Remove CommandError, return error embeds instead

src/pluralkit/bot/commands/__init__.py

@@ -6,7 +6,7 @@ import discord
 
 import pluralkit
 from pluralkit import db
-from pluralkit.bot import utils
+from pluralkit.bot import utils, embeds
 
 logger = logging.getLogger("pluralkit.bot.commands")
 
@@ -17,10 +17,6 @@ class InvalidCommandSyntax(Exception):
 
 class NoSystemRegistered(Exception):
     pass
-    
-class CommandError(Exception):
-    def __init__(self, message):
-        self.message = message
 
 class CommandContext(namedtuple("CommandContext", ["client", "conn", "message", "system"])):
     client: discord.Client
@@ -62,9 +58,6 @@ def command(cmd, usage=None, description=None, category=None, system_required=Tr
             except InvalidCommandSyntax:
                 usage_str = "**Usage:** pk;{} {}".format(cmd, usage or "")
                 await client.send_message(message.channel, embed=utils.make_default_embed(usage_str))
-            except CommandError as e:
-                embed = e.message if isinstance(e.message, discord.Embed) else utils.make_error_embed(e.message)
-                await client.send_message(message.channel, embed=embed)
             except Exception:
                 logger.exception("Exception while handling command {} (args={}, system={})".format(cmd, args, system.hid if system else "(none)"))
 
@@ -86,7 +79,7 @@ def member_command(cmd, usage=None, description=None, category=None, system_only
             member = await utils.get_member_fuzzy(ctx.conn, system_id=system_id, key=args[0], system_only=system_only)
 
             if member is None:
-                raise CommandError("Can't find member \"{}\".".format(args[0]))
+                return embeds.error("Can't find member \"{}\".".format(args[0]))
 
             ctx = MemberCommandContext(client=ctx.client, conn=ctx.conn, message=ctx.message, system=ctx.system, member=member)
             return await func(ctx, args[1:])

src/pluralkit/bot/commands/import_commands.py

@@ -1,10 +1,8 @@
 import asyncio
 import re
 from datetime import datetime
-import logging
 from typing import List
 
-from pluralkit.bot import utils
 from pluralkit.bot.commands import *
 
 logger = logging.getLogger("pluralkit.commands")
@@ -16,7 +14,7 @@ async def import_tupperware(ctx: CommandContext, args: List[str]):
 
     # Check if there's any Tupperware bot on the server
     if not tupperware_members:
-        raise CommandError("This command only works in a server where the Tupperware bot is also present.")
+        return embeds.error("This command only works in a server where the Tupperware bot is also present.")
 
     # Make sure at least one of the bts have send/read permissions here
     for bot_member in tupperware_members:
@@ -26,7 +24,7 @@ async def import_tupperware(ctx: CommandContext, args: List[str]):
             break
     else:
         # If no bots have permission (ie. loop doesn't break), throw error
-        raise CommandError("This command only works in a channel where the Tupperware bot has read/send access.")
+        return embeds.error("This command only works in a channel where the Tupperware bot has read/send access.")
 
     await ctx.reply(embed=utils.make_default_embed("Please reply to this message with `tul!list` (or the server equivalent)."))
     
@@ -43,12 +41,12 @@ async def import_tupperware(ctx: CommandContext, args: List[str]):
         
         return tw_msg.embeds[0]["title"].startswith("{}#{}".format(ctx.message.author.name, ctx.message.author.discriminator))
 
-    embeds = []
+    tupperware_page_embeds = []
     
     tw_msg: discord.Message = await ctx.client.wait_for_message(channel=ctx.message.channel, timeout=60.0, check=ensure_account)
     if not tw_msg:
-        raise CommandError("Tupperware import timed out.")
+        return embeds.error("Tupperware import timed out.")
-    embeds.append(tw_msg.embeds[0])
+    tupperware_page_embeds.append(tw_msg.embeds[0])
 
     # Handle Tupperware pagination
     def match_pagination():
@@ -84,11 +82,11 @@ async def import_tupperware(ctx: CommandContext, args: List[str]):
 
             # Make sure it doesn't spin here for too long, time out after 30 seconds since last new page
             if (datetime.utcnow() - last_found_time).seconds > 30:
-                raise CommandError("Pagination scan timed out.")
+                return embeds.error("Pagination scan timed out.")
 
