Removes log from DocumentState (#40)

packages/model-client/src/index.ts

@@ -3,6 +3,7 @@ import {
   SignedEvent,
   createSignedInitEvent,
   decodeMultibaseToJSON,
+  decodeMultibaseToStreamID,
   eventToContainer,
 } from '@ceramic-sdk/events'
 import { StreamID } from '@ceramic-sdk/identifiers'
@@ -69,11 +70,21 @@ export class ModelClient extends StreamClient {
     return getModelStreamID(cid)
   }
 
+  /** Retrieve the stringified model stream ID from a stream */
+  async getDocumentModel(streamID: StreamID | string): Promise<string> {
+    const id =
+      typeof streamID === 'string' ? StreamID.fromString(streamID) : streamID
+    const streamState = await this.getStreamState(id)
+    const stream = decodeMultibaseToStreamID(streamState.dimensions.model)
+    return stream.toString()
+  }
+
   /** Retrieve a model's JSON definition */
   async getModelDefinition(
     streamID: StreamID | string,
   ): Promise<ModelDefinition> {
-    const id = typeof streamID === 'string' ? streamID : streamID.toString() // Convert StreamID to string
+    const id =
+      typeof streamID === 'string' ? StreamID.fromString(streamID) : streamID
     const streamState = await this.getStreamState(id)
     const decodedData = decodeMultibaseToJSON(streamState.data)
       .content as ModelDefinition

packages/model-instance-client/src/client.ts

@@ -4,7 +4,7 @@ import {
   decodeMultibaseToJSON,
   decodeMultibaseToStreamID,
 } from '@ceramic-sdk/events'
-import { CommitID, type StreamID } from '@ceramic-sdk/identifiers'
+import { CommitID, StreamID } from '@ceramic-sdk/identifiers'
 import {
   DocumentEvent,
   getStreamID,
@@ -120,8 +120,10 @@ export class ModelInstanceClient extends StreamClient {
   }
 
   /** Retrieve and return document state */
-  async getDocumentState(streamID: string): Promise<DocumentState> {
-    const streamState = await this.getStreamState(streamID)
+  async getDocumentState(streamID: StreamID | string): Promise<DocumentState> {
+    const id =
+      typeof streamID === 'string' ? StreamID.fromString(streamID) : streamID
+    const streamState = await this.getStreamState(id)
     return this.streamStateToDocumentState(streamState)
   }
 
@@ -133,7 +135,9 @@ export class ModelInstanceClient extends StreamClient {
     let currentId: CommitID
     // If currentState is not provided, fetch the current state
     if (!params.currentState) {
-      const streamState = await this.getStreamState(params.streamID)
+      const streamState = await this.getStreamState(
+        StreamID.fromString(params.streamID),
+      )
       currentState = this.streamStateToDocumentState(streamState)
       currentId = this.getCurrentID(streamState.event_cid)
     } else {

packages/model-instance-client/test/lib.test.ts

@@ -1,6 +1,11 @@
 import { assertSignedEvent, getSignedEventPayload } from '@ceramic-sdk/events'
 import type { CeramicClient } from '@ceramic-sdk/http-client'
-import { CommitID, randomCID, randomStreamID } from '@ceramic-sdk/identifiers'
+import {
+  CommitID,
+  StreamID,
+  randomCID,
+  randomStreamID,
+} from '@ceramic-sdk/identifiers'
 import {
   DataInitEventPayload,
   DocumentDataEventPayload,
@@ -250,7 +255,9 @@ describe('ModelInstanceClient', () => {
       } as unknown as CeramicClient
       const client = new ModelInstanceClient({ ceramic, did: authenticatedDID })
 
-      const documentState = await client.getDocumentState(streamId)
+      const documentState = await client.getDocumentState(
+        StreamID.fromString(streamId),
+      )
       expect(documentState.content).toEqual(docState.content)
       expect(documentState.metadata.model.toString()).toEqual(
         docState.metadata.model,

packages/model-instance-handler/src/assertions.ts

@@ -1,6 +1,4 @@
-import type { TimeEvent } from '@ceramic-sdk/events'
 import type {
-  DocumentDataEventPayload,
   DocumentInitEventHeader,
   DocumentMetadata,
   JSONPatchOperation,
@@ -10,7 +8,7 @@ import addFormats from 'ajv-formats'
 import Ajv from 'ajv/dist/2020.js'
 import { equals } from 'uint8arrays'
 
-import type { DocumentState, UnknownContent } from './types.js'
+import type { UnknownContent } from './types.js'
 import { getUniqueFieldsValue } from './utils.js'
 
 const validator = new Ajv({
@@ -135,39 +133,3 @@ export function assertValidUniqueValue(
     )
   }
 }
-
-/**
- * Asserts that the 'id' and 'prev' properties of the given event properly link to the tip of
- * the given document state.
- *
- * By the time the code gets into a StreamtypeHandler's applyCommit function the link to the state
- * should already have been established by the stream loading and conflict resolution code, so
- * if this check were to fail as part of a StreamtypeHandler's applyCommit function, that would
- * indicate a programming error.
- */
-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.toString() !== initCID) {
-    throw new Error(
-      `Invalid init CID in event payload for document, expected ${initCID} but got ${payload.id}`,
-    )
-  }
-
-  const prev = payload.prev.toString()
-  const expectedPrev = state.log[state.log.length - 1]
-  if (prev !== expectedPrev) {
-    throw new Error(
-      `Commit doesn't properly point to previous event payload in log for document ${initCID}. Expected ${expectedPrev}, found 'prev' ${prev}`,
-    )
-  }
-}

