Add SSZ encoding support to REST API endpoint /eth/v1/validator/register_validator (#6943)

* Add SSZ version of /eth/v1/validator/register_validator

* Add ability to test `application/octet-stream` bodies to `restclient`.
Add tests for SSZ version `/eth/v1/validator/register_validator`.

* Fix test value to be correct hexadecimal string.

* Update copyright years.

Author: cheatfate

beacon_chain/rpc/rest_constants.nim

@@ -1,5 +1,5 @@
 # beacon_chain
-# Copyright (c) 2021-2024 Status Research & Development GmbH
+# Copyright (c) 2021-2025 Status Research & Development GmbH
 # Licensed and distributed under either of
 #   * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
 #   * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
@@ -271,3 +271,4 @@ const
     "Unable to load state for parent block, database corrupt?"
   RewardOverflowError* =
     "Reward value overflow"
+  InvalidContentTypeError* = "Invalid content type"

beacon_chain/rpc/rest_validator_api.nim

@@ -1,4 +1,4 @@
-# Copyright (c) 2018-2024 Status Research & Development GmbH
+# Copyright (c) 2018-2025 Status Research & Development GmbH
 # Licensed and distributed under either of
 #   * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
 #   * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
@@ -1215,25 +1215,21 @@ proc installValidatorApiHandlers*(router: var RestRouter, node: BeaconNode) =
   router.api2(MethodPost,
               "/eth/v1/validator/register_validator") do (
     contentBody: Option[ContentBody]) -> RestApiResponse:
+    if contentBody.isNone():
+      return RestApiResponse.jsonError(Http400, EmptyRequestBodyError)
     let
-      body =
-        block:
-          if contentBody.isNone():
-            return RestApiResponse.jsonError(Http400, EmptyRequestBodyError)
-          let dres = decodeBody(seq[SignedValidatorRegistrationV1], contentBody.get())
-          if dres.isErr():
-            return RestApiResponse.jsonError(Http400,
-                                             InvalidPrepareBeaconProposerError)
-          dres.get()
+      body = decodeBodyJsonOrSsz(seq[SignedValidatorRegistrationV1],
+                                 contentBody.get()).valueOr:
+        return RestApiResponse.jsonError(error)
 
-    for signedValidatorRegistration in body:
+    for registration in body:
       # Don't validate beyond syntactically, because
       # "requests containing currently inactive or unknown validator pubkeys
       # will be accepted, as they may become active at a later epoch". Along
       # these lines, even if it's adding a validator the BN already has as a
       # local validator, the keymanager API might remove that from the BN.
-      node.externalBuilderRegistrations[signedValidatorRegistration.message.pubkey] =
-        signedValidatorRegistration
+      node.externalBuilderRegistrations[registration.message.pubkey] =
+        registration
 
     RestApiResponse.response(Http200)
 

beacon_chain/spec/eth2_apis/eth2_rest_serialization.nim

@@ -3036,7 +3036,7 @@ proc decodeBody*(
                                            [version, $exc.msg]))
       ok(RestPublishedSignedBeaconBlock(ForkedSignedBeaconBlock.init(blck)))
   else:
-    err(RestErrorMessage.init(Http415, "Invalid content type",
+    err(RestErrorMessage.init(Http415, InvalidContentTypeError,
                               [version, $body.contentType]))
 
 proc decodeBody*(
@@ -3232,9 +3232,45 @@ proc decodeBody*(
       ok(RestPublishedSignedBlockContents(
         kind: ConsensusFork.Fulu, fuluData: blckContents))
   else:
-    err(RestErrorMessage.init(Http415, "Invalid content type",
+    err(RestErrorMessage.init(Http415, InvalidContentTypeError,
                               [version, $body.contentType]))
 
