feat(date): Adding date computing

Signed-off-by: Vincent Boutour <[email protected]>

README.md

@@ -98,7 +98,7 @@ Usage of exas:
   -userAgent string
         [alcotest] User-Agent for check {EXAS_USER_AGENT} (default "Alcotest")
   -workDir string
-        [vith] Working directory for direct access requests {EXAS_WORK_DIR}
+        [exas] Working directory for direct access requests {EXAS_WORK_DIR}
   -writeTimeout string
         [server] Write Timeout {EXAS_WRITE_TIMEOUT} (default "2m")
 ```

pkg/exas/date.go

@@ -0,0 +1,56 @@
+package exas
+
+import (
+	"errors"
+	"fmt"
+	"time"
+)
+
+var (
+	exifDates = []string{
+		"DateCreated",
+		"CreateDate",
+	}
+
+	datePatterns = []string{
+		"2006:01:02 15:04:05MST",
+		"2006:01:02 15:04:05-07:00",
+		"2006:01:02 15:04:05Z07:00",
+		"2006:01:02 15:04:05",
+		"2006:01:02",
+		"01/02/2006 15:04:05",
+		"1/02/2006 15:04:05",
+	}
+)
+
+func getDate(data map[string]interface{}) (time.Time, error) {
+	for _, exifDate := range exifDates {
+		rawCreateDate, ok := data[exifDate]
+		if !ok {
+			continue
+		}
+
+		createDateStr, ok := rawCreateDate.(string)
+		if !ok {
+			return time.Time{}, fmt.Errorf("key `%s` is not a string", exifDate)
+		}
+
+		createDate, err := parseDate(createDateStr)
+		if err == nil {
+			return createDate, nil
+		}
+	}
+
+	return time.Time{}, nil
+}
+
+func parseDate(raw string) (time.Time, error) {
+	for _, pattern := range datePatterns {
+		createDate, err := time.Parse(pattern, raw)
+		if err == nil {
+			return createDate, nil
+		}
+	}
+
+	return time.Time{}, errors.New("no matching pattern")
+}

pkg/exas/exas.go

@@ -41,7 +41,7 @@ type Config struct {
 func Flags(fs *flag.FlagSet, prefix string, overrides ...flags.Override) Config {
 	return Config{
 		tmpFolder:  flags.New(prefix, "exas", "TmpFolder").Default("/tmp", overrides).Label("Folder used for temporary files storage").ToString(fs),
-		workingDir: flags.New(prefix, "vith", "WorkDir").Default("", overrides).Label("Working directory for direct access requests").ToString(fs),
+		workingDir: flags.New(prefix, "exas", "WorkDir").Default("", overrides).Label("Working directory for direct access requests").ToString(fs),
 	}
 }
 
@@ -104,6 +104,13 @@ func (a App) answerExif(input string, w http.ResponseWriter) {
 		exifData = exifs[0]
 	}
 
+	if date, err := getDate(exifData); err != nil {
+		httperror.InternalServerError(w, fmt.Errorf("unable to parse date: %s", err))
+		return
+	} else if !date.IsZero() {
+		exifData["date"] = date
+	}
+
 	if a.geocodeApp.Enabled() {
 		if err := a.geocodeApp.AppendGeocoding(exifData); err != nil {
 			httperror.InternalServerError(w, fmt.Errorf("unable to append geocoding: %s", err))