refactor: server environemntal variables

* Prefix each variable with REFINERY_
* If not public host is specified, allow all origings and compute the WebSocket
  address on the client from the origin.

3 files changed, 22 insertions, 17 deletions

diff --git a/subprojects/language-web/build.gradle.kts b/subprojects/language-web/build.gradle.kts
index 9f772d41..88dccdf3 100644
--- a/subprojects/language-web/build.gradle.kts
+++ b/subprojects/language-web/build.gradle.kts
@@ -64,8 +64,18 @@ tasks {
                 classpath(mainRuntimeClasspath)
                 mainClass.set(application.mainClass)
                 standardInput = System.`in`
-                environment("BASE_RESOURCE", webapp.singleFile)
+                environment("REFINERY_BASE_RESOURCE", webapp.singleFile)
                 group = "run"
                 description = "Start a Jetty web server serving the Xtext API and assets."
         }
+
+        register<JavaExec>("serveBackendOnly") {
+                val mainRuntimeClasspath = sourceSets.main.map { it.runtimeClasspath }
+                dependsOn(mainRuntimeClasspath)
+                classpath(mainRuntimeClasspath)
+                mainClass.set(application.mainClass)
+                standardInput = System.`in`
+                group = "run"
+                description = "Start a Jetty web server serving the Xtext API without assets."
+        }
 }
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/ServerLauncher.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/ServerLauncher.java
index 3e1d811b..d633b3fc 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/ServerLauncher.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/ServerLauncher.java
@@ -33,7 +33,7 @@ import java.util.EnumSet;
 import java.util.Set;
 
 public class ServerLauncher {
-        public static final String DEFAULT_LISTEN_ADDRESS = "localhost";
+        public static final String DEFAULT_LISTEN_HOST = "localhost";
 
         public static final int DEFAULT_LISTEN_PORT = 1312;
 
@@ -105,7 +105,7 @@ public class ServerLauncher {
 
         private Resource getBaseResource() {
                 var factory = ResourceFactory.of(server);
-                var baseResourceOverride = System.getenv("BASE_RESOURCE");
+                var baseResourceOverride = System.getenv("REFINERY_BASE_RESOURCE");
                 if (baseResourceOverride != null) {
                         // If a user override is provided, use it.
                         return factory.newResource(baseResourceOverride);
@@ -155,15 +155,15 @@ public class ServerLauncher {
         }
 
         private static String getListenAddress() {
-                var listenAddress = System.getenv("LISTEN_ADDRESS");
+                var listenAddress = System.getenv("REFINERY_LISTEN_HOST");
                 if (listenAddress == null) {
-                        return DEFAULT_LISTEN_ADDRESS;
+                        return DEFAULT_LISTEN_HOST;
                 }
                 return listenAddress;
         }
 
         private static int getListenPort() {
-                var portStr = System.getenv("LISTEN_PORT");
+                var portStr = System.getenv("REFINERY_LISTEN_PORT");
                 if (portStr != null) {
                         return Integer.parseInt(portStr);
                 }
@@ -177,7 +177,7 @@ public class ServerLauncher {
         }
 
         private static String getPublicHost() {
-                var publicHost = System.getenv("PUBLIC_HOST");
+                var publicHost = System.getenv("REFINERY_PUBLIC_HOST");
                 if (publicHost != null) {
                         return publicHost.toLowerCase();
                 }
@@ -185,7 +185,7 @@ public class ServerLauncher {
         }
 
         private static int getPublicPort() {
-                var portStr = System.getenv("PUBLIC_PORT");
+                var portStr = System.getenv("REFINERY_PUBLIC_PORT");
                 if (portStr != null) {
                         return Integer.parseInt(portStr);
                 }
@@ -193,7 +193,7 @@ public class ServerLauncher {
         }
 
         private static String[] getAllowedOrigins() {
-                var allowedOrigins = System.getenv("ALLOWED_ORIGINS");
+                var allowedOrigins = System.getenv("REFINERY_ALLOWED_ORIGINS");
                 if (allowedOrigins != null) {
                         return allowedOrigins.split(ALLOWED_ORIGINS_SEPARATOR);
                 }
@@ -222,12 +222,10 @@ public class ServerLauncher {
                 int port;
                 var publicHost = getPublicHost();
                 if (publicHost == null) {
-                        host = getListenAddress();
-                        port = getListenPort();
-                } else {
-                        host = publicHost;
-                        port = getPublicPort();
+                        return null;
                 }
+                host = publicHost;
+                port = getPublicPort();
                 var scheme = port == HTTPS_DEFAULT_PORT ? "wss" : "ws";
                 return String.format("%s://%s:%d/xtext-service", scheme, host, port);
         }
diff --git a/subprojects/language-web/src/main/java/tools/refinery/language/web/config/BackendConfigServlet.java b/subprojects/language-web/src/main/java/tools/refinery/language/web/config/BackendConfigServlet.java
index a2f04e34..7d0a5122 100644
--- a/subprojects/language-web/src/main/java/tools/refinery/language/web/config/BackendConfigServlet.java
+++ b/subprojects/language-web/src/main/java/tools/refinery/language/web/config/BackendConfigServlet.java
@@ -25,9 +25,6 @@ public class BackendConfigServlet extends HttpServlet {
         public void init(ServletConfig config) throws ServletException {
                 super.init(config);
                 var webSocketUrl = config.getInitParameter(WEBSOCKET_URL_INIT_PARAM);
-                if (webSocketUrl == null) {
-                        throw new IllegalArgumentException("Init parameter " + WEBSOCKET_URL_INIT_PARAM + " is mandatory");
-                }
                 var backendConfig = new BackendConfig(webSocketUrl);
                 var gson = new Gson();
                 serializedConfig = gson.toJson(backendConfig);