store and expose base schema sdl + hash

Author: n1ru4l

integration-tests/testkit/flow.ts

@@ -1276,6 +1276,8 @@ export function checkSchema(input: SchemaCheckInput, token: string) {
             schemaCheck {
               __typename
               id
+              previousSchemaSDL
+              baseSchemaHash
               schemaVersion {
                 id
               }
@@ -1299,6 +1301,8 @@ export function checkSchema(input: SchemaCheckInput, token: string) {
             }
             schemaCheck {
               id
+              previousSchemaSDL
+              baseSchemaHash
             }
           }
         }

integration-tests/tests/api/schema/check.spec.ts

@@ -2070,6 +2070,7 @@ describe.concurrent('schema check with a base service schema', () => {
       const result = await checkSchema(
         {
           service: 'products',
+          baseSchemaHash: 'base-commit-sha',
           baseSdl: /* GraphQL */ `
             extend schema
               @link(url: "https://specs.apollo.dev/link/v1.0")
@@ -2107,6 +2108,10 @@ describe.concurrent('schema check with a base service schema', () => {
       expect(result.schemaCheck).toMatchObject({
         __typename: 'SchemaCheckError',
         valid: false,
+        schemaCheck: {
+          previousSchemaSDL: expect.stringContaining('baseOnly: String'),
+          baseSchemaHash: 'base-commit-sha',
+        },
         changes: {
           nodes: [
             {

packages/libraries/cli/src/commands/schema/check.ts

@@ -238,10 +238,12 @@ export default class SchemaCheck extends Command<typeof SchemaCheck> {
       }
 
       let minifiedBaseSdl: string | null = null;
+      let baseSchemaHash: string | null = null;
 
       if (flags.base) {
         const basePointer = flags.base;
         const gitResult = parseBaseGitFileReference(basePointer);
+        baseSchemaHash = gitResult.status === 'ok' ? gitResult.commit : null;
         const result =
           gitResult.status === 'error'
             ? await loadSchema('first-federation-then-graphql-introspection', basePointer, {
@@ -346,6 +348,7 @@ export default class SchemaCheck extends Command<typeof SchemaCheck> {
             url: flags.url,
             schemaProposalId: flags.schemaProposalId,
             baseSdl: minifiedBaseSdl,
+            baseSchemaHash,
           },
         },
         /** Gateway timeout is 60 seconds. */

packages/migrations/src/run-pg-migrations.ts

@@ -130,5 +130,6 @@ export const runPGMigrations = async (args: { slonik: PostgresDatabasePool; runT
       import('./actions/2026.06.11T00-00-00.oidc-integration-user-id-claim'),
       import('./actions/2026.08.06T00-00-00.scim-provisioning-status'),
       import('./actions/2026.08.07T00-00-00.scim-pending-confirmation-index'),
+      import('./actions/2026.08.11T00-00-00.schema-check-base-sdl'),
     ]),
   });

packages/services/api/src/modules/schema/module.graphql.ts

@@ -901,6 +901,11 @@ export default gql`
     """
     baseSdl: String
 
+    """
+    An identifier for the schema supplied through 'baseSdl', such as its Git commit SHA.
+    """
+    baseSchemaHash: String
+
     github: GitHubSchemaCheckInput
     meta: SchemaCheckMetaInput
     """
@@ -1446,6 +1451,10 @@ export default gql`
     """
     previousSchemaSDL: String @tag(name: "public")
     """
+    The caller-supplied identifier for an explicit comparison baseline, such as a Git commit SHA.
+    """
+    baseSchemaHash: String @tag(name: "public")
+    """
     The name of the service that owns the schema. Is null for non composite project types.
     """
     serviceName: String @tag(name: "public")
@@ -1603,6 +1612,10 @@ export default gql`
     """
     previousSchemaSDL: String @tag(name: "public")
     """
+    The caller-supplied identifier for an explicit comparison baseline, such as a Git commit SHA.
+    """
+    baseSchemaHash: String @tag(name: "public")
+    """
     The name of the service that owns the schema. Is null for non composite project types.
     """
     serviceName: String @tag(name: "public")
@@ -1704,6 +1717,10 @@ export default gql`
     """
     previousSchemaSDL: String @tag(name: "public")
     """
+    The caller-supplied identifier for an explicit comparison baseline, such as a Git commit SHA.
+    """
+    baseSchemaHash: String @tag(name: "public")
+    """
     The name of the service that owns the schema. Is null for non composite project types.
     """
     serviceName: String @tag(name: "public")

packages/services/api/src/modules/schema/providers/schema-check-manager.ts

@@ -72,6 +72,10 @@ export class SchemaCheckManager {
   }
 
   async getPreviousSchemaSDL(schemaCheck: SchemaCheck) {
+    if (schemaCheck.baseSchemaSDL !== null) {
+      return schemaCheck.baseSchemaSDL;
+    }
+
     if (schemaCheck.serviceName === null || schemaCheck.schemaVersionId === null) {
       return null;
     }

