feat: install progress bar + fix docker group creation order

Two tangled changes to the install flow, batched because they're both
small and hit app.py:

1. Phase-based progress bar on /install/log. parse_install_progress()
   scans the archinstall log for ordered phase markers ("Wiping
   partitions", "Installing packages: ['base'", "Adding bootloader",
   "Installation completed without any errors", …) and exposes
   percent + user-facing phase label + status (running/done/error).
   Template wraps the raw log in a collapsed <details> so the default
   view stays calm; the meta-refresh stops once status is terminal.
   If archinstall changes its stdout wording the bar stalls on the
   last recognized phase — the install itself is unaffected.

2. Drop "docker" from the user's groups in creds and do the
   `gpasswd -a <user> docker` via custom_commands instead.
   archinstall creates users before pacstrapping the extras list, so
   the docker group doesn't exist at user-create time —
   caused the second real install to crash with
   `gpasswd: group 'docker' does not exist`. custom_commands runs
   at the very end, after docker is installed. Username is validated
   by USERNAME_RE so no shell injection.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

webinstaller/app.py

@@ -33,6 +33,46 @@ settings = {
 HOSTNAME_RE = re.compile(r"^[a-z0-9]([a-z0-9-]{0,61}[a-z0-9])?$")
 USERNAME_RE = re.compile(r"^[a-z_][a-z0-9_-]{0,31}$")
 
+# Ordered phase markers for the install progress bar. Each tuple is
+# (substring to search for in the archinstall log, progress percent when
+# reached, user-facing label). Pick the furthest phase whose marker is
+# present in the log. If archinstall changes its stdout wording the bar
+# stalls on the last recognized phase — the install itself keeps going.
+PROGRESS_PHASES = [
+    ("Wiping partitions",                          8,   "Preparing your disk"),
+    ("Creating partitions",                        12,  "Creating partitions"),
+    ("Starting installation",                      15,  "Starting installation"),
+    ("Waiting for",                                18,  "Syncing time and packages"),
+    ("Installing packages: ['base'",               25,  "Installing the base system (this takes a while)"),
+    ("Adding bootloader",                          65,  "Setting up boot"),
+    ("Installing packages: ['efibootmgr'",         70,  "Setting up boot"),
+    ("Installing packages: ['docker'",             80,  "Installing your apps"),
+    ("Enabling service",                           90,  "Turning on services"),
+    ("Updating /mnt/etc/fstab",                    95,  "Almost done"),
+    ("Installation completed without any errors", 100,  "Done!"),
+]
+
+PROGRESS_ERROR_MARKERS = ("Traceback (most recent call last)", "archinstall: error:")
+
+
+def parse_install_progress(log):
+    percent = 2
+    phase = "Starting up…"
+    for marker, pct, label in PROGRESS_PHASES:
+        if marker in log:
+            percent = pct
+            phase = label
+
+    if percent >= 100:
+        status = "done"
+    elif any(m in log for m in PROGRESS_ERROR_MARKERS):
+        status = "error"
+        phase = "Installation failed — open Show details below"
+    else:
+        status = "running"
+
+    return {"percent": percent, "phase": phase, "status": status}
+
 
 def validate_step1(form):
     errors = []
@@ -102,6 +142,11 @@ def build_archinstall_config(s):
         "packages": ["docker", "docker-compose", "vim", "git", "htop", "curl"],
         "profile": {"type": "server"},
         "services": ["docker"],
+        # Add user to the docker group post-install. We can't put "docker" in
+        # the user's `groups` at create-time because archinstall creates users
+        # before pacstrapping the extras, so the docker group doesn't exist
+        # yet. custom_commands runs at the very end.
+        "custom_commands": [f"gpasswd -a {s['username']} docker"],
         "network_config": {"type": "iso"},
         "ssh": True,
         "audio_config": None,
@@ -123,7 +168,7 @@ def build_archinstall_creds(s):
                 "username": s["username"],
                 "!password": s["password"],
                 "sudo": True,
-                "groups": ["docker"],
+                "groups": [],
             }
         ],
     }
@@ -216,8 +261,12 @@ def install_run():
 
