# Introduction
Starcounter 3.0.0 Release Candidate is available for general access.
Downloads:
* [`Starcounter.3.0.0-rc-20191212.zip`](https://starcounter.io/Starcounter/Starcounter.3.0.0-rc-20191212.zip) archive with all required NuGet packages.
* [`star-3.0.0-rc-20191212.zip`](https://starcounter.io/Starcounter/star-3.0.0-rc-20191212.zip) Starcounter command line `star` tool for Windows.
* [`star-3.0.0-rc-20191212.tar.gz`](https://starcounter.io/Starcounter/star-3.0.0-rc-20191212.tar.gz) Starcounter command line `star` tool for Linux.
Please make sure to read our [End User License Agreement for Starcounter Software](https://starcounter.com/wp-content/themes/starcounter-custom/assets/docs/Starcounter_EULA.pdf).
## Starcounter 3.0 release candidate `20191212` main changes
* [Starcounter failover](https://docs.starcounter.io/failover-cluster) setup using Windows Failover Cluster.
* The `star` tool is a cross-platform console application with SQL REPL & database import/export features.
* Starcounter apps can now be distributed as a regular .NET Core app in framework dependent and self contained modes. [Read more](https://docs.starcounter.io/publish-app).
* It's now possible to execute DML & DDL SQL statements using the `star` tool.
* Starcounter namespace has been changed from `Starcounter.Nova.App` to `Starcounter.Database`.
### Dependency Injection (DI) and Starcounter
* Read more about Dependency Injection on the official Microsoft documentation page - [Dependency injection in ASP.NET Core](https://docs.microsoft.com/en-us/aspnet/core/fundamentals/dependency-injection?view=aspnetcore-3.0).
* Checkout [ASP.NET Core sample](https://docs.starcounter.io/dependency-injection) controller with Starcounter database access using Dependency Injection (DI).
## Requirements
* [Ubuntu 18.04.02 x64](https://ubuntu.com/download/desktop) or [Windows 10 Pro x64 Build 1903](https://www.microsoft.com/en-us/software-download/windows10).
* [Windows Subsystem for Linux (WSL)](https://docs.microsoft.com/en-us/windows/wsl/install-win10) is also supported.
* [Ubuntu 19.10 x64](https://ubuntu.com/download/desktop) is also supported.
* [.NET Core 3.0.100](https://dotnet.microsoft.com/download/dotnet-core/3.0), SDK for development, runtime for production.
* Enough RAM to load database of targeted size.
* It's recommended to have at least two CPU cores.
**Note**: Please let us know if you encounter any issues while working with Starcounter. We monitor our [GitHub: Starcounter/Home](https://github.com/Starcounter/Home/issues) issue tracker and stand ready to assist.
## Installation
**Note**: This section assumes that you have required operating system and .NET Core `3.0.100` SDK installed.
### Binaries
* Create a folder for Starcounter binaries, for example `Starcounter.3.0.0-rc-20191212`.
* Download [`Starcounter.3.0.0-rc-20191212.zip`](https://starcounter.io/Starcounter/Starcounter.3.0.0-rc-20191212.zip) into the folder.
* Unzip downloaded archive into the folder.
#### Windows 10
On Windows Starcounter requires x64 version of Visual C++ to be installed. Download and install it from the Microsoft website:
[The latest supported Visual C++ downloads](https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads).
Make sure to `Unblock` the archive after downloading prior to extracting it. See the screenshot below:
#### Ubuntu 18.04 & 19.10
**Install prerequisites.**
```
sudo apt-get install wget unzip
sudo apt-get install libaio1 libtinfo5
```
Starcounter relies on a specific version of [SWI-Prolog](https://wwu-pi.github.io/tutorials/lectures/lsp/010_install_swi_prolog.html).
```
sudo add-apt-repository ppa:swi-prolog/stable
sudo apt-get update
sudo apt-get install swi-prolog-nox=7.\*
```
**Download and unpack Starcounter binaries.**
```
cd $HOME
mkdir Starcounter.3.0.0-rc-20191212
cd Starcounter.3.0.0-rc-20191212
wget https://starcounter.io/Starcounter/Starcounter.3.0.0-rc-20191212.zip
unzip Starcounter.3.0.0-rc-20191212.zip
```
### Application
**Create an application folder and initialize a .NET Core console application.**
```
mkdir StarcounterConsoleSample
cd StarcounterConsoleSample
dotnet new console
```
All the following commands shall be executed from the `StarcounterConsoleSample` folder.
**Setup NuGet to consume Starcounter packages feeds.**
Create `nuget.config` file and add required package sources:
* `local`, points to the Starcounter binaries folder.
