Fix TypeError When Using @Paginate() with @MessagePattern() (@nestjs/microservices)

src/decorator.spec.ts

@@ -1,5 +1,5 @@
 import { ROUTE_ARGS_METADATA } from '@nestjs/common/constants'
-import { HttpArgumentsHost, CustomParamFactory, ExecutionContext } from '@nestjs/common/interfaces'
+import { CustomParamFactory, ExecutionContext, HttpArgumentsHost } from '@nestjs/common/interfaces'
 import { Request as ExpressRequest } from 'express'
 import { FastifyRequest } from 'fastify'
 import { Paginate, PaginateQuery } from './decorator'
@@ -18,6 +18,7 @@ const decoratorfactory = getParamDecoratorFactory<PaginateQuery>(Paginate)
 
 function expressContextFactory(query: ExpressRequest['query']): Partial<ExecutionContext> {
     const mockContext: Partial<ExecutionContext> = {
+        getType: <ContextType>() => 'http' as ContextType,
         switchToHttp: (): HttpArgumentsHost =>
             Object({
                 getRequest: (): Partial<ExpressRequest> =>
@@ -34,6 +35,7 @@ function expressContextFactory(query: ExpressRequest['query']): Partial<Executio
 
 function fastifyContextFactory(query: FastifyRequest['query']): Partial<ExecutionContext> {
     const mockContext: Partial<ExecutionContext> = {
+        getType: <ContextType>() => 'http' as ContextType,
         switchToHttp: (): HttpArgumentsHost =>
             Object({
                 getRequest: (): Partial<FastifyRequest> =>

src/decorator.ts

@@ -1,7 +1,7 @@
 import { createParamDecorator, ExecutionContext } from '@nestjs/common'
 import type { Request as ExpressRequest } from 'express'
 import type { FastifyRequest } from 'fastify'
-import { pickBy, Dictionary, isString, mapKeys } from 'lodash'
+import { Dictionary, isString, mapKeys, pickBy } from 'lodash'
 
 function isRecord(data: unknown): data is Record<string, unknown> {
     return data !== null && typeof data === 'object' && !Array.isArray(data)
@@ -50,18 +50,34 @@ function parseParam<T>(queryParam: unknown, parserLogic: (param: string, res: an
 }
 
 export const Paginate = createParamDecorator((_data: unknown, ctx: ExecutionContext): PaginateQuery => {
-    const request: ExpressRequest | FastifyRequest = ctx.switchToHttp().getRequest()
-    const query = request.query as Record<string, unknown>
+    let path: string
+    let query: Record<string, unknown>
 
-    // Determine if Express or Fastify to rebuild the original url and reduce down to protocol, host and base url
-    let originalUrl: string
-    if (isExpressRequest(request)) {
-        originalUrl = request.protocol + '://' + request.get('host') + request.originalUrl
-    } else {
-        originalUrl = request.protocol + '://' + request.hostname + request.url
+    switch (ctx.getType()) {
+        case 'http':
+            const request: ExpressRequest | FastifyRequest = ctx.switchToHttp().getRequest()
+            query = request.query as Record<string, unknown>
+
+            // Determine if Express or Fastify to rebuild the original url and reduce down to protocol, host and base url
+            let originalUrl: string
+            if (isExpressRequest(request)) {
+                originalUrl = request.protocol + '://' + request.get('host') + request.originalUrl
+            } else {
+                originalUrl = request.protocol + '://' + request.hostname + request.url
+            }
+
+            const urlParts = new URL(originalUrl)
+            path = urlParts.protocol + '//' + urlParts.host + urlParts.pathname
+            break
+        case 'ws':
+            query = ctx.switchToWs().getData()
+            path = null
+            break
+        case 'rpc':
+            query = ctx.switchToRpc().getData()
+            path = null
+            break
     }
-    const urlParts = new URL(originalUrl)
-    const path = urlParts.protocol + '//' + urlParts.host + urlParts.pathname
 
     const searchBy = parseParam<string>(query.searchBy, singleSplit)
     const sortBy = parseParam<[string, string]>(query.sortBy, multipleSplit)

src/paginate.ts

@@ -355,16 +355,6 @@ export async function paginate<T extends ObjectLiteral>(
         items = await queryBuilder.getMany()
     }
 
-    let path: string
-    const { queryOrigin, queryPath } = getQueryUrlComponents(query.path)
-    if (config.relativePath) {
-        path = queryPath
-    } else if (config.origin) {
-        path = config.origin + queryPath
-    } else {
-        path = queryOrigin + queryPath
-    }
-
     const sortByQuery = sortBy.map((order) => `&sortBy=${order.join(':')}`).join('')
     const searchQuery = query.search ? `&search=${query.search}` : ''
 
@@ -389,6 +379,18 @@ export async function paginate<T extends ObjectLiteral>(
 
     const options = `&limit=${limit}${sortByQuery}${searchQuery}${searchByQuery}${selectQuery}${filterQuery}`
 
+    let path: string = null
+    if (query.path !== null) {
+        // `query.path` does not exist in RPC/WS requests and is set to null then.
+        const { queryOrigin, queryPath } = getQueryUrlComponents(query.path)
+        if (config.relativePath) {
+            path = queryPath
+        } else if (config.origin) {
+            path = config.origin + queryPath
+        } else {
+            path = queryOrigin + queryPath
+        }
+    }
     const buildLink = (p: number): string => path + '?page=' + p + options
 
     const totalPages = isPaginated ? Math.ceil(totalItems / limit) : 1
@@ -406,13 +408,17 @@ export async function paginate<T extends ObjectLiteral>(
             select: isQuerySelected ? selectParams : undefined,
             filter: query.filter,
         },
-        links: {
-            first: page == 1 ? undefined : buildLink(1),
-            previous: page - 1 < 1 ? undefined : buildLink(page - 1),
-            current: buildLink(page),
-            next: page + 1 > totalPages ? undefined : buildLink(page + 1),
-            last: page == totalPages || !totalItems ? undefined : buildLink(totalPages),
-        },
+        // If there is no `path`, don't build links.
+        links:
+            path !== null
+                ? {
+                      first: page == 1 ? undefined : buildLink(1),
+                      previous: page - 1 < 1 ? undefined : buildLink(page - 1),
+                      current: buildLink(page),
+                      next: page + 1 > totalPages ? undefined : buildLink(page + 1),
+                      last: page == totalPages || !totalItems ? undefined : buildLink(totalPages),
+                  }
+                : ({} as Paginated<T>['links']),
     }
 
     return Object.assign(new Paginated<T>(), results)