Aspose.Medical DICOM til tekstkonverter for .NET Knowledge Base
Hvordan man bruger Async DICOM JSON serialisering i ASP.NET Core Web APIs

Hvordan man bruger Async DICOM JSON serialisering i ASP.NET Core Web APIs

Denne tutorial viser, hvordan man bruger async DICOM JSON serialisering i ASP.NET Core web APIs. Asynk operationer er afgørende for high-throughput webapplikationer for at forhindre thread blokering og vedligeholde responsivitet under belastning.

Hvorfor bruge Async Serialization?

  • Skalaerbarhed:- Ikke-blokering I/O giver mulighed for at håndtere mere sammenhængende anmodninger.

    • afhængighed af ansvar *:- Web-servere forbliver responsive under store filbehandlinger.

  • • Ressourceeffektivitet:- Trusler frigives mens de venter på I/O-operationer.

Forside: Forberedelse af miljøet

  • Indstill Visual Studio eller ethvert kompatibelt .NET IDE.
  • Skab et nyt ASP.NET Core Web API-projekt, der tager sigte på .NET 8.
  • Installere Aspose.Medical fra NuGet Package Manager.

Step-by-Step Guide til Async DICOM JSON Serialisering

Trin 1: Installation af Aspose.Medical

Tilføj Aspose.Medicinsk bibliotek til dit projekt ved hjælp af NuGet.

Install-Package Aspose.Medical

Trin 2: Indtast de nødvendige navneområder

Tilføj henvisninger til de krævede navneområder i din kontroller.

using Aspose.Medical.Dicom;
using Aspose.Medical.Dicom.Serialization;
using Microsoft.AspNetCore.Mvc;

Trin 3: Skab Async Deserialization Endpoint

Skab et slutpunkt, der deserialiserer JSON fra anmodningsorganet.

[HttpPost("import")]
public async Task<IActionResult> ImportDicomJson()
{
    Dataset? dataset = await DicomJsonSerializer.DeserializeAsync(Request.Body);
    
    if (dataset == null)
        return BadRequest("Invalid DICOM JSON");
    
    return Ok("DICOM data imported successfully");
}

Trin 4: Skab Async Serialization Endpoint

Skab et slutpunkt, der serialiserer DICOM til JSON i svaret.

[HttpGet("export/{filename}")]
public async Task ExportDicomJson(string filename)
{
    DicomFile dcm = DicomFile.Open($"storage/{filename}");
    
    Response.ContentType = "application/json";
    await DicomJsonSerializer.SerializeAsync(Response.Body, dcm.Dataset);
}

Trin 5: Håndtering af annullering tokens

Pass annullering tokens for korrekt anmodning annullation håndtering.

[HttpPost("process")]
public async Task<IActionResult> ProcessDicomAsync(CancellationToken cancellationToken)
{
    Dataset? dataset = await DicomJsonSerializer.DeserializeAsync(
        Request.Body, 
        cancellationToken
    );
    
    if (cancellationToken.IsCancellationRequested)
        return StatusCode(499, "Client Closed Request");
    
    // Process dataset...
    return Ok();
}

Læs mere om ASP.NET Core Controller

Her er en komplet kontroller, der implementerer async DICOM JSON-operationer:

using Aspose.Medical.Dicom;
using Aspose.Medical.Dicom.Serialization;
using Microsoft.AspNetCore.Mvc;

namespace DicomApi.Controllers;

[ApiController]
[Route("api/[controller]")]
public class DicomController : ControllerBase
{
    private readonly string _storagePath = "dicom_storage";

    public DicomController()
    {
        Directory.CreateDirectory(_storagePath);
    }

    /// <summary>
    /// Import DICOM JSON and save as DICOM file
    /// </summary>
    [HttpPost("import")]
    public async Task<IActionResult> ImportDicomJson(CancellationToken cancellationToken)
    {
        try
        {
            Dataset? dataset = await DicomJsonSerializer.DeserializeAsync(
                Request.Body, 
                cancellationToken
            );

            if (dataset == null)
                return BadRequest("Failed to deserialize DICOM JSON");

            // Generate unique filename
            string filename = $"{Guid.NewGuid()}.dcm";
            string filepath = Path.Combine(_storagePath, filename);

            // Save as DICOM file
            DicomFile dcm = new DicomFile(dataset);
            dcm.Save(filepath);

            return Ok(new { message = "DICOM imported successfully", filename });
        }
        catch (OperationCanceledException)
        {
            return StatusCode(499, "Request cancelled");
        }
        catch (Exception ex)
        {
            return BadRequest($"Import failed: {ex.Message}");
        }
    }

    /// <summary>
    /// Export DICOM file as JSON stream
    /// </summary>
    [HttpGet("export/{filename}")]
    public async Task ExportDicomJson(string filename, CancellationToken cancellationToken)
    {
        string filepath = Path.Combine(_storagePath, filename);

        if (!System.IO.File.Exists(filepath))
        {
            Response.StatusCode = 404;
            await Response.WriteAsync("File not found");
            return;
        }

        try
        {
            DicomFile dcm = DicomFile.Open(filepath);
            
