From 78f9fc2999b15804b02f2c22a2b4007734a26af9 Mon Sep 17 00:00:00 2001
From: Damien Arrachequesne <damien.arrachequesne@gmail.com>
Date: Wed, 7 Oct 2020 18:36:33 +0200
Subject: [PATCH] feat: add support for a payload in a CONNECT packet

---
 dist/index.d.ts     |  1 +
 dist/index.js       | 20 +++++++++++++++++---
 lib/index.ts        | 22 ++++++++++++++++++----
 test/arraybuffer.js |  2 +-
 test/blob.js        |  4 ++--
 test/parser.js      | 17 ++++++++++++++---
 6 files changed, 53 insertions(+), 13 deletions(-)

diff --git a/dist/index.d.ts b/dist/index.d.ts
index 0b88a8a..c2e4753 100644
--- a/dist/index.d.ts
+++ b/dist/index.d.ts
@@ -64,6 +64,7 @@ export declare class Decoder extends Emitter {
      * @return {Object} packet
      */
     private decodeString;
+    private static isPayloadValid;
     /**
      * Deallocates a parser's resources
      */
diff --git a/dist/index.js b/dist/index.js
index b7b716b..69cf092 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -195,9 +195,7 @@ class Decoder extends component_emitter_1.default {
         // look up json data
         if (str.charAt(++i)) {
             const payload = tryParse(str.substr(i));
-            const isPayloadValid = payload !== false &&
-                (p.type === PacketType.ERROR || Array.isArray(payload));
-            if (isPayloadValid) {
+            if (Decoder.isPayloadValid(p.type, payload)) {
                 p.data = payload;
             }
             else {
@@ -207,6 +205,22 @@ class Decoder extends component_emitter_1.default {
         debug("decoded %s as %j", str, p);
         return p;
     }
+    static isPayloadValid(type, payload) {
+        switch (type) {
+            case PacketType.CONNECT:
+                return typeof payload === "object";
+            case PacketType.DISCONNECT:
+                return payload === undefined;
+            case PacketType.ERROR:
+                return typeof payload === "string";
+            case PacketType.EVENT:
+            case PacketType.BINARY_EVENT:
+                return Array.isArray(payload) && typeof payload[0] === "string";
+            case PacketType.ACK:
+            case PacketType.BINARY_ACK:
+                return Array.isArray(payload);
+        }
+    }
     /**
      * Deallocates a parser's resources
      */
diff --git a/lib/index.ts b/lib/index.ts
index a9c9043..ff5671e 100644
--- a/lib/index.ts
+++ b/lib/index.ts
@@ -223,10 +223,7 @@ export class Decoder extends Emitter {
     // look up json data
     if (str.charAt(++i)) {
       const payload = tryParse(str.substr(i));
-      const isPayloadValid =
-        payload !== false &&
-        (p.type === PacketType.ERROR || Array.isArray(payload));
-      if (isPayloadValid) {
+      if (Decoder.isPayloadValid(p.type, payload)) {
         p.data = payload;
       } else {
         throw new Error("invalid payload");
@@ -237,6 +234,23 @@ export class Decoder extends Emitter {
     return p;
   }
 
+  private static isPayloadValid(type: PacketType, payload: any): boolean {
+    switch (type) {
+      case PacketType.CONNECT:
+        return typeof payload === "object";
+      case PacketType.DISCONNECT:
+        return payload === undefined;
+      case PacketType.ERROR:
+        return typeof payload === "string";
+      case PacketType.EVENT:
+      case PacketType.BINARY_EVENT:
+        return Array.isArray(payload) && typeof payload[0] === "string";
+      case PacketType.ACK:
+      case PacketType.BINARY_ACK:
+        return Array.isArray(payload);
+    }
+  }
+
   /**
    * Deallocates a parser's resources
    */
diff --git a/test/arraybuffer.js b/test/arraybuffer.js
index b5df85e..14ef58c 100644
--- a/test/arraybuffer.js
+++ b/test/arraybuffer.js
@@ -57,7 +57,7 @@ describe("parser", () => {
   it("cleans itself up on close", () => {
     const packet = {
       type: PacketType.BINARY_EVENT,
-      data: [new ArrayBuffer(2), new ArrayBuffer(3)],
+      data: ["a", new ArrayBuffer(2), new ArrayBuffer(3)],
       id: 0,
       nsp: "/",
     };
diff --git a/test/blob.js b/test/blob.js
index 43ef584..559d7ef 100644
--- a/test/blob.js
+++ b/test/blob.js
@@ -25,7 +25,7 @@ describe("parser", () => {
 
     const packet = {
       type: PacketType.BINARY_EVENT,
-      data: [data],
+      data: ["a", data],
       id: 0,
       nsp: "/",
     };
@@ -44,7 +44,7 @@ describe("parser", () => {
 
     const packet = {
       type: PacketType.BINARY_EVENT,
-      data: [{ a: "hi", b: { why: data }, c: "bye" }],
+      data: ["a", { a: "hi", b: { why: data }, c: "bye" }],
       id: 999,
       nsp: "/deep",
     };
diff --git a/test/parser.js b/test/parser.js
index f2bd2e9..34d5002 100644
--- a/test/parser.js
+++ b/test/parser.js
@@ -18,6 +18,9 @@ describe("parser", () => {
       {
         type: PacketType.CONNECT,
         nsp: "/woot",
+        data: {
+          token: "123",
+        },
       },
       done
     );
@@ -105,9 +108,17 @@ describe("parser", () => {
   });
 
   it("throw an error upon parsing error", () => {
-    expect(() => new Decoder().add('442["some","data"')).to.throwException(
-      /^invalid payload$/
-    );
+    const isInvalidPayload = (str) =>
+      expect(() => new Decoder().add(str)).to.throwException(
+        /^invalid payload$/
+      );
+
+    isInvalidPayload('442["some","data"');
+    isInvalidPayload('0/admin,"invalid"');
+    isInvalidPayload("1/admin,{}");
+    isInvalidPayload('2/admin,"invalid');
+    isInvalidPayload("2/admin,{}");
+
     expect(() => new Decoder().add("999")).to.throwException(
       /^unknown packet type 9$/
     );