api-endpoint-permission-canonicalizer

You are an expert terminal agent. You MUST use the provided tools to complete tasks. Use the terminal tool to run shell commands, read_file to read files, write_file to write files, search_files to search, and patch to edit files. Do NOT write out solutions as text - execute them using the tools. Always start by exploring the environment with terminal commands.

# API Endpoint Permission Canonicalizer

Transform an API endpoint permission configuration into a canonical form following access control and endpoint hierarchy semantics with strict validation, hard cutoff parsing, and complex permission resolution algorithms.

## Task

Implement `/app/canonicalize.py` that reads `/app/input.txt` and writes the canonical permission configuration to `/app/output.txt`.

## Input Format

`/app/input.txt` contains three sections separated by empty lines:

1. **ENDPOINTS**: `path method role permission` (one endpoint per line)
   - Paths are URL paths
   - Methods: `GET`, `POST`, `PUT`, `DELETE`, `PATCH` (case-insensitive, normalized to uppercase)
   - Roles are alphanumeric strings with optional underscores and hyphens
   - Permissions: `ALLOW`, `DENY` (case-insensitive, normalized to uppercase)
   - **Malformed lines**: A line is malformed if wrong number of fields (must be exactly 4), path is empty after stripping, method is invalid, permission is invalid, or role is empty after stripping
   - **Hard cutoff**: When a malformed line is encountered, stop parsing immediately and ignore that line and all subsequent lines in the ENDPOINTS section
   - Empty line separates this section

2. **BASE/EXCLUDE**:
   - `base <path>` - base path prefix (all endpoints must start with this, exact prefix match required)
   - `exclude <role1> <role2> ...` - roles to exclude (optional, may be empty, case-sensitive matching)
   - If `base` is not specified, all paths are eligible
   - If `exclude` is not specified or empty, no roles are excluded

3. **PLAN**: `<path method>` (one endpoint per line)
   - Endpoints explicitly requested
   - Methods are case-insensitive (normalized to uppercase)
   - **Malformed lines in PLAN**: A line is malformed if wrong number of fields (must be exactly 2), path is empty after stripping, or method is invalid
   - **Hard cutoff in PLAN**: When a malformed line is encountered in PLAN, stop parsing immediately and ignore that line and all subsequent lines in the PLAN section
   - Endpoints in PLAN not in ENDPOINTS (after cutoff) are ignored
   - Empty PLAN means include all eligible endpoints (subject to base/exclude filters)
   - When PLAN is empty, excluded roles are filtered out (no inheritance exception applies)

## Path Variable Normalization

Path variables must be normalized for matching but preserved in output.

1. **Normalization for matching**: Replace all path variable patterns `{variable_name}` with `{var}` for comparison purposes. This allows matching paths with different variable names that represent the same position.

2. **Preservation in output**: The original variable name must be preserved in the output. If multiple endpoints have the same normalized path but different variable names, use the first encountered variable name (by input order).

3. **Variable name extraction**: Extract variable names using pattern: `{` followed by alphanumeric characters, underscores, and hyphens, followed by `}`. Invalid patterns (with spaces, commas, colons, etc.) are treated as literal text.

## Rules

1. **Include eligible endpoints**: All endpoints from ENDPOINTS (up to cutoff point) that:
   - Match paths starting with `base` (if specified) - exact prefix match required (path must start with base, not just contain it)
   - Are not for excluded roles (unless needed for parent path inheritance - see Rule 2; when PLAN is empty, excluded roles are always filtered out)
   - Are either in PLAN (after PLAN cutoff), OR are parent paths of endpoints in PLAN (for hierarchical permission inheritance), OR all eligible endpoints if PLAN is empty (with excluded roles filtered out)

2. **Parent Path Resolution**:
   - For each endpoint in PLAN (or all eligible if PLAN is empty):
     - Find all parent paths by checking if any path is a prefix of the endpoint (using normalized path comparison)
     - A path is a parent if its normalized form is a prefix of the endpoint's normalized form (afte
… (2079 more chars)

I'll start by exploring the environment to understand what we're working with.

terminal({"command": "ls -la /app/"})

read_file({"path": "/app/input.txt"})

{"output": "total 8\ndrwxr-xr-x 2 root root 4096 Mar  4 09:08 .\ndrwxr-xr-x 1 root root 4096 Apr 24 19:58 ..", "exit_code": 0, "error": null}

{"content": "", "total_lines": 0, "file_size": 0, "truncated": false, "is_binary": false, "is_image": false, "error": "File not found: /app/input.txt"}

