feat(vscode-desktop): pre-apply machine settings (#207)

registry/coder/modules/vscode-desktop/README.md

@@ -16,7 +16,7 @@ Uses the [Coder Remote VS Code Extension](https://github.com/coder/vscode-coder)
 module "vscode" {
   count    = data.coder_workspace.me.start_count
   source   = "registry.coder.com/coder/vscode-desktop/coder"
-  version  = "1.3.0"
+  version  = "1.4.0"
   agent_id = coder_agent.main.id
 }
 ```
@@ -29,7 +29,7 @@ module "vscode" {
 module "vscode" {
   count    = data.coder_workspace.me.start_count
   source   = "registry.coder.com/coder/vscode-desktop/coder"
-  version  = "1.3.0"
+  version  = "1.4.0"
   agent_id = coder_agent.main.id
   folder   = "/home/coder/project"
 }
@@ -43,7 +43,7 @@ Use `extensions` to install VS Code extension IDs before the first ordinary VS C
 module "vscode" {
   count    = data.coder_workspace.me.start_count
   source   = "registry.coder.com/coder/vscode-desktop/coder"
-  version  = "1.3.0"
+  version  = "1.4.0"
   agent_id = coder_agent.main.id
 
   extensions = [
@@ -55,4 +55,32 @@ module "vscode" {
 
 The installation blocks ordinary workspace login for up to 30 minutes so extensions are ready before VS Code Desktop connects. A download, extraction, validation, or extension installation failure remains visible in the Coder startup logs. Later workspace starts reuse the existing VS Code Server CLI and do not force extension updates.
 
-The workspace image must provide Bash, `base64`, `sed`, `tar`, and either `curl` or `wget`. The workspace also needs HTTPS egress to the VS Code update and artifact hosts. Extension availability and compatibility depend on the Visual Studio Marketplace; use `publisher.extension@version` to request a specific version.
+### Pre-apply machine settings
+
+Use `settings` to configure machine-level settings on the remote workspace host before the user connects. The module creates or merges these settings into `~/.vscode-server/data/Machine/settings.json`.
+
+```tf
+module "vscode" {
+  count    = data.coder_workspace.me.start_count
+  source   = "registry.coder.com/coder/vscode-desktop/coder"
+  version  = "1.4.0"
+  agent_id = coder_agent.main.id
+
+  extensions = [
+    "ms-python.python",
+    "esbenp.prettier-vscode@12.4.0",
+  ]
+
+  settings = {
+    "editor.fontSize"              = 14
+    "editor.formatOnSave"          = true
+    "workbench.colorCustomizations" = {
+      "editor.background" = "#1e1e1e"
+    }
+  }
+}
+```
+
+Existing settings in `settings.json` (including JSONC comments and trailing commas) are preserved, and user symlinks are respected and atomically updated.
+
+The workspace image must provide Bash, `base64`, `sed`, `tar`, and either `curl` or `wget`. Merging an existing settings file requires `python3`. Extension availability and compatibility depend on the Visual Studio Marketplace; use `publisher.extension@version` to request a specific version.

registry/coder/modules/vscode-desktop/main.test.ts

@@ -167,4 +167,44 @@ describe("vscode-desktop", async () => {
       await removeContainer(id);
     }
   });
+
+  it("does not create settings script with default inputs", async () => {
+    const state = await runTerraformApply(import.meta.dir, {
+      agent_id: "foo",
+    });
+    const settingsScripts = state.resources.filter(
+      (resource) =>
+        resource.type === "coder_script" &&
+        resource.name === "apply_settings",
+    );
+    expect(settingsScripts).toHaveLength(0);
+  });
+
+  it("creates login-blocking settings script when settings are configured", async () => {
+    const settings = {
+      "editor.fontSize": 14,
+      "editor.formatOnSave": true,
+    };
+    const state = await runTerraformApply(import.meta.dir, {
+      agent_id: "foo",
+      settings: JSON.stringify(settings),
+    });
+    const settingsScript = findResourceInstance(
+      state,
+      "coder_script",
+      "apply_settings",
+    );
+
+    expect(settingsScript.start_blocks_login).toBe(true);
+    expect(settingsScript.timeout).toBe(300);
+    expect(settingsScript.script).toContain(
+      Buffer.from(JSON.stringify(settings)).toString("base64"),
+    );
+    expect(settingsScript.script).toContain(
+      Buffer.from(
+        "$HOME/.vscode-server/data/Machine/settings.json",
+      ).toString("base64"),
+    );
+  });
 });
+

registry/coder/modules/vscode-desktop/main.tf

@@ -49,9 +49,40 @@ variable "extensions" {
   }
 }
 
+variable "settings" {
+  type        = any
+  description = "A map of settings to apply to VS Code Desktop's Machine settings. These settings are merged with any existing machine settings on startup."
