shared/entities/address/AddressEntity';
 import NetworkExplorers from 'ui/shared/NetworkExplorers';
 import PageTitle from 'ui/shared/Page/PageTitle';
 import Pagination from 'ui/shared/pagination/Pagination';
-import useQueryWithPages from 'ui/shared/pagination/useQueryWithPages';
 import RoutedTabs from 'ui/shared/Tabs/RoutedTabs';
 import TabsSkeleton from 'ui/shared/Tabs/TabsSkeleton';
 import TxsWithFrontendSorting from 'ui/txs/TxsWithFrontendSorting';
@@ -41,45 +39,42 @@ const BlockPageContent = () => {
   const heightOrHash = getQueryParamString(router.query.height_or_hash);
   const tab = getQueryParamString(router.query.tab);
 
-  const blockQuery = useApiQuery('block', {
-    pathParams: { height_or_hash: heightOrHash },
-    queryOptions: {
-      enabled: Boolean(heightOrHash),
-      placeholderData: BLOCK,
-    },
-  });
-
-  const blockTxsQuery = useQueryWithPages({
-    resourceName: 'block_txs',
-    pathParams: { height_or_hash: heightOrHash },
-    options: {
-      enabled: Boolean(!blockQuery.isPlaceholderData && blockQuery.data?.height && tab === 'txs'),
-      placeholderData: generateListStub<'block_txs'>(TX, 50, { next_page_params: {
-        block_number: 9004925,
-        index: 49,
-        items_count: 50,
-      } }),
-    },
-  });
-
-  const blockWithdrawalsQuery = useQueryWithPages({
-    resourceName: 'block_withdrawals',
-    pathParams: { height_or_hash: heightOrHash },
-    options: {
-      enabled: Boolean(!blockQuery.isPlaceholderData && blockQuery.data?.height && config.features.beaconChain.isEnabled && tab === 'withdrawals'),
-      placeholderData: generateListStub<'block_withdrawals'>(WITHDRAWAL, 50, { next_page_params: {
-        index: 5,
-        items_count: 50,
-      } }),
-    },
-  });
+  const blockQuery = useBlockQuery({ heightOrHash });
+  const blockTxsQuery = useBlockTxQuery({ heightOrHash, blockQuery, tab });
+  const blockWithdrawalsQuery = useBlockWithdrawalsQuery({ heightOrHash, blockQuery, tab });
 
   const tabs: Array<RoutedTab> = React.useMemo(() => ([
-    { id: 'index', title: 'Details', component: <BlockDetails query={ blockQuery }/> },
-    { id: 'txs', title: 'Transactions', component: <TxsWithFrontendSorting query={ blockTxsQuery } showBlockInfo={ false } showSocketInfo={ false }/> },
+    {
+      id: 'index',
+      title: 'Details',
+      component: (
+        <>
+          { blockQuery.isDegradedData && <ServiceDegradationWarning isLoading={ blockQuery.isPlaceholderData } mb={ 6 }/> }
+          <BlockDetails query={ blockQuery }/>
+        </>
+      ),
+    },
+    {
+      id: 'txs',
+      title: 'Transactions',
+      component: (
+        <>
+          { blockTxsQuery.isDegradedData && <ServiceDegradationWarning isLoading={ blockTxsQuery.isPlaceholderData } mb={ 6 }/> }
+          <TxsWithFrontendSorting query={ blockTxsQuery } showBlockInfo={ false } showSocketInfo={ false }/>
+        </>
+      ),
+    },
     config.features.beaconChain.isEnabled && Boolean(blockQuery.data?.withdrawals_count) ?
-      { id: 'withdrawals', title: 'Withdrawals', component: <BlockWithdrawals blockWithdrawalsQuery={ blockWithdrawalsQuery }/> } :
-      null,
+      {
+        id: 'withdrawals',
+        title: 'Withdrawals',
+        component: (
+          <>
+            { blockWithdrawalsQuery.isDegradedData && <ServiceDegradationWarning isLoading={ blockWithdrawalsQuery.isPlaceholderData } mb={ 6 }/> }
+            <BlockWithdrawals blockWithdrawalsQuery={ blockWithdrawalsQuery }/>
+          </>
+        ),
+      } : null,
   ].filter(Boolean)), [ blockQuery, blockTxsQuery, blockWithdrawalsQuery ]);
 
