syft/imgbom/cataloger/common/generic_cataloger.go

102 lines
3.2 KiB
Go

package common
import (
"strings"
"github.com/anchore/imgbom/imgbom/pkg"
"github.com/anchore/imgbom/imgbom/scope"
"github.com/anchore/imgbom/internal/log"
"github.com/anchore/stereoscope/pkg/file"
)
// GenericCataloger implements the Catalog interface and is responsible for dispatching the proper parser function for
// a given path or glob pattern. This is intended to be reusable across many package cataloger types.
type GenericCataloger struct {
globParsers map[string]ParserFn
pathParsers map[string]ParserFn
selectedFiles []file.Reference
parsers map[file.Reference]ParserFn
}
// NewGenericCataloger if provided path-to-parser-function and glob-to-parser-function lookups creates a GenericCataloger
func NewGenericCataloger(pathParsers map[string]ParserFn, globParsers map[string]ParserFn) GenericCataloger {
return GenericCataloger{
globParsers: globParsers,
pathParsers: pathParsers,
selectedFiles: make([]file.Reference, 0),
parsers: make(map[file.Reference]ParserFn),
}
}
// register pairs a set of file references with a parser function for future cataloging (when the file contents are resolved)
func (a *GenericCataloger) register(files []file.Reference, parser ParserFn) {
a.selectedFiles = append(a.selectedFiles, files...)
for _, f := range files {
a.parsers[f] = parser
}
}
// clear deletes all registered file-reference-to-parser-function pairings from former SelectFiles() and register() calls
func (a *GenericCataloger) clear() {
a.selectedFiles = make([]file.Reference, 0)
a.parsers = make(map[file.Reference]ParserFn)
}
// SelectFiles takes a set of file trees and resolves and file references of interest for future cataloging
func (a *GenericCataloger) SelectFiles(resolver scope.FileResolver) []file.Reference {
// select by exact path
for path, parser := range a.pathParsers {
files, err := resolver.FilesByPath(file.Path(path))
if err != nil {
log.Errorf("cataloger failed to select files by path: %w", err)
}
if files != nil {
a.register(files, parser)
}
}
// select by glob pattern
for globPattern, parser := range a.globParsers {
fileMatches, err := resolver.FilesByGlob(globPattern)
if err != nil {
log.Errorf("failed to find files by glob: %s", globPattern)
}
if fileMatches != nil {
a.register(fileMatches, parser)
}
}
return a.selectedFiles
}
// Catalog takes a set of file contents and uses any configured parser functions to resolve and return discovered packages
func (a *GenericCataloger) Catalog(contents map[file.Reference]string, upstreamMatcher string) ([]pkg.Package, error) {
defer a.clear()
packages := make([]pkg.Package, 0)
for reference, parser := range a.parsers {
content, ok := contents[reference]
if !ok {
log.Errorf("cataloger '%s' missing file content: %+v", upstreamMatcher, reference)
continue
}
entries, err := parser(string(reference.Path), strings.NewReader(content))
if err != nil {
// TODO: should we fail? or only log?
log.Errorf("cataloger '%s' failed to parse entries (reference=%+v): %w", upstreamMatcher, reference, err)
continue
}
for _, entry := range entries {
entry.FoundBy = upstreamMatcher
entry.Source = []file.Reference{reference}
packages = append(packages, entry)
}
}
return packages, nil
}