Add tests for MID events handling

package.json

@@ -10,18 +10,18 @@
     "test:ci": "turbo run test:ci -- --passWithNoTests"
   },
   "devDependencies": {
-    "@biomejs/biome": "1.8.1",
+    "@biomejs/biome": "1.8.2",
     "@jest/globals": "^29.7.0",
     "@swc/cli": "^0.3.12",
     "@swc/core": "^1.6.3",
     "@swc/jest": "^0.2.36",
     "@types/jest": "^29.5.12",
-    "@types/node": "^20.14.5",
+    "@types/node": "^20.14.7",
     "del-cli": "^5.1.0",
     "jest": "^29.7.0",
-    "tsx": "^4.15.6",
+    "tsx": "^4.15.7",
     "turbo": "^2.0.4",
-    "typescript": "^5.4.5"
+    "typescript": "^5.5.2"
   },
   "pnpm": {
     "overrides": {}

packages/document-handler/src/assertions.ts

@@ -150,28 +150,26 @@ export function assertEventLinksToState(
   payload: DocumentDataEventPayload | TimeEvent,
   state: DocumentState,
 ) {
+  if (state.log.length === 0) {
+    throw new Error('Invalid document state: log is empty')
+  }
+
+  const initCID = state.log[0]
+
   // Older versions of the CAS created time events without an 'id' field, so only check
   // the event payload 'id' field if it is present.
-  if (payload.id != null && !payload.id.equals(state.cid)) {
+  if (payload.id != null && !payload.id.equals(initCID)) {
     throw new Error(
-      `Invalid genesis CID in event payload for document ${getStreamID(state.cid)}. Found: ${
+      `Invalid init CID in event payload for document ${getStreamID(initCID)}. Found: ${
         payload.id
-      }, expected ${state.cid}`,
-    )
-  }
-
-  const [init, ...changes] = state.log
-  if (init == null) {
-    throw new Error(
-      `Invalid state for document ${getStreamID(state.cid)}: log is empty`,
+      }, expected ${initCID}`,
     )
   }
 
-  const expectedPrev =
-    changes.length === 0 ? state.cid : changes[changes.length - 1].id
+  const expectedPrev = state.log[state.log.length - 1]
   if (!payload.prev.equals(expectedPrev)) {
     throw new Error(
-      `Commit doesn't properly point to previous event payload in log for document ${getStreamID(state.cid)}. Expected ${expectedPrev}, found 'prev' ${payload.prev}`,
+      `Commit doesn't properly point to previous event payload in log for document ${getStreamID(initCID)}. Expected ${expectedPrev}, found 'prev' ${payload.prev}`,
     )
   }
 }

packages/document-handler/src/codecs.ts

@@ -4,7 +4,7 @@ import {
   DocumentInitEventPayload,
 } from '@ceramic-sdk/document-protocol'
 import { SignedEvent, TimeEvent } from '@ceramic-sdk/events'
-import { type TypeOf, union } from 'codeco'
+import { type OutputOf, type TypeOf, union } from 'codeco'
 import 'ts-essentials' // Import needed for TS reference
 
 export const DocumentEvent = union(
@@ -15,7 +15,7 @@ export const DocumentEvent = union(
   ],
   'DocumentEvent',
 )
-export type DocumentEvent = TypeOf<typeof DocumentEvent>
+export type DocumentEvent = OutputOf<typeof DocumentEvent>
 
 export const DocumentEventPayload = union(
   [

packages/document-handler/src/handlers.ts

@@ -29,7 +29,7 @@ export async function handleDeterministicInitPayload(
   const { data, header } = payload
   if (data !== null) {
     throw new Error(
-      'Deterministic init commits for ModelInstanceDocuments must not have content',
+      'Deterministic init events for ModelInstanceDocuments must not have content',
     )
   }
 
@@ -38,14 +38,13 @@ export async function handleDeterministicInitPayload(
   assertValidInitHeader(definition, header)
 
   return {
-    cid,
     content: null,
     metadata: {
       controller: header.controllers[0],
       model: header.model,
       unique: header.unique,
     },
-    log: [payload],
+    log: [cid],
   }
 }
 
@@ -55,6 +54,11 @@ export async function handleInitPayload(
   context: Context,
 ): Promise<DocumentState> {
   const { data, header } = payload
+  if (data == null) {
+    throw new Error(
+      'Signed init events for ModelInstanceDocuments must have content',
+    )
+  }
   assertValidContentLength(data)
 
   const modelID = header.model.toString()
@@ -65,7 +69,6 @@ export async function handleInitPayload(
   await validateRelationsContent(context, definition, data)
 
   return {
-    cid,
     content: data,
     metadata: {
       controller: header.controllers[0],
@@ -74,17 +77,20 @@ export async function handleInitPayload(
       context: header.context,
       shouldIndex: header.shouldIndex,
     },
-    log: [payload],
+    log: [cid],
   }
 }
 
 export async function handleDataPayload(
+  cid: CID,
   payload: DocumentDataEventPayload,
   context: Context,
 ): Promise<DocumentState> {
   const state = await context.getDocumentState(payload.id)
   assertEventLinksToState(payload, state)
 
+  const metadata = { ...state.metadata }
+
   // Check the header is valid when provided
   if (payload.header != null) {
     const { shouldIndex, ...others } = payload.header
@@ -98,7 +104,7 @@ export async function handleDataPayload(
     }
     // Update metadata if needed
     if (shouldIndex != null) {
-      state.metadata.shouldIndex = shouldIndex
+      metadata.shouldIndex = shouldIndex
     }
   }
 
@@ -124,16 +130,17 @@ export async function handleDataPayload(
   // Validate relations
   await validateRelationsContent(context, definition, content)
 
