Add support to CODER_BINARY_DESTINATION environment variable

Author: EhabY

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+### Added
+
+- Support for `CODER_BINARY_DESTINATION` environment variable to set CLI download location (overridden by extension setting `coder.binaryDestination` if configured).
+
 ## [v1.11.0](https://github.com/coder/vscode-coder/releases/tag/v1.11.0) 2025-09-24
 
 ### Changed

package.json

@@ -56,7 +56,7 @@
 					"default": ""
 				},
 				"coder.binaryDestination": {
-					"markdownDescription": "The full path of the directory into which the Coder CLI will be downloaded. Defaults to the extension's global storage directory.",
+					"markdownDescription": "The full path of the directory into which the Coder CLI will be downloaded. Defaults to the value of `CODER_BINARY_DESTINATION` if not set, otherwise the extension's global storage directory.",
 					"type": "string",
 					"default": ""
 				},

src/core/pathResolver.test.ts

@@ -1,5 +1,5 @@
 import * as path from "path";
-import { describe, it, expect, beforeEach } from "vitest";
+import { describe, it, expect, beforeEach, vi } from "vitest";
 import { MockConfigurationProvider } from "../__mocks__/testHelpers";
 import { PathResolver } from "./pathResolver";
 
@@ -11,6 +11,7 @@ describe("PathResolver", () => {
 	let mockConfig: MockConfigurationProvider;
 
 	beforeEach(() => {
+		vi.unstubAllEnvs();
 		pathResolver = new PathResolver(basePath, codeLogPath);
 		mockConfig = new MockConfigurationProvider();
 	});
@@ -32,6 +33,7 @@ describe("PathResolver", () => {
 		});
 
 		it("should use default path when custom destination is empty or whitespace", () => {
+			vi.stubEnv("CODER_BINARY_DESTINATION", "   ");
 			mockConfig.set("coder.binaryDestination", "   ");
 			expect(pathResolver.getBinaryCachePath("deployment")).toBe(
 				path.join(basePath, "deployment", "bin"),
@@ -41,7 +43,28 @@ describe("PathResolver", () => {
 		it("should normalize custom paths", () => {
 			mockConfig.set("coder.binaryDestination", "/custom/../binary/./path");
 			expect(pathResolver.getBinaryCachePath("deployment")).toBe(
-				path.normalize("/custom/../binary/./path"),
+				"/binary/path",
+			);
+		});
+
+		it("should use CODER_BINARY_DESTINATION environment variable with proper precedence", () => {
+			// Use the global storage when the environment variable and setting are unset/blank
+			vi.stubEnv("CODER_BINARY_DESTINATION", "");
+			mockConfig.set("coder.binaryDestination", "");
+			expect(pathResolver.getBinaryCachePath("deployment")).toBe(
+				path.join(basePath, "deployment", "bin"),
+			);
+
+			// Test environment variable takes precedence over global storage
+			vi.stubEnv("CODER_BINARY_DESTINATION", "   /env/binary/path   ");
+			expect(pathResolver.getBinaryCachePath("deployment")).toBe(
+				"/env/binary/path",
+			);
+
+			// Test setting takes precedence over environment variable
+			mockConfig.set("coder.binaryDestination", "  /setting/path  ");
+			expect(pathResolver.getBinaryCachePath("deployment")).toBe(
+				"/setting/path",
 			);
 		});
 	});

src/core/pathResolver.ts

@@ -28,11 +28,14 @@ export class PathResolver {
 	 * The caller must ensure this directory exists before use.
 	 */
 	public getBinaryCachePath(label: string): string {
-		const configPath = vscode.workspace
+		const settingPath = vscode.workspace
 			.getConfiguration()
-			.get<string>("coder.binaryDestination");
-		return configPath && configPath.trim().length > 0
-			? path.normalize(configPath)
+			.get<string>("coder.binaryDestination")
+			?.trim();
+		const binaryPath =
+			settingPath || process.env.CODER_BINARY_DESTINATION?.trim();
+		return binaryPath
+			? path.normalize(binaryPath)
 			: path.join(this.getGlobalConfigDir(label), "bin");
 	}