feat(ldap): LdapEndpoint + FallbackServers entry parser

2026-08-10 16:32:27 -04:00
parent 0c1702acbc
commit 5fbf53601c
2 changed files with 95 additions and 0 deletions
@@ -0,0 +1,60 @@
+namespace ZB.MOM.WW.Auth.Ldap.Internal;
+
+/// <summary>A single LDAP server endpoint resolved from configuration.</summary>
+internal sealed record LdapEndpoint(string Host, int Port)
+{
+    /// <summary>Renders the endpoint as <c>host:port</c> — the form used in failover log messages.</summary>
+    public override string ToString() => $"{Host}:{Port}";
+}
+
+/// <summary>
+/// Parses <c>FallbackServers</c> entries: <c>"host"</c> (adopts the caller's default port)
+/// or <c>"host:port"</c>. IPv6 literals are not supported — use a DNS name.
+/// </summary>
+internal static class LdapEndpointParser
+{
+    /// <summary>
+    /// Attempts to parse a single <c>FallbackServers</c> entry.
+    /// </summary>
+    /// <param name="entry">The configured entry, <c>"host"</c> or <c>"host:port"</c>. Surrounding whitespace is tolerated.</param>
+    /// <param name="defaultPort">Port adopted when the entry carries no explicit one.</param>
+    /// <param name="endpoint">The parsed endpoint on success; undefined otherwise.</param>
+    /// <param name="error">A human-readable reason on failure; empty on success.</param>
+    /// <returns><see langword="true"/> when the entry parsed.</returns>
+    public static bool TryParse(string entry, int defaultPort, out LdapEndpoint endpoint, out string error)
+    {
+        endpoint = null!;
+        error = "";
+
+        if (string.IsNullOrWhiteSpace(entry))
+        {
+            error = "entry is empty or whitespace";
+            return false;
+        }
+
+        var parts = entry.Trim().Split(':');
+        if (parts.Length > 2)
+        {
+            error = $"entry \"{entry.Trim()}\" contains more than one ':' " +
+                    "(IPv6 literals are not supported — use a DNS name)";
+            return false;
+        }
+
+        var host = parts[0].Trim();
+        if (host.Length == 0)
+        {
+            error = $"entry \"{entry.Trim()}\" has an empty host";
+            return false;
+        }
+
+        var port = defaultPort;
+        if (parts.Length == 2 && (!int.TryParse(parts[1].Trim(), out port) || port is < 1 or > 65535))
+        {
+            error = $"entry \"{entry.Trim()}\" has an invalid port (must be 1–65535)";
+            return false;
+        }
+
+        endpoint = new LdapEndpoint(host, port);
+        return true;
+    }
+}