update

src/modules/rest/api/attachment.rs

@@ -29,11 +29,11 @@ use crate::modules::rest::ErrorCode;
 use crate::modules::store::tantivy::attachment::ATTACHMENT_MANAGER;
 use crate::modules::store::tantivy::model::AttachmentModel;
 use crate::modules::users::permissions::Permission;
-use crate::modules::utils::validate_tag;
 use crate::raise_error;
 use poem_openapi::param::Path;
 use poem_openapi::payload::Json;
 use poem_openapi::OpenApi;
+use tantivy::schema::Facet;
 use std::collections::HashSet;
 
 pub struct AttachmentApi;
@@ -133,8 +133,8 @@ impl AttachmentApi {
     ) -> ApiResult<()> {
         let req = req.0;
         for tag in &req.tags {
-            validate_tag(tag)
-                .map_err(|e| raise_error!(format!("{}", e), ErrorCode::InvalidParameter))?;
+            Facet::from_text(tag)
+                .map_err(|e| raise_error!(format!("{:#?}", e), ErrorCode::InvalidParameter))?;
         }
 
         for account_id in req.updates.keys() {

src/modules/rest/api/message.rs

@@ -38,12 +38,12 @@ use crate::modules::store::envelope::Envelope;
 use crate::modules::store::storage::get_reader;
 use crate::modules::store::tantivy::envelope::ENVELOPE_MANAGER;
 use crate::modules::users::permissions::Permission;
-use crate::modules::utils::validate_tag;
 use crate::raise_error;
 use poem::Body;
 use poem_openapi::param::{Path, Query};
 use poem_openapi::payload::{Attachment, AttachmentType, Json};
 use poem_openapi::OpenApi;
+use tantivy::schema::Facet;
 use std::collections::HashMap;
 use std::collections::HashSet;
 
@@ -350,8 +350,8 @@ impl MessageApi {
     ) -> ApiResult<()> {
         let req = req.0;
         for tag in &req.tags {
-            validate_tag(tag)
-                .map_err(|e| raise_error!(format!("{}", e), ErrorCode::InvalidParameter))?;
+            Facet::from_text(tag)
+                .map_err(|e| raise_error!(format!("{:#?}", e), ErrorCode::InvalidParameter))?;
         }
 
         for account_id in req.updates.keys() {

src/modules/store/tantivy/model.rs

@@ -1,7 +1,28 @@
+//
+// Copyright (c) 2025-2026 rustmailer.com (https://rustmailer.com)
+//
+// This file is part of the Bichon Email Archiving Project
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
 use poem_openapi::Object;
 use serde::{Deserialize, Serialize};
 use std::collections::HashSet;
-use tantivy::{schema::Value, TantivyDocument};
+use tantivy::{
+    schema::{Facet, Value},
+    TantivyDocument,
+};
 
 use crate::{
     modules::{
@@ -107,7 +128,12 @@ impl EnvelopeWithAttachments {
         let tags: Vec<String> = doc
             .get_all(fields.f_tags)
             .filter_map(|value| value.as_facet())
-            .map(|f| f.to_string())
+            .map(|facet_encoded_str| {
+                Facet::from_encoded(facet_encoded_str.as_bytes().to_vec())
+                    .ok()
+                    .map(|facet| facet.to_string())
+            })
+            .flatten()
             .collect();
 
         let account_id = extract_u64_field(doc, fields.f_account_id, F_ACCOUNT_ID)?;
@@ -361,14 +387,25 @@ impl AttachmentModel {
         let tags: Vec<String> = doc
             .get_all(f.f_tags)
             .filter_map(|value| value.as_facet())
-            .map(|f| f.to_string())
+            .map(|facet_encoded_str| {
+                Facet::from_encoded(facet_encoded_str.as_bytes().to_vec())
+                    .ok()
+                    .map(|facet| facet.to_string())
+            })
+            .flatten()
             .collect();
 