         # Now that we've got all the pages, put them in the embeds list
         # Make sure to erase the original one we put in above too
-        embeds = list([embed for page, embed in sorted(pages_found.items(), key=lambda x: x[0])])
+        tupperware_page_embeds = list([embed for page, embed in sorted(pages_found.items(), key=lambda x: x[0])])
 
         # Also edit the status message to indicate we're now importing, and it may take a while because there's probably a lot of members
         await ctx.client.edit_message(status_msg, "All pages read. Now importing...")
@@ -103,7 +101,7 @@ async def import_tupperware(ctx: CommandContext, args: List[str]):
         system = await db.create_system(ctx.conn, system_name=None, system_hid=hid)
         await db.link_account(ctx.conn, system_id=system.id, account_id=ctx.message.author.id)
 
-    for embed in embeds:
+    for embed in tupperware_page_embeds:
         for field in embed["fields"]:
             name = field["name"]
             lines = field["value"].split("\n")
@@ -150,4 +148,4 @@ async def import_tupperware(ctx: CommandContext, args: List[str]):
             await db.update_member_field(ctx.conn, member_id=existing_member.id, field="birthday", value=member_birthdate)
             await db.update_member_field(ctx.conn, member_id=existing_member.id, field="description", value=member_description)
     
-    return "System information imported. Try using `pk;system` now.\nYou should probably remove your members from Tupperware to avoid double-posting."
+    return embeds.success("System information imported. Try using `pk;system` now.\nYou should probably remove your members from Tupperware to avoid double-posting.")

src/pluralkit/bot/commands/member_commands.py

@@ -4,7 +4,7 @@ from datetime import datetime
 from typing import List
 from urllib.parse import urlparse
 
-from pluralkit.bot import utils
+from pluralkit.bot import utils, embeds
 from pluralkit.bot.commands import *
 
 logger = logging.getLogger("pluralkit.commands")
@@ -21,14 +21,14 @@ async def new_member(ctx: MemberCommandContext, args: List[str]):
     name = " ".join(args)
     bounds_error = utils.bounds_check_member_name(name, ctx.system.tag)
     if bounds_error:
-        raise CommandError(bounds_error)
+        return embeds.error(bounds_error)
 
     # TODO: figure out what to do if this errors out on collision on generate_hid
     hid = utils.generate_hid()
 
     # Insert member row
     await db.create_member(ctx.conn, system_id=ctx.system.id, member_name=name, member_hid=hid)
-    return "Member \"{}\" (`{}`) registered!".format(name, hid)
+    return embeds.success("Member \"{}\" (`{}`) registered!".format(name, hid))
 
 
 @member_command(cmd="member set", usage="<name|description|color|pronouns|birthdate|avatar> [value]", description="Edits a member property. Leave [value] blank to clear.", category="Member commands")
@@ -48,7 +48,7 @@ async def member_set(ctx: MemberCommandContext, args: List[str]):
 
     prop = args[0]
     if prop not in allowed_properties:
-        raise CommandError("Unknown property {}. Allowed properties are {}.".format(prop, ", ".join(allowed_properties)))
+        return embeds.error("Unknown property {}. Allowed properties are {}.".format(prop, ", ".join(allowed_properties)))
 
     if len(args) >= 2:
         value = " ".join(args[1:])
@@ -57,12 +57,12 @@ async def member_set(ctx: MemberCommandContext, args: List[str]):
         if prop == "name":
             bounds_error = utils.bounds_check_member_name(value, ctx.system.tag)
             if bounds_error:
-                raise CommandError(bounds_error)
+                return embeds.error(bounds_error)
 
         if prop == "color":
             match = re.fullmatch("#?([0-9A-Fa-f]{6})", value)
             if not match:
-                raise CommandError("Color must be a valid hex color (eg. #ff0000)")
+                return embeds.error("Color must be a valid hex color (eg. #ff0000)")
 
             value = match.group(1).lower()
         
@@ -76,7 +76,7 @@ async def member_set(ctx: MemberCommandContext, args: List[str]):
                     # Useful if you want your birthday to be displayed yearless.
                     value = datetime.strptime("0001-" + value, "%Y-%m-%d").date()
                 except ValueError:
-                    raise CommandError("Invalid date. Date must be in ISO-8601 format (eg. 1999-07-25).")
+                    return embeds.error("Invalid date. Date must be in ISO-8601 format (eg. 1999-07-25).")
 
         if prop == "avatar":
             user = await utils.parse_mention(ctx.client, value)
@@ -90,11 +90,11 @@ async def member_set(ctx: MemberCommandContext, args: List[str]):
                 if u.scheme in ["http", "https"] and u.netloc and u.path:
                     value = value
                 else:
-                    raise CommandError("Invalid URL.")
+                    return embeds.error("Invalid URL.")
     else:
         # Can't clear member name
         if prop == "name":
-            raise CommandError("Can't clear member name.")
+            return embeds.error("Can't clear member name.")
 
