Add CONTRIBUTING.md and demo GIF to README

Author: kylecarbs

CONTRIBUTING.md

@@ -0,0 +1,46 @@
+# Contributing
+
+## Architecture
+
+Workspaces opened with Coder Remote have the following URI structure:
+
+```
+vscode://ssh-remote+coder-vscode--<username>--<workspace>/
+```
+
+The `ssh-remote` scheme is used by the [Remote - SSH](https://marketplace.visualstudio.com/items?itemName=ms-vscode-remote.remote-ssh) extension from Microsoft that connects to remote machines.
+
+Coder uses the `onResolveRemoteAuthority:ssh-remote` [extension activation event](https://code.visualstudio.com/api/references/activation-events) to activate the workspace when this scheme is used. On activation, we check if `vscode.workspace.workspaceFolders` contains the `coder-vscode--` prefix, and if so we delay activation to:
+
+1. Match the workspace owner and name from the URI scheme and validate it's accessible.
+2. Download the matching server binary to the client.
+3. Add an entry to the users SSH config for VS Code Remote to resolve `coder-vscode--*`.
+
+```
+Host coder-vscode--*
+	ProxyCommand "/tmp/coder" vscodessh --network-info-dir "/home/kyle/.config/Code/User/globalStorage/coder.coder-remote/net" --session-token-file "/home/kyle/.config/Code/User/globalStorage/coder.coder-remote/session_token" --url-file "/home/kyle/.config/Code/User/globalStorage/coder.coder-remote/url" %h
+	ConnectTimeout 0
+	StrictHostKeyChecking no
+	UserKnownHostsFile /dev/null
+	LogLevel ERROR
+```
+
+VS Code SSH uses the `ssh -D <port>` flag to start a SOCKS server on the specified port. This port is printed to the `Remote - SSH` log file in the VS Code Output panel in the format `-> socksPort <port> ->`. We use this port to find the SSH process ID that is being used by the remote session.
+
+The `vscodessh` subcommand on the `coder` binary periodically flushes it's network information to `network-info-dir + "/" + process.ppid`. SSH executes `ProxyCommand`, which means the `process.ppid` will always be the matching SSH command.
+
+Coder Remote periodically reads the `network-info-dir + "/" + matchingSSHPID` file to display network information.
+
+## Development
+
+1. Run `yarn watch` in the background.
+2. Compile the `coder` binary and place it in the equivalent of `os.tmpdir() + "/coder"`.
+
+   On Linux or Mac:
+
+   ```bash
+   # Inside https://github.com/coder/coder
+   $ go build -o /tmp/coder ./cmd/coder
+   ```
+
+3. Press `F5` or navigate to the "Run and Debug" tab of VS Code and click "Run Extension".

README.md

@@ -15,6 +15,8 @@ The Coder Remote VS Code extension lets you open
 - Works in air-gapped or restricted networks. Just connect to your Coder
   deployment!
 
+![demo.gif](./demo.gif)
+
 ## Getting Started
 
 Launch VS Code Quick Open (Ctrl+P), paste the following command, and press

demo.gif

@@ -5,7 +5,7 @@
   "description": "Open any workspace with a single click.",
   "repository": "https://github.com/coder/vscode-coder",
   "preview": true,
-  "version": "0.0.7",
+  "version": "0.0.8",
   "engines": {
     "vscode": "^1.73.0"
   },

package.json

@@ -384,13 +384,15 @@ export class Remote {
     const parsedConfig = SSHConfig.parse(sshConfigRaw)
     const computedHost = parsedConfig.compute(sshHost)
 
-    let binaryPath = await this.storage.fetchBinary()
+    let binaryPath: string | undefined
+    if (this.mode === vscode.ExtensionMode.Production) {
+      binaryPath = await this.storage.fetchBinary()
+    } else {
+      binaryPath = path.join(os.tmpdir(), "coder")
+    }
     if (!binaryPath) {
       throw new Error("Failed to fetch the Coder binary!")
     }
-    if (this.mode === vscode.ExtensionMode.Development) {
-      binaryPath = path.join(os.tmpdir(), "coder")
-    }
 
     parsedConfig.remove({ Host: computedHost.Host })
     const escape = (str: string): string => `"${str.replace(/"/g, '\\"')}"`