markdown: Add Markdown formatter

CHANGELOG.md

@@ -8,6 +8,12 @@ All versions prior to 0.0.9 are untracked.
 
 ## [Unreleased]
 
+### Added
+
+* Output formats: `pip-audit` now supports a Markdown format
+  (`--format=markdown`) which renders results as a set of Markdown tables.
+  ([#312](https://github.com/trailofbits/pip-audit/pull/312))
+
 ## [2.3.4]
 
 ### Fixed

README.md

@@ -153,8 +153,8 @@ optional arguments:
                         used multiple times (default: None)
   -f FORMAT, --format FORMAT
                         the format to emit audit results in (choices: columns,
-                        json, cyclonedx-json, cyclonedx-xml) (default:
-                        columns)
+                        json, cyclonedx-json, cyclonedx-xml, markdown)
+                        (default: columns)
   -s SERVICE, --vulnerability-service SERVICE
                         the vulnerability service to audit dependencies
                         against (choices: osv, pypi) (default: pypi)

pip_audit/_cli.py

@@ -23,7 +23,13 @@
 )
 from pip_audit._dependency_source.interface import DependencySourceError
 from pip_audit._fix import ResolvedFixVersion, SkippedFixVersion, resolve_fix_versions
-from pip_audit._format import ColumnsFormat, CycloneDxFormat, JsonFormat, VulnerabilityFormat
+from pip_audit._format import (
+    ColumnsFormat,
+    CycloneDxFormat,
+    JsonFormat,
+    MarkdownFormat,
+    VulnerabilityFormat,
+)
 from pip_audit._service import OsvService, PyPIService, VulnerabilityService
 from pip_audit._service.interface import ConnectionError as VulnServiceConnectionError
 from pip_audit._service.interface import ResolvedDependency, SkippedDependency
@@ -44,6 +50,7 @@ class OutputFormatChoice(str, enum.Enum):
     Json = "json"
     CycloneDxJson = "cyclonedx-json"
     CycloneDxXml = "cyclonedx-xml"
+    Markdown = "markdown"
 
     def to_format(self, output_desc: bool) -> VulnerabilityFormat:
         if self is OutputFormatChoice.Columns:
@@ -54,6 +61,8 @@ def to_format(self, output_desc: bool) -> VulnerabilityFormat:
             return CycloneDxFormat(inner_format=CycloneDxFormat.InnerFormat.Json)
         elif self is OutputFormatChoice.CycloneDxXml:
             return CycloneDxFormat(inner_format=CycloneDxFormat.InnerFormat.Xml)
+        elif self is OutputFormatChoice.Markdown:
+            return MarkdownFormat(output_desc)
         else:
             assert_never(self)
 

pip_audit/_format/__init__.py

@@ -6,10 +6,12 @@
 from .cyclonedx import CycloneDxFormat
 from .interface import VulnerabilityFormat
 from .json import JsonFormat
+from .markdown import MarkdownFormat
 
 __all__ = [
     "ColumnsFormat",
     "CycloneDxFormat",
     "VulnerabilityFormat",
     "JsonFormat",
+    "MarkdownFormat",
 ]