         # Clear from DB
         value = None
@@ -102,7 +102,7 @@ async def member_set(ctx: MemberCommandContext, args: List[str]):
     db_prop = db_properties[prop]
     await db.update_member_field(ctx.conn, member_id=ctx.member.id, field=db_prop, value=value)
     
-    response = utils.make_default_embed("{} {}'s {}.".format("Updated" if value else "Cleared", ctx.member.name, prop))
+    response = embeds.success("{} {}'s {}.".format("Updated" if value else "Cleared", ctx.member.name, prop))
     if prop == "avatar" and value:
         response.set_image(url=value)
     if prop == "color" and value:
@@ -117,10 +117,10 @@ async def member_proxy(ctx: MemberCommandContext, args: List[str]):
         # Sanity checking
         example = " ".join(args)
         if "text" not in example:
-            raise CommandError("Example proxy message must contain the string 'text'.")
+            return embeds.error("Example proxy message must contain the string 'text'.")
 
         if example.count("text") != 1:
-            raise CommandError("Example proxy message must contain the string 'text' exactly once.")
+            return embeds.error("Example proxy message must contain the string 'text' exactly once.")
 
         # Extract prefix and suffix
         prefix = example[:example.index("text")].strip()
@@ -136,7 +136,7 @@ async def member_proxy(ctx: MemberCommandContext, args: List[str]):
     async with ctx.conn.transaction():
         await db.update_member_field(ctx.conn, member_id=ctx.member.id, field="prefix", value=prefix)
         await db.update_member_field(ctx.conn, member_id=ctx.member.id, field="suffix", value=suffix)
-        return "Proxy settings updated." if prefix or suffix else "Proxy settings cleared."
+        return embeds.success("Proxy settings updated." if prefix or suffix else "Proxy settings cleared.")
 
 @member_command("member delete", description="Deletes a member from your system ***permanently***.", category="Member commands")
 async def member_delete(ctx: MemberCommandContext, args: List[str]):
@@ -145,6 +145,6 @@ async def member_delete(ctx: MemberCommandContext, args: List[str]):
     msg = await ctx.client.wait_for_message(author=ctx.message.author, channel=ctx.message.channel, timeout=60.0)
     if msg and msg.content.lower() == ctx.member.hid.lower():
         await db.delete_member(ctx.conn, member_id=ctx.member.id)
-        return "Member deleted."
+        return embeds.success("Member deleted.")
     else:
-        return "Member deletion cancelled."
+        return embeds.success("Member deletion cancelled.")

src/pluralkit/bot/commands/message_commands.py

@@ -1,7 +1,7 @@
 import logging
 from typing import List
 
-from pluralkit.bot import utils
+from pluralkit.bot import utils, embeds
 from pluralkit.bot.commands import *
 
 logger = logging.getLogger("pluralkit.commands")
@@ -21,7 +21,7 @@ async def message_info(ctx: CommandContext, args: List[str]):
     # Find the message in the DB
     message = await db.get_message(ctx.conn, str(mid))
     if not message:
-        raise CommandError("Message not found.")
+        raise embeds.error("Message with ID '{}' not found.".format(args[0]))
 
     # Get the original sender of the messages
     try:

src/pluralkit/bot/commands/misc_commands.py

@@ -7,7 +7,7 @@ from typing import List
 from discord.utils import oauth_url
 
 import pluralkit.utils
-from pluralkit.bot import utils
+from pluralkit.bot import utils, embeds
 from pluralkit.bot.commands import *
 
 logger = logging.getLogger("pluralkit.commands")
@@ -47,7 +47,7 @@ async def invite_link(ctx: CommandContext, args: List[str]):
 
     url = oauth_url(client_id, permissions)
     logger.debug("Sending invite URL: {}".format(url))
-    return url
+    return embeds.success("Use this link to add PluralKit to your server: {}".format(url))
 
