Add support for storage command and crawler output

Partially addresses issue #3 by adding a simple `magellan list devices` command to list storage devices. To close the issue, this PR still requires including storage device information in the `crawler`'s output.

Reviewed-on: towk/magellan-ng#5

internal/urlx/url.go

@@ -0,0 +1,124 @@
+package urlx
+
+import (
+	"fmt"
+	"net/url"
+	"strings"
+
+	"github.com/rs/zerolog/log"
+)
+
+func Sanitize(uri string) (string, error) {
+	// URL sanitanization for host argument
+	parsedURI, err := url.ParseRequestURI(uri)
+	if err != nil {
+		return "", fmt.Errorf("failed to parse URI: %w", err)
+	}
+	// Remove any trailing slashes
+	parsedURI.Path = strings.TrimSuffix(parsedURI.Path, "/")
+	// Collapse any doubled slashes
+	parsedURI.Path = strings.ReplaceAll(parsedURI.Path, "//", "/")
+	return parsedURI.String(), nil
+}
+
+func TrimScheme(uri string) string {
+	const prefix = "https://"
+	if strings.Contains(uri, prefix) {
+		return strings.TrimPrefix(uri, prefix)
+	}
+	return uri
+}
+
+// FormatHosts() takes a list of hosts and ports and builds full URLs in the
+// form of scheme://host:port. If no scheme is provided, it will use "https" by
+// default.
+//
+// Returns a 2D string slice where each slice contains URL host strings for each
+// port. The intention is to have all of the URLs for a single host combined into
+// a single slice to initiate one goroutine per host, but making request to multiple
+// ports.
+func FormatHosts(hosts []string, ports []int, scheme string, verbose bool) [][]string {
+	// format each positional arg as a complete URL
+	var formattedHosts [][]string
+	for _, host := range hosts {
+		uri, err := url.ParseRequestURI(host)
+		if err != nil {
+			if verbose {
+				log.Warn().Msgf("invalid URI parsed: %s", host)
+			}
+			continue
+		}
+
+		// check if scheme is set, if not set it with flag or default value ('https' if flag is not set)
+		if uri.Scheme == "" {
+			if scheme != "" {
+				uri.Scheme = scheme
+			} else {
+				// hardcoded assumption
+				uri.Scheme = "https"
+			}
+		}
+
+		// tidy up slashes and update arg with new value
+		uri.Path = strings.TrimSuffix(uri.Path, "/")
+		uri.Path = strings.ReplaceAll(uri.Path, "//", "/")
+
+		// for hosts with unspecified ports, add ports to scan from flag
+		if uri.Port() == "" {
+			var tmp []string
+			for _, port := range ports {
+				uri.Host += fmt.Sprintf(":%d", port)
+				tmp = append(tmp, uri.String())
+			}
+			formattedHosts = append(formattedHosts, tmp)
+		} else {
+			formattedHosts = append(formattedHosts, []string{uri.String()})
+		}
+
+	}
+	return formattedHosts
+}
+
+// FormatIPs() takes a list of IP addresses and ports and builds full URLs in the
+// form of scheme://host:port. If no scheme is provided, it will use "https" by
+// default.
+//
+// Returns a 2D string slice where each slice contains URL host strings for each
+// port. The intention is to have all of the URLs for a single host combined into
+// a single slice to initiate one goroutine per host, but making request to multiple
+// ports.
+func FormatIPs(ips []string, ports []int, scheme string, verbose bool) [][]string {
+	// format each positional arg as a complete URL
+	var formattedHosts [][]string
+	for _, ip := range ips {
+		if scheme == "" {
+			scheme = "https"
+		}
+		// make an entirely new object since we're expecting just IPs
+		uri := &url.URL{
+			Scheme: scheme,
+			Host:   ip,
+		}
+
+		// tidy up slashes and update arg with new value
+		uri.Path = strings.ReplaceAll(uri.Path, "//", "/")
+		uri.Path = strings.TrimSuffix(uri.Path, "/")
+
+		// for hosts with unspecified ports, add ports to scan from flag
+		if uri.Port() == "" {
+			if len(ports) == 0 {
+				ports = append(ports, 443)
+			}
+			var tmp []string
+			for _, port := range ports {
+				uri.Host += fmt.Sprintf(":%d", port)
+				tmp = append(tmp, uri.String())
+			}
+			formattedHosts = append(formattedHosts, tmp)
+		} else {
+			formattedHosts = append(formattedHosts, []string{uri.String()})
+		}
+
+	}
+	return formattedHosts
+}