-  return { ...state, log: [...state.log, payload] }
+  return { content, metadata, log: [...state.log, cid] }
 }
 
 export async function handleTimeEvent(
+  cid: CID,
   event: TimeEvent,
   context: Context,
 ): Promise<DocumentState> {
   const state = await context.getDocumentState(event.id)
   assertEventLinksToState(event, state)
-  return { ...state, log: [...state.log, event] }
+  return { ...state, log: [...state.log, cid] }
 }
 
 export async function handleEvent(
@@ -149,15 +156,15 @@ export async function handleEvent(
   if (container.signed) {
     // Signed event is either non-deterministic init or data
     if (DocumentDataEventPayload.is(container.payload)) {
-      return await handleDataPayload(container.payload, context)
+      return await handleDataPayload(cid, container.payload, context)
     }
     if (DocumentInitEventPayload.is(container.payload)) {
       return await handleInitPayload(cid, container.payload, context)
     }
   }
   // Unsigned event is either deterministic init or time
   if (TimeEvent.is(container.payload)) {
-    return await handleTimeEvent(container.payload as TimeEvent, context)
+    return await handleTimeEvent(cid, container.payload as TimeEvent, context)
   }
   return await handleDeterministicInitPayload(cid, container.payload, context)
 }

packages/document-handler/src/types.ts

@@ -1,33 +1,18 @@
-import type {
-  DeterministicInitEventPayload,
-  DocumentDataEventPayload,
-  DocumentInitEventPayload,
-  DocumentMetadata,
-} from '@ceramic-sdk/document-protocol'
-import type { TimeEvent } from '@ceramic-sdk/events'
+import type { DocumentMetadata } from '@ceramic-sdk/document-protocol'
 import type { ModelDefinition } from '@ceramic-sdk/model-protocol'
 import type { DID } from 'dids'
 import type { CID } from 'multiformats/cid'
 
-export type InitEventPayload =
-  | DeterministicInitEventPayload
-  | DocumentInitEventPayload
-export type ChangeEventPayload = DocumentDataEventPayload | TimeEvent
-
 export type UnknowContent = Record<string, unknown>
 
-export type DocumentSnapshot = {
+export type DocumentState = {
   content: UnknowContent | null
   metadata: DocumentMetadata
-}
-
-export type DocumentState = DocumentSnapshot & {
-  cid: CID
-  log: [InitEventPayload, ...Array<ChangeEventPayload>]
+  log: [CID, ...Array<CID>]
 }
 
 export type Context = {
-  getDocumentSnapshot: (id: string) => Promise<DocumentSnapshot>
+  getDocumentModel: (id: string) => Promise<string>
   getDocumentState: (cid: CID) => Promise<DocumentState>
   getModelDefinition: (id: string) => Promise<ModelDefinition>
   verifier: DID

packages/document-handler/src/validation.ts

@@ -9,10 +9,7 @@ export async function validateRelation(
   expectedModelID: string,
   fieldName: string,
 ): Promise<void> {
-  // Ensure linked stream can be loaded and is a MID
-  const doc = await context.getDocumentSnapshot(docID)
-
-  const modelID = doc.metadata.model.toString()
+  const modelID = await context.getDocumentModel(docID)
   if (modelID === expectedModelID) {
     // Exact model used, relation is valid
     return

packages/document-handler/test/assertions.test.ts

@@ -1,17 +1,61 @@
-import type {
-  DocumentInitEventHeader,
-  DocumentMetadata,
+import {
+  type DocumentDataEventPayload,
+  type DocumentInitEventHeader,
+  type DocumentMetadata,
+  getStreamID,
 } from '@ceramic-sdk/document-protocol'
+import { randomCID } from '@ceramic-sdk/identifiers'
 import type { ModelDefinitionV2 } from '@ceramic-sdk/model-protocol'
 
 import {
+  assertEventLinksToState,
   assertNoImmutableFieldChange,
   assertValidContent,
   assertValidInitHeader,
   assertValidUniqueValue,
 } from '../src/assertions.js'
+import type { DocumentState } from '../src/types.js'
 import { encodeUniqueFieldsValue } from '../src/utils.js'
 
+describe('assertEventLinksToState()', () => {
+  test('throws if the state log is empty', () => {
+    const cid = randomCID()
+    expect(() => {
+      assertEventLinksToState(
+        { id: cid } as unknown as DocumentDataEventPayload,
+        { cid, log: [] } as unknown as DocumentState,
+      )
+    }).toThrow('Invalid document state: log is empty')
+  })
+
+  test('throws if the event id does not match the init event cid', () => {
+    const expectedID = randomCID()
+    const invalidID = randomCID()
+    expect(() => {
+      assertEventLinksToState(
+        { id: invalidID } as unknown as DocumentDataEventPayload,
+        { log: [expectedID] } as unknown as DocumentState,
+      )
+    }).toThrow(
+      `Invalid init CID in event payload for document ${getStreamID(expectedID)}. Found: ${invalidID}, expected ${expectedID}`,
+    )
+  })
+
+  test('throws if the event prev does not match the previous event cid', () => {
+    const initID = randomCID()
+    const expectedID = randomCID()
+    const invalidID = randomCID()
+    expect(() => {
+      assertEventLinksToState(
+        { id: initID, prev: invalidID } as unknown as DocumentDataEventPayload,
+        { log: [initID, expectedID] } as unknown as DocumentState,
+      )
+    }).toThrow(
+      `Commit doesn't properly point to previous event payload in log for document ${getStreamID(initID)}. Expected ${expectedID}, found 'prev' ${invalidID}`,
+    )
+  })
+})
+
 describe('assertNoImmutableFieldChange()', () => {
   test('throws if an immutable field is changed', () => {
     expect(() => {