Add extra_hosts settings field for resolving internal hostnames#55
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Add extra_hosts settings field for resolving internal hostnames#55
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Maps hostname → IP in settings.json (user/project/local layers, merged with higher precedence winning). The mitmproxy addon writes entries to the shared mitmproxy-config volume, and wg-client appends them to /etc/hosts inside a sentinel block at startup; the agent inherits the file via network_mode: service:wg-client. Resolves #54. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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| lines.append(f"{address}\t{name}") | ||
| with open(EXTRA_HOSTS_PATH, "w") as f: | ||
| if lines: | ||
| f.write("\n".join(lines) + "\n") |
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Pull request overview
Adds support for resolving internal (non-public-DNS) hostnames inside the Sandcat sandbox by introducing an extra_hosts settings field that is merged across settings layers and applied at runtime via /etc/hosts.
Changes:
- Add
extra_hoststo settings merge semantics and document it in the root README. - Extend the mitmproxy addon to validate and write
extra_hostsmappings into the sharedmitmproxy-configvolume. - Update
wg-clientinit to append the generated mappings into/etc/hosts, and add unit tests covering merge/validation/output format.
Reviewed changes
Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.
| File | Description |
|---|---|
| README.md | Documents extra_hosts merge rules and how internal hostname resolution works end-to-end. |
| cli/test/mitmproxy/test_mitmproxy_addon.py | Adds tests for extra_hosts merging, validation, and file output format. |
| cli/templates/devcontainer/sandcat/scripts/wg-client-init.sh | Appends shared-volume extra_hosts content into /etc/hosts inside a sentinel block. |
| cli/templates/devcontainer/sandcat/scripts/mitmproxy_addon.py | Implements extra_hosts merge + validation, and writes an /etc/hosts-format file into the shared volume. |
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| if [ -f "$EXTRA_HOSTS_FILE" ]; then | ||
| sed -i '/^# sandcat extra_hosts BEGIN/,/^# sandcat extra_hosts END/d' /etc/hosts | ||
| if [ -s "$EXTRA_HOSTS_FILE" ]; then | ||
| { | ||
| echo "# sandcat extra_hosts BEGIN" | ||
| cat "$EXTRA_HOSTS_FILE" | ||
| echo "# sandcat extra_hosts END" | ||
| } >> /etc/hosts | ||
| fi |
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| self.env = merged["env"] | ||
| self._load_secrets(merged["secrets"]) | ||
| self._load_network_rules(merged["network"]) | ||
| self._write_placeholders_env() | ||
| self._write_extra_hosts(merged["extra_hosts"]) |
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Maps hostname → IP in settings.json (user/project/local layers, merged with higher precedence winning). The mitmproxy addon writes entries to the shared mitmproxy-config volume, and wg-client appends them to /etc/hosts inside a sentinel block at startup; the agent inherits the file via network_mode: service:wg-client. Resolves #54.