 @command(cmd="export", description="Exports system data to a machine-readable format.")
 async def export(ctx: CommandContext, args: List[str]):

src/pluralkit/bot/commands/mod_commands.py

@@ -1,7 +1,7 @@
 import logging
 from typing import List
 
-from pluralkit.bot import utils
+from pluralkit.bot import utils, embeds
 from pluralkit.bot.commands import *
 
 logger = logging.getLogger("pluralkit.commands")
@@ -9,7 +9,7 @@ logger = logging.getLogger("pluralkit.commands")
 @command(cmd="mod log", usage="[channel]", description="Sets the bot to log events to a specified channel. Leave blank to disable.", category="Moderation commands", system_required=False)
 async def set_log(ctx: CommandContext, args: List[str]):
     if not ctx.message.author.server_permissions.administrator:
-        raise CommandError("You must be a server administrator to use this command.")
+        return embeds.error("You must be a server administrator to use this command.")
     
     server = ctx.message.server
     if len(args) == 0:
@@ -17,8 +17,8 @@ async def set_log(ctx: CommandContext, args: List[str]):
     else:
         channel = utils.parse_channel_mention(args[0], server=server)
         if not channel:
-            raise CommandError("Channel not found.")
+            return embeds.error("Channel not found.")
         channel_id = channel.id
 
     await db.update_server(ctx.conn, server.id, logging_channel_id=channel_id)
-    return "Updated logging channel." if channel_id else "Cleared logging channel."
+    return embeds.success("Updated logging channel." if channel_id else "Cleared logging channel.")

src/pluralkit/bot/commands/switch_commands.py

@@ -7,7 +7,7 @@ import humanize
 
 import pluralkit.utils
 from pluralkit import Member
-from pluralkit.bot import utils
+from pluralkit.bot import utils, embeds
 from pluralkit.bot.commands import *
 
 logger = logging.getLogger("pluralkit.commands")
@@ -22,7 +22,7 @@ async def switch_member(ctx: MemberCommandContext, args: List[str]):
         # Find the member
         member = await utils.get_member_fuzzy(ctx.conn, ctx.system.id, member_name)
         if not member:
-            raise CommandError("Couldn't find member \"{}\".".format(member_name))
+            return embeds.error("Couldn't find member \"{}\".".format(member_name))
         members.append(member)
 
     # Compare requested switch IDs and existing fronter IDs to check for existing switches
@@ -31,12 +31,12 @@ async def switch_member(ctx: MemberCommandContext, args: List[str]):
     fronter_ids = (await pluralkit.utils.get_fronter_ids(ctx.conn, ctx.system.id))[0]
     if member_ids == fronter_ids:
         if len(members) == 1:
-            raise CommandError("{} is already fronting.".format(members[0].name))
+            return embeds.error("{} is already fronting.".format(members[0].name))
-        raise CommandError("Members {} are already fronting.".format(", ".join([m.name for m in members])))
+        return embeds.error("Members {} are already fronting.".format(", ".join([m.name for m in members])))
 
     # Also make sure there aren't any duplicates
     if len(set(member_ids)) != len(member_ids):
-        raise CommandError("Duplicate members in switch list.")
+        return embeds.error("Duplicate members in switch list.")
 
     # Log the switch
     async with ctx.conn.transaction():
@@ -45,20 +45,20 @@ async def switch_member(ctx: MemberCommandContext, args: List[str]):
             await db.add_switch_member(ctx.conn, switch_id=switch_id, member_id=member.id)
 
     if len(members) == 1:
-        return "Switch registered. Current fronter is now {}.".format(members[0].name)
+        return embeds.success("Switch registered. Current fronter is now {}.".format(members[0].name))
     else:
-        return "Switch registered. Current fronters are now {}.".format(", ".join([m.name for m in members]))
+        return embeds.success("Switch registered. Current fronters are now {}.".format(", ".join([m.name for m in members])))
 
 @command(cmd="switch out", description="Registers a switch with no one in front.", category="Switching commands")
 async def switch_out(ctx: MemberCommandContext, args: List[str]):
     # Get current fronters
     fronters, _ = await pluralkit.utils.get_fronter_ids(ctx.conn, system_id=ctx.system.id)
     if not fronters:
-        raise CommandError("There's already no one in front.")
+        raise embeds.error("There's already no one in front.")
 
