Added BIND_ADDRESS environment variable

Author: zonia3000

.env.example

@@ -1,4 +1,5 @@
 PORT=3000
+BIND_ADDRESS=0.0.0.0
 FRACTAL_SERVER_URL=http://localhost:8000
 VIZARR_STATIC_FILES_PATH=/path/to/vizarr/dist
 BASE_PATH=/vizarr

CHANGELOG.md

@@ -1,5 +1,9 @@
 Note: Numbers like (#123) point to closed Pull Requests on the fractal-vizarr-viewer repository.
 
+# Unreleased
+
+* Added `BIND_ADDRESS` environment variable, defaulting to `0.0.0.0` for IPv4 binding (\#64);
+
 # 0.3.2
 
 * Updated vizarr git commit references to include labels feature;

README.md

@@ -64,6 +64,7 @@ To start the application installed in this way see the section [Run fractal-viza
 ## Environment variables
 
 * `PORT`: the port where fractal-vizarr-viewer app is served;
+* `BIND_ADDRESS`: specifies the IP address for the server to bind to; use `0.0.0.0` (IPv4) or `::` (IPv6) to listen on all interfaces, `127.0.0.1` (IPv4) or `::1` (IPv6) for localhost only; the default value is `0.0.0.0`;
 * `FRACTAL_SERVER_URL`: the base URL of fractal-server;
 * `VIZARR_STATIC_FILES_PATH`: path to the files generated running `npm run build` in vizarr source folder;
 * `BASE_PATH`: base path of fractal-vizarr-viewer application;
@@ -84,6 +85,7 @@ You can create a script with the following content to run fractal-vizarr-viewer
 #!/bin/sh
 
 export PORT=3000
+export BIND_ADDRESS=0.0.0.0
 export FRACTAL_SERVER_URL=http://localhost:8000
 export VIZARR_STATIC_FILES_PATH=/path/to/vizarr/dist
 export AUTHORIZATION_SCHEME=fractal-server
@@ -145,6 +147,7 @@ After=syslog.target
 [Service]
 User=fractal
 Environment="PORT=3000"
+Environment="BIND_ADDRESS=0.0.0.0"
 Environment="FRACTAL_SERVER_URL=https://fractal-server.example.com/"
 Environment="VIZARR_STATIC_FILES_PATH=/path/to/vizarr/dist"
 Environment="BASE_PATH=/vizarr"

src/app.ts

@@ -33,7 +33,7 @@ app.use(`${config.basePath}alive`, async function (req, res) {
 app.use(`${config.basePath}`, express.static(config.vizarrStaticFilesPath));
 
 // Start server
-const server = app.listen(config.port, () => {
+const server = app.listen(config.port, config.bindAddress, () => {
   logger.info(
     "fractal-vizarr-viewer is listening at http://localhost:%d%s",
     config.port,

src/config.ts

@@ -24,6 +24,7 @@ function getRequiredEnv(envName: string) {
  */
 function loadConfig(): Config {
   const port = process.env.PORT ? parseInt(process.env.PORT) : 3000;
+  const bindAddress = process.env.BIND_ADDRESS || "0.0.0.0";
   const fractalServerUrl = getRequiredEnv("FRACTAL_SERVER_URL");
   const vizarrStaticFilesPath = getRequiredEnv("VIZARR_STATIC_FILES_PATH");
 
@@ -59,6 +60,8 @@ function loadConfig(): Config {
     basePath += "/";
   }
 
+  logger.debug("PORT: %s", port);
+  logger.debug("BIND_ADDRESS: %s", bindAddress);
   logger.debug("FRACTAL_SERVER_URL: %s", fractalServerUrl);
   logger.debug("BASE_PATH: %s", basePath);
   logger.debug("VIZARR_STATIC_FILES_PATH: %s", vizarrStaticFilesPath);
@@ -67,6 +70,7 @@ function loadConfig(): Config {
 
   return {
     port,
+    bindAddress,
     fractalServerUrl,
     basePath,
     vizarrStaticFilesPath,

src/types.ts

@@ -5,6 +5,7 @@ export type AuthorizationScheme =
 
 export type Config = {
   port: number;
+  bindAddress: string;
   fractalServerUrl: string;
   basePath: string;
   vizarrStaticFilesPath: string;