feat(graphql): standardize error handling across resolvers with null returns

Implemented consistent error handling across multiple GraphQL resolvers:
- Updated AllowlistRecordResolver, AttestationResolver, AttestationSchemaResolver, ContractResolver, and FractionResolver
- Replaced error throwing with null returns for failed resolver queries
- Added detailed console error logging for debugging
- Updated corresponding test cases to expect null instead of thrown errors
- Improved resilience of GraphQL endpoint by preventing query failures

Author: bitbeckers

src/services/graphql/resolvers/allowlistRecordResolver.ts

@@ -59,7 +59,14 @@ class AllowlistRecordResolver {
    */
   @Query(() => GetAllowlistRecordResponse)
   async allowlistRecords(@Args() args: GetAllowlistRecordsArgs) {
-    return await this.allowlistRecordService.getAllowlistRecords(args);
+    try {
+      return await this.allowlistRecordService.getAllowlistRecords(args);
+    } catch (e) {
+      console.error(
+        `[AllowlistRecordResolver::allowlistRecords] Error fetching allowlist records: ${(e as Error).message}`,
+      );
+      return null;
+    }
   }
 
   /**
@@ -87,9 +94,16 @@ class AllowlistRecordResolver {
    */
   @FieldResolver()
   async hypercert(@Root() allowlistRecord: AllowlistRecord) {
-    return await this.hypercertsService.getHypercert({
-      where: { hypercert_id: { eq: allowlistRecord.hypercert_id } },
-    });
+    try {
+      return await this.hypercertsService.getHypercert({
+        where: { hypercert_id: { eq: allowlistRecord.hypercert_id } },
+      });
+    } catch (e) {
+      console.error(
+        `[AllowlistRecordResolver::hypercert] Error fetching hypercert: ${(e as Error).message}`,
+      );
+      return null;
+    }
   }
 }
 

src/services/graphql/resolvers/attestationResolver.ts

@@ -2,15 +2,15 @@ import { inject, injectable } from "tsyringe";
 import { Args, FieldResolver, Query, Resolver, Root } from "type-graphql";
 import { getAddress, isAddress } from "viem";
 import { z } from "zod";
-import { AttestationService } from "../../database/entities/AttestationEntityService.js";
-import { AttestationSchemaService } from "../../database/entities/AttestationSchemaEntityService.js";
-import { HypercertsService } from "../../database/entities/HypercertsEntityService.js";
-import { MetadataService } from "../../database/entities/MetadataEntityService.js";
 import { GetAttestationsArgs } from "../../../graphql/schemas/args/attestationArgs.js";
 import {
   Attestation,
   GetAttestationsResponse,
 } from "../../../graphql/schemas/typeDefs/attestationTypeDefs.js";
+import { AttestationService } from "../../database/entities/AttestationEntityService.js";
+import { AttestationSchemaService } from "../../database/entities/AttestationSchemaEntityService.js";
+import { HypercertsService } from "../../database/entities/HypercertsEntityService.js";
+import { MetadataService } from "../../database/entities/MetadataEntityService.js";
 
 /**
  * Schema for validating hypercert pointer data in attestations.
@@ -70,9 +70,9 @@ const HypercertPointer = z.object({
  * - Field resolution for metadata associated with the attested hypercert
  *
  * Error handling:
- * - Invalid attestation data returns undefined for related fields
+ * - Invalid attestation data returns null for related fields
  * - Database errors are propagated to the GraphQL layer
- * - Schema validation errors result in undefined hypercert IDs
+ * - Schema validation errors result in null hypercert IDs
  *
  * @injectable Marks the class as injectable for dependency injection with tsyringe
  * @resolver Marks the class as a GraphQL resolver for the Attestation type
@@ -107,7 +107,6 @@ class AttestationResolver {
    * @returns A promise that resolves to an object containing:
    *          - data: Array of attestations matching the query
    *          - count: Total number of matching attestations
-   * @throws {Error} If the database query fails
    *
    * Filtering supports:
    * - Attestation fields (id, supported_schemas_id, etc.)
@@ -137,7 +136,14 @@ class AttestationResolver {
    */
   @Query(() => GetAttestationsResponse)
   async attestations(@Args() args: GetAttestationsArgs) {
-    return await this.attestationService.getAttestations(args);
+    try {
+      return await this.attestationService.getAttestations(args);
+    } catch (e) {
+      console.error(
+        `[AttestationResolver::attestations] Error fetching attestations: ${(e as Error).message}`,
+      );
+      return null;
+    }
   }
 
   /**
@@ -152,7 +158,6 @@ class AttestationResolver {
    *            - attestation.data is null/undefined
    *            - hypercert ID cannot be extracted from data
    *            - no matching hypercert is found
-   * @throws {Error} If the hypercert service query fails
    *
    * @example
    * Query with hypercert field:
@@ -173,19 +178,26 @@ class AttestationResolver {
    */
   @FieldResolver()
   async hypercert(@Root() attestation: Attestation) {
-    if (!attestation.data) return;
+    try {
+      if (!attestation.data) return null;
 