Now I understand the task. I need to implement `/app/canonicalize.py` that processes an API endpoint permission configuration. Let me build this carefully.

write_file({"path": "/app/canonicalize.py", "content": "#!/usr/bin/env python3\n\"\"\"API Endpoint Permission Canonicalizer.\"\"\"\n\nimport re\nimport sys\n\n\nVALID_METHODS = {\"GET\", \"POST\", \"PUT\", \"DELETE\", \"PATCH\"}\nVALID_PERMISSIONS = {\"ALLOW\", \"DENY\"}\nVAR_PATTERN = re.compile(r'\\{[A-Za-z0-9_-]+\\}')\n\n\ndef normalize_path(path):\n    \"\"\"Replace all valid path variable patterns {vari…)

{"bytes_written": 13223, "dirs_created": true}

Let me re-read the requirements more carefully and rewrite the solution with a cleaner approach.

write_file({"path": "/app/canonicalize.py", "content": "#!/usr/bin/env python3\n\"\"\"API Endpoint Permission Canonicalizer.\n\nTransforms API endpoint permission configuration into canonical form\nfollowing access control and endpoint hierarchy semantics.\n\"\"\"\n\nimport re\n\n\nVALID_METHODS = {\"GET\", \"POST\", \"PUT\", \"DELETE\", \"PATCH\"}\nVALID_PERMISSIONS = {\"ALLOW\", \"DENY\"}\nVAR_PATTERN = re…)

{"bytes_written": 9512, "dirs_created": true}

Let me create some test cases to verify the implementation:

write_file({"path": "/app/input.txt", "content": "/api/users GET admin ALLOW\n/api/users POST admin ALLOW\n/api/users/{user_id} GET admin ALLOW\n/api/users/{user_id} DELETE admin DENY\n/api/posts GET viewer ALLOW\n/api/posts/{post_id} GET viewer ALLOW\n\nbase /api\nexclude viewer\n\n/api/users GET admin\n/api/users/{user_id} GET admin\n"})

{"bytes_written": 276, "dirs_created": true}

Let me create a more comprehensive test and refine the solution:

write_file({"content": "#!/usr/bin/env python3\n\"\"\"API Endpoint Permission Canonicalizer.\n\nTransforms API endpoint permission configuration into canonical form\nfollowing access control and endpoint hierarchy semantics.\n\"\"\"\n\nimport re\n\n\nVALID_METHODS = {\"GET\", \"POST\", \"PUT\", \"DELETE\", \"PATCH\"}\nVALID_PERMISSIONS = {\"ALLOW\", \"DENY\"}\nVAR_PATTERN = re.compile(r'\\{[A-Za-z0-9_-]+\\}'…)

{"bytes_written": 8707, "dirs_created": true}

Now let me test with various test cases:

write_file({"content": "/api/users GET admin ALLOW\n/api/users POST admin ALLOW\n/api/users/{user_id} GET admin ALLOW\n/api/users/{user_id} DELETE admin DENY\n/api/posts GET viewer ALLOW\n/api/posts/{post_id} GET viewer ALLOW\n\nbase /api\nexclude viewer\n\n/api/users GET admin\n/api/users/{user_id} GET admin\n", "path": "/app/input.txt"})

{"bytes_written": 276, "dirs_created": true}

{"output": "/api/users/{user_id} DELETE admin DENY$\n/api/users/{user_id} GET admin ALLOW$\n/api/users GET admin ALLOW$\n/api/users POST admin ALLOW$", "exit_code": 0, "error": null}

Let me trace through the logic more carefully with debug output:

terminal({"command": "cd /app && python3 -c \"\nimport re\n\nVALID_METHODS = {'GET', 'POST', 'PUT', 'DELETE', 'PATCH'}\nVALID_PERMISSIONS = {'ALLOW', 'DENY'}\nVAR_PATTERN = re.compile(r'\\{[A-Za-z0-9_-]+\\}')\n\ndef normalize_path(path):\n    return VAR_PATTERN.sub('{var}', path)\n\ndef is_parent_path(parent_norm, child_norm):\n    if parent_norm == child_norm:\n        return False\n    if not child_norm.…)