   const hasPagination = !isMobile && (

ui/shared/address/AddressFromTo.tsx

@@ -57,7 +57,7 @@ const AddressFromTo = ({ from, to, current, mode: modeProp, className, isLoading
             w="min-content"
           />
         </Flex>
-        { to ? (
+        { to && (
           <Entity
             address={ to }
             isLoading={ isLoading }
@@ -70,7 +70,7 @@ const AddressFromTo = ({ from, to, current, mode: modeProp, className, isLoading
             w="min-content"
             ml="28px"
           />
-        ) : <span>-</span> }
+        ) }
       </Flex>
     );
   }
@@ -95,7 +95,7 @@ const AddressFromTo = ({ from, to, current, mode: modeProp, className, isLoading
         isLoading={ isLoading }
         type={ getTxCourseType(from.hash, to?.hash, current) }
       />
-      { to ? (
+      { to && (
         <Entity
           address={ to }
           isLoading={ isLoading }
@@ -107,7 +107,7 @@ const AddressFromTo = ({ from, to, current, mode: modeProp, className, isLoading
           maxW={ truncation === 'constant' ? undefined : `calc(50% - ${ iconSizeWithMargins / 2 }px)` }
           ml={ 3 }
         />
-      ) : <span>-</span> }
+      ) }
     </Flex>
   );
 };

ui/shared/address/utils.ts

+import type { AddressParam } from 'types/api/addressParams';
+
 export type TxCourseType = 'in' | 'out' | 'self' | 'unspecified';
 
 export function getTxCourseType(from: string, to: string | undefined, current?: string): TxCourseType {
@@ -19,3 +21,14 @@ export function getTxCourseType(from: string, to: string | undefined, current?:
 
   return 'unspecified';
 }
+
+export const unknownAddress: Omit<AddressParam, 'hash'> = {
+  is_contract: false,
+  is_verified: false,
+  implementation_name: '',
+  name: '',
+  private_tags: [],
+  public_tags: [],
+  watchlist_names: [],
+  ens_domain_name: null,
+};

ui/shared/pagination/utils.ts

+import type { PaginationParams } from './types';
+
+export const emptyPagination: PaginationParams = {
+  page: 1,
+  onNextPageClick: () => {},
+  onPrevPageClick: () => {},
+  resetPage: () => {},
+  hasPages: false,
+  hasNextPage: false,
+  canGoBackwards: false,
+  isLoading: false,
+  isVisible: false,
+};

ui/shared/statusTag/TxStatus.tsx

@@ -12,6 +12,10 @@ export interface Props {
 }
 
 const TxStatus = ({ status, errorText, isLoading }: Props) => {
+  if (status === undefined) {
+    return null;
+  }
+
   let text;
   let type: StatusTagType;
 

ui/tx/TxDetailsDegraded.tsx

@@ -37,6 +37,7 @@ const TxDetailsDegraded = ({ hash, txQuery }: Props) => {
     queryKey: [ 'RPC', 'tx', { hash } ],
     queryFn: async() => {
       const tx = await publicClient.getTransaction({ hash: hash as `0x${ string }` });
+
       if (!tx) {
         throw new Error('Not found');
       }

ui/txs/TxsContent.tsx

-import { Box, Show, Hide } from '@chakra-ui/react';
+import { Show, Hide } from '@chakra-ui/react';
 import React from 'react';
 
 import type { AddressFromToFilter } from 'types/api/address';
@@ -8,11 +8,10 @@ import useIsMobile from 'lib/hooks/useIsMobile';
 import AddressCsvExportLink from 'ui/address/AddressCsvExportLink';
 import DataListDisplay from 'ui/shared/DataListDisplay';
 import type { QueryWithPagesResult } from 'ui/shared/pagination/useQueryWithPages';
-import * as SocketNewItemsNotice from 'ui/shared/SocketNewItemsNotice';
 import getNextSortValue from 'ui/shared/sort/getNextSortValue';
 
 import TxsHeaderMobile from './TxsHeaderMobile';
-import TxsListItem from './TxsListItem';
+import TxsList from './TxsList';
 import TxsTable from './TxsTable';
 
 const SORT_SEQUENCE: Record<TransactionsSortingField, Array<TransactionsSortingValue | undefined>> = {
@@ -66,26 +65,16 @@ const TxsContent = ({
   const content = items ? (
     <>
       <Show below="lg" ssr={ false }>
-        <Box>
-          { showSocketInfo && (
-            <SocketNewItemsNotice.Mobile
-              url={ window.location.href }
-              num={ socketInfoNum }
-              alert={ socketInfoAlert }
-              isLoading={ isPlaceholderData }
-            />
-          ) }
-          { items.map((tx, index) => (
-            <TxsListItem
-              key={ tx.hash + (isPlaceholderData ? index : '') }
-              tx={ tx }
-              showBlockInfo={ showBlockInfo }
-              currentAddress={ currentAddress }
-              enableTimeIncrement={ enableTimeIncrement }
-              isLoading={ isPlaceholderData }
-            />
-          )) }
-        </Box>
+        <TxsList
+          showBlockInfo={ showBlockInfo }
+          showSocketInfo={ showSocketInfo }
+          socketInfoAlert={ socketInfoAlert }
+          socketInfoNum={ socketInfoNum }
+          isLoading={ isPlaceholderData }
+          enableTimeIncrement={ enableTimeIncrement }
+          currentAddress={ currentAddress }
+          items={ items }
+        />
       </Show>
       <Hide below="lg" ssr={ false }>
         <TxsTable