-    const attested_hypercert_id = this.getHypercertIdFromAttestationData(
-      attestation.data,
-    );
+      const attested_hypercert_id = this.getHypercertIdFromAttestationData(
+        attestation.data,
+      );
 
-    if (!attested_hypercert_id) return;
+      if (!attested_hypercert_id) return null;
 
-    return await this.hypercertService.getHypercert({
-      where: {
-        hypercert_id: { eq: attested_hypercert_id },
-      },
-    });
+      return await this.hypercertService.getHypercert({
+        where: {
+          hypercert_id: { eq: attested_hypercert_id },
+        },
+      });
+    } catch (e) {
+      console.error(
+        `[AttestationResolver::hypercert] Error fetching hypercert: ${(e as Error).message}`,
+      );
+      return null;
+    }
   }
 
   /**
@@ -196,7 +208,6 @@ class AttestationResolver {
    * @returns A promise that resolves to:
    *          - The associated schema data if found
    *          - undefined if no schema ID is present
-   * @throws {Error} If the schema service query fails
    *
    * @example
    * Query with schema field:
@@ -219,13 +230,20 @@ class AttestationResolver {
    */
   @FieldResolver()
   async eas_schema(@Root() attestation: Attestation) {
-    if (!attestation.supported_schemas_id) return;
+    try {
+      if (!attestation.supported_schemas_id) return null;
 
-    return await this.attestationSchemaService.getAttestationSchema({
-      where: {
-        id: { eq: attestation.supported_schemas_id },
-      },
-    });
+      return await this.attestationSchemaService.getAttestationSchema({
+        where: {
+          id: { eq: attestation.supported_schemas_id },
+        },
+      });
+    } catch (e) {
+      console.error(
+        `[AttestationResolver::eas_schema] Error fetching eas_schema: ${(e as Error).message}`,
+      );
+      return null;
+    }
   }
 
   /**
@@ -263,17 +281,24 @@ class AttestationResolver {
   //TODO: Should this be part of the resolved hypercert data?
   @FieldResolver()
   async metadata(@Root() attestation: Attestation) {
-    if (!attestation.data) return;
+    try {
+      if (!attestation.data) return null;
 
-    const attested_hypercert_id = this.getHypercertIdFromAttestationData(
-      attestation.data,
-    );
+      const attested_hypercert_id = this.getHypercertIdFromAttestationData(
+        attestation.data,
+      );
 
-    if (!attested_hypercert_id) return;
+      if (!attested_hypercert_id) return null;
 
-    return await this.metadataService.getMetadataSingle({
-      where: { hypercerts: { hypercert_id: { eq: attested_hypercert_id } } },
-    });
+      return await this.metadataService.getMetadataSingle({
+        where: { hypercerts: { hypercert_id: { eq: attested_hypercert_id } } },
+      });
+    } catch (e) {
+      console.error(
+        `[AttestationResolver::metadata] Error fetching metadata: ${(e as Error).message}`,
+      );
+      return null;
+    }
   }
 
   /**
@@ -299,17 +324,22 @@ class AttestationResolver {
    * getHypercertIdFromAttestationData(null) // returns undefined
    * ```
    */
-  getHypercertIdFromAttestationData(
-    attestationData: unknown,
-  ): string | undefined {
-    if (!attestationData) return;
+  getHypercertIdFromAttestationData(attestationData: unknown): string | null {
+    try {
+      if (!attestationData) return null;
 
-    const parseResult = HypercertPointer.safeParse(attestationData);
+      const parseResult = HypercertPointer.safeParse(attestationData);
 
-    if (!parseResult.success) return;
+      if (!parseResult.success) return null;
 
-    const { chain_id, contract_address, token_id } = parseResult.data;
-    return `${chain_id.toString()}-${getAddress(contract_address)}-${token_id.toString()}`;
+      const { chain_id, contract_address, token_id } = parseResult.data;
+      return `${chain_id.toString()}-${getAddress(contract_address)}-${token_id.toString()}`;
+    } catch (e) {
+      console.error(
+        `[AttestationResolver::getHypercertIdFromAttestationData] Error parsing hypercert ID: ${(e as Error).message}`,
+      );
+      return null;
+    }
   }
 }
 

src/services/graphql/resolvers/attestationSchemaResolver.ts

@@ -1,13 +1,13 @@
 import { inject, injectable } from "tsyringe";
 import { Args, FieldResolver, Query, Resolver, Root } from "type-graphql";
-import { AttestationService } from "../../../services/database/entities/AttestationEntityService.js";
-import { AttestationSchemaService } from "../../../services/database/entities/AttestationSchemaEntityService.js";
 import { GetAttestationSchemasArgs } from "../../../graphql/schemas/args/attestationSchemaArgs.js";
-import { GetAttestationsResponse } from "../../../graphql/schemas/typeDefs/attestationTypeDefs.js";
 import {
   AttestationSchema,
   GetAttestationsSchemaResponse,
 } from "../../../graphql/schemas/typeDefs/attestationSchemaTypeDefs.js";
+import { GetAttestationsResponse } from "../../../graphql/schemas/typeDefs/attestationTypeDefs.js";
+import { AttestationService } from "../../../services/database/entities/AttestationEntityService.js";
+import { AttestationSchemaService } from "../../../services/database/entities/AttestationSchemaEntityService.js";
 