* `Starcounter`, points to `https://www.myget.org/F/starcounter/api/v2`.
**NuGet tips**:
* Default `NuGet.config` file can be created with [`dotnet new nugetconfig`](https://docs.microsoft.com/en-us/dotnet/core/tools/dotnet-new) command.
* For more information on how to work with NuGet configurations, see [this post](https://docs.microsoft.com/en-us/nuget/consume-packages/configuring-nuget-behavior) by Microsoft.
**End file should look similar to this**:
```markup
```
**Visual Studio Setup**:
Visual Studio requires manual NuGet package sources configuration. For this go to the `Tools → Options → NuGet Package Manager → Package Sources` menu then add `local` and `Starcounter` feeds.
**Note**: Replace the `[Starcounter.3.0.0-rc-20191212]` value with the actual path to the folder with unzipped Starcounter binaries.
**Add Starcounter.Database package reference**
```
dotnet add package Starcounter.Database --version 3.0.0-*
```
**Add minimal Starcounter database access**
Replace content of the `Program.cs` file with the following:
```csharp
using System;
using System.Linq;
using Starcounter.Database;
using Microsoft.Extensions.DependencyInjection;
namespace StarcounterConsoleSample
{
[Database]
public abstract class Person
{
public abstract string Name { get; set; }
}
public class Program
{
public static void Main()
{
string connectionString =
"Database=./.database/StarcounterConsoleSample;"
+ "OpenMode=CreateIfNotExists;"
+ "StartMode=StartIfNotRunning;"
+ "StopMode=IfWeStarted";
// Here we create a service collection that
// we add the Starcounter services to.
// When we call BuildServiceProvider(), we get an instance
// that we can use to fetch service instances,
// for example ITransactor, which we then can use to
// to make database transactions.
using var services = new ServiceCollection()
.AddStarcounter(connectionString)
.BuildServiceProvider();
// Here we fetch our ITransactor instance from the service provider.
var transactor = services.GetRequiredService();
// And here we use it to make a database transaction.
var name = transactor.Transact(db =>
{
// Here inside the transaction,
// we can use the IDatabaseContext instance
// to interact with the Starcounter database.
// We can query it using SQL
// (which returns an IEnumerable
// that we can use with LINQ).
var p = db.Sql
(
"SELECT p FROM Person p WHERE Name = ?",
"Jane"
).FirstOrDefault();
if (p == null)
{
// We can insert new rows in the database using Insert().
p = db.Insert();
// We write to the database row
// using standard C# property accessors.
p.Name = "Jane";
}
// Let's return the name as result of the transaction.
return p.Name;
});
// And let's print it in the console
Console.WriteLine(name);
}
}
}
```
* [Read more about Starcounter database connection string](https://docs.starcounter.io/database-connection-string).
* [Read how to configure Starcounter database creation options](https://docs.starcounter.io/database-creation-options).
**For ASP.NET Core applications**:
Update `Startup.cs` class with the following:
```csharp
using Microsoft.AspNetCore.Builder;
using Microsoft.Extensions.DependencyInjection;
namespace StarcounterMvcSample
{
public class Startup
{
public void ConfigureServices(IServiceCollection services)
{
string connectionString =
"Database=./.database/StarcounterMvcSample;"
+ "OpenMode=CreateIfNotExists;"
+ "StartMode=StartIfNotRunning;"
+ "StopMode=IfWeStarted";
// This adds and configures Starcounter services to our application,
// for example ITransactor,
// that allows us to create database transactions.
services.AddStarcounter(connectionString);
}
}
}
```
**Note**: Starcounter works with Kestrel Web Server only. IIS and IIS Express are not yet supported.
## Running with [Visual Studio Code](https://code.visualstudio.com/Download)
* Open Visual Studio Code in the application folder (from command line: `code ./`).
* Restore dependencies Visual Studio Code asks for.
* Click `Ctrl + F5` to start the application.
Everything should run out of the box.
## Running with [Visual Studio 2019](https://visualstudio.microsoft.com/vs/)
* Update Visual Studio 2019 to the latest version using Visual Studio Installer.
* We checked version 16.3.0.
* Open `StarcounterConsoleSample.csproj` from Visual Studio.
* Click `Ctrl + F5` to start the application.
## Extra information
*Before asking questions or reporting issues, please read these few lines, and maybe you will find an answer for your question.*
* Publishing application in a single file with [`dotnet publish /p:PublishSingleFile=true`](https://docs.microsoft.com/en-us/dotnet/core/tools/dotnet-publish) is not yet supported.
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