     # Log it, and don't log any members
     await db.add_switch(ctx.conn, system_id=ctx.system.id)
-    return "Switch-out registered."
+    return embeds.success("Switch-out registered.")
 
 @command(cmd="switch move", usage="<time>", description="Moves the most recent switch to a different point in time.", category="Switching commands")
 async def switch_move(ctx: MemberCommandContext, args: List[str]):
@@ -71,18 +71,18 @@ async def switch_move(ctx: MemberCommandContext, args: List[str]):
         "RETURN_AS_TIMEZONE_AWARE": False
     })
     if not new_time:
-        raise CommandError("{} can't be parsed as a valid time.".format(" ".join(args)))
+        return embeds.error("{} can't be parsed as a valid time.".format(" ".join(args)))
 
     # Make sure the time isn't in the future
     if new_time > datetime.now():
-        raise CommandError("Can't move switch to a time in the future.")
+        return embeds.error("Can't move switch to a time in the future.")
 
     # Make sure it all runs in a big transaction for atomicity
     async with ctx.conn.transaction():
         # Get the last two switches to make sure the switch to move isn't before the second-last switch
         last_two_switches = await pluralkit.utils.get_front_history(ctx.conn, ctx.system.id, count=2)
         if len(last_two_switches) == 0:
-            raise CommandError("There are no registered switches for this system.")
+            return embeds.error("There are no registered switches for this system.")
 
         last_timestamp, last_fronters = last_two_switches[0]
         if len(last_two_switches) > 1:
@@ -90,7 +90,7 @@ async def switch_move(ctx: MemberCommandContext, args: List[str]):
 
             if new_time < second_last_timestamp:
                 time_str = humanize.naturaltime(second_last_timestamp)
-                raise CommandError("Can't move switch to before last switch time ({}), as it would cause conflicts.".format(time_str))
+                return embeds.error("Can't move switch to before last switch time ({}), as it would cause conflicts.".format(time_str))
         
         # Display the confirmation message w/ humanized times
         members = ", ".join([member.name for member in last_fronters]) or "nobody"
@@ -107,14 +107,14 @@ async def switch_move(ctx: MemberCommandContext, args: List[str]):
 
         reaction = await ctx.client.wait_for_reaction(emoji=["✅", "❌"], message=confirm_msg, user=ctx.message.author, timeout=60.0)
         if not reaction:
-            raise CommandError("Switch move timed out.")
+            return embeds.error("Switch move timed out.")
 
         if reaction.reaction.emoji == "❌":
-            raise CommandError("Switch move cancelled.")
+            return embeds.error("Switch move cancelled.")
 
         # DB requires the actual switch ID which our utility method above doesn't return, do this manually
         switch_id = (await db.front_history(ctx.conn, ctx.system.id, count=1))[0]["id"]
 
         # Change the switch in the DB
         await db.move_last_switch(ctx.conn, ctx.system.id, switch_id, new_time)
-        return "Switch moved."
+        return embeds.success("Switch moved.")

src/pluralkit/bot/commands/system_commands.py

@@ -6,6 +6,7 @@ import dateparser
 import humanize
 
 import pluralkit.utils
+from pluralkit.bot import embeds
 from pluralkit.bot.commands import *
 
 logger = logging.getLogger("pluralkit.commands")
@@ -21,14 +22,14 @@ async def system_info(ctx: CommandContext, args: List[str]):
         system = await utils.get_system_fuzzy(ctx.conn, ctx.client, args[0])
 
         if system is None:
-            raise CommandError("Unable to find system \"{}\".".format(args[0]))
+            return embeds.error("Unable to find system \"{}\".".format(args[0]))
 
     await ctx.reply(embed=await utils.generate_system_info_card(ctx.conn, ctx.client, system))
 
 @command(cmd="system new", usage="[name]", description="Registers a new system to this account.", category="System commands", system_required=False)
 async def new_system(ctx: CommandContext, args: List[str]):
     if ctx.system:
-        raise CommandError("You already have a system registered. To delete your system, use `pk;system delete`, or to unlink your system from this account, use `pk;system unlink`.")
+        return embeds.error("You already have a system registered. To delete your system, use `pk;system delete`, or to unlink your system from this account, use `pk;system unlink`.")
 
     system_name = None
     if len(args) > 0:
@@ -42,7 +43,7 @@ async def new_system(ctx: CommandContext, args: List[str]):
 
         # Link account
         await db.link_account(ctx.conn, system_id=system.id, account_id=ctx.message.author.id)
-        return "System registered! To begin adding members, use `pk;member new <name>`."
+        return embeds.success("System registered! To begin adding members, use `pk;member new <name>`.")
 
