feat(discovery): schedule saved-search alerts

2026-08-31 22:12:52 +02:00
parent 19a89018a0
commit b7029faaec
16 changed files with 423 additions and 113 deletions
@@ -0,0 +1,86 @@
+using JobTrackerApi.Data;
+using JobTrackerApi.Models;
+using Microsoft.EntityFrameworkCore;
+
+namespace JobTrackerApi.Services;
+
+public sealed class SavedJobSearchAlertHostedService(
+    BackgroundTenantRunner tenants,
+    IConfiguration configuration,
+    ILogger<SavedJobSearchAlertHostedService> logger,
+    IStartupReadiness startupReadiness,
+    TimeProvider timeProvider) : BackgroundService
+{
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        await startupReadiness.WaitUntilReadyAsync(stoppingToken);
+        if (!IsEnabled())
+        {
+            logger.LogInformation("Saved job search alert worker disabled.");
+            return;
+        }
+
+        await Task.Delay(TimeSpan.FromSeconds(30), timeProvider, stoppingToken);
+        while (!stoppingToken.IsCancellationRequested)
+        {
+            await RunOnceAsync(stoppingToken);
+            await Task.Delay(GetInterval(), timeProvider, stoppingToken);
+        }
+    }
+
+    public Task<BackgroundWorkerRunResult> RunOnceAsync(CancellationToken cancellationToken) =>
+        IsEnabled()
+            ? tenants.RunForSavedSearchOwnersAsync("saved-job-search-alerts", ProcessOwnerAsync, cancellationToken)
+            : Task.FromResult(BackgroundWorkerRunResult.Disabled);
+
+    private bool IsEnabled() => configuration.GetValue("Workers:SavedJobSearchAlertsEnabled", true);
+
+    private TimeSpan GetInterval() => TimeSpan.FromHours(Math.Clamp(
+        configuration.GetValue("JobDiscovery:SavedSearchIntervalHours", 6), 1, 24));
+
+    private async Task ProcessOwnerAsync(IServiceProvider services, CancellationToken cancellationToken)
+    {
+        var db = services.GetRequiredService<JobTrackerContext>();
+        var runner = services.GetRequiredService<SavedJobSearchRunner>();
+        var now = timeProvider.GetUtcNow();
+        var dueBefore = now - GetInterval();
+        var useNorwegian = string.Equals(
+            await db.Users.AsNoTracking().Where(user => user.Id == db.CurrentUserId).Select(user => user.UiLanguage).FirstOrDefaultAsync(cancellationToken),
+            "nb",
+            StringComparison.OrdinalIgnoreCase);
+        var searches = await db.SavedJobSearches.Include(search => search.Results)
+            .Where(search => search.IsActive)
+            .OrderBy(search => search.Id)
+            .ToListAsync(cancellationToken);
+
+        foreach (var search in searches.Where(search => search.LastRunAtUtc is null || search.LastRunAtUtc <= dueBefore))
+        {
+            var result = await runner.RunAsync(search, cancellationToken);
+            // The first automatic run establishes a baseline. Alert only for vacancies
+            // that appear after that baseline so existing results never look "new".
+            if (!result.WasInitialRun && result.NewCount > 0)
+            {
+                db.UserNotifications.Add(new UserNotification
+                {
+                    Id = Guid.NewGuid(),
+                    OwnerUserId = search.OwnerUserId,
+                    Kind = "saved_search_results",
+                    Title = useNorwegian
+                        ? result.NewCount == 1 ? "Ny stilling funnet" : $"{result.NewCount} nye stillinger funnet"
+                        : result.NewCount == 1 ? "New vacancy found" : $"{result.NewCount} new vacancies found",
+                    Message = useNorwegian
+                        ? result.NewCount == 1
+                            ? $"Det lagrede søket «{search.Name}» fant en ny stilling."
+                            : $"Det lagrede søket «{search.Name}» fant {result.NewCount} nye stillinger."
+                        : result.NewCount == 1
+                            ? $"Your saved search ‘{search.Name}’ found a new vacancy."
+                            : $"Your saved search ‘{search.Name}’ found {result.NewCount} new vacancies.",
+                    LinkPath = "/discover",
+                    CreatedAtUtc = now.UtcDateTime
+                });
+            }
+        }
+
+        await db.SaveChangesAsync(cancellationToken);
+    }
+}