feat: add better error typings (#103)

* feat: add better error typings

* fix: update package.lock

* feat: refactor

* feat: update version

* fix: add try/catch and resolve

* fix: error schema

* fix: remove useless try/catch

* fix: add endline after package lock

* fix: add endline after package lock

* feat: rename error methods

* feat: update version of package

libs/iota-browser/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@affinidi-tdk/iota-browser",
-  "version": "0.2.8",
+  "version": "0.2.9",
   "description": "Browser module to fetch data through Affinidi Iota Framework",
   "author": "Affinidi",
   "repository": {

libs/iota-browser/src/helpers/channel-provider.ts

@@ -5,9 +5,18 @@ import { iot, mqtt5 } from 'aws-iot-device-sdk-v2/dist/browser'
 import * as jose from 'jose'
 import { v4 as uuidv4 } from 'uuid'
 import {
+  EventTypes,
   PrepareRequestEvent,
+  SignedRequestEvent,
   SignedRequestEventSchema,
+  SignedRequestJWT,
+  SignedRequestJWTSchema,
 } from '../validators/events'
+import {
+  getUnexpectedErrorMessage,
+  ErrorCode,
+  throwEventParsingError,
+} from '../validators/error'
 
 const DEFAULT_IOT_ENDPOINT =
   'a3sq1vuw0cw9an-ats.iot.ap-southeast-1.amazonaws.com'
@@ -147,6 +156,29 @@ export class ChannelProvider {
     await client.subscribe(packet)
   }
 
+  private getRequest(event: SignedRequestEvent) {
+    let signedRequest: SignedRequestEvent, signedRequestJWT: SignedRequestJWT
+    try {
+      signedRequest = SignedRequestEventSchema.parse(event)
+    } catch (e) {
+      throw Error(getUnexpectedErrorMessage(ErrorCode.SIGNED_REQUEST_EVENT))
+    }
+    try {
+      const claims = jose.decodeJwt(signedRequest.data.jwt)
+      signedRequestJWT = SignedRequestJWTSchema.parse(claims)
+    } catch (e) {
+      throw Error(getUnexpectedErrorMessage(ErrorCode.SIGNED_REQUEST_JWT))
+    }
+    const request: IotaChannelRequest = {
+      correlationId: signedRequest.correlationId,
+      payload: {
+        request: signedRequest.data.jwt,
+        client_id: signedRequestJWT.client_id,
+      },
+    }
+    return request
+  }
+
   async prepareRequest(
     params: PrepareRequestParams,
   ): Promise<IotaChannelRequest> {
@@ -178,30 +210,17 @@ export class ChannelProvider {
             )
             try {
               const event = JSON.parse(raw_data)
-              if (
-                event.eventType === 'signedRequest' &&
-                correlationId === event.correlationId
-              ) {
-                // TODO handle Zod errors gracefully
-                const signedRequest = SignedRequestEventSchema.parse(event)
-                const claims = jose.decodeJwt(signedRequest.data.jwt)
-                // TODO Zod validate JWT
-                if (!claims.client_id && typeof claims.client_id === 'string') {
-                  reject(new Error('Unexpected request claims received'))
-                }
-                const client_id = claims.client_id as string
-                const request: IotaChannelRequest = {
-                  correlationId: signedRequest.correlationId,
-                  payload: {
-                    request: signedRequest.data.jwt,
-                    client_id,
-                  },
-                }
-
+              if (correlationId !== event.correlationId) {
+                return
+              }
+              if (event.eventType === EventTypes.SignedRequest) {
+                const request = this.getRequest(event)
                 resolve(request)
+              } else if (event.eventType === EventTypes.Error) {
+                throwEventParsingError(event)
               }
-            } catch (error) {
-              reject(error)
+            } catch (e) {
+              reject(e)
             }
           }
         },

libs/iota-browser/src/helpers/response-handler.ts

@@ -1,11 +1,18 @@
 import { toUtf8 } from '@aws-sdk/util-utf8-browser'
 import { mqtt5 } from 'aws-iot-device-sdk-v2/dist/browser'
 import {
+  EventTypes,
   ResponseCallbackEventSchema,
   VerifiablePresentation,
   VerifiablePresentationSchema,
+  ResponseCallbackEvent,
 } from '../validators/events'
 import { ChannelProvider } from './channel-provider'
+import {
+  ErrorCode,
+  throwEventParsingError,
+  getUnexpectedErrorMessage,
+} from '../validators/error'
 
 export type IotaResponse = {
   correlationId: string
@@ -26,6 +33,31 @@ export class ResponseHandler {
     this.channelProvider = channelProvider
   }
 
