Use discordgo's permission calculator

discord.go

@@ -1,29 +1,23 @@
 package main
 
 import (
-	"encoding/json"
 	"errors"
 
 	"github.com/bwmarrin/discordgo"
 )
 
-func ptrBool(val bool) *bool {
-	return &val
-}
-
 func (user *User) channelIsBridgeable(channel *discordgo.Channel) bool {
 	switch channel.Type {
 	case discordgo.ChannelTypeGuildText, discordgo.ChannelTypeGuildNews:
 		// allowed
+	case discordgo.ChannelTypeDM, discordgo.ChannelTypeGroupDM:
+		// DMs are always bridgeable, no need for permission checks
+		return true
 	default:
 		// everything else is not allowed
 		return false
 	}
 
-	hasRole := map[string]bool{
-		channel.GuildID: true,
-	}
-	var roles []string
 	member, err := user.Session.State.Member(channel.GuildID, user.DiscordID)
 	if errors.Is(err, discordgo.ErrStateNotFound) {
 		user.log.Debugfln("Fetching own membership in %s to check own roles", channel.GuildID)
@@ -39,37 +33,15 @@ func (user *User) channelIsBridgeable(channel *discordgo.Channel) bool {
 	} else if err != nil {
 		user.log.Warnfln("Failed to get own membership in %s from cache to determine own roles for bridging %s: %v", channel.GuildID, channel.ID, err)
 	}
-	if member != nil {
+	err = user.Session.State.ChannelAdd(channel)
-		roles = member.Roles
+	if err != nil {
-		for _, role := range member.Roles {
+		user.log.Warnfln("Failed to add channel %s/%s to cache: %v", channel.GuildID, channel.ID, err)
-			hasRole[role] = true
-		}
 	}
-	var userAllowed, roleAllowed *bool
+	perms, err := user.Session.State.UserChannelPermissions(user.DiscordID, channel.ID)
-	for _, override := range channel.PermissionOverwrites {
+	if err != nil {
-		if override.Type == discordgo.PermissionOverwriteTypeMember && override.ID == user.DiscordID {
+		user.log.Warnfln("Failed to get permissions in %s/%s to determine if it's bridgeable: %v", channel.GuildID, channel.ID, err)
-			if override.Allow&discordgo.PermissionViewChannel > 0 {
+		return true
-				userAllowed = ptrBool(true)
-			} else if override.Deny&discordgo.PermissionViewChannel > 0 {
-				userAllowed = ptrBool(false)
-			}
-		} else if override.Type == discordgo.PermissionOverwriteTypeRole && hasRole[override.ID] {
-			if override.Allow&discordgo.PermissionViewChannel > 0 {
-				roleAllowed = ptrBool(true)
-			} else if override.Deny&discordgo.PermissionViewChannel > 0 {
-				roleAllowed = ptrBool(false)
-			}
-		}
 	}
-	allowed := true
+	user.log.Debugfln("Computed permissions in %s/%s: %d (view channel: %t)", channel.GuildID, channel.ID, perms, perms&discordgo.PermissionViewChannel > 0)
-	if userAllowed != nil {
+	return perms&discordgo.PermissionViewChannel > 0
-		allowed = *userAllowed
-	} else if roleAllowed != nil {
-		allowed = *roleAllowed
-	}
-	if !allowed {
-		dat, _ := json.Marshal(channel.PermissionOverwrites)
-		user.log.Debugfln("Permission overwrites (%s) resulted in %s/%s not being allowed to bridge with roles %+v", dat, channel.GuildID, channel.ID, roles)
-	}
-	return allowed
 }

go.mod

@@ -34,4 +34,4 @@ require (
 	maunium.net/go/mauflag v1.0.0 // indirect
 )
 
-replace github.com/bwmarrin/discordgo => github.com/beeper/discordgo v0.0.0-20230129113304-139f45f429a0
+replace github.com/bwmarrin/discordgo => github.com/beeper/discordgo v0.0.0-20230129125832-37978ff8e399

go.sum

@@ -1,6 +1,6 @@
 github.com/DATA-DOG/go-sqlmock v1.5.0 h1:Shsta01QNfFxHCfpW6YH2STWB0MudeXXEWMr20OEh60=
-github.com/beeper/discordgo v0.0.0-20230129113304-139f45f429a0 h1:RrF9ffkMyEsUtZqWR/m/KXSrYbpyT7bkuL+KY8pexSE=
+github.com/beeper/discordgo v0.0.0-20230129125832-37978ff8e399 h1:3GZhhiyeXo/r40NmaQddBpCfosSSIrSrqZBLXJWrtYc=
-github.com/beeper/discordgo v0.0.0-20230129113304-139f45f429a0/go.mod h1:NJZpH+1AfhIcyQsPeuBKsUtYrRnjkyu0kIVMCHkZtRY=
+github.com/beeper/discordgo v0.0.0-20230129125832-37978ff8e399/go.mod h1:NJZpH+1AfhIcyQsPeuBKsUtYrRnjkyu0kIVMCHkZtRY=
 github.com/coreos/go-systemd/v22 v22.3.3-0.20220203105225-a9a7ef127534/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=