EagleCast

cmd/utils.go

@@ -0,0 +1,114 @@
+package main
+
+import (
+	"crypto/rand"
+	"fmt"
+	"net/url"
+	"path/filepath"
+	"regexp"
+	"slices"
+	"strconv"
+	"strings"
+)
+
+var (
+	regexpSpaces = regexp.MustCompile(`[\s]+`)
+)
+
+// inArray checks if a string is present in a list of strings.
+func inArray(val string, vals []string) (ok bool) {
+	return slices.Contains(vals, val)
+}
+
+// makeFilename sanitizes a filename (user supplied upload filenames).
+func makeFilename(fName string) string {
+	name := strings.TrimSpace(fName)
+	if name == "" {
+		name, _ = generateRandomString(10)
+	}
+	// replace whitespace with "-"
+	name = regexpSpaces.ReplaceAllString(name, "-")
+	return filepath.Base(name)
+}
+
+// appendSuffixToFilename adds a string suffix to the filename while keeping the file extension.
+func appendSuffixToFilename(filename, suffix string) string {
+	ext := filepath.Ext(filename)
+	name := strings.TrimSuffix(filename, ext)
+	return fmt.Sprintf("%s_%s%s", name, suffix, ext)
+}
+
+// makeMsgTpl takes a page title, heading, and message and returns
+// a msgTpl that can be rendered as an HTML view. This is used for
+// rendering arbitrary HTML views with error and success messages.
+func makeMsgTpl(pageTitle, heading, msg string) msgTpl {
+	if heading == "" {
+		heading = pageTitle
+	}
+	err := msgTpl{}
+	err.Title = pageTitle
+	err.MessageTitle = heading
+	err.Message = msg
+	return err
+}
+
+// parseStringIDs takes a slice of numeric string IDs and
+// parses each number into an int64 and returns a slice of the
+// resultant values.
+func parseStringIDs(s []string) ([]int, error) {
+	vals := make([]int, 0, len(s))
+	for _, v := range s {
+		i, err := strconv.Atoi(v)
+		if err != nil {
+			return nil, err
+		}
+
+		if i < 1 {
+			return nil, fmt.Errorf("%d is not a valid ID", i)
+		}
+
+		vals = append(vals, i)
+	}
+
+	return vals, nil
+}
+
+// generateRandomString generates a cryptographically random, alphanumeric string of length n.
+func generateRandomString(n int) (string, error) {
+	const dictionary = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
+	var bytes = make([]byte, n)
+
+	if _, err := rand.Read(bytes); err != nil {
+		return "", err
+	}
+	for k, v := range bytes {
+		bytes[k] = dictionary[v%byte(len(dictionary))]
+	}
+
+	return string(bytes), nil
+}
+
+// strHasLen checks if the given string has a length within min-max.
+func strHasLen(str string, min, max int) bool {
+	return len(str) >= min && len(str) <= max
+}
+
+// getQueryInts parses the list of given query param values into ints.
+func getQueryInts(param string, qp url.Values) ([]int, error) {
+	var out []int
+	if vals, ok := qp[param]; ok {
+		for _, v := range vals {
+			if v == "" {
+				continue
+			}
+
+			listID, err := strconv.Atoi(v)
+			if err != nil {
+				return nil, err
+			}
+			out = append(out, listID)
+		}
+	}
+
+	return out, nil
+}