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Entity Framework Core storage

Persists the op log and snapshots in any database EF Core supports, through your existing DbContext.

Install

dotnet add package OpStream.Server.Storage.EntityFrameworkCore

Setup

builder.Services.AddDbContext<AppDbContext>(options =>
    options.UseSqlServer(builder.Configuration.GetConnectionString("App")));

builder.Services
    .AddOpStream()
    .UseEfCoreStorage<AppDbContext>();

The package adds two entities to your context — OpStreamStoredOp and OpStreamSnapshot — via IModelConfiguration. Run dotnet ef migrations add ... to generate the tables.

Provider compatibility

UseEfCoreStorage<TContext> is provider-agnostic — it works with any EF Core provider you've already configured on your context:

  • SQL Server
  • PostgreSQL (Npgsql)
  • MySQL (Pomelo)
  • SQLite
  • Oracle
  • Cosmos DB
  • …

If you already use EF Core, this is almost always the easiest path. For fresh deployments without an existing context, the dedicated provider packages (SQL Server, PostgreSQL, …) add the schema directly without needing your own DbContext.

Schema

The migration adds two tables (default names; customizable via OnModelCreating overrides on your context):

CREATE TABLE OpStreamStoredOps (
    DocumentId  NVARCHAR(255) NOT NULL,
    Revision    BIGINT        NOT NULL,
    AuthorId    NVARCHAR(255) NOT NULL,
    Timestamp   DATETIMEOFFSET NOT NULL,
    Payload     VARBINARY(MAX) NOT NULL,
    EngineType  NVARCHAR(255) NOT NULL,
    PRIMARY KEY (DocumentId, Revision)
);

CREATE TABLE OpStreamSnapshots (
    DocumentId  NVARCHAR(255) PRIMARY KEY,
    Revision    BIGINT        NOT NULL,
    Timestamp   DATETIMEOFFSET NOT NULL,
    State       VARBINARY(MAX) NOT NULL
);

Performance notes

  • The op-log primary key (DocumentId, Revision) is also its cluster-aligned access pattern: every read is a forward scan from a base revision.
  • Snapshots compact the load path — see Snapshots.
  • For very high write throughput documents, consider Redis storage and use EF Core only for long-term archive.

When to pick this

  • You already have a DbContext and want one migration story.
  • You're targeting an EF-Core-supported database that doesn't have a dedicated OpStream provider.
  • You need sub-millisecond write latency — use Redis.