 @command(cmd="system set", usage="<name|description|tag|avatar> [value]", description="Edits a system property. Leave [value] blank to clear.", category="System commands")
 async def system_set(ctx: CommandContext, args: List[str]):
@@ -59,14 +60,14 @@ async def system_set(ctx: CommandContext, args: List[str]):
 
     prop = args[0]
     if prop not in allowed_properties:
-        raise CommandError("Unknown property {}. Allowed properties are {}.".format(prop, ", ".join(allowed_properties)))
+        raise embeds.error("Unknown property {}. Allowed properties are {}.".format(prop, ", ".join(allowed_properties)))
 
     if len(args) >= 2:
         value = " ".join(args[1:])
         # Sanity checking
         if prop == "tag":
             if len(value) > 32:
-                raise CommandError("Can't have system tag longer than 32 characters.")
+                raise embeds.error("Can't have system tag longer than 32 characters.")
 
             # Make sure there are no members which would make the combined length exceed 32
             members_exceeding = await db.get_members_exceeding(ctx.conn, system_id=ctx.system.id, length=32 - len(value) - 1)
@@ -75,7 +76,7 @@ async def system_set(ctx: CommandContext, args: List[str]):
                 member_names = ", ".join([member.name
                                         for member in members_exceeding])
                 logger.debug("Members exceeding combined length with tag '{}': {}".format(value, member_names))
-                raise CommandError("The maximum length of a name plus the system tag is 32 characters. The following members would exceed the limit: {}. Please reduce the length of the tag, or rename the members.".format(member_names))
+                raise embeds.error("The maximum length of a name plus the system tag is 32 characters. The following members would exceed the limit: {}. Please reduce the length of the tag, or rename the members.".format(member_names))
 
         if prop == "avatar":
             user = await utils.parse_mention(ctx.client, value)
@@ -89,7 +90,7 @@ async def system_set(ctx: CommandContext, args: List[str]):
                 if u.scheme in ["http", "https"] and u.netloc and u.path:
                     value = value
                 else:
-                    raise CommandError("Invalid URL.")
+                    raise embeds.error("Invalid URL.")
     else:
         # Clear from DB
         value = None
@@ -97,7 +98,7 @@ async def system_set(ctx: CommandContext, args: List[str]):
     db_prop = db_properties[prop]
     await db.update_system_field(ctx.conn, system_id=ctx.system.id, field=db_prop, value=value)
 
-    response = utils.make_default_embed("{} system {}.".format("Updated" if value else "Cleared", prop))
+    response = embeds.success("{} system {}.".format("Updated" if value else "Cleared", prop))
     if prop == "avatar" and value:
         response.set_image(url=value)
     return response
@@ -110,12 +111,12 @@ async def system_link(ctx: CommandContext, args: List[str]):
     # Find account to link
     linkee = await utils.parse_mention(ctx.client, args[0])
     if not linkee:
-        raise CommandError("Account not found.")
+        return embeds.error("Account not found.")
 
     # Make sure account doesn't already have a system
     account_system = await db.get_system_by_account(ctx.conn, linkee.id)
     if account_system:
-        raise CommandError("Account is already linked to a system (`{}`)".format(account_system.hid))
+        return embeds.error("Account is already linked to a system (`{}`)".format(account_system.hid))
 
     # Send confirmation message
     msg = await ctx.reply("{}, please confirm the link by clicking the ✅ reaction on this message.".format(linkee.mention))
@@ -125,22 +126,22 @@ async def system_link(ctx: CommandContext, args: List[str]):
     reaction = await ctx.client.wait_for_reaction(emoji=["✅", "❌"], message=msg, user=linkee, timeout=60.0)
     # If account to be linked confirms...
     if not reaction:
-        raise CommandError("Account link timed out.")
+        return embeds.error("Account link timed out.")
     if not reaction.reaction.emoji == "✅":
-        raise CommandError("Account link cancelled.")
+        return embeds.error("Account link cancelled.")
 
     await db.link_account(ctx.conn, system_id=ctx.system.id, account_id=linkee.id)
-    return "Account linked to system."
+    return embeds.success("Account linked to system.")
 