{"output": "plan_set: {('/api/users/{var}', 'GET'), ('/api/users', 'GET')}\nplan_paths: {'/api/users', '/api/users/{var}'}\nnorm_path_to_endpoints keys: ['/api/users', '/api/users/{var}', '/api/posts', '/api/posts/{var}']\n  /api/users is parent of /api/users/{var}\nparent_norm_paths: {'/api/users'}\n/api/users GET: norm=/api/users, in_plan=True, is_parent=True\n/api/users POST: norm=/api/users, in_plan=False, is_parent=True\n/api/users/{user_id} GET: norm=/api/users/{var}, in_plan=True, is_parent=False\n/api/users/{user_id} DELETE: norm=/api/users/{var}, in_plan=False, is_parent=False\n/api/posts GET: norm=/api/posts, in_plan=False, is_parent=False\n/api/posts/{post_id} GET: norm=/api/posts/{var}, in_plan=False, is_parent=False", "exit_code": 0, "error": null}

Wait, the output includes `/api/users/{user_id} DELETE` but my trace says it shouldn't be included. Let me re-check:

terminal({"command": "cd /app && python3 canonicalize.py && echo \"---OUTPUT---\" && cat output.txt && echo \"---END---\""})

{"output": "---OUTPUT---\n/api/users/{user_id} DELETE admin DENY\n/api/users/{user_id} GET admin ALLOW\n/api/users GET admin ALLOW\n/api/users POST admin ALLOW\n---END---", "exit_code": 0, "error": null}

Hmm, the DELETE endpoint is included but shouldn't be based on my trace. Let me debug further:

terminal({"command": "cd /app && python3 -c \"\n# Debug the actual code path\nimport canonicalize as c\n\nendpoints_raw = [\n    '/api/users GET admin ALLOW',\n    '/api/users POST admin ALLOW',\n    '/api/users/{user_id} GET admin ALLOW',\n    '/api/users/{user_id} DELETE admin DENY',\n    '/api/posts GET viewer ALLOW',\n    '/api/posts/{post_id} GET viewer ALLOW',\n]\nplan_raw = [\n    '/api/users GET ad…)

{"output": "endpoints: [('/api/users', 'GET', 'admin', 'ALLOW', 0), ('/api/users', 'POST', 'admin', 'ALLOW', 1), ('/api/users/{user_id}', 'GET', 'admin', 'ALLOW', 2), ('/api/users/{user_id}', 'DELETE', 'admin', 'DENY', 3), ('/api/posts', 'GET', 'viewer', 'ALLOW', 4), ('/api/posts/{post_id}', 'GET', 'viewer', 'ALLOW', 5)]\nbase_path: /api\nexcluded_roles: ['viewer']\nplan: []\nafter base filter: [('/api/users', 'GET', 'admin', 'ALLOW', 0), ('/api/users', 'POST', 'admin', 'ALLOW', 1), ('/api/users/{user_id}', 'GET', 'admin', 'ALLOW', 2), ('/api/users/{user_id}', 'DELETE', 'admin', 'DENY', 3), ('/api/posts', 'GET', 'viewer', 'ALLOW', 4), ('/api/posts/{post_id}', 'GET', 'viewer', 'ALLOW', 5)]\nplan_set: set()\nplan_paths: set()\nparent_norm_paths: set()\n/api/users GET admin: norm=/api/users, in_plan=False, is_parent=False, include=False, excluded=False\n/api/users POST admin: norm=/api/users, in_plan=False, is_parent=False, include=False, excluded=False\n/api/users/{user_id} GET admin: norm=/api/users/{var}, in_plan=False, is_parent=False, include=False, excluded=False\n/api/users/{user_id} DELETE admin: norm=/api/users/{var}, in_plan=False, is_parent=False, include=False, excluded=False\n/api/posts GET viewer: norm=/api/posts, in_plan=False, is_parent=False, include=False, excluded=True\n/api/posts/{post_id} GET viewer: norm=/api/posts/{var}, in_plan=False, is_parent=False, include=False, excluded=True", "exit_code": 0, "error": null}

The plan is empty! The issue is that the plan lines have 3 fields (`/api/users GET admin`) but should have 2. The input format for PLAN is `<path method>`, not `<path method role>`. Let me fix the test input:

write_file({"content": "/api/users GET admin ALLOW\n/api/users POST admin ALLOW\n/api/users/{user_id} GET admin ALLOW\n/api/users/{user_id} DELETE admin DENY\n/api/posts GET viewer ALLOW\n/api/posts/{post_id} GET viewer ALLOW\n\nbase /api\nexclude viewer\n\n/api/users GET\n/api/users/{user_id} GET\n", "path": "/app/input.txt"})

{"bytes_written": 264, "dirs_created": true}

{"output": "---OUTPUT---\n/api/users/{user_id} GET admin ALLOW\n/api/users GET admin ALLOW\n/api/users POST admin ALLOW\n---END---", "exit_code": 0, "error": null}

