Add `DEBUG_REMOTE_COMMANDS` flag and improve `code` remote command

CHANGELOG.md

@@ -10,6 +10,7 @@
 ### Changes
 - Proxy hop field now actually lists all known configs to pick from, instead of "TO DO" (#290)
 - Remote `code` command (#267) now prompts to create an empty file for non-existing path
+- Remote `code` command (#267) now displays a help message when not providing arguments
 
 ### Development changes
 - Webpack setup has been improved quite a bit, mostly to clean up long ugly paths and make builds deterministic:

src/config.ts

@@ -382,9 +382,11 @@ function parseFlagList(list: string[] | undefined, origin: string): Record<strin
   REMOTE_COMMANDS (boolean) (default=false)
     - Enables automatically launching a background command terminal during connection setup
     - Enables attempting to inject a file to be sourced by the remote shells (which adds the `code` alias)
+  DEBUG_REMOTE_COMMANDS (boolean) (default=false)
+    - Enables debug logging for the remote command terminal (thus useless if REMOTE_COMMANDS isn't true)
 */
 export type FlagValue = string | boolean | null;
-export type FlagCombo = [value: FlagValue, origin: string];
+export type FlagCombo<V extends FlagValue = FlagValue> = [value: V, origin: string];
 export const DEFAULT_FLAGS: string[] = [];
 let cachedFlags: Record<string, FlagCombo> = {};
 function calculateFlags(): Record<string, FlagCombo> {
@@ -456,12 +458,12 @@ export function getFlag(target: string, flags?: string[]): FlagCombo | undefined
  * @param flags An optional array of flags to check before the global ones
  * @returns The matching FlagCombo or `[missingValue, 'missing']` instead
  */
-export function getFlagBoolean(target: string, missingValue: boolean, flags?: string[]): FlagCombo {
+export function getFlagBoolean(target: string, missingValue: boolean, flags?: string[]): FlagCombo<boolean> {
   const combo = getFlag(target, flags);
   if (!combo) return [missingValue, 'missing'];
   const [value, reason] = combo;
   if (value == null) return [true, reason];
-  if (typeof value === 'boolean') return combo;
+  if (typeof value === 'boolean') return [value, reason];
   const lower = value.toLowerCase();
   if (lower === 'true' || lower === 't' || lower === 'yes' || lower === 'y') return [true, reason];
   if (lower === 'false' || lower === 'f' || lower === 'no' || lower === 'n') return [false, reason];

src/connection.ts

@@ -37,7 +37,12 @@ if type code > /dev/null 2> /dev/null; then
     return 0;
 fi
 code() {
-    if [ ! -n "$KELVIN_SSHFS_CMD_PATH" ]; then
+    if [ "$#" -ne 1 ] || [ $1 = "help" ] || [ $1 = "--help" ] || [ $1 = "-h" ] || [ $1 = "-?" ]; then
+        echo "Usage:";
+        echo "  code <path_to_existing_file>    Will make VS Code open the file";
+        echo "  code <path_to_existing_folder>  Will make VS Code add the folder as an additional workspace folder";
+        echo "  code <path_to_nonexisting_file> Will prompt VS Code to create an empty file, then open it afterwards";
+    elif [ ! -n "$KELVIN_SSHFS_CMD_PATH" ]; then
         echo "Not running in a terminal spawned by SSH FS? Failed to sent!"
     elif [ -c "$KELVIN_SSHFS_CMD_PATH" ]; then
         echo "::sshfs:code:$(pwd):::$1" >> $KELVIN_SSHFS_CMD_PATH;
@@ -74,7 +79,7 @@ export class ConnectionManager {
     public getPendingConnections(): [string, FileSystemConfig | undefined][] {
         return Object.keys(this.pendingConnections).map(name => [name, this.pendingConnections[name][1]]);
     }
-    protected async _createCommandTerminal(client: Client, authority: string): Promise<string> {
+    protected async _createCommandTerminal(client: Client, authority: string, debugLogging: boolean): Promise<string> {
         const logging = Logging.scope(`CmdTerm(${authority})`);
         const shell = await toPromise<ClientChannel>(cb => client.shell({}, cb));
         shell.write('echo ::sshfs:TTY:$(tty)\n');
@@ -83,7 +88,7 @@ export class ConnectionManager {
             shell.stdout.once('error', rejectPath);
             shell.once('close', () => rejectPath());
             rl.on('line', async line => {
-                // logging.debug('<< ' + line);
+                if (debugLogging) logging.debug('<< ' + line);
                 const [, prefix, cmd, args] = line.match(/(.*?)::sshfs:(\w+):(.*)$/) || [];
                 if (!cmd || prefix.endsWith('echo ')) return;
                 switch (cmd) {
@@ -170,8 +175,10 @@ export class ConnectionManager {
         // Set up stuff for receiving remote commands
         const [flagRCV, flagRCR] = getFlagBoolean('REMOTE_COMMANDS', false, actualConfig.flags);
         if (flagRCV) {
-            logging.info(`Flag REMOTE_COMMANDS provided in '${flagRCR}', setting up command terminal`);
-            const cmdPath = await this._createCommandTerminal(client, name);
+            const [flagRCDV, flagRCDR] = getFlagBoolean('DEBUG_REMOTE_COMMANDS', false, actualConfig.flags);
+            const withDebugStr = flagRCDV ? ` with debug logging enabled by '${flagRCDR}'` : '';
+            logging.info(`Flag REMOTE_COMMANDS provided in '${flagRCR}', setting up command terminal${withDebugStr}`);
+            const cmdPath = await this._createCommandTerminal(client, name, flagRCDV);
             environment.push({ key: 'KELVIN_SSHFS_CMD_PATH', value: cmdPath });
             const sftp = await toPromise<SFTPWrapper>(cb => client.sftp(cb));
             await toPromise(cb => sftp.writeFile('/tmp/.Kelvin_sshfs', TMP_PROFILE_SCRIPT, { mode: 0o666 }, cb));