         let auto_tags: Vec<String> = doc
             .get_all(f.f_auto_tags)
             .filter_map(|value| value.as_facet())
-            .map(|f| f.to_string())
+            .map(|facet_encoded_str| {
+                Facet::from_encoded(facet_encoded_str.as_bytes().to_vec())
+                    .ok()
+                    .map(|facet| facet.to_string())
+            })
+            .flatten()
             .collect();
+
         let account_id = extract_u64_field(doc, f.f_account_id, F_ACCOUNT_ID)?;
         let mailbox_id = extract_u64_field(doc, f.f_mailbox_id, F_MAILBOX_ID)?;
         let account = AccountModel::get(account_id)?;

src/modules/utils/mod.rs

@@ -347,31 +347,6 @@ pub fn decode_avatar_bytes(base64_str: &str) -> BichonResult<Vec<u8>> {
     Ok(bytes)
 }
 
-pub fn validate_tag(tag: &str) -> Result<(), String> {
-    if tag.is_empty() {
-        return Err("Tag cannot be empty".to_string());
-    }
-
-    const INVALID: &[char] = &[
-        '\'', '"', '`', ';', ',', '(', ')', '[', ']', '{', '}', '<', '>',
-    ];
-
-    let mut found = Vec::new();
-
-    for c in tag.chars() {
-        if INVALID.contains(&c) && !found.contains(&c) {
-            found.push(c);
-        }
-    }
-
-    if !found.is_empty() {
-        let chars: String = found.iter().collect();
-        return Err(format!("Tag contains invalid characters: {}", chars));
-    }
-
-    Ok(())
-}
-
 pub fn compute_content_hash(content: &[u8]) -> String {
     let hash = blake3::hash(content);
     hash.to_hex().to_string()

web/src/features/search/mail-list-table.tsx

@@ -173,7 +173,28 @@ export function MailListTable({
     {
       accessorKey: "subject",
       header: t('search.subject'),
-      cell: ({ row }) => <LongText className='text-xs'>{row.original.subject}</LongText>,
+      cell: ({ row }) => {
+        const tags = row.original.tags ?? [];
+        return (
+          <div className="flex flex-col gap-1 py-1.5 min-w-0">
+            <LongText className='text-xs font-medium truncate'>
+              {row.original.subject}
+            </LongText>
+            {tags.length > 0 && (
+              <div className="flex items-center gap-1 flex-wrap">
+                {tags.map((tag) => (
+                  <span
+                    key={tag}
+                    className="inline-flex items-center rounded-md bg-primary/15 px-2 py-0.5 text-[10px] font-semibold text-primary ring-1 ring-inset ring-primary/20"
+                  >
+                    {tag}
+                  </span>
+                ))}
+              </div>
+            )}
+          </div>
+        );
+      },
       meta: { className: 'text-left text-xs' }
     },
     {

web/src/lib/utils.ts

@@ -88,12 +88,28 @@ export function validateTag(facetPath: string) {
     };
   }
 
-  const invalidChars = /['"`;,()[\]{}<>]/;
-
-  if (invalidChars.test(facetPath)) {
+  if (!facetPath.startsWith('/')) {
     return {
       valid: false,
-      error: "Tag path contains invalid characters"
+      error: "Tag path must start with '/'"
+    };
+  }
+
+  let escaped = false;
+  for (let i = 1; i < facetPath.length; i++) {
+    const char = facetPath[i];
+
+    if (escaped) {
+      escaped = false;
+    } else if (char === '\\') {
+      escaped = true;
+    }
+  }
+
+  if (escaped) {
+    return {
+      valid: false,
+      error: "Tag path has unmatched escape character at the end"
     };
   }
 
@@ -101,6 +117,7 @@ export function validateTag(facetPath: string) {
 }
 
 
+
 export function formatTimestamp(milliseconds: number): string {
   const date = new Date(milliseconds);
   const year = date.getFullYear();