Now let me trace through the logic:
- `/api/users GET` is in plan → include `/api/users GET admin ALLOW` ✓
- `/api/users/{user_id} GET` is in plan → include `/api/users/{user_id} GET admin ALLOW` ✓
- `/api/users` is parent of `/api/users/{var}` → include all `/api/users` endpoints → `/api/users POST admin ALLOW` ✓
- `/api/users/{user_id} DELETE` is NOT in plan and `/api/users/{var}` is NOT a parent of anything → excluded ✓
- `viewer` endpoints are excluded ✓

Let me test more edge cases:

write_file({"content": "/api/users GET admin ALLOW\n/api/users POST admin ALLOW\n/api/users/{user_id} GET admin ALLOW\n/api/users/{user_id} DELETE admin DENY\n/api/posts GET viewer ALLOW\n/api/posts/{post_id} GET viewer ALLOW\n\nbase /api\nexclude viewer\n", "path": "/app/input.txt"})

{"bytes_written": 223, "dirs_created": true}

{"output": "---OUTPUT---\n/api/users/{user_id} DELETE admin DENY\n/api/users/{user_id} GET admin ALLOW\n/api/users GET admin ALLOW\n/api/users POST admin ALLOW\n---END---", "exit_code": 0, "error": null}

PLAN is empty, so all eligible endpoints are included (excluding viewer roles). Good. Now let me test hard cutoff:

write_file({"content": "/api/users GET admin ALLOW\n/api/users POST admin ALLOW\nBADLINE\n/api/users/{user_id} GET admin ALLOW\n\nbase /api\n\n/api/users GET\n", "path": "/app/input.txt"})

{"bytes_written": 127, "dirs_created": true}

{"output": "---OUTPUT---\n/api/users GET admin ALLOW\n---END---", "exit_code": 0, "error": null}

Hard cutoff works - BADLINE caused parsing to stop, so only the first 2 endpoints are valid, and only `/api/users GET` matches the plan.

Now let me test path variable normalization:

write_file({"content": "/api/users/{user_id} GET admin ALLOW\n/api/users/{uid} POST admin ALLOW\n/api/users/{user_id} DELETE admin DENY\n\nbase /api\n\n/api/users/{x} GET\n/api/users/{y} POST\n", "path": "/app/input.txt"})

{"bytes_written": 161, "dirs_created": true}

{"output": "---OUTPUT---\n/api/users/{user_id} GET admin ALLOW\n/api/users/{uid} POST admin ALLOW\n---END---", "exit_code": 0, "error": null}

Path variable normalization works - `{user_id}`, `{uid}`, `{x}`, `{y}` all normalize to `{var}`. The first encountered original path names are preserved in output.

Let me test the inheritance exception for excluded roles:

write_file({"content": "/api/users GET admin ALLOW\n/api/users POST admin ALLOW\n/api/users/{user_id} GET restricted ALLOW\n/api/users/{user_id} DELETE restricted DENY\n/api/users/{user_id}/posts GET restricted ALLOW\n\nbase /api\nexclude restricted\n\n/api/users/{user_id}/posts GET\n", "path": "/app/input.txt"})

{"bytes_written": 251, "dirs_created": true}

{"output": "---OUTPUT---\n/api/users/{user_id} DELETE restricted DENY\n/api/users/{user_id} GET restricted ALLOW\n/api/users GET admin ALLOW\n/api/users POST admin ALLOW\n---END---", "exit_code": 0, "error": null}

Let me trace through this:
- Plan: `/api/users/{user_id}/posts GET` → normalized: `/api/users/{var}/posts GET`
- Parent paths of `/api/users/{var}/posts`: `/api/users/{var}` and `/api/users`
- `/api/users/{var}` endpoints are all `restricted` (excluded) → inheritance exception applies
- `/api/users` endpoints are `admin` (not excluded) → included normally
- `/api/users/{var}/posts` is directly requested but only has `restricted` role → excluded (directly requested, no inheritance exception)

Wait, but `/api/users/{user_id}/posts GET restricted ALLOW` should be directly requested but the role is excluded. Since it's directly requested (not a parent), the inheritance exception doesn't apply. That's correct.

Now let me test with no base path:

write_file({"content": "/api/users GET admin ALLOW\n/api/users POST admin ALLOW\n/health GET viewer ALLOW\n\nexclude viewer\n\n/api/users GET\n", "path": "/app/input.txt"})

{"bytes_written": 112, "dirs_created": true}

{"output": "---OUTPUT---\n/api/users GET admin ALLOW\n---END---", "exit_code": 0, "error": null}