Merge pull request #133 from pulsar-edit/deedeeg/download/refactor

DeeDeeG's February 2024 refactor of the Download microservice (complementary to PR 132)
pulsar-edit · Feb 3, 2024 · 5a86240 · 5a86240
2 parents a12f06f + 2dea642
commit 5a86240
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Showing 2 changed files with 83 additions and 58 deletions.
diff --git a/microservices/download/index.js b/microservices/download/index.js
@@ -3,6 +3,16 @@ const utils = require("./utils.js");
 const port = parseInt(process.env.PORT) || 8080;
 
 const server = http.createServer(async (req, res) => {
+  if (typeof req?.url !== "string"){
+    // Not sure if this error condition is even possible, but handling it anyway
+    await utils.displayError(req, res, {
+      code: 500,
+      msg: "Internal Server Error: Misformed URL"
+    });
+    console.log("Download Returned 500 due to the requested URL not being received as a string internally");
+    return;
+  }
+
   // Since req.url is our URL plus query params, lets split them first.
   const url = req.url.split("?");
   const path = url[0];
@@ -11,21 +21,41 @@ const server = http.createServer(async (req, res) => {
   // Set our Request Route
   if (path === "/" && req.method === "GET") {
 
-    let params = {
+    if (typeof queryParams !== "string"){
+      await utils.displayError(req, res, {
+        code: 400,
+        msg: "Missing Query Parameters"
+      });
+      console.log("Download Returned 400 due to the requested URL having no query parameters");
+      return;
+    }
+
+    if (queryParams.length > 100){
+      // Longest valid combo is 36 characters ("os=silicon_mac&type=mac_zip_blockmap"),
+      // But leaving extra room to update the parameters in the future.
+      await utils.displayError(req, res, {
+        code: 414,
+        msg: "Requested Parameters are Too Long"
+      });
+      console.log("Download Returned 414 due to the provided parameters being too long");
+      return;
+    }
+
+    let validatedParams = {
       os: utils.query_os(queryParams),
       type: utils.query_type(queryParams)
     };
 
-    if (!params.os || !params.type) {
+    if (!validatedParams.os || !validatedParams.type) {
       await utils.displayError(req, res, {
-        code: 503,
-        msg: "Missing Required Download Parameters"
+        code: 400,
+        msg: "Required Download Parameters Missing or Invalid"
       });
-      console.log("Download Returned 503 due to missing os or type");
+      console.log("Download Returned 400 due to missing or invalid os or type");
       return;
     }
 
-    let redirLink = await utils.findLink(params.os, params.type);
+    let redirLink = await utils.findLink(validatedParams.os, validatedParams.type);
 
     if (!redirLink.ok) {
       await utils.displayError(req, res, redirLink);
@@ -37,7 +67,7 @@ const server = http.createServer(async (req, res) => {
       Location: redirLink.content
     }).end();
 
-    console.log(`Download Returned: OS: ${params.os} - TYPE: ${params.type} - URL: ${redirLink.content}`);
+    console.log(`Download Returned: OS: ${validatedParams.os} - TYPE: ${validatedParams.type} - URL: ${redirLink.content}`);
 
 
   } else {

diff --git a/microservices/download/utils.js b/microservices/download/utils.js
@@ -2,29 +2,12 @@ const https = require("node:https");
 const bins = require("./bins.js");
 let TOKEN = process.env.GH_TOKEN_DOWNLOAD_MICROSERVICE;
 
-const VALID_OS = [ "linux", "arm_linux", "silicon_mac", "intel_mac", "windows" ];
-const VALID_TYPE = [
-  "linux_appimage",
-  "linux_tar",
-  "linux_rpm",
-  "linux_deb",
-  "windows_setup",
-  "windows_portable",
-  "windows_blockmap",
-  "mac_zip",
-  "mac_zip_blockmap",
-  "mac_dmg",
-  "mac_dmg_blockmap"
-];
-
 // Environment Variables Check
 
 if (typeof TOKEN === "undefined") {
-  if (process.env.PULSAR_STATUS === "dev") {
-    // We are in dev mode, assign dev values
-    TOKEN = "123456";
-  } else {
-    // We are not in dev mode. Our secrets are gone and the application will fail to work
+  if (process.env.PULSAR_STATUS !== "dev") {
+    // We are not in dev mode. Our auth token is gone, and the application may fail to work
+    // due to rate limiting by GitHub for unauthenticated API requests.
     console.log("Missing Required Environment Variable: 'GH_TOKEN_DOWNLOAD_MICROSERVICE'!");
     process.exit(1);
   }
@@ -43,6 +26,12 @@ function doRequest() {
     }
   };
 
+  if (process.env.PULSAR_STATUS === "dev") {
+    // We don't expect to be authed in dev mode.
+    // Fetching releases from GitHub without authentication is fine in dev mode.
+    delete options.headers['Authorization'];
+  }
+
   return new Promise((resolve, reject) => {
     let data = '';
 
@@ -65,52 +54,58 @@ function doRequest() {
   });
 };
 
-function query_os(param) {
-  let raw = param; // The query string. From the URL string split by `?`
-  let prov = undefined;
-
-  if (typeof raw !== "string") {
+function query_os(queryString) {
+  if (typeof queryString !== "string") {
     return false;
   }
 
-  let full = raw.split("&");
+  const allParams = queryString.split("&");
+  const valid = [ "linux", "arm_linux", "silicon_mac", "intel_mac", "windows" ];
 
-  for (const param of full) {
+  for (const param of allParams) {
     if (param.startsWith("os=")) {
-      prov = param.split("=")[1];
-      break;
+      // Returning a result based on the first "os=" param we encounter.
+      // Users should not provide the same param twice, that would be invalid.
+      const prov = param.split("=")[1];
+      return valid.includes(prov) ? prov : false;
     }
   }
 
-  if (prov === undefined) {
-    return false;
-  }
-
-  return VALID_OS.includes(prov) ? prov : false;
+  // No "os" query param was provided, return false
+  return false;
 }
 
-function query_type(param) {
-  let raw = param;
-  let prov = undefined;
-
-  if (typeof raw !== "string") {
+function query_type(queryString) {
+  if (typeof queryString !== "string") {
     return false;
   }
 
-  let full = raw.split("&");
-
-  for (const param of full) {
+  const allParams = queryString.split("&");
+  const valid = [
+    "linux_appimage",
+    "linux_tar",
+    "linux_rpm",
+    "linux_deb",
+    "windows_setup",
+    "windows_portable",
+    "windows_blockmap",
+    "mac_zip",
+    "mac_zip_blockmap",
+    "mac_dmg",
+    "mac_dmg_blockmap"
+  ];
+
+  for (const param of allParams) {
     if (param.startsWith("type=")) {
-      prov = param.split("=")[1];
-      break;
+      // Returning a result based on the first "type=" param we encounter.
+      // Users should not provide the same param twice, that would be invalid.
+      const prov = param.split("=")[1];
+      return valid.includes(prov) ? prov : false;
     }
   }
 
-  if (prov === undefined) {
-    return false;
-  }
-
-  return VALID_TYPE.includes(prov) ? prov : false;
+  // No "type" query param was provided, return false
+  return false;
 }
 
 async function displayError(req, res, errMsg) {
@@ -185,8 +180,8 @@ async function findLink(os, type) {
     console.log(err);
     return {
       ok: false,
-      code: 505,
-      msg: "Server Error"
+      code: 500,
+      msg: "Server Error While Finding Link"
     };
   }
 }