ui/txs/TxsList.tsx

+import { Box } from '@chakra-ui/react';
+import React from 'react';
+
+import type { Transaction } from 'types/api/transaction';
+
+import useLazyRenderedList from 'lib/hooks/useLazyRenderedList';
+import * as SocketNewItemsNotice from 'ui/shared/SocketNewItemsNotice';
+
+import TxsListItem from './TxsListItem';
+
+interface Props {
+  showBlockInfo: boolean;
+  showSocketInfo?: boolean;
+  socketInfoAlert?: string;
+  socketInfoNum?: number;
+  enableTimeIncrement?: boolean;
+  currentAddress?: string;
+  isLoading: boolean;
+  items: Array<Transaction>;
+}
+
+const TxsList = (props: Props) => {
+  const { cutRef, renderedItemsNum } = useLazyRenderedList(props.items, !props.isLoading);
+
+  return (
+    <Box>
+      { props.showSocketInfo && (
+        <SocketNewItemsNotice.Mobile
+          url={ window.location.href }
+          num={ props.socketInfoNum }
+          alert={ props.socketInfoAlert }
+          isLoading={ props.isLoading }
+        />
+      ) }
+      { props.items.slice(0, renderedItemsNum).map((tx, index) => (
+        <TxsListItem
+          key={ tx.hash + (props.isLoading ? index : '') }
+          tx={ tx }
+          showBlockInfo={ props.showBlockInfo }
+          currentAddress={ props.currentAddress }
+          enableTimeIncrement={ props.enableTimeIncrement }
+          isLoading={ props.isLoading }
+        />
+      )) }
+      <Box ref={ cutRef } h={ 0 }/>
+    </Box>
+  );
+};
+
+export default React.memo(TxsList);

ui/txs/TxsTable.tsx

@@ -6,6 +6,7 @@ import type { Transaction, TransactionsSortingField, TransactionsSortingValue }
 
 import config from 'configs/app';
 import { AddressHighlightProvider } from 'lib/contexts/addressHighlight';
+import useLazyRenderedList from 'lib/hooks/useLazyRenderedList';
 import { currencyUnits } from 'lib/units';
 import IconSvg from 'ui/shared/IconSvg';
 import * as SocketNewItemsNotice from 'ui/shared/SocketNewItemsNotice';
@@ -40,6 +41,8 @@ const TxsTable = ({
   enableTimeIncrement,
   isLoading,
 }: Props) => {
+  const { cutRef, renderedItemsNum } = useLazyRenderedList(txs, !isLoading);
+
   return (
     <AddressHighlightProvider>
       <Table variant="simple" minWidth="950px" size="xs">
@@ -81,7 +84,7 @@ const TxsTable = ({
             />
           ) }
           <AnimatePresence initial={ false }>
-            { txs.map((item, index) => (
+            { txs.slice(0, renderedItemsNum).map((item, index) => (
               <TxsTableItem
                 key={ item.hash + (isLoading ? index : '') }
                 tx={ item }
@@ -94,6 +97,7 @@ const TxsTable = ({
           </AnimatePresence>
         </Tbody>
       </Table>
+      <div ref={ cutRef }/>
     </AddressHighlightProvider>
   );
 };

