test: add serialization test

artsy · Nov 24, 2024 · 112329a · 112329a
1 parent 6f9a1ad
commit 112329a
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Showing 4 changed files with 102 additions and 22 deletions.
diff --git a/src/System/Router/Utils/__tests__/renderToStream.jest.tsx b/src/System/Router/Utils/__tests__/renderToStream.jest.tsx
@@ -15,6 +15,7 @@ describe("renderToStream", () => {
   const res = ({
     statusCode: 0,
     setHeader: jest.fn(),
+    res: { write: jest.fn(), end: jest.fn() },
   } as unknown) as ArtsyResponse
 
   const sheet = ({
@@ -109,7 +110,7 @@ describe("renderToStream", () => {
     const jsx = <div>Timeout Test</div>
     renderToStream({ jsx, sheet, res })
 
-    jest.advanceTimersByTime(5000)
+    jest.advanceTimersByTime(10000) // stream timeout
 
     expect(mockAbort).toHaveBeenCalled()
     jest.useRealTimers()
@@ -142,6 +143,8 @@ describe("renderToStream", () => {
       )
     })
 
+    await flushPromiseQueue()
+
     stream.end()
   })
 
@@ -161,20 +164,22 @@ describe("renderToStream", () => {
 
     const stream = renderToStream({ jsx, sheet, res })
 
-    stream.write("<html><head></head><body></body></html>")
+    stream.write("<html><head></head><body>")
 
     const chunks: string[] = []
     stream.on("data", chunk => {
       chunks.push(chunk)
     })
 
-    await new Promise(resolve => {
-      stream.on("end", resolve)
+    stream.on("end", () => {
+      const result = chunks.join("")
+      expect(result).toContain(
+        '<html><head>mock-css</head><body><div class="content">Hello World</div>'
+      )
     })
 
-    const result = chunks.join("")
-    expect(result).toContain(
-      '<html><head>mock-css</head><body></body></html><div class="content">Hello World</div>'
-    )
+    await flushPromiseQueue()
+
+    stream.end()
   })
 })
diff --git a/src/System/Router/Utils/__tests__/serializeRelayHydrationData.jest.ts b/src/System/Router/Utils/__tests__/serializeRelayHydrationData.jest.ts
@@ -0,0 +1,78 @@
+import { SSRCache } from "react-relay-network-modern-ssr/lib/server"
+import { serializeRelayHydrationData } from "System/Router/Utils/serializeRelayHydrationData"
+import mockSerialize from "serialize-javascript"
+
+jest.mock("serialize-javascript", () => jest.fn())
+
+describe("serializeRelayHydrationData", () => {
+  afterEach(() => {
+    jest.clearAllMocks()
+  })
+
+  it("should serialize the relay data correctly", () => {
+    const mockData = ([
+      [
+        {
+          id: 1,
+          _res: "some-network-response",
+          data: "value1",
+        },
+        {
+          id: 2,
+          _res: "another-response",
+          data: "value2",
+        },
+      ],
+    ] as unknown) as SSRCache
+
+    mockSerialize.mockImplementation((data, options) => JSON.stringify(data))
+
+    const result = serializeRelayHydrationData(mockData)
+
+    expect(mockSerialize).toHaveBeenCalledTimes(2)
+    expect(mockSerialize).toHaveBeenCalledWith(mockData, { isJSON: true })
+    expect(mockSerialize).toHaveBeenCalledWith(JSON.stringify(mockData), {
+      isJSON: true,
+    })
+
+    expect(result).toBe(JSON.stringify(JSON.stringify(mockData)))
+    expect(mockData[0][0]).not.toHaveProperty("_res")
+    expect(mockData[0][1]).not.toHaveProperty("_res")
+  })
+
+  it("should handle empty data gracefully", () => {
+    mockSerialize.mockImplementation((data, options) => JSON.stringify(data))
+
+    const result = serializeRelayHydrationData([])
+
+    expect(mockSerialize).toHaveBeenCalledTimes(2)
+    expect(mockSerialize).toHaveBeenCalledWith([], { isJSON: true })
+    expect(mockSerialize).toHaveBeenCalledWith(JSON.stringify([]), {
+      isJSON: true,
+    })
+
+    expect(result).toBe(JSON.stringify(JSON.stringify([])))
+  })
+
+  it("should return an empty serialized array when an error occurs", () => {
+    const mockData = ([
+      [
+        {
+          id: 1,
+          _res: "some-network-response",
+          data: "value1",
+        },
+      ],
+    ] as unknown) as SSRCache
+
+    mockSerialize.mockImplementation(() => {
+      throw new Error("Serialization Error")
+    })
+
+    expect(() => {
+      const result = serializeRelayHydrationData(mockData)
+      expect(mockSerialize).toHaveBeenCalledTimes(1)
+      expect(result).toBe(mockSerialize("[]", { isJSON: true }))
+    }).toThrowError("Serialization Error")
+  })
+})
diff --git a/src/System/Router/Utils/renderToStream.tsx b/src/System/Router/Utils/renderToStream.tsx
@@ -4,7 +4,7 @@ import { ArtsyResponse } from "Server/middleware/artsyExpress"
 import { Transform } from "stream"
 import { ServerStyleSheet } from "styled-components"
 
-const STREAM_TIMEOUT = 5000
+const STREAM_TIMEOUT_MS = 10000
 
 interface RenderToStreamProps {
   jsx: ReactNode
@@ -80,7 +80,7 @@ export const renderToStream = ({
   // Abandon and switch to client rendering if enough time passes.
   streamTimeout = setTimeout(() => {
     abort()
-  }, STREAM_TIMEOUT)
+  }, STREAM_TIMEOUT_MS)
 
   return stream
 }
diff --git a/src/System/Router/Utils/serializeRelayHydrationData.tsx b/src/System/Router/Utils/serializeRelayHydrationData.tsx
@@ -2,30 +2,27 @@ import { RelayNetworkLayerResponse } from "react-relay-network-modern"
 import { SSRCache } from "react-relay-network-modern-ssr/lib/server"
 import serialize from "serialize-javascript"
 
-export const serializeRelayHydrationData = (initialRelayData: SSRCache) => {
+export const serializeRelayHydrationData = (
+  initialRelayData: SSRCache = []
+): string => {
   initialRelayData.forEach(entry => {
     entry.forEach((item: RelayNetworkLayerResponse) => {
-      // Clean relay data of problematic data structures
-      delete item._res
+      delete item._res // Remove unnecessary relay network data
     })
   })
 
-  let hydrationData
-
   try {
-    hydrationData = serialize(initialRelayData, {
+    // Double pass to ensure that the data is serialized correctly
+    // TODO: Fix this
+    return serialize(serialize(initialRelayData, { isJSON: true }), {
       isJSON: true,
     })
   } catch (error) {
-    hydrationData = "{}"
-
     console.error(
       "[system/router/serializeRelayHydrationData] Error serializing data:",
       error
     )
-  }
 
-  return serialize(hydrationData || {}, {
-    isJSON: true,
-  })
+    return serialize("[]", { isJSON: true })
+  }
 }