Cybersecurity-Projects/PROJECTS/beginner/simple-vulnerability-scanner/internal/requirements/parser.go

108 lines
2.3 KiB
Go

/*
©AngelaMos | 2026
parser.go
requirements.txt line-by-line parser handling PEP 508 syntax
Skips blank lines, comment lines, and pip flag lines (starting with -).
Strips inline comments before parsing each line. Handles extras in
brackets and environment markers after semicolons, matching the behavior
of the pyproject parser.
Key exports:
ParseFile - reads a requirements.txt and returns all dependency declarations
Connects to:
update.go - called when the target file ends in .txt
types.go - returns []Dependency
*/
package requirements
import (
"bufio"
"fmt"
"os"
"strings"
"github.com/CarterPerez-dev/angela/pkg/types"
)
// ParseFile reads a requirements.txt and extracts all dependency declarations
func ParseFile(path string) ([]types.Dependency, error) {
f, err := os.Open(path) //nolint:gosec
if err != nil {
if os.IsNotExist(err) {
return nil, fmt.Errorf(
"open %s: file not found", path,
)
}
return nil, fmt.Errorf("read %s: %w", path, err)
}
defer func() { _ = f.Close() }() //nolint:errcheck
var deps []types.Dependency
scanner := bufio.NewScanner(f)
for scanner.Scan() {
line := strings.TrimSpace(scanner.Text())
if line == "" ||
strings.HasPrefix(line, "#") ||
strings.HasPrefix(line, "-") {
continue
}
if idx := strings.Index(line, " #"); idx >= 0 {
line = strings.TrimSpace(line[:idx])
}
dep := parseLine(line)
if dep.Name != "" {
deps = append(deps, dep)
}
}
if err := scanner.Err(); err != nil {
return nil, fmt.Errorf("read %s: %w", path, err)
}
if len(deps) == 0 {
return nil, fmt.Errorf(
"%s: no dependencies found", path,
)
}
return deps, nil
}
func parseLine(s string) types.Dependency {
var dep types.Dependency
if idx := strings.Index(s, ";"); idx >= 0 {
dep.Markers = strings.TrimSpace(s[idx+1:])
s = strings.TrimSpace(s[:idx])
}
if start := strings.Index(s, "["); start >= 0 {
end := strings.Index(s, "]")
if end > start {
for _, e := range strings.Split(s[start+1:end], ",") {
dep.Extras = append(
dep.Extras,
strings.TrimSpace(e),
)
}
s = s[:start] + s[end+1:]
}
}
if idx := strings.IndexAny(s, "><=!~"); idx >= 0 {
dep.Name = strings.TrimSpace(s[:idx])
dep.Spec = strings.TrimSpace(s[idx:])
} else {
dep.Name = strings.TrimSpace(s)
}
return dep
}