            Response.ContentType = "application/json";
            Response.Headers["Content-Disposition"] = $"attachment; filename=\"{filename}.json\"";
            
            await DicomJsonSerializer.SerializeAsync(
                Response.Body, 
                dcm.Dataset, 
                writeIndented: true
            );
        }
        catch (OperationCanceledException)
        {
            // Client disconnected
        }
        catch (Exception ex)
        {
            Response.StatusCode = 500;
            await Response.WriteAsync($"Export failed: {ex.Message}");
        }
    }

    /// <summary>
    /// Convert uploaded DICOM file to JSON
    /// </summary>
    [HttpPost("convert")]
    [RequestSizeLimit(100_000_000)] // 100MB limit
    public async Task ConvertDicomToJson(IFormFile file, CancellationToken cancellationToken)
    {
        if (file == null || file.Length == 0)
        {
            Response.StatusCode = 400;
            await Response.WriteAsync("No file uploaded");
            return;
        }

        try
        {
            // Save uploaded file temporarily
            string tempPath = Path.GetTempFileName();
            using (var stream = System.IO.File.Create(tempPath))
            {
                await file.CopyToAsync(stream, cancellationToken);
            }

            // Load and convert
            DicomFile dcm = DicomFile.Open(tempPath);
            
            Response.ContentType = "application/json";
            await DicomJsonSerializer.SerializeAsync(
                Response.Body, 
                dcm.Dataset, 
                writeIndented: true
            );

            // Cleanup temp file
            System.IO.File.Delete(tempPath);
        }
        catch (OperationCanceledException)
        {
            // Client disconnected
        }
        catch (Exception ex)
        {
            Response.StatusCode = 500;
            await Response.WriteAsync($"Conversion failed: {ex.Message}");
        }
    }
}

Konfigurer begrænsninger for anmodning

For store DICOM-filer konfigurerer du begæringsgrænser i Program.cs:

var builder = WebApplication.CreateBuilder(args);

// Configure Kestrel for large uploads
builder.WebHost.ConfigureKestrel(options =>
{
    options.Limits.MaxRequestBodySize = 500_000_000; // 500MB
});

// Configure form options
builder.Services.Configure<FormOptions>(options =>
{
    options.MultipartBodyLengthLimit = 500_000_000;
});

var app = builder.Build();

Eksempel på strømbearbejdning

Processer DICOM filer uden fuld opladning i hukommelsen:

[HttpPost("stream-process")]
public async Task StreamProcessDicom(CancellationToken cancellationToken)
{
    // Read JSON from request body stream
    using var reader = new StreamReader(Request.Body);
    string json = await reader.ReadToEndAsync(cancellationToken);
    
    // Deserialize
    Dataset? dataset = DicomJsonSerializer.Deserialize(json);
    
    if (dataset == null)
    {
        Response.StatusCode = 400;
        await Response.WriteAsync("Invalid JSON");
        return;
    }
    
    // Process and stream response
    Response.ContentType = "application/json";
    await DicomJsonSerializer.SerializeAsync(
        Response.Body, 
        dataset, 
        writeIndented: true
    );
}

Bedste metoder til fejlbehandling

Gennemførelse af omfattende fejlbehandling:

[HttpPost("safe-import")]
public async Task<IActionResult> SafeImportDicomJson(CancellationToken cancellationToken)
{
    try
    {
        Dataset? dataset = await DicomJsonSerializer.DeserializeAsync(
            Request.Body, 
            cancellationToken
        );

        if (dataset == null)
            return BadRequest(new { error = "Invalid DICOM JSON format" });

        // Process dataset...
        return Ok(new { success = true });
    }
    catch (OperationCanceledException)
    {
        return StatusCode(499, new { error = "Request cancelled by client" });
    }
    catch (JsonException ex)
    {
        return BadRequest(new { error = "JSON parsing error", details = ex.Message });
    }
    catch (OutOfMemoryException)
    {
        return StatusCode(507, new { error = "File too large to process" });
    }
    catch (Exception ex)
    {
        return StatusCode(500, new { error = "Internal server error", details = ex.Message });
    }
}

Yderligere bedste praksis

Brug af udsagn for strømme

Du skal altid bruge de rigtige mønstre:

using (FileStream fs = System.IO.File.OpenRead(filepath))
{
    // Process stream
}

Timeout konfiguration

Konfigurer passende timetider for lange operationer:

builder.WebHost.ConfigureKestrel(options =>
{
    options.Limits.RequestHeadersTimeout = TimeSpan.FromMinutes(2);
    options.Limits.KeepAliveTimeout = TimeSpan.FromMinutes(5);
});

Yderligere information

  • Async-metoder forbedrer skalerbarheden, men accelererer ikke nødvendigvis individuelle anmodninger.
  • Brug annullering tokens til korrekt at håndtere klientsvigt.
  • Overvåg hukommelsessystemet, når du behandler store DICOM-filer.

Konklusion

Denne tutorial har vist, hvordan man implementerer async DICOM JSON serialisering i ASP.NET Core web API’er ved hjælp af Aspose.Medical. Asynk operationer er afgørende for at opbygge skalerbare sundhedspleje APIs, der håndterer store medicinske billeddata effektivt.

 Dansk