pip_audit/_format/markdown.py

@@ -0,0 +1,135 @@
+"""
+Functionality for formatting vulnerability results as a Markdown table.
+"""
+
+import os
+from typing import Dict, List, Optional, cast
+
+from packaging.version import Version
+
+import pip_audit._fix as fix
+import pip_audit._service as service
+
+from .interface import VulnerabilityFormat
+
+
+class MarkdownFormat(VulnerabilityFormat):
+    """
+    An implementation of `VulnerabilityFormat` that formats vulnerability results as a set of
+    Markdown tables.
+    """
+
+    def __init__(self, output_desc: bool) -> None:
+        """
+        Create a new `MarkdownFormat`.
+
+        `output_desc` is a flag to determine whether descriptions for each vulnerability should be
+        included in the output as they can be quite long and make the output difficult to read.
+        """
+        self.output_desc = output_desc
+
+    @property
+    def is_manifest(self) -> bool:
+        """
+        See `VulnerabilityFormat.is_manifest`.
+        """
+        return False
+
+    def format(
+        self,
+        result: Dict[service.Dependency, List[service.VulnerabilityResult]],
+        fixes: List[fix.FixVersion],
+    ) -> str:
+        """
+        Returns a Markdown formatted string representing a set of vulnerability results and applied
+        fixes.
+        """
+        output = self._format_vuln_results(result, fixes)
+        skipped_deps_output = self._format_skipped_deps(result)
+        if skipped_deps_output:
+            # If we wrote the results table already, we need to add some line breaks to ensure that
+            # the skipped dependency table renders correctly.
+            if output:
+                output += os.linesep + os.linesep
+            output += skipped_deps_output
+        return output
+
+    def _format_vuln_results(
+        self,
+        result: Dict[service.Dependency, List[service.VulnerabilityResult]],
+        fixes: List[fix.FixVersion],
+    ) -> str:
+        header = "Name | Version | ID | Fix Versions"
+        border = "--- | --- | --- | ---"
+        if fixes:
+            header += " | Applied Fix"
+            border += " | ---"
+        if self.output_desc:
+            header += " | Description"
+            border += " | ---"
+
+        vuln_rows: List[str] = []
+        for dep, vulns in result.items():
+            if dep.is_skipped():
+                continue
+            dep = cast(service.ResolvedDependency, dep)
+            applied_fix = next((f for f in fixes if f.dep == dep), None)
+            for vuln in vulns:
+                vuln_rows.append(self._format_vuln(dep, vuln, applied_fix))
+
+        if not vuln_rows:
+            return str()
+
+        return header + os.linesep + border + os.linesep + os.linesep.join(vuln_rows)
+
+    def _format_vuln(
+        self,
+        dep: service.ResolvedDependency,
+        vuln: service.VulnerabilityResult,
+        applied_fix: Optional[fix.FixVersion],
+    ) -> str:
+        vuln_text = (
+            f"{dep.canonical_name} | {dep.version} | {vuln.id} | "
+            f"{self._format_fix_versions(vuln.fix_versions)}"
+        )
+        if applied_fix is not None:
+            vuln_text += f" | {self._format_applied_fix(applied_fix)}"
+        if self.output_desc:
+            vuln_text += f" | {vuln.description}"
+        return vuln_text
+
+    def _format_fix_versions(self, fix_versions: List[Version]) -> str:
+        return ",".join([str(version) for version in fix_versions])
+
+    def _format_applied_fix(self, applied_fix: fix.FixVersion) -> str:
+        if applied_fix.is_skipped():
+            applied_fix = cast(fix.SkippedFixVersion, applied_fix)
+            return (
+                f"Failed to fix {applied_fix.dep.canonical_name} ({applied_fix.dep.version}): "
+                f"{applied_fix.skip_reason}"
+            )
+        applied_fix = cast(fix.ResolvedFixVersion, applied_fix)
+        return (
+            f"Successfully upgraded {applied_fix.dep.canonical_name} ({applied_fix.dep.version} "
+            f"=> {applied_fix.version})"
+        )
+
+    def _format_skipped_deps(
+        self, result: Dict[service.Dependency, List[service.VulnerabilityResult]]
+    ) -> str:
+        header = "Name | Skip Reason"
+        border = "--- | ---"
+
+        skipped_dep_rows: List[str] = []
+        for dep, _ in result.items():
+            if dep.is_skipped():
+                dep = cast(service.SkippedDependency, dep)
+                skipped_dep_rows.append(self._format_skipped_dep(dep))
+
+        if not skipped_dep_rows:
+            return str()
+
+        return header + os.linesep + border + os.linesep + os.linesep.join(skipped_dep_rows)
+
+    def _format_skipped_dep(self, dep: service.SkippedDependency) -> str:
+        return f"{dep.name} | {dep.skip_reason}"

