Remove custom precondition; use Discord permissions

Commands/CommandsBase.cs

@@ -73,13 +73,6 @@ public class CommandsBase : InteractionModuleBase<ShardedInteractionContext> {
         return $"**{username}**#{user.Discriminator}";
     }
 
-    /// <summary>
-    /// Checks if the given user can be considered a guild admin ('Manage Server' is set).
-    /// </summary>
-    // TODO replace this with a precondition, or there's also a new permission scheme going around?
-    protected static bool IsUserAdmin(SocketGuildUser user)
-        => user.GuildPermissions.Administrator || user.GuildPermissions.ManageGuild;
-
     /// <summary>
     /// Checks if the member cache for the specified guild needs to be filled, and sends a request if needed.
     /// </summary>

Commands/ConfigCommands.cs

@@ -1,19 +1,16 @@
 using Discord.Interactions;
 
 namespace WorldTime.Commands;
-[Group("config", HelpSettings)]
+[Group("config", "Configuration commands for World Time.")]
+[DefaultMemberPermissions(GuildPermission.ManageGuild)]
+[EnabledInDm(false)]
 public class ConfigCommands : CommandsBase {
-    internal const string HelpSettings = "Configuration commands for World Time.";
     internal const string HelpUse12 = "Sets whether to use the 12-hour (AM/PM) format in time zone listings.";
+    internal const string HelpSetFor = "Sets/updates time zone for a given user.";
+    internal const string HelpRemoveFor = "Removes time zone for a given user.";
 
-    [RequireGuildContext]
     [SlashCommand("use-12hour", HelpUse12)]
     public async Task Cmd12Hour([Summary(description: "True to enable, False to disable.")] bool setting) {
-        if (!IsUserAdmin((SocketGuildUser)Context.User)) {
-            await RespondAsync(ErrNotAllowed, ephemeral: true);
-            return;
-        }
-
         using var db = DbContext;
         var gs = db.GuildSettings.Where(r => r.GuildId == Context.Guild.Id).SingleOrDefault();
         if (gs == null) {
@@ -25,4 +22,28 @@ public class ConfigCommands : CommandsBase {
         await db.SaveChangesAsync();
         await RespondAsync($":white_check_mark: Time listing set to **{(setting ? "AM/PM" : "24 hour")}** format.");
     }
+
+    [SlashCommand("set-for", HelpSetFor)]
+    public async Task CmdSetFor([Summary(description: "The user whose time zone to modify.")] SocketGuildUser user,
+                                 [Summary(description: "The new time zone to set.")] string zone) {
+        // Extract parameters
+        var newtz = ParseTimeZone(zone);
+        if (newtz == null) {
+            await RespondAsync(ErrInvalidZone);
+            return;
+        }
+
+        using var db = DbContext;
+        db.UpdateUser(user, newtz);
+        await RespondAsync($":white_check_mark: Time zone for **{user}** set to **{newtz}**.");
+    }
+
+    [SlashCommand("remove-for", HelpRemoveFor)]
+    public async Task CmdRemoveFor([Summary(description: "The user whose time zone to remove.")] SocketGuildUser user) {
+        using var db = DbContext;
+        if (db.DeleteUser(user))
+            await RespondAsync($":white_check_mark: Removed zone information for {user}.");
+        else
+            await RespondAsync($":white_check_mark: No time zone is set for {user}.");
+    }
 }

Commands/RequireGuildContextAttribute.cs

@@ -1,14 +0,0 @@
-using Discord.Interactions;
-
-namespace WorldTime.Commands;
-/// <summary>
-/// Implements the included precondition from Discord.Net, requiring a guild context while using our custom error message.
-/// </summary>
-class RequireGuildContextAttribute : RequireContextAttribute {
-    public const string Error = "Command not received within a guild context.";
-    public const string Reply = ":x: This command is only available within a server.";
-
-    public override string ErrorMessage => Error;
-
-    public RequireGuildContextAttribute() : base(ContextType.Guild) { }
-}

Commands/UserCommands.cs

@@ -10,16 +10,15 @@ public class UserCommands : CommandsBase {
         + $"`/remove` - {HelpRemove}";
     const string EmbedHelpField2 =
         $"`/config use-12hour` - {ConfigCommands.HelpUse12}\n"
-        + $"`/set-for` - {HelpSetFor}\n"
+        + $"`/set-for` - {ConfigCommands.HelpSetFor}\n"
-        + $"`/remove-for` - {HelpRemoveFor}";
+        + $"`/remove-for` - {ConfigCommands.HelpRemoveFor}";
 