packages/model-instance-handler/src/handlers.ts

@@ -10,7 +10,6 @@ import {
 import jsonpatch from 'fast-json-patch'
 
 import {
-  assertEventLinksToState,
   assertNoImmutableFieldChange,
   assertValidContent,
   assertValidInitHeader,
@@ -22,7 +21,6 @@ import { getImmutableFieldsToCheck } from './utils.js'
 import { validateRelationsContent } from './validation.js'
 
 function createInitState(
-  cid: string,
   header: DocumentInitEventHeader,
   content: Record<string, unknown> | null,
 ): DocumentState {
@@ -35,12 +33,10 @@ function createInitState(
       context: header.context,
       shouldIndex: header.shouldIndex,
     },
-    log: [cid],
   }
 }
 
 export async function handleDeterministicInitPayload(
-  cid: string,
   payload: DeterministicInitEventPayload,
   context: Context,
 ): Promise<DocumentState> {
@@ -55,11 +51,10 @@ export async function handleDeterministicInitPayload(
   const definition = await context.getModelDefinition(modelID)
   assertValidInitHeader(definition, header)
 
-  return createInitState(cid, header, null)
+  return createInitState(header, null)
 }
 
 export async function handleInitPayload(
-  cid: string,
   payload: DocumentInitEventPayload,
   context: Context,
 ): Promise<DocumentState> {
@@ -78,17 +73,15 @@ export async function handleInitPayload(
   assertValidContent(modelID, definition.schema, data)
   await validateRelationsContent(context, definition, data)
 
-  return createInitState(cid, header, data)
+  return createInitState(header, data)
 }
 
 export async function handleDataPayload(
-  cid: string,
   payload: DocumentDataEventPayload,
   context: Context,
 ): Promise<DocumentState> {
   const streamID = getStreamID(payload.id).toString()
   const state = await context.getDocumentState(streamID)
-  assertEventLinksToState(payload, state)
 
   const metadata = { ...state.metadata }
 
@@ -131,22 +124,19 @@ export async function handleDataPayload(
   // Validate relations
   await validateRelationsContent(context, definition, content)
 
-  return { content, metadata, log: [...state.log, cid] }
+  return { content, metadata }
 }
 
 export async function handleTimeEvent(
-  cid: string,
   event: TimeEvent,
   context: Context,
 ): Promise<DocumentState> {
   const streamID = getStreamID(event.id).toString()
   const state = await context.getDocumentState(streamID)
-  assertEventLinksToState(event, state)
-  return { ...state, log: [...state.log, cid] }
+  return { ...state }
 }
 
 export async function handleEvent(
-  cid: string,
   event: DocumentEvent,
   context: Context,
 ): Promise<DocumentState> {
@@ -158,15 +148,15 @@ export async function handleEvent(
   if (container.signed) {
     // Signed event is either non-deterministic init or data
     if (DocumentDataEventPayload.is(container.payload)) {
-      return await handleDataPayload(cid, container.payload, context)
+      return await handleDataPayload(container.payload, context)
     }
     if (DocumentInitEventPayload.is(container.payload)) {
-      return await handleInitPayload(cid, container.payload, context)
+      return await handleInitPayload(container.payload, context)
     }
   }
   // Unsigned event is either deterministic init or time
   if (TimeEvent.is(container.payload)) {
-    return await handleTimeEvent(cid, container.payload as TimeEvent, context)
+    return await handleTimeEvent(container.payload as TimeEvent, context)
   }
-  return await handleDeterministicInitPayload(cid, container.payload, context)
+  return await handleDeterministicInitPayload(container.payload, context)
 }

packages/model-instance-handler/src/types.ts

@@ -7,7 +7,6 @@ export type UnknownContent = Record<string, unknown>
 export type DocumentState = {
   content: UnknownContent | null
   metadata: DocumentMetadata
-  log: [string, ...Array<string>]
 }
 
 export type Context = {

packages/model-instance-handler/src/utils.ts

@@ -1,4 +1,3 @@
-import { DocumentDataEventPayload } from '@ceramic-sdk/model-instance-protocol'
 import type { ModelDefinition } from '@ceramic-sdk/model-protocol'
 import { fromString as bytesFromString } from 'uint8arrays'
 
@@ -22,9 +21,7 @@ export function getImmutableFieldsToCheck(
   // Check if the stream is deterministic
   if (['set', 'single'].includes(definition.accountRelation.type)) {
     // Should check immutable fields if there is already a data event present, otherwise it is the first data event that sets the content of the deterministic stream
-    return state.log.some(DocumentDataEventPayload.is)
-      ? definition.immutableFields
-      : []
+    return state.content != null ? definition.immutableFields : []
   }
 
   // Should check immutable fields for all data events on non-deterministic streams

packages/model-instance-handler/test/assertions.test.ts

@@ -7,7 +7,6 @@ import type {
 import type { ModelDefinitionV2 } from '@ceramic-sdk/model-protocol'
 
 import {
-  assertEventLinksToState,
   assertNoImmutableFieldChange,
   assertValidContent,
   assertValidInitHeader,
@@ -16,47 +15,6 @@ import {
 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,
-        { 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().toString()
-    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, expected ${expectedID} but got ${invalidID}`,
-    )
-  })
-
-  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.toString(), expectedID.toString()],
-        } as unknown as DocumentState,
-      )
-    }).toThrow(
-      `Commit doesn't properly point to previous event payload in log for document ${initID}. Expected ${expectedID}, found 'prev' ${invalidID}`,
-    )
-  })
-})
-
 describe('assertNoImmutableFieldChange()', () => {
   test('throws if an immutable field is changed', () => {
     expect(() => {