+  private getResponseHandler(event: ResponseCallbackEvent) {
+    let responseCallback: ResponseCallbackEvent, vpToken: VerifiablePresentation
+    try {
+      responseCallback = ResponseCallbackEventSchema.parse(event)
+    } catch (e) {
+      throw Error(getUnexpectedErrorMessage(ErrorCode.RESPONSE_CALLBACK_EVENT))
+    }
+    try {
+      vpToken = VerifiablePresentationSchema.parse(
+        JSON.parse(responseCallback.vpToken),
+      )
+    } catch (e) {
+      throw Error(
+        getUnexpectedErrorMessage(ErrorCode.VERIFIABLE_PRESENTATION_SCHEMA),
+      )
+    }
+    const response: IotaResponse = {
+      correlationId: responseCallback.correlationId,
+      vpToken,
+      // TODO parse presentation submission, same as vpToken
+      presentationSubmission: responseCallback.presentationSubmission,
+    }
+    return response
+  }
+
   async getResponse(correlationId: string): Promise<IotaResponse> {
     const client = this.channelProvider.getClient()
     return new Promise((resolve, reject) => {
@@ -36,27 +68,16 @@ export class ResponseHandler {
             const raw_data = toUtf8(
               messageReceivedEvent.message.payload as Buffer,
             )
-
             try {
               const event = JSON.parse(raw_data)
-              if (
-                event.eventType === 'response-callback' &&
-                event.correlationId === correlationId
-              ) {
-                // TODO handle Zod errors gracefully
-                const responseCallback =
-                  ResponseCallbackEventSchema.parse(event)
-                const vpToken = VerifiablePresentationSchema.parse(
-                  JSON.parse(responseCallback.vpToken),
-                )
-                const response: IotaResponse = {
-                  correlationId: responseCallback.correlationId,
-                  vpToken,
-                  // TODO parse presentation submission, same as vpToken
-                  presentationSubmission:
-                    responseCallback.presentationSubmission,
-                }
+              if (correlationId !== event.correlationId) {
+                return
+              }
+              if (event.eventType === EventTypes.ResponseCallback) {
+                const response = this.getResponseHandler(event)
                 resolve(response)
+              } else if (event.eventType === EventTypes.Error) {
+                throwEventParsingError(event)
               }
             } catch (error) {
               reject(error)

libs/iota-browser/src/validators/error.ts

@@ -0,0 +1,34 @@
+import { ErrorEvent, ErrorEventSchema } from '../validators/events'
+
+export enum ErrorCode {
+  'SIGNED_REQUEST_EVENT' = 'SignedRequestEvent',
+  'SIGNED_REQUEST_JWT' = 'SignedRequestJWT',
+  'RESPONSE_CALLBACK_EVENT' = 'ResponseCallbackEvent',
+  'VERIFIABLE_PRESENTATION_SCHEMA' = 'VerifiablePresentationSchema',
+  'ERROR_EVENT' = 'ErrorEvent',
+}
+
+function getIssue(errorEvent: ErrorEvent) {
+  return errorEvent.error.details![0].issues &&
+    errorEvent.error.details![0].issues.length > 0
+    ? errorEvent.error.details![0].issues
+    : errorEvent.error.message
+}
+
+export function getUnexpectedErrorMessage(code: ErrorCode) {
+  return `Unexpected error occured. Error Code: ${code} `
+}
+
+export function formatEventError(errorEvent: ErrorEvent): string {
+  return `Something went wrong. ${getIssue(errorEvent)}. Error Code ${errorEvent.error.httpStatusCode}`
+}
+
+export function throwEventParsingError(event: ErrorEvent): never {
+  let errorEvent: ErrorEvent
+  try {
+    errorEvent = ErrorEventSchema.parse(event)
+  } catch (e) {
+    throw Error(getUnexpectedErrorMessage(ErrorCode.ERROR_EVENT))
+  }
+  throw Error(formatEventError(errorEvent))
+}

libs/iota-browser/src/validators/events.ts

@@ -1,6 +1,6 @@
 import { z } from 'zod'
 
-const EventTypes = {
+export const EventTypes = {
   PrepareRequest: 'prepareRequest',
   SignedRequest: 'signedRequest',
   ResponseCallback: 'response-callback',
@@ -28,6 +28,11 @@ export const SignedRequestEventSchema = BaseEvent.extend({
 })
 export type SignedRequestEvent = z.infer<typeof SignedRequestEventSchema>
 
+export const SignedRequestJWTSchema = z.object({
+  client_id: z.string(),
+})
+export type SignedRequestJWT = z.infer<typeof SignedRequestJWTSchema>
+
 // TODO full VP schema
 export const VerifiablePresentationSchema = z.object({
   verifiableCredential: z.array(z.object({ credentialSubject: z.any() })),
@@ -45,12 +50,12 @@ export type ResponseCallbackEvent = z.infer<typeof ResponseCallbackEventSchema>
 
 const ERROR_LOCATION = ['body', 'path', 'query'] as const
 const ErrorDetailItem = z.object({
-  issue: z.string(),
+  issues: z.string(),
   field: z.string().optional(),
   value: z.string().optional(),
   location: z.enum(ERROR_LOCATION).optional(),
 })
-const ErrorEventSchema = BaseEvent.extend({
+export const ErrorEventSchema = BaseEvent.extend({
   eventType: z.literal(EventTypes.Error),
   error: z.object({
     message: z.string(),