ui/withdrawals/WithdrawalsList.tsx

+import { Box } from '@chakra-ui/react';
+import React from 'react';
+
+import type { AddressWithdrawalsItem } from 'types/api/address';
+import type { BlockWithdrawalsItem } from 'types/api/block';
+import type { WithdrawalsItem } from 'types/api/withdrawals';
+
+import useLazyRenderedList from 'lib/hooks/useLazyRenderedList';
+
+import WithdrawalsListItem from './WithdrawalsListItem';
+
+type Props = {
+  isLoading?: boolean;
+} & ({
+  items: Array<WithdrawalsItem>;
+  view: 'list';
+} | {
+  items: Array<AddressWithdrawalsItem>;
+  view: 'address';
+} | {
+  items: Array<BlockWithdrawalsItem>;
+  view: 'block';
+});
+
+const WithdrawalsList = ({ items, view, isLoading }: Props) => {
+  const { cutRef, renderedItemsNum } = useLazyRenderedList(items, !isLoading);
+
+  return (
+    <Box>
+      { items.slice(0, renderedItemsNum).map((item, index) => {
+
+        const key = item.index + (isLoading ? String(index) : '');
+
+        switch (view) {
+          case 'address': {
+            return (
+              <WithdrawalsListItem
+                key={ key }
+                item={ item as AddressWithdrawalsItem }
+                view={ view }
+                isLoading={ isLoading }
+              />
+            );
+          }
+          case 'block': {
+            return (
+              <WithdrawalsListItem
+                key={ key }
+                item={ item as BlockWithdrawalsItem }
+                view={ view }
+                isLoading={ isLoading }
+              />
+            );
+          }
+          case 'list': {
+            return (
+              <WithdrawalsListItem
+                key={ key }
+                item={ item as WithdrawalsItem }
+                view={ view }
+                isLoading={ isLoading }
+              />
+            );
+          }
+        }
+      }) }
+      <div ref={ cutRef }/>
+    </Box>
+  );
+};
+
+export default React.memo(WithdrawalsList);

ui/withdrawals/WithdrawalsTable.tsx

@@ -6,6 +6,7 @@ import type { BlockWithdrawalsItem } from 'types/api/block';
 import type { WithdrawalsItem } from 'types/api/withdrawals';
 
 import config from 'configs/app';
+import useLazyRenderedList from 'lib/hooks/useLazyRenderedList';
 import { default as Thead } from 'ui/shared/TheadSticky';
 
 import WithdrawalsTableItem from './WithdrawalsTableItem';
@@ -26,7 +27,9 @@ const feature = config.features.beaconChain;
    view: 'block';
  });
 
-const WithdrawalsTable = ({ items, isLoading, top, view = 'list' }: Props) => {
+const WithdrawalsTable = ({ items, isLoading, top, view }: Props) => {
+  const { cutRef, renderedItemsNum } = useLazyRenderedList(items, !isLoading);
+
   if (!feature.isEnabled) {
     return null;
   }
@@ -44,15 +47,16 @@ const WithdrawalsTable = ({ items, isLoading, top, view = 'list' }: Props) => {
         </Tr>
       </Thead>
       <Tbody>
-        { view === 'list' && (items as Array<WithdrawalsItem>).map((item, index) => (
+        { view === 'list' && (items as Array<WithdrawalsItem>).slice(0, renderedItemsNum).map((item, index) => (
           <WithdrawalsTableItem key={ item.index + (isLoading ? String(index) : '') } item={ item } view="list" isLoading={ isLoading }/>
         )) }
-        { view === 'address' && (items as Array<AddressWithdrawalsItem>).map((item, index) => (
+        { view === 'address' && (items as Array<AddressWithdrawalsItem>).slice(0, renderedItemsNum).map((item, index) => (
           <WithdrawalsTableItem key={ item.index + (isLoading ? String(index) : '') } item={ item } view="address" isLoading={ isLoading }/>
         )) }
-        { view === 'block' && (items as Array<BlockWithdrawalsItem>).map((item, index) => (
+        { view === 'block' && (items as Array<BlockWithdrawalsItem>).slice(0, renderedItemsNum).map((item, index) => (
           <WithdrawalsTableItem key={ item.index + (isLoading ? String(index) : '') } item={ item } view="block" isLoading={ isLoading }/>
         )) }
+        <tr ref={ cutRef }/>
       </Tbody>
     </Table>
   );

ui/withdrawals/WithdrawalsTableItem.tsx

@@ -10,16 +10,16 @@ import CurrencyValue from 'ui/shared/CurrencyValue';
 import AddressEntity from 'ui/shared/entities/address/AddressEntity';
 import BlockEntity from 'ui/shared/entities/block/BlockEntity';
 
- type Props = ({
-   item: WithdrawalsItem;
-   view: 'list';
- } | {
-   item: AddressWithdrawalsItem;
-   view: 'address';
- } | {
-   item: BlockWithdrawalsItem;
-   view: 'block';
- }) & { isLoading?: boolean };
+type Props = ({
+  item: WithdrawalsItem;
+  view: 'list';
+} | {
+  item: AddressWithdrawalsItem;
+  view: 'address';
+} | {
+  item: BlockWithdrawalsItem;
+  view: 'block';
+}) & { isLoading?: boolean };
 
 const WithdrawalsTableItem = ({ item, view, isLoading }: Props) => {
   return (