+  default     = {}
+}
+
+variable "settings_file" {
+  type        = string
+  description = "Path to the settings.json file on the remote workspace host."
+  default     = "$HOME/.vscode-server/data/Machine/settings.json"
+}
+
 locals {
   module_directory = "$HOME/.coder-modules/coder/vscode-desktop"
   server_directory = "${local.module_directory}/server"
+  has_settings     = var.settings != null && var.settings != {}
+}
+
+resource "coder_script" "apply_settings" {
+  count              = local.has_settings ? 1 : 0
+  agent_id           = var.agent_id
+  display_name       = "VS Code Desktop Settings"
+  icon               = "/icon/code.svg"
+  run_on_start       = true
+  start_blocks_login = true
+  timeout            = 300
+  script = templatefile(
+    "${path.module}/scripts/apply-settings.sh.tftpl",
+    {
+      SETTINGS_B64      = base64encode(jsonencode(var.settings))
+      SETTINGS_FILE_B64 = base64encode(var.settings_file)
+      SCRIPTS_DIR       = "${path.module}/scripts"
+    },
+  )
 }
 
 module "vscode-desktop-core" {

registry/coder/modules/vscode-desktop/main.tftest.hcl

@@ -40,3 +40,37 @@ run "extensions_reject_empty_ids" {
     var.extensions,
   ]
 }
+
+run "settings_defaults_create_no_script" {
+  command = plan
+
+  assert {
+    condition     = length(coder_script.apply_settings) == 0
+    error_message = "Default inputs must not create a settings script."
+  }
+}
+
+run "settings_create_script" {
+  command = plan
+
+  variables {
+    settings = {
+      "editor.fontSize" = 14
+    }
+  }
+
+  assert {
+    condition     = length(coder_script.apply_settings) == 1
+    error_message = "Configured settings must create one settings script."
+  }
+
+  assert {
+    condition     = coder_script.apply_settings[0].start_blocks_login
+    error_message = "Settings script must block login by default."
+  }
+
+  assert {
+    condition     = coder_script.apply_settings[0].timeout == 300
+    error_message = "Settings script must have a finite timeout."
+  }
+}

registry/coder/modules/vscode-desktop/scripts/apply-settings.sh.tftpl

@@ -0,0 +1,78 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+expand_home() {
+  case "$1" in
+    '$HOME')
+      printf '%s\n' "$HOME"
+      ;;
+    '$HOME/'*)
+      printf '%s/%s\n' "$HOME" "$${1#\$HOME/}"
+      ;;
+    *)
+      printf '%s\n' "$1"
+      ;;
+  esac
+}
+
+decode_path() {
+  local encoded_path="$1"
+  local decoded_path
+
+  decoded_path="$(printf '%s' "$encoded_path" | base64 -d)"
+  expand_home "$decoded_path"
+}
+
+SETTINGS_FILE="$(decode_path '${SETTINGS_FILE_B64}')"
+
+if [ -z "$SETTINGS_FILE" ]; then
+  printf 'settings_file is required when settings are configured.\n' >&2
+  exit 1
+fi
+
+if [ -L "$SETTINGS_FILE" ]; then
+  if ! command -v python3 > /dev/null 2>&1; then
+    printf 'Resolving a symlinked IDE settings file requires python3.\n' >&2
+    exit 1
+  fi
+
+  SETTINGS_FILE="$(python3 - "$SETTINGS_FILE" << 'PY'
+${file("${SCRIPTS_DIR}/resolve-settings-path.py")}
+PY
+)"
+fi
+
+settings_directory="$(dirname "$SETTINGS_FILE")"
+mkdir -p "$settings_directory"
+
+desired_settings="$(mktemp "$settings_directory/.coder-settings.desired.XXXXXX")"
+merged_settings="$(mktemp "$settings_directory/.coder-settings.merged.XXXXXX")"
+trap 'rm -f "$desired_settings" "$merged_settings"' EXIT
+
+printf '%s' '${SETTINGS_B64}' | base64 -d > "$desired_settings"
+chmod 600 "$desired_settings"
+
+if [ ! -e "$SETTINGS_FILE" ]; then
+  mv "$desired_settings" "$SETTINGS_FILE"
+  printf 'Created IDE settings: %s\n' "$SETTINGS_FILE"
+  exit 0
+fi
+
+if [ ! -f "$SETTINGS_FILE" ]; then
+  printf 'IDE settings path is not a regular file: %s\n' "$SETTINGS_FILE" >&2
+  exit 1
+fi
+
+if ! command -v python3 > /dev/null 2>&1; then
+  printf 'Merging an existing IDE settings file requires python3.\n' >&2
+  exit 1
+fi
+
+python3 - "$SETTINGS_FILE" "$desired_settings" "$merged_settings" << 'PY'
+${file("${SCRIPTS_DIR}/merge-settings.py")}
+PY
+
+chmod 600 "$merged_settings"
