Github Checks (import) (#750)

vishalshenoy · web-flow · commit 09b797a4b336 · 2025-03-05T11:08:22.000-08:00
diff --git a/codegen-examples/examples/github_checks/README.md b/codegen-examples/examples/github_checks/README.md
@@ -0,0 +1,106 @@
+# Github Checks
+
+This application is a GitHub integration that analyzes import cycles in Python codebases. It automatically runs when a pull request is labeled and checks for potentially problematic import patterns in the modified codebase.
+
+## Features
+
+- Analyzes import relationships in Python codebases
+- Detects circular import dependencies
+- Identifies problematic cycles with mixed static and dynamic imports
+- Automatically comments on pull requests with detailed analysis
+
+## How It Works
+
+1. The app creates a directed graph representing import relationships in the codebase
+
+   ```python
+   for imp in codebase.imports:
+       if imp.from_file and imp.to_file:
+           G.add_edge(
+               imp.to_file.filepath,
+               imp.from_file.filepath,
+               color="red" if getattr(imp, "is_dynamic", False) else "black",
+               label="dynamic" if getattr(imp, "is_dynamic", False) else "static",
+               is_dynamic=getattr(imp, "is_dynamic", False),
+           )
+   ```
+
+1. It identifies strongly connected components (cycles) in the import graph
+
+   ```python
+   cycles = [scc for scc in nx.strongly_connected_components(G) if len(scc) > 1]
+   ```
+
+1. It specifically flags cycles that contain both static and dynamic imports
+
+   ```python
+   dynamic_count = sum(1 for e in edges.values() if e["color"] == "red")
+       static_count = sum(1 for e in edges.values() if e["color"] == "black")
+
+       if dynamic_count > 0 and static_count > 0:
+           mixed_imports[(from_file, to_file)] = {
+               "dynamic": dynamic_count,
+               "static": static_count,
+               "edges": edges,
+           }
+   ```
+
+1. Results are posted as a comment on the pull request
+
+   ```python
+    if problematic_loops:
+       message.append("\n### ⚠️ Problematic Import Cycles")
+       message.append("(Cycles with mixed static and dynamic imports)")
+       for i, cycle in enumerate(problematic_loops, 1):
+           message.append(f"\n#### Problematic Cycle #{i}")
+           message.append("Mixed imports:")
+           for (from_file, to_file), imports in cycle["mixed_imports"].items():
+               message.append(f"\nFrom: `{from_file}`")
+               message.append(f"To: `{to_file}`")
+               message.append(f"- Static imports: {imports['static']}")
+               message.append(f"- Dynamic imports: {imports['dynamic']}")
+
+   create_pr_comment(codebase, event.pull_request, number, "\n".join(message))
+   ```
+
+## Setup
+
+1. Ensure you have the following dependencies:
+
+   - Python 3.13
+   - Modal
+   - Codegen
+   - NetworkX
+   - python-dotenv
+
+1. Set up your environment variables in a `.env` file
+
+   - `GITHUB_TOKEN`: Your GitHub token, configured with `repo` and `workflow` scopes
+
+1. Deploy the app using Modal:
+
+   ```bash
+   modal deploy app.py
+   ```
+
+## Technical Details
+
+The application uses Codegen to parse the codebase and a combination of NetworkX and Codegen to analyze the import relationships. The app is structured as a Modal App with a FastAPI server.
+The analysis runs when a pull request is labeled (`pull_request:labeled` event).
+
+## Output Format
+
+The analysis results are posted as a markdown-formatted comment on the pull request, including:
+
+- Summary statistics
+- Detailed cycle information
+- Warning indicators for problematic import patterns
+
+## Learn More
+
+- [Codegen Documentation](https://docs.codegen.com)
+- [Detecting Import Loops](https://docs.codegen.com/blog/fixing-import-loops)
+
+## Contributing
+
+Feel free to submit issues and enhancement requests!
diff --git a/codegen-examples/examples/github_checks/app.py b/codegen-examples/examples/github_checks/app.py
@@ -0,0 +1,154 @@
+import logging
+
+import modal
+from codegen import CodegenApp, Codebase
+from codegen.extensions.github.types.events.pull_request import PullRequestLabeledEvent
+from codegen.extensions.tools.github.create_pr_comment import create_pr_comment
+from dotenv import load_dotenv
+import networkx as nx
+
+load_dotenv()
+
+logging.basicConfig(level=logging.INFO)
+logger = logging.getLogger(__name__)
+
+cg = CodegenApp(name="codegen-github-checks")
+
+
+def create_graph_from_codebase(repo_path):
+    """Create a directed graph representing import relationships in a codebase."""
