Lab Ledger 🧪

Lab Ledger is a system for tracking lab samples, the tests you run on them, and the results you record — with role-based access, so different users can do different things.

If you’ve ever had sample info spread across emails, spreadsheets, and sticky notes, this is meant to replace that with one clear source of truth.

What you can do with it

• Track samples: what they are, where they came from, and their current status.
• Run tests: attach one or more tests to a sample and track progress.
• Record results: store the measured value, unit, and whether the result is published.
• Control access: different roles can do different things (see below).

Data model

• Users – email, fullName, role
• Samples – name, type, origin, status, submittedById
• Tests – method, status, sampleId, assignedToId
• Results – testId, value, unit, isPublished, recordedById, publishedById

Roles

Role	What they can do
Scientist	Work with samples (view, create, update)
Technician	Work with tests and results (and view samples)
Supervisor	Do almost everything (but not manage users)
Admin	Do everything, including user management

Endpoints

Lab Ledger offers the same data in two ways:

• REST API: regular HTTP endpoints like GET /api/samples
• GraphQL: available at /graphql, powered by GraphQL + Hot Chocolate

Most endpoints require you to be logged in. You log in once, then send the token with each request like so: Authorization: Bearer <your-token>

• Register a user: POST /api/auth/register
• Log in (get a token): POST /api/auth/login
• List all samples: GET /api/samples
• Get one sample: GET /api/samples/{id}
• Create a sample: POST /api/samples
• Update a sample’s status: PATCH /api/samples/{id}/status
• Create a test for a sample: POST /api/samples/{id}/tests
• Assign a test to someone: PATCH /api/tests/{id}/assign
• Update a test’s status: PATCH /api/tests/{id}/status
• Record a result for a test: POST /api/tests/{id}/result
• View a result: GET /api/results/{id}
• Publish a result: PATCH /api/results/{id}/publish

GraphQL

GraphQL is available at:

• POST /graphql

In development, Hot Chocolate also provides a browser UI at:

• GET /graphql

Example: query samples (optionally filter by status):

query {
  samples(status: Submitted) {
    id
    name
    status
  }
}

Tests

This project has 31 automated tests (unit + integration).

• How integration tests work: the API is spun up in-memory using Microsoft.AspNetCore.Mvc.Testing, then tests call the real HTTP endpoints (and GraphQL) like a client would.
• What’s covered: authentication (/api/auth/*), samples (/api/samples/*), tests + results (/api/tests/*, /api/results/*), GraphQL samples queries (/graphql), and global error handling.
• Coverage: code coverage is collected with Coverlet.

Tech stack

Area	Technology
Runtime	.NET 8 (net8.0)
Web API	ASP.NET Core
Auth	JWT Bearer auth (Microsoft.AspNetCore.Authentication.JwtBearer 8.0.11)
Database	SQLite
ORM / data access	Entity Framework Core (Microsoft.EntityFrameworkCore.Sqlite 8.0.11)
GraphQL	Hot Chocolate 16.0.9
Validation	FluentValidation (API: 11.3.1, Application: 12.1.1)
API docs	Swagger / Swashbuckle 6.6.2
Mapping	Mapster 10.0.7
Password hashing	BCrypt.Net-Next 4.2.0
Testing	xUnit 2.5.3, FluentAssertions 8.2.0, Moq 4.20.72
Test hosting	Microsoft.AspNetCore.Mvc.Testing 8.0.11
Coverage	coverlet.collector 6.0.0

Project layout

Path	What it is
LabLedger.sln	Main solution file
src/LabLedger.Api	The web API (the thing you run)
src/LabLedger.Application	Application logic
src/LabLedger.Core	Core domain interfaces
src/LabLedger.DataModel	Database model + migrations
tests/LabLedger.Tests	Automated tests

Quickstart

Run these commands from the repository root.

Prerequisites

Install the .NET 8 SDK

Build

dotnet build

Create/update the local database

Do this on first run, and again after schema changes:

dotnet ef database update --project src/LabLedger.DataModel --startup-project src/LabLedger.Api

Run the API

dotnet run --project src/LabLedger.Api

Visit the API docs (Swagger)

Once the API is running, open:

• http://localhost:5143/swagger

Visit GraphQL

Hot Chocolate GraphQL endpoint + dev UI:

• POST /graphql
• GET /graphql

Run the tests

Run everything:

dotnet test

Run a single test class or method (adjust the filter):

dotnet test --filter "FullyQualifiedName~AuthControllerTests"

Create a migration (when you change the data model)

dotnet ef migrations add <MigrationName> --project src/LabLedger.DataModel --startup-project src/LabLedger.Api