 /**
  * GraphQL resolver for AttestationSchema operations.
@@ -44,7 +44,6 @@ class AttestationSchemaResolver {
    * @returns A promise that resolves to an object containing:
    *          - data: Array of attestation schemas matching the query
    *          - count: Total number of matching schemas
-   * @throws {Error} If the schema service query fails
    *
    * @example
    * Query with filtering:
@@ -70,7 +69,14 @@ class AttestationSchemaResolver {
    */
   @Query(() => GetAttestationsSchemaResponse)
   async attestationSchemas(@Args() args: GetAttestationSchemasArgs) {
-    return await this.attestationSchemaService.getAttestationSchemas(args);
+    try {
+      return await this.attestationSchemaService.getAttestationSchemas(args);
+    } catch (e) {
+      console.error(
+        `[AttestationSchemaResolver::attestationSchemas] Error fetching attestation schemas: ${(e as Error).message}`,
+      );
+      return null;
+    }
   }
 
   /**
@@ -107,9 +113,16 @@ class AttestationSchemaResolver {
    */
   @FieldResolver(() => GetAttestationsResponse, { nullable: true })
   async attestations(@Root() schema: Partial<AttestationSchema>) {
-    return await this.attestationService.getAttestations({
-      where: { supported_schemas_id: { eq: schema.id } },
-    });
+    try {
+      return await this.attestationService.getAttestations({
+        where: { supported_schemas_id: { eq: schema.id } },
+      });
+    } catch (e) {
+      console.error(
+        `[AttestationSchemaResolver::attestations] Error fetching attestations: ${(e as Error).message}`,
+      );
+      return null;
+    }
   }
 }
 

src/services/graphql/resolvers/contractResolver.ts

@@ -1,11 +1,11 @@
 import { inject, injectable } from "tsyringe";
 import { Args, Query, Resolver } from "type-graphql";
-import { ContractService } from "../../database/entities/ContractEntityService.js";
 import { GetContractsArgs } from "../../../graphql/schemas/args/contractArgs.js";
 import {
   Contract,
   GetContractsResponse,
 } from "../../../graphql/schemas/typeDefs/contractTypeDefs.js";
+import { ContractService } from "../../database/entities/ContractEntityService.js";
 
 /**
  * GraphQL resolver for Contract operations.
@@ -45,7 +45,6 @@ class ContractResolver {
    * @returns A promise that resolves to an object containing:
    *          - data: Array of contracts matching the query
    *          - count: Total number of matching contracts
-   * @throws {Error} If the contract service query fails
    *
    * @example
    * Query with filtering:
@@ -70,7 +69,14 @@ class ContractResolver {
    */
   @Query(() => GetContractsResponse)
   async contracts(@Args() args: GetContractsArgs) {
-    return this.contractService.getContracts(args);
+    try {
+      return await this.contractService.getContracts(args);
+    } catch (e) {
+      console.error(
+        `[ContractResolver::contracts] Error fetching contracts: ${(e as Error).message}`,
+      );
+      return null;
+    }
   }
 }
 

src/services/graphql/resolvers/fractionResolver.ts

@@ -94,11 +94,7 @@ class FractionResolver {
       console.error(
         `[FractionResolver::fractions] Error fetching fractions: ${(e as Error).message}`,
       );
-      // Return empty result instead of throwing
-      return {
-        data: [],
-        count: 0,
-      };
+      return null;
     }
   }
 
@@ -208,10 +204,7 @@ class FractionResolver {
         `[FractionResolver::orders] Error fetching orders for fraction ${fraction.id}: ${(e as Error).message}`,
       );
       // Return empty result instead of throwing
-      return {
-        data: [],
-        count: 0,
-      };
+      return null;
     }
   }
 
@@ -275,11 +268,7 @@ class FractionResolver {
       console.error(
         `[FractionResolver::sales] Error fetching sales for fraction ${fraction.id}: ${(e as Error).message}`,
       );
-      // Return empty result instead of throwing
-      return {
-        data: [],
-        count: 0,
-      };
+      return null;
     }
   }
 }

test/services/graphql/resolvers/allowlistRecordResolver.test.ts

@@ -80,7 +80,7 @@ describe("AllowlistRecordResolver", () => {
       mockAllowlistRecordService.getAllowlistRecords.mockRejectedValue(error);
 
       // Act & Assert
-      await expect(resolver.allowlistRecords(args)).rejects.toThrow(error);
+      await expect(resolver.allowlistRecords(args)).resolves.toBeNull();
     });
   });
 
@@ -135,7 +135,7 @@ describe("AllowlistRecordResolver", () => {
       mockHypercertsService.getHypercert.mockRejectedValue(error);
 
       // Act & Assert
-      await expect(resolver.hypercert(allowlistRecord)).rejects.toThrow(error);
+      await expect(resolver.hypercert(allowlistRecord)).resolves.toBeNull();
     });
   });
 });