feat(server): allow environment label override

apps/server/src/environment/ServerEnvironmentLabel.test.ts

@@ -1,4 +1,5 @@
 import { afterEach, describe, expect, it } from "@effect/vitest";
+import * as ConfigProvider from "effect/ConfigProvider";
 import * as Effect from "effect/Effect";
 import * as FileSystem from "effect/FileSystem";
 import * as Layer from "effect/Layer";
@@ -55,12 +56,53 @@ const withHostPlatform = <ROut, E, RIn>(
     Layer.succeed(HostProcessPlatform, platform),
     Layer.succeed(HostProcessHostname, hostname),
   );
+const withEnvironmentLabel = <ROut, E, RIn>(
+  layer: Layer.Layer<ROut, E, RIn>,
+  platform: NodeJS.Platform,
+  hostname: string,
+  environmentLabel: string,
+) =>
+  Layer.merge(
+    withHostPlatform(layer, platform, hostname),
+    ConfigProvider.layer(
+      ConfigProvider.fromEnv({ env: { T3CODE_ENVIRONMENT_LABEL: environmentLabel } }),
+    ),
+  );
 
 afterEach(() => {
   runMock.mockReset();
 });
 
 describe("resolveServerEnvironmentLabel", () => {
+  it.effect("prefers and trims a configured environment label", () =>
+    Effect.gen(function* () {
+      const result = yield* ServerEnvironmentLabel.resolveServerEnvironmentLabel({
+        cwdBaseName: "t3code",
+      }).pipe(
+        Effect.provide(
+          withEnvironmentLabel(LinuxMachineInfoLayer, "linux", "buildbox", "  Build server  "),
+        ),
+      );
+
+      expect(result).toBe("Build server");
+      expect(runMock).not.toHaveBeenCalled();
+    }),
+  );
+
+  it.effect("ignores empty configured environment labels", () =>
+    Effect.gen(function* () {
+      for (const environmentLabel of ["", " \t "]) {
+        const result = yield* ServerEnvironmentLabel.resolveServerEnvironmentLabel({
+          cwdBaseName: "t3code",
+        }).pipe(
+          Effect.provide(withEnvironmentLabel(TestLayer, "win32", "macbook-pro", environmentLabel)),
+        );
+
+        expect(result).toBe("macbook-pro");
+      }
+    }),
+  );
+
   it.effect("uses hostname fallback regardless of launch mode", () =>
     Effect.gen(function* () {
       const result = yield* ServerEnvironmentLabel.resolveServerEnvironmentLabel({

apps/server/src/environment/ServerEnvironmentLabel.ts

@@ -1,4 +1,5 @@
 import { HostProcessHostname, HostProcessPlatform } from "@t3tools/shared/hostProcess";
+import * as Config from "effect/Config";
 import * as Effect from "effect/Effect";
 import * as FileSystem from "effect/FileSystem";
 import * as Option from "effect/Option";
@@ -182,6 +183,13 @@ const resolveFriendlyHostLabel = Effect.fn("resolveFriendlyHostLabel")(function*
 export const resolveServerEnvironmentLabel = Effect.fn("resolveServerEnvironmentLabel")(function* (
   input: ResolveServerEnvironmentLabelInput,
 ) {
+  const configuredLabel = normalizeLabel(
+    Option.getOrUndefined(yield* Config.String("T3CODE_ENVIRONMENT_LABEL").pipe(Config.option)),
+  );
+  if (configuredLabel) {
+    return configuredLabel;
+  }
+
   const friendlyHostLabel = yield* resolveFriendlyHostLabel();
   if (friendlyHostLabel) {
     return friendlyHostLabel;

docs/user/install.md

@@ -33,6 +33,15 @@ line to add. Set `T3CODE_CHANNEL=nightly` to install the nightly train, or
 | Move to the newest release                       | `t3 update`                                               |
 | Remove it again                                  | `t3 uninstall`                                            |
 
+Set `T3CODE_ENVIRONMENT_LABEL` in the server process environment to override the environment name
+shown to connected clients:
+
+```sh
+T3CODE_ENVIRONMENT_LABEL="Development VM" t3 serve
+```
+
+Empty or whitespace-only values use the normal automatically detected label.
+
 Run `t3 --help` for the full reference.
 
 To try T3 Code once without installing it, run `npx t3@latest` instead (needs