Agent host check: run every step, and say so

The check went to the host on stdin, and the first docker compose exec read
the rest of it: the memory and firewall checks never ran, and it passed.
It is now its own file, sent as an argument, and ends with "all checks
passed" only when every check has run. Tests fake the host with a docker
that reads stdin.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01J5Utyfzw7gF7UhjRDEtjTk

tests/deploy/test_agent_host.py

@@ -115,3 +115,72 @@ def test_the_firewall_lets_only_one_address_in_and_replaces_its_own_rule() -> No
     assert run.stdout.splitlines().index(rule) < run.stdout.splitlines().index(
         "-A DOCKER-USER -j RETURN"
     )
+
+
+SCRIPT = HOST.parents[1] / "scripts" / "agent-host.sh"
+
+
+def _fake_host(tmp_path: Path, *, memory_writable: bool) -> dict[str, str]:
+    """Commands standing in for the host's: ssh runs the command here, sudo
+    just runs it, and docker reads all of stdin, as docker compose exec does."""
+    bin_ = tmp_path / "bin"
+    bin_.mkdir()
+    stubs = {
+        "ssh": 'for last; do :; done; exec bash -c "$last"',
+        "sudo": 'exec "$@"',
+        "curl": "echo 200",
+        "iptables": "echo '-A DOCKER-USER -m comment --comment nisse-firewall -j DROP'",
+        "docker": (
+            "cat > /dev/null\n"
+            'case "$*" in\n'
+            '  *"ps --status running"*) echo abc123 ;;\n'
+            f'  *"/vault/memory/"*) exit {0 if memory_writable else 1} ;;\n'
+            "esac"
+        ),
+    }
+    for name, body in stubs.items():
+        path = bin_ / name
+        path.write_text(f"#!/usr/bin/env bash\n{body}\n")
+        path.chmod(0o755)
+    stack = tmp_path / "stack"
+    stack.mkdir()
+    return {"PATH": f"{bin_}:/usr/bin:/bin", "STACK": str(stack), "HOME": str(tmp_path)}
+
+
+def _check(env: dict[str, str]) -> subprocess.CompletedProcess[str]:
+    return subprocess.run(
+        ["bash", str(SCRIPT), "check"],
+        env=env,
+        capture_output=True,
+        text=True,
+        timeout=30,
+        check=False,
+    )
+
+
+def test_the_check_runs_every_step_even_though_docker_reads_stdin(
+    tmp_path: Path,
+) -> None:
+    # Fed to the host on stdin, the first docker compose exec swallowed the
+    # rest of the check, which then passed without the last two steps.
+    result = _check(_fake_host(tmp_path, memory_writable=False))
+    assert result.returncode == 0, result.stdout + result.stderr
+    assert result.stdout.splitlines() == [
+        "ok:   SilverBullet is running",
+        "ok:   it answers locally (200)",
+        "ok:   the operator's folders are writable",
+        "ok:   memory/ is read-only to SilverBullet",
+        "ok:   the firewall rule is in place",
+        "all checks passed",
+    ]
+
+
+def test_a_writable_memory_folder_fails_the_check(tmp_path: Path) -> None:
+    result = _check(_fake_host(tmp_path, memory_writable=True))
+    assert result.returncode == 1
+    assert (
+        "FAIL: memory/ is writable from SilverBullet, even as root in it"
+        in result.stdout
+    )
+    assert "ok:   the firewall rule is in place" in result.stdout  # still checked
+    assert "all checks passed" not in result.stdout