Schema Definition

A schema lists your collections and the model stored in each one. The code generator reads it and adds a typed accessor for every collection to FirestoreODM.

Define a schema

A schema file has three parts:

1. A schema class that extends FirestoreSchema. You write this class yourself.
2. A top-level constant of that class, annotated with @Schema() and one @Collection<Model>('path') per collection.
3. A part directive for the generated file.

// lib/schema.dart
import 'package:firestore_odm/firestore_odm.dart';

import 'models/post.dart';
import 'models/user.dart';

part 'schema.g.dart';

class AppSchema extends FirestoreSchema {
  const AppSchema();
}

@Schema()
@Collection<User>('users')
@Collection<Post>('posts')
@Collection<Post>('users/*/posts') // subcollection: one per user
const appSchema = AppSchema();

Every model used in a @Collection must carry @firestoreOdm (see Data Modeling). A * in a path stands for a parent document ID (see Subcollections).

Then generate the code:

dart run build_runner build --delete-conflicting-outputs

Create the ODM

import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:firestore_odm/firestore_odm.dart';

import 'schema.dart';

final odm = FirestoreODM(appSchema, firestore: FirebaseFirestore.instance);

final users = odm.users;            // root collection: a getter
final posts = odm.posts;
final alicePosts = odm.usersPosts('alice'); // subcollection: a method

firestore is optional and defaults to FirebaseFirestore.instance. Pass another instance to use a second database or an emulator (see Multiple ODM Instances).

Accessor names

Accessor names come from the collection path. Wildcard segments are dropped and the remaining segments are joined in camelCase:

Path	Accessor
users	odm.users
audit_logs	odm.auditLogs
users/*/posts	odm.usersPosts(userId)
users/*/posts/*/comments	odm.usersPostsComments(userId, postId)

The same model can appear in any number of collections; its generated code is shared.