README.md

drift2csv / moor2csv

Supporting package for SQL/Drift/Moor, that allows easily exporting SQL-based Moor database to a CSV form, for external storage or sharing. Works on all platforms except Web.

Find Package on Official Dart Pub:

Usage Steps

First, perform necessary steps to provide Storage capability in the device you are developing for. Example: Editing android\app\src\main\AndroidManifest.xml and providing permissions for Android.

1. Set up a Moor/Drift Database in your flutter project and create necessary Data Structures and tables. Example:

   class Employees extends Table {
     TextColumn get employeeID => text()();
     TextColumn get name => text().withLength(max: 100).nullable()();
     IntColumn get phoneNo => integer().nullable()();
     TextColumn get deviceID => text().nullable()();
   
     @override
     Set<Column> get primaryKey => {employeeID};
   }
   
   @DriftDatabase(tables: [Employees])
   class Database extends _$Database {
     Database(QueryExecutor e) : super(e);
   
     @override
     int get schemaVersion => 1;
   
     // DATABASE OPERATIONS
     //EMPLOYEES
     Future<List<Employee>> getAllEmployees({
       String orderBy = 'asce',
       String mode = 'name',
     }) =>
         (select(employees)
               ..orderBy(
                 [
                   (u) {
                     GeneratedColumn<String?> criteria = employees.employeeID;
                     final OrderingMode order =
                         (mode == 'desc') ? OrderingMode.desc : OrderingMode.asc;
                     if (orderBy == 'id') {
                       criteria = employees.employeeID;
                     } else if (orderBy == 'name') {
                       criteria = employees.name;
                     } else if (orderBy == 'device') {
                       criteria = employees.deviceID;
                     }
                     return OrderingTerm(expression: criteria, mode: order);
                   }
                 ],
               ))
             .get();
   }

2. Run a query to get your List<DataClass> item from the Database.
   Example: List<Employee> _employees = await db.getAllEmployees(); in an async function gets us our List<DataClass> item from database db.

3. Simply Create a DriftSQLToCSV object and then use the writeToCSV() method by passing in the the List<DataClass> object as parameter to it (and optionally the CSV file name to save it as):

   // Assuming Employee is a DataClass
   final List<Employee> employees = [
       Employee(employeeID: '1', name: 'testA'),
       Employee(employeeID: '2', name: 'tenstB', phoneNo: 1203123112),
       Employee(employeeID: '3', name: 'temstC', deviceID: 'testDevice'),
       Employee(
           employeeID: '4', name: 'test,D', phoneNo: 132123124, deviceID: 's'),
     ]; // Replaced with values from database in actual implementation using select query get()
   
   // Using DriftSQLToCSV
   final DriftSQLToCSV DriftSQLToCSV = DriftSQLToCSV();
   await DriftSQLToCSV.writeToCSV(_employees, csvFileName: 'employees');

   It will do all the necessary work to export your Database to a CSV file. Example to store _employees object of type Employee table in employees.csv

4. The method also returns a Future<File> object that can be used to perform further operations on the saved CSV.

5. If the Database was successfully created, you will find it in:

   a. Android and IoS: Your Flutter App's internal Storage directory (eg. Android\Data\com.*.*\appName for Android), provided the permissions were given and the CSV was succesfully generated.

   b. Desktop Systems: Downloads Directory.

Dependencies

1. Moor/Drift (with Tables and DataClasses ready). (Moor requires dependencies like moor_generator and build_runner for full functioning. Make sure you are familiar before using this package)
2. Path Provider: To provide paths to Download folder (in desktop) and App Internal Storage Directory (in Mobile platforms) which are the only places storage of files is allowed
3. Permission Handler: To provide Storage read/write permission on Mobile devices. Moor itself requires it too.
4. Also uses dart:io library for file handling.

Available Methods

1. DriftSQLToCSV (Class constuctor): To create a DriftSQLToCSV object.

2. writeToCSV (Method): To write the CSV file to the device's storage. Returns a Future<File> object of the CSV file created.

3. permissionStatus / hasFileWritePermission (Getter): To get the current permission status of the app to write to storage.

Potential Contribution Ideas

1. Implement a way to view the generated CSVs that works across platforms. Right now I can't think of any. Tested out Open package and url_launcher with failure in one or more platforms. The only way to browse the generated CSVs is to manually browse to the storage folder.

2. Better documentation.

Getting Started

This project is a starting point for a Dart package, a library module containing code that can be shared easily across multiple Flutter or Dart projects.

For help getting started with Flutter, view our online documentation, which offers tutorials, samples, guidance on mobile development, and a full API reference.