 @command(cmd="system unlink", description="Unlinks your system from this account. There must be at least one other account linked.", category="System commands")
 async def system_unlink(ctx: CommandContext, args: List[str]):
     # Make sure you can't unlink every account
     linked_accounts = await db.get_linked_accounts(ctx.conn, system_id=ctx.system.id)
     if len(linked_accounts) == 1:
-        raise CommandError("This is the only account on your system, so you can't unlink it.")
+        return embeds.error("This is the only account on your system, so you can't unlink it.")
 
     await db.unlink_account(ctx.conn, system_id=ctx.system.id, account_id=ctx.message.author.id)
-    return "Account unlinked."
+    return embeds.success("Account unlinked.")
 
 @command(cmd="system fronter", usage="[system]", description="Gets the current fronter(s) in the system.", category="Switching commands", system_required=False)
 async def system_fronter(ctx: CommandContext, args: List[str]):
@@ -152,7 +153,7 @@ async def system_fronter(ctx: CommandContext, args: List[str]):
         system = await utils.get_system_fuzzy(ctx.conn, ctx.client, args[0])
 
         if system is None:
-            raise CommandError("Can't find system \"{}\".".format(args[0]))
+            return embeds.error("Can't find system \"{}\".".format(args[0]))
 
     fronters, timestamp = await pluralkit.utils.get_fronters(ctx.conn, system_id=system.id)
     fronter_names = [member.name for member in fronters]
@@ -180,7 +181,7 @@ async def system_fronthistory(ctx: CommandContext, args: List[str]):
         system = await utils.get_system_fuzzy(ctx.conn, ctx.client, args[0])
 
         if system is None:
-            raise CommandError("Can't find system \"{}\".".format(args[0]))
+            raise embeds.error("Can't find system \"{}\".".format(args[0]))
 
     lines = []
     front_history = await pluralkit.utils.get_front_history(ctx.conn, system.id, count=10)
@@ -213,9 +214,9 @@ async def system_delete(ctx: CommandContext, args: List[str]):
     msg = await ctx.client.wait_for_message(author=ctx.message.author, channel=ctx.message.channel, timeout=60.0)
     if msg and msg.content.lower() == ctx.system.hid.lower():
         await db.remove_system(ctx.conn, system_id=ctx.system.id)
-        return "System deleted."
+        return embeds.success("System deleted.")
     else:
-        return "System deletion cancelled."
+        return embeds.error("System deletion cancelled.")
 
 
 @command(cmd="system frontpercent", usage="[time]",
@@ -235,7 +236,7 @@ async def system_frontpercent(ctx: CommandContext, args: List[str]):
     # Fetch list of switches
     all_switches = await pluralkit.utils.get_front_history(ctx.conn, ctx.system.id, 99999)
     if not all_switches:
-        raise CommandError("No switches registered to this system.")
+        return embeds.error("No switches registered to this system.")
 
     # Cull the switches *ending* before the limit, if given
     # We'll need to find the first switch starting before the limit, then cut off every switch *before* that
@@ -284,7 +285,7 @@ async def system_frontpercent(ctx: CommandContext, args: List[str]):
     span_start = max(start_times[-1], before) if before else start_times[-1]
     total_time = datetime.utcnow() - span_start
 
-    embed = utils.make_default_embed(None)
+    embed = embeds.status("")
     for member_id, front_time in sorted(member_times.items(), key=lambda x: x[1], reverse=True):
         member = members_by_id[member_id] if member_id else None
 

src/pluralkit/bot/embeds.py

@@ -0,0 +1,29 @@
+from typing import Tuple
+
+import discord
+
+
+def success(text: str):
+    embed = discord.Embed()
+    embed.description = text
+    embed.colour = discord.Colour.green()
+    return embed
+
+
+def error(text: str, help: Tuple[str, str] = None):
+    embed = discord.Embed()
+    embed.description = text
+    embed.colour = discord.Colour.dark_red()
+
+    if help:
+        help_title, help_text = help
+        embed.add_field(name=help_title, value=help_text)
+
+    return embed
+
+
+def status(text: str):
+    embed = discord.Embed()
+    embed.description = text
+    embed.colour = discord.Colour.blue()
+    return embed