Merge pull request #1257 from input-output-hk/feat/nft-metadata-parsi…

…ng-loose-mode

feat(core): nft metadata parsing loose mode

packages/core/src/Asset/NftMetadata/fromMetadatum.ts

@@ -10,6 +10,7 @@ import { isNotNil } from '@cardano-sdk/util';
 import difference from 'lodash/difference';
 
 const isString = (obj: unknown): obj is string => typeof obj === 'string';
+const VersionRegExp = /^\d+\.?\d?$/;
 
 const metadatumToString = (metadatum: Cardano.Metadatum | undefined): string | undefined => {
   if (Array.isArray(metadatum)) {
@@ -96,39 +97,57 @@ const getAssetMetadata = (policy: Cardano.MetadatumMap, assetName: Cardano.Asset
       })()
   );
 
+type AssetIdParts = Pick<AssetInfo, 'policyId' | 'name'>;
+const getName = (assetMetadata: Cardano.MetadatumMap, version: string, asset: AssetIdParts, logger: Logger) => {
+  const name = asString(assetMetadata.get('name'));
+  if (name) return name;
+  if (version === '1.0') {
+    try {
+      return AssetName.toUTF8(asset.name);
+    } catch (error) {
+      logger.warn(error);
+    }
+  }
+};
+
+const parseVersion = (version: Cardano.Metadatum | undefined) => {
+  if (!version) return '1.0';
+  if (typeof version === 'bigint') {
+    return `${version}.0`;
+  }
+  const stringVersion = asString(version);
+  if (stringVersion && VersionRegExp.test(stringVersion)) {
+    return `${Number(stringVersion)}.0`;
+  }
+};
+
 /**
  * @param asset try to parse NftMetadata for this asset
  * @param metadata transaction metadata (see CIP-0025)
  * @param logger logger to use
  */
 // eslint-disable-next-line complexity
 export const fromMetadatum = (
-  asset: Pick<AssetInfo, 'policyId' | 'name'>,
+  asset: AssetIdParts,
   metadata: Cardano.TxMetadata | undefined,
-  logger: Logger
+  logger: Logger,
+  strict = false
 ): NftMetadata | null => {
   const cip25Metadata = metadata?.get(721n);
   if (!cip25Metadata) return null;
   const cip25MetadatumMap = asMetadatumMap(cip25Metadata);
   if (!cip25MetadatumMap) return null;
   const policy = getPolicyMetadata(cip25MetadatumMap, asset.policyId);
   if (!policy) return null;
+  const version = parseVersion(policy.get('version'));
+  if (!version) return null;
   const assetMetadata = getAssetMetadata(policy, asset.name);
   if (!assetMetadata) return null;
-  const version = asString(policy.get('version')) || '1.0';
-  let name = asString(assetMetadata.get('name'));
+  const name = getName(assetMetadata, version, asset, logger);
   const image = metadatumToString(assetMetadata.get('image'));
   const assetId = Cardano.AssetId.fromParts(asset.policyId, asset.name);
 
-  if (version === '1.0' && !name) {
-    try {
-      name = AssetName.toUTF8(asset.name);
-    } catch (error) {
-      logger.warn(error);
-    }
-  }
-
-  if (!name || !image) {
+  if ((strict && !name) || !image) {
     logger.warn(missingFieldLogMessage(!name ? 'name' : 'image', assetId, true));
     return null;
   }
@@ -142,7 +161,7 @@ export const fromMetadatum = (
       files: files?.map((file) => mapFile(file, assetId, logger)).filter(isNotNil),
       image: Uri(image),
       mediaType: mediaType ? ImageMediaType(mediaType) : undefined,
-      name,
+      name: name || '',
       otherProperties: mapOtherProperties(assetMetadata, ['name', 'image', 'mediaType', 'description', 'files']),
       version
     };

packages/core/src/Asset/NftMetadata/fromPlutusData.ts

@@ -83,17 +83,45 @@ const mapFiles = (files: string | Cardano.PlutusData | undefined, logger: Logger
   return files.items.map((file) => mapFile(file, logger)).filter(isNotNil);
 };
 
+const getConditionalValidators = (strict: boolean, logger: Logger) => ({
+  isNameValid: (name: Cardano.PlutusData | string | undefined): name is string | undefined => {
+    if (typeof name === 'string') return true;
+    if (typeof name === 'undefined') {
+      if (strict) {
+        logger.debug('Invalid PlutusData: "name" is required');
+        return false;
+      }
+      return true;
+    }
+    logger.debug('Invalid PlutusData: "name" must be utf8 bounded bytes');
+    return false;
+  },
+  isValidDatumShape: (plutusData: Cardano.PlutusData | undefined): plutusData is Cardano.ConstrPlutusData => {
+    const minNumberOfFields = strict ? 3 : 2;
+    const isValid =
+      isConstrPlutusData(plutusData) &&
+      plutusData.constructor === 0n &&
+      plutusData.fields.items.length >= minNumberOfFields;
+    if (!isValid)
+      logger.debug(
+        `Invalid PlutusData: expecting ConstrPlutusData with 0th constructor and ${minNumberOfFields} items`
+      );
+    return isValid;
+  }
+});
+
 /**
  * @param plutusData CIP-0068 (label 222) datum
  * @param parentLogger logger
  */
 export const fromPlutusData = (
   plutusData: Cardano.PlutusData | undefined,
-  parentLogger: Logger
+  parentLogger: Logger,
+  strict = false
 ): NftMetadata | null => {
   const logger = contextLogger(parentLogger, 'NftMetadata.fromPlutusData');
-  if (!isConstrPlutusData(plutusData) || plutusData.constructor !== 0n || plutusData.fields.items.length < 3) {
-    logger.debug('Invalid PlutusData: expecting ConstrPlutusData with 0th constructor and 3 items');
+  const conditionalValidators = getConditionalValidators(strict, logger);
+  if (!conditionalValidators.isValidDatumShape(plutusData)) {
     return null;
   }
 
@@ -106,8 +134,12 @@ export const fromPlutusData = (
   const nftMetadataRecord = tryConvertPlutusMapToUtf8Record(nftMetadata, logger);
   const { name, image, mediaType, description, files, ...additionalProperties } = nftMetadataRecord;
 
-  if (typeof name !== 'string' || typeof image !== 'string') {
-    logger.debug('Invalid PlutusData: missing required field (name, image)');
+  if (!conditionalValidators.isNameValid(name)) {
+    return null;
+  }
+
+  if (typeof image !== 'string') {
+    logger.debug('Invalid PlutusData: "image" must be UTF-8 bounded bytes');
     return null;
   }
 
@@ -121,7 +153,7 @@ export const fromPlutusData = (
     files: mapFiles(files, logger),
     image: imageAsUri,
     mediaType: tryCoerce(mediaType, ImageMediaType, logger),
-    name,
+    name: name || '',
     otherProperties: undefinedIfEmpty(mapOtherProperties(additionalProperties, logger)),
     version: version.toString()
   };