+mv "$merged_settings" "$SETTINGS_FILE"
+printf 'Merged IDE settings: %s\n' "$SETTINGS_FILE"

registry/coder/modules/vscode-desktop/scripts/merge-settings.py

@@ -0,0 +1,119 @@
+import json
+import sys
+
+
+def strip_jsonc_comments(source):
+    result = []
+    index = 0
+    in_string = False
+    escaped = False
+
+    while index < len(source):
+        character = source[index]
+
+        if in_string:
+            result.append(character)
+            if escaped:
+                escaped = False
+            elif character == "\\":
+                escaped = True
+            elif character == '"':
+                in_string = False
+            index += 1
+            continue
+
+        if character == '"':
+            in_string = True
+            result.append(character)
+            index += 1
+            continue
+
+        if character == "/" and index + 1 < len(source):
+            next_character = source[index + 1]
+            if next_character == "/":
+                index += 2
+                while index < len(source) and source[index] not in "\r\n":
+                    index += 1
+                continue
+            if next_character == "*":
+                result.append(" ")
+                index += 2
+                while index + 1 < len(source):
+                    if source[index : index + 2] == "*/":
+                        index += 2
+                        break
+                    if source[index] in "\r\n":
+                        result.append(source[index])
+                    index += 1
+                else:
+                    raise ValueError("unterminated block comment in IDE settings")
+                continue
+
+        result.append(character)
+        index += 1
+
+    return "".join(result)
+
+
+def strip_trailing_commas(source):
+    result = []
+    index = 0
+    in_string = False
+    escaped = False
+
+    while index < len(source):
+        character = source[index]
+
+        if in_string:
+            result.append(character)
+            if escaped:
+                escaped = False
+            elif character == "\\":
+                escaped = True
+            elif character == '"':
+                in_string = False
+            index += 1
+            continue
+
+        if character == '"':
+            in_string = True
+        elif character == ",":
+            lookahead = index + 1
+            while lookahead < len(source) and source[lookahead].isspace():
+                lookahead += 1
+            if lookahead < len(source) and source[lookahead] in "}]":
+                index += 1
+                continue
+
+        result.append(character)
+        index += 1
+
+    return "".join(result)
+
+
+def load_jsonc(path):
+    with open(path, encoding="utf-8-sig") as source_file:
+        source = source_file.read()
+    return json.loads(strip_trailing_commas(strip_jsonc_comments(source)))
+
+
+def merge(existing, configured):
+    result = dict(existing)
+    for key, value in configured.items():
+        if isinstance(result.get(key), dict) and isinstance(value, dict):
+            result[key] = merge(result[key], value)
+        else:
+            result[key] = value
+    return result
+
+
+existing = load_jsonc(sys.argv[1])
+with open(sys.argv[2], encoding="utf-8") as configured_file:
+    configured = json.load(configured_file)
+
+if not isinstance(existing, dict):
+    raise ValueError("the existing IDE settings file must contain a JSON object")
+
+with open(sys.argv[3], "w", encoding="utf-8") as merged_file:
+    json.dump(merge(existing, configured), merged_file, indent=2)
+    merged_file.write("\n")

registry/coder/modules/vscode-desktop/scripts/resolve-settings-path.py

@@ -0,0 +1,9 @@
+from pathlib import Path
+import sys
+
+
+try:
+    print(Path(sys.argv[1]).resolve(strict=True))
+except (OSError, RuntimeError) as error:
+    print(f"Cannot resolve IDE settings symlink: {error}", file=sys.stderr)
+    raise SystemExit(1)