Fix: Duration-based scheduling is properly formed

src/Dapr.Jobs/DaprJobsGrpcClient.cs

@@ -84,11 +84,12 @@ public override async Task ScheduleJobAsync(string jobName, DaprJobSchedule sche
         {
             job.DueTime = schedule.ExpressionValue;
         }
-        else if (schedule.IsCronExpression || schedule.IsDurationExpression || schedule.IsPrefixedPeriodExpression)
+        else if (schedule.IsCronExpression || schedule.IsPrefixedPeriodExpression || schedule.IsDurationExpression)
         {
             job.Schedule = schedule.ExpressionValue;
         }
-        else if (startingFrom is not null)
+
+        if (startingFrom is not null)
         {
             job.DueTime = ((DateTimeOffset)startingFrom).ToString("O");
         }

src/Dapr.Jobs/Extensions/TimeSpanExtensions.cs

@@ -67,7 +67,7 @@ public static string ToDurationString(this TimeSpan timespan)
     /// <returns>True if the string represents a parseable interval duration; false if not.</returns>
     public static bool IsDurationString(this string interval)
     {
-        interval = interval.Replace("ms", "q");
+        interval = interval.Replace("ms", "q").Replace("@every ", string.Empty);
         return hourRegex.Match(interval).Success || 
                minuteRegex.Match(interval).Success ||
                secondRegex.Match(interval).Success ||

src/Dapr.Jobs/Models/DaprJobSchedule.cs

@@ -65,11 +65,8 @@ public static DaprJobSchedule FromCronExpression(CronExpressionBuilder builder)
     /// </summary>
     /// <param name="scheduledTime">The date and time when the job should be triggered.</param>
     /// <returns></returns>
-    public static DaprJobSchedule FromDateTime(DateTimeOffset scheduledTime)
-    {
-        return new DaprJobSchedule(scheduledTime.ToString("O"));
-    }
-
+    public static DaprJobSchedule FromDateTime(DateTimeOffset scheduledTime) => new(scheduledTime.ToString("O"));
+
     /// <summary>
     /// Specifies a schedule using a Cron-like expression or '@' prefixed period strings.
     /// </summary>
@@ -86,10 +83,7 @@ public static DaprJobSchedule FromExpression(string expression)
     /// Specifies a schedule using a duration interval articulated via a <see cref="TimeSpan"/>.
     /// </summary>
     /// <param name="duration">The duration interval.</param>
-    public static DaprJobSchedule FromDuration(TimeSpan duration)
-    {
-        return new DaprJobSchedule(duration.ToDurationString());
-    }
+    public static DaprJobSchedule FromDuration(TimeSpan duration) => new($"@every {duration.ToDurationString()}");
 
     /// <summary>
     /// Specifies a schedule in which the job is triggered to run once a year.

test/Dapr.Jobs.Test/Models/DaprJobScheduleTests.cs

@@ -23,7 +23,16 @@ public sealed class DaprJobScheduleTests
     public void FromDuration_Validate()
     {
         var schedule = DaprJobSchedule.FromDuration(new TimeSpan(12, 8, 16));
-        Assert.Equal("12h8m16s", schedule.ExpressionValue);
+        Assert.Equal("@every 12h8m16s", schedule.ExpressionValue);
+    }
+
+    [Fact]
+    public void FromExpression_Duration()
+    {
+        var every5Seconds = new TimeSpan(0, 0, 0, 5);
+        var schedule = DaprJobSchedule.FromDuration(every5Seconds);
+
+        Assert.Equal("@every 5s", schedule.ExpressionValue);
     }
 
     [Fact]
@@ -108,7 +117,7 @@ public void IsDurationExpression()
         Assert.True(schedule.IsDurationExpression);
         Assert.False(schedule.IsPointInTimeExpression);
         Assert.False(schedule.IsCronExpression);
-        Assert.False(schedule.IsPrefixedPeriodExpression);
+        Assert.True(schedule.IsPrefixedPeriodExpression); //A duration expression _is_ a prefixed period with @every
     }
 
     [Fact]