test/format/test_markdown.py

@@ -0,0 +1,75 @@
+import pytest
+
+import pip_audit._format as format
+
+
+@pytest.mark.parametrize("output_desc", [True, False])
+def test_columns_not_manifest(output_desc):
+    fmt = format.MarkdownFormat(output_desc)
+    assert not fmt.is_manifest
+
+
+def test_markdown(vuln_data):
+    markdown_format = format.MarkdownFormat(True)
+    expected_markdown = """Name | Version | ID | Fix Versions | Description
+--- | --- | --- | --- | ---
+foo | 1.0 | VULN-0 | 1.1,1.4 | The first vulnerability
+foo | 1.0 | VULN-1 | 1.0 | The second vulnerability
+bar | 0.1 | VULN-2 |  | The third vulnerability"""
+    assert markdown_format.format(vuln_data, list()) == expected_markdown
+
+
+def test_markdown_no_desc(vuln_data):
+    markdown_format = format.MarkdownFormat(False)
+    expected_markdown = """Name | Version | ID | Fix Versions
+--- | --- | --- | ---
+foo | 1.0 | VULN-0 | 1.1,1.4
+foo | 1.0 | VULN-1 | 1.0
+bar | 0.1 | VULN-2 | """
+    assert markdown_format.format(vuln_data, list()) == expected_markdown
+
+
+def test_markdown_skipped_dep(vuln_data_skipped_dep):
+    markdown_format = format.MarkdownFormat(False)
+    expected_markdown = """Name | Version | ID | Fix Versions
+--- | --- | --- | ---
+foo | 1.0 | VULN-0 | 1.1,1.4
+
+Name | Skip Reason
+--- | ---
+bar | skip-reason"""
+    assert markdown_format.format(vuln_data_skipped_dep, list()) == expected_markdown
+
+
+def test_markdown_no_vuln_data(no_vuln_data):
+    markdown_format = format.MarkdownFormat(False)
+    expected_markdown = str()
+    assert markdown_format.format(no_vuln_data, list()) == expected_markdown
+
+
+def test_markdown_no_vuln_data_skipped_dep(no_vuln_data_skipped_dep):
+    markdown_format = format.MarkdownFormat(False)
+    expected_markdown = """Name | Skip Reason
+--- | ---
+bar | skip-reason"""
+    assert markdown_format.format(no_vuln_data_skipped_dep, list()) == expected_markdown
+
+
+def test_markdown_fix(vuln_data, fix_data):
+    markdown_format = format.MarkdownFormat(False)
+    expected_markdown = """Name | Version | ID | Fix Versions | Applied Fix
+--- | --- | --- | --- | ---
+foo | 1.0 | VULN-0 | 1.1,1.4 | Successfully upgraded foo (1.0 => 1.8)
+foo | 1.0 | VULN-1 | 1.0 | Successfully upgraded foo (1.0 => 1.8)
+bar | 0.1 | VULN-2 |  | Successfully upgraded bar (0.1 => 0.3)"""
+    assert markdown_format.format(vuln_data, fix_data) == expected_markdown
+
+
+def test_markdown_skipped_fix(vuln_data, skipped_fix_data):
+    markdown_format = format.MarkdownFormat(False)
+    expected_markdown = """Name | Version | ID | Fix Versions | Applied Fix
+--- | --- | --- | --- | ---
+foo | 1.0 | VULN-0 | 1.1,1.4 | Successfully upgraded foo (1.0 => 1.8)
+foo | 1.0 | VULN-1 | 1.0 | Successfully upgraded foo (1.0 => 1.8)
+bar | 0.1 | VULN-2 |  | Failed to fix bar (0.1): skip-reason"""
+    assert markdown_format.format(vuln_data, skipped_fix_data) == expected_markdown