Appwrite Dart SDK
Installation
# Flutter (client-side)
flutter pub add appwrite
# Dart (server-side)
dart pub add dart_appwrite
Setting Up the Client
Client-side (Flutter)
import 'package:appwrite/appwrite.dart';
final client = Client()
.setEndpoint('https://<REGION>.cloud.appwrite.io/v1')
.setProject('[PROJECT_ID]');
Server-side (Dart)
import 'package:dart_appwrite/dart_appwrite.dart';
final client = Client()
.setEndpoint('https://<REGION>.cloud.appwrite.io/v1')
.setProject(Platform.environment['APPWRITE_PROJECT_ID']!)
.setKey(Platform.environment['APPWRITE_API_KEY']!);
Code Examples
Authentication (client-side)
final account = Account(client);
// Signup
await account.create(userId: ID.unique(), email: 'user@example.com', password: 'password123', name: 'User Name');
// Login
final session = await account.createEmailPasswordSession(email: 'user@example.com', password: 'password123');
// OAuth login
await account.createOAuth2Session(provider: OAuthProvider.google);
// Get current user
final user = await account.get();
// Logout
await account.deleteSession(sessionId: 'current');
User Management (server-side)
final users = Users(client);
// Create user
final user = await users.create(userId: ID.unique(), email: 'user@example.com', password: 'password123', name: 'User Name');
// List users
final list = await users.list(queries: [Query.limit(25)]);
// Get user
final fetched = await users.get(userId: '[USER_ID]');
// Delete user
await users.delete(userId: '[USER_ID]');
Database Operations
Note: Use
TablesDB(not the deprecatedDatabasesclass) for all new code. Only useDatabasesif the existing codebase already relies on it or the user explicitly requests it.Tip: Prefer named parameters (e.g.,
databaseId: '...') for all SDK method calls. Only use positional arguments if the existing codebase already uses them or the user explicitly requests it.
final tablesDB = TablesDB(client);
// Create database (server-side only)
final db = await tablesDB.create(databaseId: ID.unique(), name: 'My Database');
// Create table (server-side only)
final col = await tablesDB.createTable(databaseId: '[DATABASE_ID]', tableId: ID.unique(), name: 'My Table');
// Create row
final doc = await tablesDB.createRow(
databaseId: '[DATABASE_ID]',
tableId: '[TABLE_ID]',
rowId: ID.unique(),
data: {'title': 'Hello', 'done': false},
);
// Query rows
final results = await tablesDB.listRows(
databaseId: '[DATABASE_ID]',
tableId: '[TABLE_ID]',
queries: [Query.equal('done', false), Query.limit(10)],
);
// Get row
final row = await tablesDB.getRow(databaseId: '[DATABASE_ID]', tableId: '[TABLE_ID]', rowId: '[ROW_ID]');
// Update row
await tablesDB.updateRow(
databaseId: '[DATABASE_ID]',
tableId: '[TABLE_ID]',
rowId: '[ROW_ID]',
data: {'done': true},
);
// Delete row
await tablesDB.deleteRow(
databaseId: '[DATABASE_ID]',
tableId: '[TABLE_ID]',
rowId: '[ROW_ID]',
);
String Column Types
Note: The legacy
stringtype is deprecated. Use explicit column types for all new columns.
| Type | Max characters | Indexing | Storage |
|---|---|---|---|
varchar | 16,383 | Full index (if size ≤ 768) | Inline in row |
text | 16,383 | Prefix only | Off-page |
mediumtext | 4,194,303 | Prefix only | Off-page |
longtext | 1,073,741,823 | Prefix only | Off-page |
varcharis stored inline and counts towards the 64 KB row size limit. Prefer for short, indexed fields like names, slugs, or identifiers.text,mediumtext, andlongtextare stored off-page (only a 20-byte pointer lives in the row), so they don't consume the row size budget.sizeis not required for these types.
