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Rystem.RepositoryFramework.Infrastructure.InMemory 10.0.8

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Rystem.RepositoryFramework.Infrastructure.InMemory

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In-memory storage for the Rystem repository ecosystem, designed for local development, sample apps, integration tests, random data population, and resilience simulations.

This package sits on top of Rystem.RepositoryFramework.Abstractions and is usually the easiest concrete provider to start with when you want repository behavior without a real external database.

Resources

• Complete Documentation: https://rystem.net
• MCP Server for AI: https://rystem.cloud/mcp
• Discord Community: https://discord.gg/tkWvy4WPjt
• Support the Project: https://www.buymeacoffee.com/keyserdsoze

Installation

dotnet add package Rystem.RepositoryFramework.Infrastructure.InMemory

The current package metadata in src/Repository/RepositoryFramework.Infrastructure.InMemory/RepositoryFramework.Infrastructure.InMemory.csproj is:

• package id: Rystem.RepositoryFramework.Infrastructure.InMemory
• version: 10.0.6
• target framework: net10.0

Package architecture

What this package is good for

• fast tests that still go through repository contracts
• sample apps and demos that need realistic query/write behavior
• local development before wiring a real provider
• generating seeded datasets with System.Population.Random
• simulating latency and failures without external infrastructure

Quick start

builder.Services.AddRepository<User, string>(repositoryBuilder =>
{
 repositoryBuilder.WithInMemory();
});

var app = builder.Build();
await app.Services.WarmUpAsync();
app.Run();

WithInMemory() is available on:

• IRepositoryBuilder<T, TKey>
• ICommandBuilder<T, TKey>
• IQueryBuilder<T, TKey>

WarmUpAsync() is only required when you use the population helpers, but many repository-based apps already call it during startup for consistency across providers.

Registration API

All three overloads share the same signature and the same defaults.

.WithInMemory(
 Action<IRepositoryInMemoryBuilder<T, TKey>>? inMemoryBuilder = null,
 string? name = null,
 ServiceLifetime lifetime = ServiceLifetime.Singleton)

This provider uses SetStorageAndBuildOptions(...) from the abstractions layer under the hood.

How the in-memory store behaves

InMemoryStorage<T, TKey> stores data in a static ConcurrentDictionary<string, Entity<T, TKey>> keyed by KeySettings<TKey>.AsString(key).

That has a few practical consequences:

• data is shared per closed generic pair T and TKey
• inserts, updates, and reads are thread-safe at the dictionary level
• values are deep-cloned through JSON when written and when returned from GetAsync and QueryAsync
• the storage behaves more like a serialization boundary than a simple in-process reference cache

Important note about named registrations

Named registrations help you resolve different DI entries, but they do not create isolated backing stores for the same T and TKey pair.

For example, these two registrations resolve separately through IFactory<IRepository<User, string>>, but they still share the same underlying static dictionary:

builder.Services.AddRepository<User, string>(repositoryBuilder =>
{
 repositoryBuilder.WithInMemory(name: "default");
 repositoryBuilder.WithInMemory(name: "secondary");
});

So in this provider, name is primarily a DI-selection and warm-up-routing concept, not a data-partitioning mechanism.

Seeding and warm-up

The in-memory builder exposes three seeding styles:

• PopulateWithRandomData(...)
• PopulateWithDataInjection(...)
• PopulateWithJsonData(...)

These methods do not insert data immediately during service registration. They register warm-up actions, and those actions run when WarmUpAsync() is called on the built service provider.

Random data

PopulateWithRandomData(...) uses System.Population.Random and returns IPopulationBuilder<Entity<T, TKey>>, which is why the lambda examples target x.Value and x.Key.

builder.Services.AddRepository<NonPlusSuperUser, NonPlusSuperUserKey>(repositoryBuilder =>
{
 repositoryBuilder.WithInMemory(inMemoryBuilder =>
 {
 inMemoryBuilder
 .PopulateWithRandomData(120, 5)
 .WithPattern(x => x.Value!.Email, @"[a-z]{5,10}@gmail\.com");
 });
});

var app = builder.Build();
await app.Services.WarmUpAsync();

The two numeric parameters are:

• numberOfElements: how many root entities to generate
• numberOfElementsWhenEnumerableIsFound: how many items to generate for enumerable members

Customizing random generation

Because random population returns an IPopulationBuilder<Entity<T, TKey>>, you can use the population features from the core ecosystem.

Real tests in the repository use helpers such as:

• WithPattern(...)
• WithImplementation(...)
• WithValue(...)
• WithAutoIncrement(...)

repositoryBuilder.WithInMemory(inMemoryBuilder =>
{
 inMemoryBuilder
 .PopulateWithRandomData(90, 8)
 .WithAutoIncrement(x => x.Value!.Id, 0)
 .WithPattern(x => x.Value!.Email, @"[a-z]{5,10}@gmail\.com")
 .WithImplementation<IInnerInterface, MyInnerInterfaceImplementation>(x => x.Value!.Inner!)
 .WithValue(x => x.Value!.Enabled, () => true);
});

Inject from existing data

Use PopulateWithDataInjection(...) when you already have a list of entities.

var users = new List<User>
{
 new() { Id = "alice", Name = "Alice" },
 new() { Id = "bob", Name = "Bob" }
};

builder.Services.AddRepository<User, string>(repositoryBuilder =>
{
 repositoryBuilder.WithInMemory(inMemoryBuilder =>
 {
 inMemoryBuilder.PopulateWithDataInjection(x => x.Id, users);
 });
});

The key selector should point to a property that can be read from each entity.

