added epss enricher

enricher/epss/epss.go

@@ -0,0 +1,108 @@
+package epss
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"github.com/google/uuid"
+	"github.com/quay/claircore"
+	"github.com/quay/claircore/libvuln/driver"
+	"github.com/quay/zlog"
+	"io"
+	"net/http"
+	"net/url"
+	"os"
+	"path"
+	"strings"
+	"time"
+)
+
+var (
+	_ driver.Enricher          = (*Enricher)(nil)
+	_ driver.EnrichmentUpdater = (*Enricher)(nil)
+
+	defaultFeed *url.URL
+)
+
+const (
+	// DefaultFeeds is the default place to look for EPSS feeds.
+	// epss_scores-YYYY-MM-DD.csv.gz needs to be specified to get all data
+	DefaultRootUrl = `https://epss.cyentia.com/`
+)
+
+// Enricher provides EPSS data as enrichments to a VulnerabilityReport.
+//
+// Configure must be called before any other methods.
+type Enricher struct {
+	driver.NoopUpdater
+	c        *http.Client
+	feed     *url.URL
+	feedPath string
+}
+
+func (e Enricher) FetchEnrichment(ctx context.Context, fingerprint driver.Fingerprint) (io.ReadCloser, driver.Fingerprint, error) {
+	ctx = zlog.ContextWithValues(ctx, "component", "enricher/epss/Enricher/FetchEnrichment")
+	currentDate := time.Now()
+	formattedDate := currentDate.Format("2006-01-02")
+	// Force a new hint, to signal updaters that this is new data.
+	newUUID := uuid.New()
+	hint := driver.Fingerprint(newUUID.String())
+	zlog.Info(ctx).Str("hint", string(hint)).Msg("starting fetch")
+	out, err := os.CreateTemp("", "enricher.epss.gz")
+	if err != nil {
+		return nil, hint, err
+	}
+	var success bool
+	defer func() {
+		if !success {
+			if err := out.Close(); err != nil {
+				zlog.Warn(ctx).Err(err).Msg("unable to close spool")
+			}
+		}
+	}()
+	if e.feedPath == "" || !strings.HasSuffix(e.feedPath, ".gz") {
+		filePath := fmt.Sprintf("epss_scores-%s.csv.gz", formattedDate)
+		e.feedPath = path.Join(DefaultRootUrl, filePath)
+	}
+	// Make an HTTP GET request to download the .gz file
+	resp, err := http.Get(e.feedPath)
+	if err != nil {
+		return nil, "", fmt.Errorf("failed to fetch file from %s: %w", e.feedPath, err)
+	}
+	defer resp.Body.Close()
+
+	// Check for a successful response
+	if resp.StatusCode != http.StatusOK {
+		return nil, "", fmt.Errorf("failed to fetch file: received status %d", resp.StatusCode)
+	}
+
+	_, err = io.Copy(out, resp.Body)
+	if err != nil {
+		out.Close()
+		return nil, "", fmt.Errorf("failed to write to temporary file: %w", err)
+	}
+
+	// Reset file pointer to the beginning
+	_, err = out.Seek(0, io.SeekStart)
+	if err != nil {
+		out.Close()
+		return nil, "", fmt.Errorf("failed to reset file pointer: %w", err)
+	}
+	success = true
+	return out, hint, nil
+}
+
+func (e Enricher) ParseEnrichment(ctx context.Context, closer io.ReadCloser) ([]driver.EnrichmentRecord, error) {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (e Enricher) Name() string {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (e Enricher) Enrich(ctx context.Context, getter driver.EnrichmentGetter, report *claircore.VulnerabilityReport) (string, []json.RawMessage, error) {
+	//TODO implement me
+	panic("implement me")
+}