packages/services/api/src/modules/schema/providers/schema-publisher.ts

@@ -580,6 +580,7 @@ export class SchemaPublisher {
 
     const sdl = tryPrettifySDL(input.sdl);
     const baseSdl = input.baseSdl ? tryPrettifySDL(input.baseSdl) : null;
+    const baseSchemaHash = baseSdl ? (input.baseSchemaHash ?? null) : null;
 
     const activeContracts =
       project.type === ProjectType.FEDERATION
@@ -775,6 +776,8 @@ export class SchemaPublisher {
     if (checkResult.conclusion === SchemaCheckConclusion.Failure) {
       schemaCheck = await this.storage.createSchemaCheck({
         schemaSDL: sdl,
+        baseSchemaSDL: baseSdl,
+        baseSchemaHash,
         serviceName: input.service ?? null,
         serviceUrl: input.url ?? null,
         meta: input.meta ?? null,
@@ -831,6 +834,8 @@ export class SchemaPublisher {
     } else if (checkResult.conclusion === SchemaCheckConclusion.Success) {
       schemaCheck = await this.storage.createSchemaCheck({
         schemaSDL: sdl,
+        baseSchemaSDL: baseSdl,
+        baseSchemaHash,
         serviceName: input.service ?? null,
         serviceUrl: input.url ?? null,
         meta: input.meta ?? null,
@@ -889,6 +894,8 @@ export class SchemaPublisher {
 
       schemaCheck = await this.storage.createSchemaCheck({
         schemaSDL: sdl,
+        baseSchemaSDL: baseSdl,
+        baseSchemaHash,
         serviceName: input.service ?? null,
         serviceUrl: input.url ?? null,
         meta: input.meta ?? null,

packages/services/storage/src/db/types.ts

@@ -402,6 +402,8 @@ export interface schema_change_approvals {
 }
 
 export interface schema_checks {
+  base_schema_hash: string | null;
+  base_schema_sdl_store_id: string | null;
   breaking_schema_changes: any | null;
   composite_schema_sdl: string | null;
   composite_schema_sdl_store_id: string | null;

packages/services/storage/src/index.ts

@@ -3092,11 +3092,16 @@ export async function createStorage(
         }
 
         const schemaSDLHash = createSDLHash(args.schemaSDL);
+        const baseSchemaSDLHash = args.baseSchemaSDL ? createSDLHash(args.baseSchemaSDL) : null;
         let compositeSchemaSDLHash: string | null = null;
         let supergraphSDLHash: string | null = null;
 
         sdlStoreInserts.push(insertSdl(schemaSDLHash, args.schemaSDL));
 
+        if (args.baseSchemaSDL && baseSchemaSDLHash) {
+          sdlStoreInserts.push(insertSdl(baseSchemaSDLHash, args.baseSchemaSDL));
+        }
+
         if (args.compositeSchemaSDL) {
           compositeSchemaSDLHash = createSDLHash(args.compositeSchemaSDL);
           sdlStoreInserts.push(insertSdl(compositeSchemaSDLHash, args.compositeSchemaSDL));
@@ -3114,6 +3119,8 @@ export async function createStorage(
             psql`/* createSchemaCheck */
           INSERT INTO "schema_checks" (
               "schema_sdl_store_id"
+            , "base_schema_sdl_store_id"
+            , "base_schema_hash"
             , "service_name"
             , "service_url"
             , "meta"
@@ -3141,6 +3148,8 @@ export async function createStorage(
           )
           VALUES (
               ${schemaSDLHash}
+            , ${baseSchemaSDLHash}
+            , ${args.baseSchemaHash}
             , ${args.serviceName}
             , ${args.serviceUrl}
             , ${psql.jsonbOrNull(args.meta)}
@@ -3239,6 +3248,7 @@ export async function createStorage(
         FROM
           "schema_checks" as c
         LEFT JOIN "sdl_store" as s_schema            ON s_schema."id" = c."schema_sdl_store_id"
+        LEFT JOIN "sdl_store" as s_base_schema       ON s_base_schema."id" = c."base_schema_sdl_store_id"
         LEFT JOIN "sdl_store" as s_composite_schema  ON s_composite_schema."id" = c."composite_schema_sdl_store_id"
         LEFT JOIN "sdl_store" as s_supergraph        ON s_supergraph."id" = c."supergraph_sdl_store_id"
         WHERE
@@ -3374,6 +3384,7 @@ export async function createStorage(
         FROM
           "schema_checks" as c
         LEFT JOIN "sdl_store" as s_schema            ON s_schema."id" = c."schema_sdl_store_id"
+        LEFT JOIN "sdl_store" as s_base_schema       ON s_base_schema."id" = c."base_schema_sdl_store_id"
         LEFT JOIN "sdl_store" as s_composite_schema  ON s_composite_schema."id" = c."composite_schema_sdl_store_id"
         LEFT JOIN "sdl_store" as s_supergraph        ON s_supergraph."id" = c."supergraph_sdl_store_id"
         WHERE
@@ -3426,6 +3437,7 @@ export async function createStorage(
             args.withSDL
               ? psql`
                   LEFT JOIN "sdl_store" as s_schema            ON s_schema."id" = c."schema_sdl_store_id"
+                  LEFT JOIN "sdl_store" as s_base_schema       ON s_base_schema."id" = c."base_schema_sdl_store_id"
                   LEFT JOIN "sdl_store" as s_composite_schema  ON s_composite_schema."id" = c."composite_schema_sdl_store_id"
                   LEFT JOIN "sdl_store" as s_supergraph        ON s_supergraph."id" = c."supergraph_sdl_store_id"
                 `
@@ -3554,6 +3566,8 @@ export async function createStorage(
         }
         LEFT JOIN "sdl_store" as s_schema
           ON s_schema."id" = c."schema_sdl_store_id"
+        LEFT JOIN "sdl_store" as s_base_schema
+          ON s_base_schema."id" = c."base_schema_sdl_store_id"
         LEFT JOIN "sdl_store" as s_composite_schema
           ON s_composite_schema."id" = c."composite_schema_sdl_store_id"
         LEFT JOIN "sdl_store" as s_supergraph
@@ -3707,6 +3721,10 @@ export async function createStorage(
               FROM "filtered_schema_checks"
               WHERE "filtered_schema_checks"."schema_sdl_store_id" IS NOT NULL
 