+proc decodeBodyJsonOrSsz*(
+    t: typedesc[seq[SignedValidatorRegistrationV1]],
+    body: ContentBody
+): Result[seq[SignedValidatorRegistrationV1], RestErrorMessage] =
+  if body.contentType == ApplicationJsonMediaType:
+    let data =
+      try:
+        RestJson.decode(
+          body.data,
+          seq[SignedValidatorRegistrationV1],
+          requireAllFields = true,
+          allowUnknownFields = true)
+      except SerializationError as exc:
+        debug "Failed to deserialize REST JSON data",
+              err = exc.formatMsg("<data>")
+        return err(
+          RestErrorMessage.init(Http400, UnableDecodeError,
+                                [exc.formatMsg("<data>")]))
+    ok(data)
+  elif body.contentType == OctetStreamMediaType:
+    let data =
+      try:
+        SSZ.decode(
+          body.data,
+          List[SignedValidatorRegistrationV1, Limit VALIDATOR_REGISTRY_LIMIT])
+      except SerializationError as exc:
+        debug "Failed to deserialize REST SSZ data",
+              err = exc.formatMsg("<data>")
+        return err(
+          RestErrorMessage.init(Http400, UnableDecodeError,
+                                [exc.formatMsg("<data>")]))
+    ok(data.toSeq)
+  else:
+    err(RestErrorMessage.init(Http415, InvalidContentTypeError,
+                              [$body.contentType]))
+
 proc decodeBody*[T](t: typedesc[T],
                     body: ContentBody): Result[T, cstring] =
   if body.contentType != ApplicationJsonMediaType:
@@ -3285,7 +3321,7 @@ proc decodeBodyJsonOrSsz*[T](t: typedesc[T],
             RestErrorMessage.init(Http400, UnexpectedDecodeError, [$exc.msg]))
     ok(blck)
   else:
-    err(RestErrorMessage.init(Http415, "Invalid content type",
+    err(RestErrorMessage.init(Http415, InvalidContentTypeError,
                               [$body.contentType]))
 
 proc encodeBytes*[T: EncodeTypes](value: T,

ncli/resttest-rules.json

@@ -5000,6 +5000,31 @@
       "headers": [{"key": "Content-Type", "value": "application/json", "operator": "equals"}]
     }
   },
+  {
+    "topics": ["validator", "register_validators"],
+    "request": {
+      "url": "/eth/v1/validator/register_validator",
+      "method": "POST",
+      "headers": {"Accept": "application/json"},
+      "body": {"content-type": "application/octet-stream", "data": "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"}
+    },
+    "response": {
+      "status": {"operator": "equals", "value": "200"}
+    }
+  },
+  {
+    "topics": ["validator", "register_validators"],
+    "request": {
+      "url": "/eth/v1/validator/register_validator",
+      "method": "POST",
+      "headers": {"Accept": "application/json"},
+      "body": {"content-type": "application/octet-stream", "data": "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"}
+    },
+    "response": {
+      "status": {"operator": "equals", "value": "400"},
+      "headers": [{"key": "Content-Type", "value": "application/json", "operator": "equals"}]
+    }
+  },
   {
       "topics": ["key_management", "list_keys"],
       "request": {

ncli/resttest.nim

@@ -1,5 +1,5 @@
 # beacon_chain
-# Copyright (c) 2021-2024 Status Research & Development GmbH
+# Copyright (c) 2021-2025 Status Research & Development GmbH
 # Licensed and distributed under either of
 #   * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
 #   * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
@@ -10,7 +10,7 @@
 import
   std/[strutils, os, options, uri, json, tables],
   results,
-  stew/[io2, base10],
+  stew/[io2, base10, byteutils],
   confutils, chronicles, httputils,
   chronos, chronos/streams/[asyncstream, tlsstream]
 
@@ -455,7 +455,15 @@ proc prepareRequest(uri: Uri,
           return err("Field `body.data` must be present")
         if bdata.kind != JString:
           return err("Field `body.data` should be string")
-        (btype.str, bdata.str)
+        if toLowerAscii(btype.str) == "application/octet-stream":
+          let data =
+            try:
+              string.fromBytes(hexToSeqByte(bdata.str))
+            except ValueError:
+              return err("Field `body.data` should be valid hexadecimal string")
+          (btype.str, data)
+        else:
+          (btype.str, bdata.str)
 
   var res = meth & " " & uri.path & requestUri & " HTTP/1.1\r\n"
   res.add("Content-Length: " & Base10.toString(uint64(len(requestBodyData))) &