     #region Help strings
     const string HelpHelp = "Displays a list of available bot commands.";
     const string HelpList = "Shows the current time for all recently active known users.";
     const string HelpSet = "Adds or updates your time zone to the bot.";
-    const string HelpSetFor = "Sets/updates time zone for a given user.";
     const string HelpRemove = "Removes your time zone information from this bot.";
-    const string HelpRemoveFor = "Removes time zone for a given user.";
+    
     #endregion
 
     [SlashCommand("help", HelpHelp)]
@@ -46,8 +45,8 @@ public class UserCommands : CommandsBase {
         ).Build());
     }
 
-    [RequireGuildContext]
     [SlashCommand("list", HelpList)]
+    [EnabledInDm(false)]
     public async Task CmdList([Summary(description: "A specific user whose time to look up.")]SocketGuildUser? user = null) {
         if (!await AreUsersDownloadedAsync(Context.Guild)) {
             await RespondAsync(ErrNoUserCache, ephemeral: true);
@@ -149,6 +148,7 @@ public class UserCommands : CommandsBase {
     }
 
     [SlashCommand("set", HelpSet)]
+    [EnabledInDm(false)]
     public async Task CmdSet([Summary(description: "The new time zone to set.")]string zone) {
         var parsedzone = ParseTimeZone(zone);
         if (parsedzone == null) {
@@ -160,48 +160,12 @@ public class UserCommands : CommandsBase {
         await RespondAsync($":white_check_mark: Your time zone has been set to **{parsedzone}**.");
     }
 
-    [RequireGuildContext]
-    [SlashCommand("set-for", HelpSetFor)]
-    public async Task CmdSetFor([Summary(description: "The user whose time zone to modify.")] SocketGuildUser user,
-                                 [Summary(description: "The new time zone to set.")] string zone) {
-        if (!IsUserAdmin((SocketGuildUser)Context.User)) {
-            await RespondAsync(ErrNotAllowed, ephemeral: true).ConfigureAwait(false);
-            return;
-        }
-
-        // Extract parameters
-        var newtz = ParseTimeZone(zone);
-        if (newtz == null) {
-            await RespondAsync(ErrInvalidZone);
-            return;
-        }
-
-        using var db = DbContext;
-        db.UpdateUser(user, newtz);
-        await RespondAsync($":white_check_mark: Time zone for **{user}** set to **{newtz}**.");
-    }
-
-    [RequireGuildContext]
     [SlashCommand("remove", HelpRemove)]
+    [EnabledInDm(false)]
     public async Task CmdRemove() {
         using var db = DbContext;
         var success = db.DeleteUser((SocketGuildUser)Context.User);
         if (success) await RespondAsync(":white_check_mark: Your zone has been removed.");
         else await RespondAsync(":x: You don't have a time zone set.");
     }
-
-    [RequireGuildContext]
-    [SlashCommand("remove-for", HelpRemoveFor)]
-    public async Task CmdRemoveFor([Summary(description: "The user whose time zone to remove.")] SocketGuildUser user) {
-        if (!IsUserAdmin((SocketGuildUser)Context.User)) {
-            await RespondAsync(ErrNotAllowed, ephemeral: true).ConfigureAwait(false);
-            return;
-        }
-
-        using var db = DbContext;
-        if (db.DeleteUser(user))
-            await RespondAsync($":white_check_mark: Removed zone information for {user}.");
-        else
-            await RespondAsync($":white_check_mark: No time zone is set for {user}.");
-    }
 }

WorldTime.cs

@@ -199,21 +199,12 @@ internal class WorldTime : IDisposable {
             // Additional log information with error detail
             logresult += " " + Enum.GetName(typeof(InteractionCommandError), result.Error) + ": " + result.ErrorReason;
 
-            // Specific responses to errors, if necessary
-            if (result.Error == InteractionCommandError.UnmetPrecondition) {
-                string errReply = result.ErrorReason switch {
-                    Commands.RequireGuildContextAttribute.Error => Commands.RequireGuildContextAttribute.Reply,
-                    _ => result.ErrorReason
-                };
-                await context.Interaction.RespondAsync(errReply, ephemeral: true);
-            } else {
             // Generic error response
             // TODO when implementing proper application error logging, see here
             var ia = context.Interaction;
             if (ia.HasResponded) await ia.ModifyOriginalResponseAsync(p => p.Content = InternalError);
             else await ia.RespondAsync(InternalError);
         }
-        }
 
         Program.Log("Command", logresult);
     }