Persist invoice validation reports as JSON blobs

src/ImportAssist.Core/ImportReport.cs

@@ -0,0 +1,19 @@
+namespace ImportAssist.Core;
+
+public sealed record InvoiceCheckResult(
+    int LineNumber,
+    string InvoiceId,
+    bool IsValid,
+    IReadOnlyList<string> Errors);
+
+public sealed record ImportReport(
+    string SourceBlob,
+    DateTimeOffset CheckedAtUtc,
+    string Status,
+    IReadOnlyList<InvoiceCheckResult> Rows,
+    IReadOnlyList<string> FileErrors)
+{
+    public int TotalCount => Rows.Count;
+    public int ValidCount => Rows.Count(row => row.IsValid);
+    public int InvalidCount => TotalCount - ValidCount;
+}

src/ImportAssist.Functions/InvoiceBlobTrigger.cs

@@ -1,3 +1,4 @@
+using System.Text.Json;
 using ImportAssist.Core;
 using Microsoft.Azure.Functions.Worker;
 using Microsoft.Extensions.Logging;
@@ -7,60 +8,69 @@ namespace ImportAssist_Functions;
 public sealed class InvoiceBlobTrigger(
     ILogger<InvoiceBlobTrigger> logger)
 {
+    private static readonly JsonSerializerOptions JsonOptions =
+        new(JsonSerializerDefaults.Web)
+        {
+            WriteIndented = true
+        };
+
     [Function("InvoiceBlobTrigger")]
-    public void Run(
+    [BlobOutput(
+        "results/{name}.json",
+        Connection = "AzureWebJobsStorage")]
+    public string Run(
         [BlobTrigger(
             "imports/{name}",
             Connection = "AzureWebJobsStorage")]
         string content,
         string name)
     {
-        IReadOnlyList<InvoiceRow> rows;
+        ImportReport report;
 
         try
         {
-            rows = InvoiceCsvParser.Parse(content);
+            var rows = InvoiceCsvParser.Parse(content);
+            var results = new List<InvoiceCheckResult>();
+
+            for (var index = 0; index < rows.Count; index++)
+            {
+                var row = rows[index];
+                var errors = InvoiceValidator.Validate(row);
+
+                results.Add(new InvoiceCheckResult(
+                    LineNumber: index + 2,
+                    InvoiceId: row.InvoiceId,
+                    IsValid: errors.Count == 0,
+                    Errors: errors));
+            }
+
+            report = new ImportReport(
+                SourceBlob: name,
+                CheckedAtUtc: DateTimeOffset.UtcNow,
+                Status: "Completed",
+                Rows: results,
+                FileErrors: []);
         }
         catch (FormatException exception)
         {
-            logger.LogWarning(
-                "Datei {BlobName} wegen CSV-Formatfehler abgewiesen: {Reason}",
-                name,
-                exception.Message);
-
-            return;
-        }
-
-        var validCount = 0;
-
-        foreach (var row in rows)
-        {
-            var errors = InvoiceValidator.Validate(row);
-
-            if (errors.Count == 0)
-            {
-                validCount++;
-            }
-
-            var invoiceId = string.IsNullOrWhiteSpace(row.InvoiceId)
-                ? "(ohne Rechnungsnummer)"
-                : row.InvoiceId;
-
-            logger.LogInformation(
-                "{BlobName}: {InvoiceId}: {Result}",
-                name,
-                invoiceId,
-                errors.Count == 0
-                    ? "Gültig"
-                    : string.Join("; ", errors));
+            report = new ImportReport(
+                SourceBlob: name,
+                CheckedAtUtc: DateTimeOffset.UtcNow,
+                Status: "Rejected",
+                Rows: [],
+                FileErrors: [exception.Message]);
         }
 
         logger.LogInformation(
-            "Dateiprüfung abgeschlossen: {BlobName}, " +
-            "{TotalCount} Rechnungen, {ValidCount} gültig, {InvalidCount} fehlerhaft.",
+            "Prüfbericht erstellt: {BlobName}, Status {Status}, " +
+            "{TotalCount} Rechnungen, {ValidCount} gültig, " +
+            "{InvalidCount} fehlerhaft.",
             name,
-            rows.Count,
-            validCount,
-            rows.Count - validCount);
+            report.Status,
+            report.TotalCount,
+            report.ValidCount,
+            report.InvalidCount);
+
+        return JsonSerializer.Serialize(report, JsonOptions);
     }
 }