 @app.route("/install/log")
 def install_log_view():
-    log = INSTALL_LOG.read_text() if INSTALL_LOG.exists() else "(waiting for install to start)\n"
-    return render_template("install/log.html", log=log)
+    log = INSTALL_LOG.read_text() if INSTALL_LOG.exists() else ""
+    return render_template(
+        "install/log.html",
+        log=log,
+        progress=parse_install_progress(log),
+    )
 
 
 if __name__ == "__main__":

webinstaller/static/style.css

@@ -337,6 +337,45 @@ select:focus {
   margin: 0;
 }
 
+.progress {
+  background: var(--bg-subtle);
+  border: 1px solid var(--border);
+  border-radius: 999px;
+  height: 12px;
+  overflow: hidden;
+  margin: 1.5rem 0 0.5rem;
+}
+.progress-bar {
+  height: 100%;
+  background: linear-gradient(
+    90deg,
+    var(--accent),
+    color-mix(in srgb, var(--accent) 55%, #fff)
+  );
+  transition: width 0.6s ease;
+  border-radius: 999px;
+}
+.progress-bar-error { background: var(--danger); }
+.progress-bar-done { background: var(--success); }
+.progress-phase {
+  margin: 0.3rem 0 1.5rem;
+  color: var(--fg-muted);
+  font-size: 0.95rem;
+}
+
+.log-details {
+  margin-top: 1.5rem;
+}
+.log-details summary {
+  cursor: pointer;
+  font-size: 0.9rem;
+  color: var(--fg-muted);
+  user-select: none;
+  padding: 0.25rem 0;
+}
+.log-details summary:hover { color: var(--fg); }
+.log-details[open] summary { margin-bottom: 0.6rem; }
+
 /* ── Footer ─────────────────────────────────────────────────── */
 
 .site-footer {

webinstaller/templates/install/log.html

@@ -1,12 +1,30 @@
 {% extends "base.html" %}
 
 {% block title %}Installing… · Furtka Installer{% endblock %}
-{% block head_extra %}<meta http-equiv="refresh" content="3">{% endblock %}
+{% block head_extra %}
+{% if progress.status == "running" %}<meta http-equiv="refresh" content="3">{% endif %}
+{% endblock %}
 {% block step_indicator %}<span class="step-indicator">Installing</span>{% endblock %}
 
 {% block content %}
+{% if progress.status == "done" %}
+<h1>Furtka is ready</h1>
+<p class="lede">Installation finished. Remove the USB / eject the installer image, then reboot.</p>
+{% elif progress.status == "error" %}
+<h1>Installation hit a snag</h1>
+<p class="lede">Something went wrong. Open the details below and share them so we can help.</p>
+{% else %}
 <h1>Installing Furtka</h1>
-<p class="lede">This page reloads every 3 seconds. Don't close it. Don't power off.</p>
+<p class="lede">This takes a few minutes. Don't close this page or power off the machine.</p>
+{% endif %}
 
-<pre class="log">{{ log }}</pre>
+<div class="progress" role="progressbar" aria-valuemin="0" aria-valuemax="100" aria-valuenow="{{ progress.percent }}">
+    <div class="progress-bar{% if progress.status == 'error' %} progress-bar-error{% endif %}{% if progress.status == 'done' %} progress-bar-done{% endif %}" style="width: {{ progress.percent }}%;"></div>
+</div>
+<p class="progress-phase">{{ progress.phase }} · {{ progress.percent }}%</p>
+
+<details class="log-details">
+    <summary>Show details</summary>
+    <pre class="log">{{ log or "(waiting for install to start)" }}</pre>
+</details>
 {% endblock %}