Inject from JSON

Use PopulateWithJsonData(...) when the source is a JSON array of T.

var json = """
[
 { "Id": "alice", "Name": "Alice" },
 { "Id": "bob", "Name": "Bob" }
]
""";

builder.Services.AddRepository<User, string>(repositoryBuilder =>
{
 repositoryBuilder.WithInMemory(inMemoryBuilder =>
 {
 inMemoryBuilder.PopulateWithJsonData(x => x.Id, json);
 });
});

If the JSON cannot be deserialized into IEnumerable<T>, the builder simply leaves the store unchanged.

Warm-up behavior details

• PopulateWithRandomData(...), PopulateWithDataInjection(...), and PopulateWithJsonData(...) all seed through warm-up actions
• warm-up resolves the named repository/command/query registration when a name is provided
• plain WithInMemory() without population does not need warm-up to function, because InMemoryStorage<T, TKey>.BootstrapAsync() is currently a no-op

CRUD and query usage

Once registered, the provider behaves like any other repository implementation from the consumer side.

var result = await repository.InsertAsync(1, new Animal { Id = 1, Name = "Eagle" });
var item = await repository.GetAsync(1);
var exists = await repository.ExistAsync(1);

var page = await repository
 .Where(x => x.Id > 0)
 .OrderByDescending(x => x.Id)
 .PageAsync(1, 2);

var batch = repository.CreateBatchOperation();
for (var i = 0; i < 10; i++)
 batch.AddInsert(i, new Animal { Id = i, Name = i.ToString() });

await batch.ExecuteAsync().ToListAsync();

This exact style is covered by the in-memory all-methods tests in the repository.

Behavior simulation

The provider can simulate latency and failure probability per repository method family through RepositoryBehaviorSettings<T, TKey>.

builder.Services.AddRepository<User, string>(repositoryBuilder =>
{
 repositoryBuilder.WithInMemory(inMemoryBuilder =>
 {
 inMemoryBuilder.Settings.AddForCommandPattern(new MethodBehaviorSetting
 {
 MillisecondsOfWait = new Range(50, 200)
 });

 inMemoryBuilder.Settings.AddForQueryPattern(new MethodBehaviorSetting
 {
 MillisecondsOfWait = new Range(5, 20)
 });
 });
});

Configuration methods

MethodBehaviorSetting

ExceptionOdds

Validation rules

Before the options are finalized, the builder validates the configured percentages:

• each percentage must be greater than 0 and less than or equal to 100
• the total of one list cannot exceed 100

Invalid configurations throw during options building, not later at query time.

Important behavior differences by method

The provider does not simulate failures in the exact same way for every method.

Read-style methods

These methods throw the configured simulated exception when the probability path is hit:

• GetAsync
• QueryAsync
• OperationAsync

Command-style methods

These methods do not throw the configured exception. Instead, the simulated failure path returns a failed State<T, TKey>:

• InsertAsync
• UpdateAsync
• DeleteAsync
• ExistAsync

So for writes and ExistAsync, you should check state.IsOk rather than expect an exception.

Batch behavior

BatchAsync executes insert/update/delete operations one by one and yields a result for each operation. It is not transactional and does not roll back previous operations.

Also, as currently implemented, BatchAsync does not read the dedicated RepositoryMethods.Batch behavior setting directly. It inherits behavior from the individual insert/update/delete calls it performs.

That means AddForBatch(...) exists in the options API, but it is not consumed by InMemoryStorage<T, TKey> today.

CQRS variants

The same extension exists for command-only and query-only registrations.

builder.Services.AddCommand<Order, Guid>(commandBuilder =>
{
 commandBuilder.WithInMemory();
});

builder.Services.AddQuery<Product, int>(queryBuilder =>
{
 queryBuilder.WithInMemory(inMemoryBuilder =>
 {
 inMemoryBuilder.PopulateWithRandomData(50, 3);
 });
});

Because the concrete in-memory storage implements the full repository contract internally, warm-up seeding still works even when the public DI surface is query-only or command-only.

Practical examples from the repo

Sample web API seed data

The sample API under src/Repository/RepositoryFramework.Test/RepositoryFramework.WebApi/Program.cs registers repositories like this:

builder.Services.AddRepository<SuperUser, string>(repositoryBuilder =>
{
 repositoryBuilder.WithInMemory(inMemoryBuilder =>
 {
 inMemoryBuilder
 .PopulateWithRandomData(120, 5)
 .WithPattern(x => x.Value!.Email, @"[a-z]{5,10}@gmail\.com");
 });
});

var app = builder.Build();
await app.Services.WarmUpAsync();

Test-focused latency simulation

The population tests configure different delays for reads and writes:

repositoryBuilder.WithInMemory(inMemoryBuilder =>
{
 inMemoryBuilder.Settings.AddForCommandPattern(new MethodBehaviorSetting
 {
 MillisecondsOfWait = new Range(100, 250)
 });

 inMemoryBuilder.Settings.AddForQueryPattern(new MethodBehaviorSetting
 {
 MillisecondsOfWait = new Range(10, 40)
 });
});

Full exception distribution example

The exception tests configure a full distribution across several exceptions:

repositoryBuilder.WithInMemory(inMemoryBuilder =>
{
 inMemoryBuilder.Settings.AddForRepositoryPattern(new MethodBehaviorSetting
 {
 ExceptionOdds = new List<ExceptionOdds>
 {
 new() { Exception = new Exception("Normal Exception"), Percentage = 10.352 },
 new() { Exception = new Exception("Big Exception"), Percentage = 49.1 },
 new() { Exception = new Exception("Great Exception"), Percentage = 40.548 }
 }
 });
});

Related packages

If you are continuing through the repository area, this is usually the next package to understand after src/Repository/RepositoryFramework.Abstractions/README.md.