+    codebase = Codebase.from_repo(repo_path)
+    G = nx.MultiDiGraph()
+
+    for imp in codebase.imports:
+        if imp.from_file and imp.to_file:
+            G.add_edge(
+                imp.to_file.filepath,
+                imp.from_file.filepath,
+                color="red" if getattr(imp, "is_dynamic", False) else "black",
+                label="dynamic" if getattr(imp, "is_dynamic", False) else "static",
+                is_dynamic=getattr(imp, "is_dynamic", False),
+            )
+    return G
+
+
+def convert_all_calls_to_kwargs(codebase):
+    for file in codebase.files:
+        for function_call in file.function_calls:
+            function_call.convert_args_to_kwargs()
+
+    print("All function calls have been converted to kwargs")
+
+
+def find_import_cycles(G):
+    """Identify strongly connected components (cycles) in the import graph."""
+    cycles = [scc for scc in nx.strongly_connected_components(G) if len(scc) > 1]
+    print(f"🔄 Found {len(cycles)} import cycles.")
+
+    for i, cycle in enumerate(cycles, 1):
+        print(f"\nCycle #{i}: Size {len(cycle)} files")
+        print(f"Total number of imports in cycle: {G.subgraph(cycle).number_of_edges()}")
+
+        print("\nFiles in this cycle:")
+        for file in cycle:
+            print(f"  - {file}")
+
+    return cycles
+
+
+def find_problematic_import_loops(G, cycles):
+    """Identify cycles with both static and dynamic imports between files."""
+    problematic_cycles = []
+
+    for i, scc in enumerate(cycles):
+        if i == 2:
+            continue
+
+        mixed_imports = {}
+        for from_file in scc:
+            for to_file in scc:
+                if G.has_edge(from_file, to_file):
+                    edges = G.get_edge_data(from_file, to_file)
+                    dynamic_count = sum(1 for e in edges.values() if e["color"] == "red")
+                    static_count = sum(1 for e in edges.values() if e["color"] == "black")
+
+                    if dynamic_count > 0 and static_count > 0:
+                        mixed_imports[(from_file, to_file)] = {
+                            "dynamic": dynamic_count,
+                            "static": static_count,
+                            "edges": edges,
+                        }
+
+        if mixed_imports:
+            problematic_cycles.append({"files": scc, "mixed_imports": mixed_imports, "index": i})
+
+    print(f"Found {len(problematic_cycles)} cycles with potentially problematic imports.")
+
+    for i, cycle in enumerate(problematic_cycles):
+        print(f"\n⚠️ Problematic Cycle #{i + 1} (Index {cycle['index']}): Size {len(cycle['files'])} files")
+        print("\nFiles in cycle:")
+        for file in cycle["files"]:
+            print(f"  - {file}")
+        print("\nMixed imports:")
+        for (from_file, to_file), imports in cycle["mixed_imports"].items():
+            print(f"\n  From: {from_file}")
+            print(f"  To:   {to_file}")
+            print(f"  Static imports: {imports['static']}")
+            print(f"  Dynamic imports: {imports['dynamic']}")
+
+    return problematic_cycles
+
+
+@cg.github.event("pull_request:labeled")
+def handle_pr(event: PullRequestLabeledEvent):
+    codebase = Codebase.from_repo(event.repository.get("full_name"), commit=event.pull_request.head.sha)
+
+    G = create_graph_from_codebase(event.repository.get("full_name"))
+    cycles = find_import_cycles(G)
+    problematic_loops = find_problematic_import_loops(G, cycles)
+
+    # Build comment message
+    message = ["### Import Cycle Analysis - GitHub Check\n"]
+
+    if problematic_loops:
+        message.append("\n### ⚠️ Potentially Problematic Import Cycles")
+        message.append("Cycles with mixed static and dynamic imports, which might recquire attention.")
+        for i, cycle in enumerate(problematic_loops, 1):
+            message.append(f"\n#### Problematic Cycle {i}")
+            for (from_file, to_file), imports in cycle["mixed_imports"].items():
+                message.append(f"\nFrom: `{from_file}`")
+                message.append(f"To: `{to_file}`")
+                message.append(f"- Static imports: {imports['static']}")
+                message.append(f"- Dynamic imports: {imports['dynamic']}")
+    else:
+        message.append("\nNo problematic import cycles found! 🎉")
+
+    create_pr_comment(
+        codebase,
+        event.pull_request.number,
+        "\n".join(message),
+    )
+
+    return {
+        "message": "PR event handled",
+        "num_files": len(codebase.files),
+        "num_functions": len(codebase.functions),
+    }
+
+
+base_image = (
+    modal.Image.debian_slim(python_version="3.13")
+    .apt_install("git")
+    .pip_install(
+        "codegen",
+    )
+)
+
+app = modal.App("codegen-test")
+
+
+@app.function(image=base_image, secrets=[modal.Secret.from_dotenv()])
+@modal.asgi_app()
+def fastapi_app():
+    print("Starting codegen fastapi app")
+    return cg.app
