feat: update blobs endpoint to use versioned_hashes instead of indices as filter (#8264)

**Motivation**

Latest updates from ethereum/beacon-APIs#546

**Description**

Update `getBlobs` beacon api to use `versioned_hashes` instead of
`indices` as filter

Author: nflaig

packages/api/src/beacon/routes/beacon/block.ts

@@ -235,12 +235,12 @@ export type Endpoints = {
     "GET",
     BlockArgs & {
       /**
-       * Array of indices for blobs to request for in the specified block.
+       * Array of versioned hashes for blobs to request for in the specified block.
        * Returns all blobs in the block if not specified.
        */
-      indices?: number[];
+      versionedHashes?: string[];
     },
-    {params: {block_id: string}; query: {indices?: number[]}},
+    {params: {block_id: string}; query: {versioned_hashes?: string[]}},
     deneb.Blobs,
     ExecutionOptimisticAndFinalizedMeta
   >;
@@ -583,9 +583,15 @@ export function getDefinitions(config: ChainForkConfig): RouteDefinitions<Endpoi
       url: "/eth/v1/beacon/blobs/{block_id}",
       method: "GET",
       req: {
-        writeReq: ({blockId, indices}) => ({params: {block_id: blockId.toString()}, query: {indices}}),
-        parseReq: ({params, query}) => ({blockId: params.block_id, indices: query.indices}),
-        schema: {params: {block_id: Schema.StringRequired}, query: {indices: Schema.UintArray}},
+        writeReq: ({blockId, versionedHashes}) => ({
+          params: {block_id: blockId.toString()},
+          query: {versioned_hashes: versionedHashes},
+        }),
+        parseReq: ({params, query}) => ({
+          blockId: params.block_id,
+          versionedHashes: query.versioned_hashes?.map((hash) => hash.toLowerCase()),
+        }),
+        schema: {params: {block_id: Schema.StringRequired}, query: {versioned_hashes: Schema.StringArray}},
       },
       resp: {
         data: ssz.deneb.Blobs,

packages/api/test/unit/beacon/oapiSpec.test.ts

@@ -20,7 +20,7 @@ import {testData as validatorTestData} from "./testData/validator.js";
 // Solutions: https://stackoverflow.com/questions/46745014/alternative-for-dirname-in-node-js-when-using-es6-modules
 const __dirname = path.dirname(fileURLToPath(import.meta.url));
 
-const version = "v4.0.0-alpha.0";
+const version = "v4.0.0-alpha.1";
 const openApiFile: OpenApiFile = {
   url: `https://github.com/ethereum/beacon-APIs/releases/download/${version}/beacon-node-oapi.json`,
   filepath: path.join(__dirname, "../../../oapi-schemas/beacon-node-oapi.json"),
@@ -68,7 +68,10 @@ const ignoredProperties: Record<string, IgnoredProperty> = {
 const openApiJson = await fetchOpenApiSpec(openApiFile);
 runTestCheckAgainstSpec(openApiJson, definitions, testDatas, ignoredOperations, ignoredProperties);
 
-const ignoredTopics: string[] = [];
+const ignoredTopics: string[] = [
+  // TODO: fix in follow-up PR
+  "payload_attributes",
+];
 
 // eventstream types are defined as comments in the description of "examples".
 // The function runTestCheckAgainstSpec() can't handle those, so the custom code before:

packages/api/test/unit/beacon/testData/beacon.ts

@@ -1,6 +1,6 @@
-import {toHexString} from "@chainsafe/ssz";
 import {ForkName} from "@lodestar/params";
 import {ssz} from "@lodestar/types";
+import {toHex} from "@lodestar/utils";
 import {
   BlockHeaderResponse,
   BroadcastValidation,
@@ -13,7 +13,8 @@ const root = new Uint8Array(32).fill(1);
 const randao = new Uint8Array(32).fill(1);
 const balance = 32e9;
 const reward = 32e9;
-const pubkeyHex = toHexString(Buffer.alloc(48, 1));
+const pubkeyHex = toHex(Buffer.alloc(48, 1));
+const versionedHash = ssz.deneb.VersionedHash.defaultValue();
 
 const blockHeaderResponse: BlockHeaderResponse = {
   root,
@@ -61,7 +62,7 @@ export const testData: GenericServerTestCases<Endpoints> = {
     res: {data: blockHeaderResponse, meta: {executionOptimistic: true, finalized: false}},
   },
   getBlockHeaders: {
-    args: {slot: 1, parentRoot: toHexString(root)},
+    args: {slot: 1, parentRoot: toHex(root)},
     res: {data: [blockHeaderResponse], meta: {executionOptimistic: true, finalized: false}},
   },
   getBlockRoot: {
@@ -98,7 +99,7 @@ export const testData: GenericServerTestCases<Endpoints> = {
     },
   },
   getBlobs: {
-    args: {blockId: "head", indices: [0]},
+    args: {blockId: "head", versionedHashes: [toHex(versionedHash)]},
     res: {
       data: [ssz.deneb.Blob.defaultValue()],
       meta: {executionOptimistic: true, finalized: false},

packages/beacon-node/src/api/impl/beacon/blocks/index.ts

@@ -634,8 +634,8 @@ export function getBeaconBlockApi({
       };
     },
 
-    async getBlobs({blockId, indices}) {
-      assertUniqueItems(indices, "Duplicate indices provided");
+    async getBlobs({blockId, versionedHashes}) {
+      assertUniqueItems(versionedHashes, "Duplicate versioned hashes provided");
 
       const {block, executionOptimistic, finalized} = await getBlockResponse(chain, blockId);
       const fork = config.getForkName(block.message.slot);
@@ -682,8 +682,27 @@ export function getBeaconBlockApi({
         blobs = [];
       }
 
+      if (blobs.length && versionedHashes?.length) {
+        const kzgCommitments = (block as deneb.SignedBeaconBlock).message.body.blobKzgCommitments;
+
+        const blockVersionedHashes = kzgCommitments.map((commitment) =>
+          toHex(kzgCommitmentToVersionedHash(commitment))
+        );
+
+        const requestedIndices: number[] = [];
+        for (const requestedHash of versionedHashes) {
+          const index = blockVersionedHashes.findIndex((hash) => hash === requestedHash);
+          if (index === -1) {
+            throw new ApiError(400, `Versioned hash ${requestedHash} not found in block`);
+          }
+          requestedIndices.push(index);
+        }
+
+        blobs = requestedIndices.sort((a, b) => a - b).map((index) => blobs[index]);
+      }
+
       return {
-        data: indices ? blobs.filter((_, i) => indices.includes(i)) : blobs,
+        data: blobs,
         meta: {
           executionOptimistic,
           finalized,