SAP GWQ

2026-04-14 10:54:52 +02:00
parent df90a4a172
commit 36a22202bf
14 changed files with 678 additions and 78 deletions
@@ -0,0 +1,140 @@
+using System.Net.Http.Headers;
+using System.Text;
+using System.Text.Json;
+using System.Xml.Linq;
+
+namespace TrafagSalesExporter.Services;
+
+public class SapGatewayService : ISapGatewayService
+{
+    private static readonly XNamespace AppNs = "http://www.w3.org/2007/app";
+    private static readonly XNamespace EdmNs = "http://docs.oasis-open.org/odata/ns/edm";
+
+    public async Task TestConnectionAsync(string serviceUrl, string username, string password, CancellationToken cancellationToken = default)
+    {
+        using var client = CreateClient(username, password);
+        using var response = await client.GetAsync(BuildServiceUri(serviceUrl), cancellationToken);
+        response.EnsureSuccessStatusCode();
+    }
+
+    public async Task<List<string>> GetEntitySetsAsync(string serviceUrl, string username, string password, CancellationToken cancellationToken = default)
+    {
+        using var client = CreateClient(username, password);
+        var baseUrl = BuildServiceUri(serviceUrl);
+
+        var entitySets = await TryReadEntitySetsFromServiceRootAsync(client, baseUrl, cancellationToken);
+        if (entitySets.Count > 0)
+            return entitySets;
+
+        return await ReadEntitySetsFromMetadataAsync(client, baseUrl, cancellationToken);
+    }
+
+    public async Task<List<Dictionary<string, object?>>> GetEntityRowsAsync(string serviceUrl, string entitySet, string username, string password, CancellationToken cancellationToken = default)
+    {
+        using var client = CreateClient(username, password);
+        var requestUrl = $"{BuildServiceUri(serviceUrl)}{entitySet}?$format=json";
+        using var response = await client.GetAsync(requestUrl, cancellationToken);
+        response.EnsureSuccessStatusCode();
+
+        var json = await response.Content.ReadAsStringAsync(cancellationToken);
+        using var document = JsonDocument.Parse(json);
+        if (!document.RootElement.TryGetProperty("d", out var dNode))
+            return [];
+
+        if (!dNode.TryGetProperty("results", out var resultsNode) || resultsNode.ValueKind != JsonValueKind.Array)
+            return [];
+
+        var rows = new List<Dictionary<string, object?>>();
+        foreach (var item in resultsNode.EnumerateArray())
+        {
+            var row = new Dictionary<string, object?>(StringComparer.OrdinalIgnoreCase);
+            foreach (var property in item.EnumerateObject())
+            {
+                row[property.Name] = ConvertJsonValue(property.Value);
+            }
+
+            rows.Add(row);
+        }
+
+        return rows;
+    }
+
+    private static HttpClient CreateClient(string username, string password)
+    {
+        var client = new HttpClient();
+        client.Timeout = TimeSpan.FromSeconds(15);
+        client.DefaultRequestHeaders.Accept.Clear();
+        client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/atomsvc+xml"));
+        client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/xml"));
+        client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
+        client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue(
+            "Basic",
+            Convert.ToBase64String(Encoding.UTF8.GetBytes($"{username}:{password}")));
+        return client;
+    }
+
+    private static string BuildServiceUri(string serviceUrl)
+    {
+        var trimmed = serviceUrl.Trim();
+        if (string.IsNullOrWhiteSpace(trimmed))
+            throw new InvalidOperationException("SAP Service URL darf nicht leer sein.");
+
+        var entityPathMarker = "/sap/opu/odata/sap/";
+        var markerIndex = trimmed.IndexOf(entityPathMarker, StringComparison.OrdinalIgnoreCase);
+        if (markerIndex >= 0)
+        {
+            var servicePath = trimmed[(markerIndex + entityPathMarker.Length)..].Trim('/');
+            var parts = servicePath.Split('/', StringSplitOptions.RemoveEmptyEntries);
+            if (parts.Length > 1)
+            {
+                trimmed = $"{trimmed[..(markerIndex + entityPathMarker.Length)]}{parts[0]}/";
+            }
+        }
+
+        return trimmed.EndsWith('/') ? trimmed : $"{trimmed}/";
+    }
+
+    private static async Task<List<string>> TryReadEntitySetsFromServiceRootAsync(HttpClient client, string baseUrl, CancellationToken cancellationToken)
+    {
+        using var response = await client.GetAsync(baseUrl, cancellationToken);
+        response.EnsureSuccessStatusCode();
+
+        var xml = await response.Content.ReadAsStringAsync(cancellationToken);
+        var document = XDocument.Parse(xml);
+
+        return document
+            .Descendants(AppNs + "collection")
+            .Select(x => x.Attribute("href")?.Value ?? string.Empty)
+            .Where(x => !string.IsNullOrWhiteSpace(x))
+            .Distinct(StringComparer.OrdinalIgnoreCase)
+            .OrderBy(x => x, StringComparer.OrdinalIgnoreCase)
+            .ToList();
+    }
+
+    private static async Task<List<string>> ReadEntitySetsFromMetadataAsync(HttpClient client, string baseUrl, CancellationToken cancellationToken)
+    {
+        using var response = await client.GetAsync($"{baseUrl}$metadata", cancellationToken);
+        response.EnsureSuccessStatusCode();
+
+        var xml = await response.Content.ReadAsStringAsync(cancellationToken);
+        var document = XDocument.Parse(xml);
+
+        return document
+            .Descendants(EdmNs + "EntitySet")
+            .Select(x => x.Attribute("Name")?.Value ?? string.Empty)
+            .Where(x => !string.IsNullOrWhiteSpace(x))
+            .Distinct(StringComparer.OrdinalIgnoreCase)
+            .OrderBy(x => x, StringComparer.OrdinalIgnoreCase)
+            .ToList();
+    }
+
+    private static object? ConvertJsonValue(JsonElement element) => element.ValueKind switch
+    {
+        JsonValueKind.String => element.GetString(),
+        JsonValueKind.Number => element.ToString(),
+        JsonValueKind.True => true,
+        JsonValueKind.False => false,
+        JsonValueKind.Null => null,
+        _ => element.ToString()
+    };
+}