// Create table with explicit string column types
await tablesDB.createTable(
databaseId: '[DATABASE_ID]',
tableId: ID.unique(),
name: 'articles',
columns: [
{'key': 'title', 'type': 'varchar', 'size': 255, 'required': true}, // inline, fully indexable
{'key': 'summary', 'type': 'text', 'required': false}, // off-page, prefix index only
{'key': 'body', 'type': 'mediumtext', 'required': false}, // up to ~4 M chars
{'key': 'raw_data', 'type': 'longtext', 'required': false}, // up to ~1 B chars
],
);
Query Methods
// Filtering
Query.equal('field', 'value') // == (or pass list for IN)
Query.notEqual('field', 'value') // !=
Query.lessThan('field', 100) // <
Query.lessThanEqual('field', 100) // <=
Query.greaterThan('field', 100) // >
Query.greaterThanEqual('field', 100) // >=
Query.between('field', 1, 100) // 1 <= field <= 100
Query.isNull('field') // is null
Query.isNotNull('field') // is not null
Query.startsWith('field', 'prefix') // starts with
Query.endsWith('field', 'suffix') // ends with
Query.contains('field', 'sub') // contains
Query.search('field', 'keywords') // full-text search (requires index)
// Sorting
Query.orderAsc('field')
Query.orderDesc('field')
// Pagination
Query.limit(25) // max rows (default 25, max 100)
Query.offset(0) // skip N rows
Query.cursorAfter('[ROW_ID]') // cursor pagination (preferred)
Query.cursorBefore('[ROW_ID]')
// Selection & Logic
Query.select(['field1', 'field2']) // return only specified fields
Query.or([Query.equal('a', 1), Query.equal('b', 2)]) // OR
Query.and([Query.greaterThan('age', 18), Query.lessThan('age', 65)]) // AND (default)
File Storage
final storage = Storage(client);
// Upload file
final file = await storage.createFile(
bucketId: '[BUCKET_ID]',
fileId: ID.unique(),
file: InputFile.fromPath(path: '/path/to/file.png', filename: 'file.png'),
);
// Get file preview
final preview = storage.getFilePreview(bucketId: '[BUCKET_ID]', fileId: '[FILE_ID]', width: 300, height: 300);
// List files
final files = await storage.listFiles(bucketId: '[BUCKET_ID]');
// Delete file
await storage.deleteFile(bucketId: '[BUCKET_ID]', fileId: '[FILE_ID]');
InputFile Factory Methods
// Client-side (Flutter)
InputFile.fromPath(path: '/path/to/file.png', filename: 'file.png') // from path
InputFile.fromBytes(bytes: uint8List, filename: 'file.png') // from Uint8List
// Server-side (Dart)
InputFile.fromPath(path: '/path/to/file.png', filename: 'file.png')
InputFile.fromBytes(bytes: uint8List, filename: 'file.png')
Teams
final teams = Teams(client);
// Create team
final team = await teams.create(teamId: ID.unique(), name: 'Engineering');
// List teams
final list = await teams.list();
// Create membership (invite user by email)
final membership = await teams.createMembership(
teamId: '[TEAM_ID]',
roles: ['editor'],
email: 'user@example.com',
);
// List memberships
final members = await teams.listMemberships(teamId: '[TEAM_ID]');
// Update membership roles
await teams.updateMembership(teamId: '[TEAM_ID]', membershipId: '[MEMBERSHIP_ID]', roles: ['admin']);
// Delete team
await teams.delete(teamId: '[TEAM_ID]');
Role-based access: Use
Role.team('[TEAM_ID]')for all team members orRole.team('[TEAM_ID]', 'editor')for a specific team role when setting permissions.
Real-time Subscriptions (client-side)
final realtime = Realtime(client);
// Subscribe to row changes
final subscription = realtime.subscribe([
Channel.tablesdb('[DATABASE_ID]').table('[TABLE_ID]').row(),
]);
subscription.stream.listen((response) {
print(response.events); // e.g. ['tablesdb.*.tables.*.rows.*.create']
print(response.payload); // the affected resource
});
// Subscribe to multiple channels
final multi = realtime.subscribe([
Channel.tablesdb('[DATABASE_ID]').table('[TABLE_ID]').row(),
Channel.bucket('[BUCKET_ID]').file(),
]);
// Cleanup
subscription.close();
Available channels:
| Channel | Description |
|---|---|
account | Changes to the authenticated user's account |
tablesdb.[DB_ID].tables.[TABLE_ID].rows | All rows in a table |
tablesdb.[DB_ID].tables.[TABLE_ID].rows.[ROW_ID] | A specific row |
buckets.[BUCKET_ID].files | All files in a bucket |
buckets.[BUCKET_ID].files.[FILE_ID] | A specific file |
teams | Changes to teams the user belongs to |
teams.[TEAM_ID] | A specific team |
memberships | The user's team memberships |
memberships.[MEMBERSHIP_ID] | A specific membership |
functions.[FUNCTION_ID].executions | Function execution updates |
Response fields: events (array), payload (resource), channels (matched), timestamp (ISO 8601).
