fixop — Infrastructure Fix Operations

Detect and repair DNS, firewall, containers, TLS, systemd issues on local and remote servers. Zero external dependencies — uses only Python stdlib.

Install

pip install fixop

Usage as CLI

# Check remote server
fixop check --host myserver.com --user root

# Check specific categories
fixop check --host myserver.com --category dns,firewall,tls

# Auto-fix what can be fixed
fixop fix --host myserver.com --auto

# Interactive fix (confirm each)
fixop fix --host myserver.com --interactive

# Validate deploy artifacts locally
fixop validate deploy/

# Check TLS certificates
fixop check-tls app.example.com api.example.com

# Full diagnostic + fix pipeline
fixop doctor --host myserver.com --fix

# JSON output (for CI)
fixop check --host myserver.com --format json

Usage as Library

from fixop import HostContext, check_host_dns, check_ufw_forward_policy, fix_resolv_conf

ctx = HostContext(host="myserver.com", user="root")

# Detect issues
issues = check_host_dns(ctx)
for issue in issues:
    print(issue)  # [dns] Host DNS cannot resolve acme-v02.api.letsencrypt.org

# Run all checks at once
from fixop import check_all
issues = check_all(ctx, domains=["app.example.com"], containers=["traefik", "web"])

# Fix issues
result = fix_resolv_conf(ctx, nameservers=["8.8.8.8", "1.1.1.1"])
print(result)  # Set /etc/resolv.conf to 8.8.8.8, 1.1.1.1

# Classify runtime errors
from fixop import classify_error
issue = classify_error(exit_code=137, stderr="", cmd="podman run app")
print(issue)  # [container] Container killed (OOM or SIGKILL) (exit 137)

# Validate deploy files locally
from fixop import check_unresolved_vars, check_placeholders
issues = check_unresolved_vars(["deploy/traefik.yml", "deploy/web.container"])
issues += check_placeholders(["deploy/config.yml"])

Modules

Module	Purpose
ssh.py	SSH transport + connectivity checks
dns.py	DNS resolution + resolv.conf + systemd-resolved
firewall.py	UFW forward policy + iptables NAT masquerade
containers.py	Podman/Docker: health, running status, disk, memory
systemd.py	Unit management, graceful restart, daemon-reload
tls.py	Certificate validation (Let's Encrypt, self-signed)
ports.py	Port conflict detection + resolution
deploy.py	Deploy artifact validation (unresolved vars, placeholders)
health.py	HTTP/TCP endpoint health checks
classify.py	Runtime error classification (exit codes, stderr patterns)
cli.py	Standalone CLI

Key Design Principles

• Zero dependencies — stdlib only (subprocess, socket, ssl, pathlib, re, json)
• SSH via subprocess — uses the ssh command, not paramiko (optional extra)
• Taskfile-agnostic — operates on infrastructure primitives, not Taskfile.yml format
• Dispatch tables — uses data-driven classification instead of if/elif chains

License

Apache License 2.0 - see LICENSE for details.

Author

Created by Tom Sapletta - tom@sapletta.com