+              UNION SELECT DISTINCT "filtered_schema_checks"."base_schema_sdl_store_id"
+              FROM "filtered_schema_checks"
+              WHERE "filtered_schema_checks"."base_schema_sdl_store_id" IS NOT NULL
+
               UNION SELECT DISTINCT "filtered_schema_checks"."composite_schema_sdl_store_id"
               FROM "filtered_schema_checks"
               WHERE "filtered_schema_checks"."composite_schema_sdl_store_id" IS NOT NULL
@@ -3777,6 +3795,7 @@ export async function createStorage(
                     "schema_checks"
                   WHERE
                     "schema_checks"."schema_sdl_store_id" = "sdl_store"."id"
+                    OR "schema_checks"."base_schema_sdl_store_id" = "sdl_store"."id"
                     OR "schema_checks"."composite_schema_sdl_store_id" = "sdl_store"."id"
                     OR "schema_checks"."supergraph_sdl_store_id" = "sdl_store"."id"
                 )
@@ -4212,16 +4231,19 @@ const schemaCheckSQLFields = (include?: { sdl?: boolean; changes?: boolean }) =>
     (include?.sdl ?? true)
       ? psql`
         , coalesce(c."schema_sdl", s_schema."sdl") as "schemaSDL"
+        , s_base_schema."sdl" as "baseSchemaSDL"
         , coalesce(c."composite_schema_sdl", s_composite_schema."sdl") as "compositeSchemaSDL"
         , coalesce(c."supergraph_sdl", s_supergraph."sdl") as "supergraphSDL"
       `
       : psql`
         , '' as "schemaSDL"
+        , null as "baseSchemaSDL"
         , null as "compositeSchemaSDL"
         , null as "supergraphSDL"
       `
   }
   , c."service_name" as "serviceName"
+  , c."base_schema_hash" as "baseSchemaHash"
   , c."service_url" as "serviceUrl"
   , c."meta"
   , c."target_id" as "targetId"

packages/services/storage/src/schema-change-model.ts

@@ -1448,7 +1448,7 @@ const SchemaProposalOutputFields = {
   schemaProposalChanges: z.array(HiveSchemaChangeModel).nullable(),
 };
 
-const SchemaCheckSharedOutputFields = {
+const SchemaCheckCommonFields = {
   schemaSDL: z.string(),
   serviceName: z.string().nullable(),
   serviceUrl: z.string().nullable(),
@@ -1470,8 +1470,24 @@ const SchemaCheckSharedOutputFields = {
   ...SchemaProposalOutputFields,
 };
 
+const SchemaCheckSharedOutputFields = {
+  ...SchemaCheckCommonFields,
+  baseSchemaSDL: z.string().nullable(),
+  baseSchemaHash: z.string().nullable(),
+};
+
 const SchemaCheckSharedInputFields = {
-  ...SchemaCheckSharedOutputFields,
+  ...SchemaCheckCommonFields,
+  baseSchemaSDL: z
+    .string()
+    .nullable()
+    .optional()
+    .transform(value => value ?? null),
+  baseSchemaHash: z
+    .string()
+    .nullable()
+    .optional()
+    .transform(value => value ?? null),
 };
 
 const ContractCheckInput = z.object({