Serverless Functions (server-side)
final functions = Functions(client);
// Execute function
final execution = await functions.createExecution(functionId: '[FUNCTION_ID]', body: '{"key": "value"}');
// List executions
final executions = await functions.listExecutions(functionId: '[FUNCTION_ID]');
Writing a Function Handler (Dart runtime)
// lib/main.dart — Appwrite Function entry point
Future<dynamic> main(final context) async {
// context.req.body — raw body (String)
// context.req.bodyJson — parsed JSON (Map or null)
// context.req.headers — headers (Map)
// context.req.method — HTTP method
// context.req.path — URL path
// context.req.query — query params (Map)
context.log('Processing: ${context.req.method} ${context.req.path}');
if (context.req.method == 'GET') {
return context.res.json({'message': 'Hello from Appwrite Function!'});
}
return context.res.json({'success': true}); // JSON
// return context.res.text('Hello'); // plain text
// return context.res.empty(); // 204
// return context.res.redirect('https://...'); // 302
}
Server-Side Rendering (SSR) Authentication
SSR apps using server-side Dart (Dart Frog, Shelf, etc.) use the server SDK (dart_appwrite) to handle auth. You need two clients:
- Admin client — uses an API key, creates sessions, bypasses rate limits (reusable singleton)
- Session client — uses a session cookie, acts on behalf of a user (create per-request, never share)
import 'package:dart_appwrite/dart_appwrite.dart';
// Admin client (reusable)
final adminClient = Client()
.setEndpoint('https://<REGION>.cloud.appwrite.io/v1')
.setProject('[PROJECT_ID]')
.setKey(Platform.environment['APPWRITE_API_KEY']!);
// Session client (create per-request)
final sessionClient = Client()
.setEndpoint('https://<REGION>.cloud.appwrite.io/v1')
.setProject('[PROJECT_ID]');
final session = request.cookies['a_session_[PROJECT_ID]'];
if (session != null) {
sessionClient.setSession(session);
}
Email/Password Login
final account = Account(adminClient);
final session = await account.createEmailPasswordSession(
email: body['email'],
password: body['password'],
);
// Cookie name must be a_session_<PROJECT_ID>
response.headers.add('Set-Cookie',
'a_session_[PROJECT_ID]=${session.secret}; '
'HttpOnly; Secure; SameSite=Strict; '
'Expires=${HttpDate.format(DateTime.parse(session.expire))}; Path=/');
Authenticated Requests
final session = request.cookies['a_session_[PROJECT_ID]'];
if (session == null) {
return Response(statusCode: 401, body: 'Unauthorized');
}
final sessionClient = Client()
.setEndpoint('https://<REGION>.cloud.appwrite.io/v1')
.setProject('[PROJECT_ID]')
.setSession(session);
final account = Account(sessionClient);
final user = await account.get();
OAuth2 SSR Flow
// Step 1: Redirect to OAuth provider
final account = Account(adminClient);
final redirectUrl = await account.createOAuth2Token(
provider: OAuthProvider.github,
success: 'https://example.com/oauth/success',
failure: 'https://example.com/oauth/failure',
);
return Response(statusCode: 302, headers: {'Location': redirectUrl});
// Step 2: Handle callback — exchange token for session
final account = Account(adminClient);
final session = await account.createSession(
userId: request.uri.queryParameters['userId']!,
secret: request.uri.queryParameters['secret']!,
);
// Set session cookie as above
Cookie security: Always use
HttpOnly,Secure, andSameSite=Strictto prevent XSS. The cookie name must bea_session_<PROJECT_ID>.
Forwarding user agent: Call
sessionClient.setForwardedUserAgent(request.headers['user-agent'])to record the end-user's browser info for debugging and security.
Error Handling
import 'package:appwrite/appwrite.dart';
// AppwriteException is included in the main import
try {
final row = await tablesDB.getRow(databaseId: '[DATABASE_ID]', tableId: '[TABLE_ID]', rowId: '[ROW_ID]');
} on AppwriteException catch (e) {
print(e.message); // human-readable message
print(e.code); // HTTP status code (int)
print(e.type); // error type (e.g. 'document_not_found')
print(e.response); // full response body (Map)
}
Common error codes:
| Code | Meaning |
|---|---|
401 | Unauthorized — missing or invalid session/API key |
403 | Forbidden — insufficient permissions |
404 | Not found — resource does not exist |
409 | Conflict — duplicate ID or unique constraint |
429 | Rate limited — too many requests |
Permissions & Roles (Critical)
Appwrite uses permission strings to control access to resources. Each permission pairs an action (read, update, delete, create, or write which grants create + update + delete) with a role target. By default, no user has access unless permissions are explicitly set at the document/file level or inherited from the collection/bucket settings. Permissions are arrays of strings built with the Permission and Role helpers.
import 'package:appwrite/appwrite.dart';
// Permission and Role are included in the main package import
Database Row with Permissions
final doc = await tablesDB.createRow(
databaseId: '[DATABASE_ID]',
tableId: '[TABLE_ID]',
rowId: ID.unique(),
data: {'title': 'Hello World'},
permissions: [
Permission.read(Role.user('[USER_ID]')), // specific user can read
Permission.update(Role.user('[USER_ID]')), // specific user can update
Permission.read(Role.team('[TEAM_ID]')), // all team members can read
Permission.read(Role.any()), // anyone (including guests) can read
],
);
File Upload with Permissions
final file = await storage.createFile(
bucketId: '[BUCKET_ID]',
fileId: ID.unique(),
file: InputFile.fromPath(path: '/path/to/file.png', filename: 'file.png'),
permissions: [
Permission.read(Role.any()),
Permission.update(Role.user('[USER_ID]')),
Permission.delete(Role.user('[USER_ID]')),
],
);
When to set permissions: Set document/file-level permissions when you need per-resource access control. If all documents in a collection share the same rules, configure permissions at the collection/bucket level and leave document permissions empty.
Common mistakes:
- Forgetting permissions — the resource becomes inaccessible to all users (including the creator)
Role.any()withwrite/update/delete— allows any user, including unauthenticated guests, to modify or remove the resourcePermission.read(Role.any())on sensitive data — makes the resource publicly readable