Fixed parsing messages with no headers (#14)

Author: zefir-git

src/Component.ts

@@ -22,10 +22,11 @@ export class Component implements Part {
      * @param data Component byte representation to parse
      */
     public static parse(data: Uint8Array): Component {
-        const headersEndIndex = Multipart.findSequenceIndex(data, Multipart.combineArrays([Multipart.CRLF, Multipart.CRLF]));
+        const hasHeaders = Multipart.findSequenceIndex(data, Multipart.CRLF) !== 0;
+        const headersEndIndex = hasHeaders ? Multipart.findSequenceIndex(data, Multipart.combineArrays([Multipart.CRLF, Multipart.CRLF])) + 2 : 0;
 
         const headersBuffer = data.slice(0, headersEndIndex);
-        const body = data.slice(headersEndIndex + 4);
+        const body = data.slice(headersEndIndex + 2);
 
         const headersString = new TextDecoder().decode(headersBuffer);
         const headers = new Headers();

test/Component.test.js

@@ -1,5 +1,5 @@
 import {expect} from "chai";
-import {Component} from "../dist/index.js";
+import {Multipart, Component} from "../dist/index.js";
 
 describe("Component", () => {
 
@@ -35,7 +35,7 @@ describe("Component", () => {
         it("should parse headers and body correctly from Uint8Array", () => {
             const headers = "Content-Type: text/plain\r\nContent-Length: 5\r\n\r\n";
             const body = new Uint8Array([1, 2, 3, 4, 5]);
-            const data = new Uint8Array([...headers.split("").map(c => c.charCodeAt(0)), ...body]);
+            const data = Multipart.combineArrays([new TextEncoder().encode(headers), body]);
 
             const component = Component.parse(data);
 
@@ -45,8 +45,8 @@ describe("Component", () => {
             expect(component.body).to.deep.equal(body);
         });
 
-        it("should handle missing headers and body", () => {
-            const data = new Uint8Array([0x0D, 0x0A, 0x0D, 0x0A]);
+        it("should handle missing headers and empty body", () => {
+            const data = new Uint8Array([0x0D, 0x0A]);
 
             const component = Component.parse(data);
 
@@ -57,14 +57,25 @@ describe("Component", () => {
 
         it("should handle headers with no body", () => {
             const headers = "Content-Type: text/plain\r\n\r\n";
-            const data = new Uint8Array([...headers.split("").map(c => c.charCodeAt(0))]);
+            const data = new TextEncoder().encode(headers);
 
             const component = Component.parse(data);
 
             expect(component.headers.get("Content-Type")).to.equal("text/plain");
 
             expect(component.body).to.deep.equal(new Uint8Array(0));
         });
+
+        it("should handle body with no headers", () => {
+            const body = "\r\nGoal: No headers!\r\n\r\nReally none.\r\n";
+            const data = new TextEncoder().encode(body);
+
+            const component = Component.parse(data);
+
+            expect(component.headers).to.be.empty;
+
+            expect(new TextDecoder().decode(component.body)).to.equal("Goal: No headers!\r\n\r\nReally none.\r\n");
+        });
     });
 
     describe("#bytes", () => {

test/Multipart.test.js

@@ -41,6 +41,51 @@ describe("Multipart", function () {
 
             expect(parsedMultipart).to.be.an.instanceof(Multipart);
             expect(parsedMultipart.parts.length).to.equal(2);
+            const part1 = parsedMultipart.parts[0];
+            expect(part1.headers.get("x-foo")).to.equal("bar");
+            expect(part1.body).to.deep.equal(component1.body);
+            const part2 = parsedMultipart.parts[1];
+            expect(part2.headers.get("content-type")).to.equal("text/plain");
+            expect(part2.body).to.deep.equal(component2.body);
+        });
+
+        it("should parse Multipart data from RFC 2046 5.1.1 example body", function () {
+            const string =
+                'From: Nathaniel Borenstein <[email protected]>\r\n' +
+                'To: Ned Freed <[email protected]>\r\n' +
+                'Date: Sun, 21 Mar 1993 23:56:48 -0800 (PST)\r\n' +
+                'Subject: Sample message\r\n' +
+                'MIME-Version: 1.0\r\n' +
+                'Content-type: multipart/mixed; boundary="simple boundary"\r\n' +
+                '\r\n' +
+                'This is the preamble.  It is to be ignored, though it\n' +
+                'is a handy place for composition agents to include an\r\n' +
+                'explanatory note to non-MIME conformant readers.\n' +
+                '\r\n' +
+                '--simple boundary\r\n' +
+                '\r\n' +
+                'This is implicitly typed plain US-ASCII text.\r\n' +
+                'It does NOT end with a linebreak.\r\n' +
+                '--simple boundary\r\n' +
+                'Content-type: text/plain; charset=us-ascii\r\n' +
+                '\r\n' +
+                'This is explicitly typed plain US-ASCII text.\r\n' +
+                'It DOES end with a linebreak.\r\n' +
+                '\r\n' +
+                '--simple boundary--\r\n' +
+                '\r\n' +
+                'This is the epilogue.  It is also to be ignored.';
+
+            const bytes = new TextEncoder().encode(string);
+            const parsedMultipart = Multipart.parse(bytes);
+
+            expect(parsedMultipart).to.be.an.instanceof(Multipart);
+            expect(parsedMultipart.parts.length).to.equal(2);
+            const part1 = parsedMultipart.parts[0];
+            expect(new TextDecoder().decode(part1.body)).to.equal("This is implicitly typed plain US-ASCII text.\r\nIt does NOT end with a linebreak.");
+            const part2 = parsedMultipart.parts[1];
+            expect(part2.headers.get("content-type")).to.equal("text/plain; charset=us-ascii");
+            expect(new TextDecoder().decode(part2.body)).to.equal("This is explicitly typed plain US-ASCII text.\r\nIt DOES end with a linebreak.\r\n");
         });
 
         it("should handle nested multiparts", function () {