Min Bucket Aggregation Usageedit

a => a
.DateHistogram("projects_started_per_month", dh => dh
    .Field(p => p.StartedOn)
    .Interval(DateInterval.Month)
    .Aggregations(aa => aa
        .Sum("commits", sm => sm
            .Field(p => p.NumberOfCommits)
        )
    )
)
.MinBucket("min_commits_per_month", aaa => aaa
    .BucketsPath("projects_started_per_month>commits")
)
new DateHistogramAggregation("projects_started_per_month")
{
    Field = "startedOn",
    Interval = DateInterval.Month,
    Aggregations = new SumAggregation("commits", "numberOfCommits")
}
&& new MinBucketAggregation("min_commits_per_month", "projects_started_per_month>commits")

Example json output. 

{
  "projects_started_per_month": {
    "date_histogram": {
      "field": "startedOn",
      "interval": "month"
    },
    "aggs": {
      "commits": {
        "sum": {
          "field": "numberOfCommits"
        }
      }
    }
  },
  "min_commits_per_month": {
    "min_bucket": {
      "buckets_path": "projects_started_per_month>commits"
    }
  }
}

Handling Responsesedit

response.ShouldBeValid();

var projectsPerMonth = response.Aggregations.DateHistogram("projects_started_per_month");
projectsPerMonth.Should().NotBeNull();
projectsPerMonth.Buckets.Should().NotBeNull();
projectsPerMonth.Buckets.Count.Should().BeGreaterThan(0);

var minCommits = response.Aggregations.MinBucket("min_commits_per_month");
minCommits.Should().NotBeNull();
minCommits.Value.Should().BeGreaterThan(0);
minCommits.Keys.Should().NotBeNull();
minCommits.Keys.Count.Should().BeGreaterOrEqualTo(1);
foreach (var key in minCommits.Keys)
    key.Should().NotBeNullOrEmpty();