order api results by descending totalExecTime (with option of adding a query parameter)

codex/rest/api.nim

@@ -195,8 +195,13 @@ proc initDataApi(node: CodexNodeRef, router: var RestRouter) =
     router.api(
       MethodGet,
       "/api/codex/v1/debug/performance") do () -> RestApiResponse:
-        RestApiResponse.response(
-          $(%(getFutureSummaryMetrics())), contentType="application/json")
+        # Returns profiling information, highest totalExecTime first
+
+        without metrics =? sortBy(%(getFutureSummaryMetrics()),
+          "totalExecTime").catch, error:
+            return RestApiResponse.error(Http500, error.msg)
+
+        RestApiResponse.response($(metrics), contentType="application/json")
 
 proc initSalesApi(node: CodexNodeRef, router: var RestRouter) =
   router.api(

codex/utils/asyncprofiler/serialization.nim

@@ -1,5 +1,5 @@
 ## Utilities for serializing profiler metrics.
-
+import std/algorithm
 import std/json
 
 import asyncprofiler
@@ -10,7 +10,7 @@ proc `%`*(o: Duration): JsonNode =
 proc `%`*(o: cstring): JsonNode =
   %($(o))
 
-proc `%`*(o: MetricsSummary): JsonNode =
+proc toJson*(o: MetricsSummary): JsonNode =
   var rows = newJArray()
   for (location, metric) in o.pairs:
     var row = %(metric)
@@ -18,3 +18,11 @@ proc `%`*(o: MetricsSummary): JsonNode =
     rows.add(row)
 
   rows
+
+proc `%`*(o: MetricsSummary): JsonNode = o.toJson()
+
+proc sortBy*(jArray: JsonNode, metric: string): JsonNode {.raises: [ref KeyError].} =
+  %(jArray.getElems.sorted(
+    proc (a, b: JsonNode): int {.raises: [ref KeyError].} =
+      cmp(a[metric].getInt, b[metric].getInt),
+    order=SortOrder.Descending))

tests/codex/utils/asyncprofiler/testserialization.nim

@@ -1,3 +1,4 @@
+import std/sequtils
 import std/tables
 import std/unittest
 import std/json
@@ -14,7 +15,7 @@ checksuite "asyncprofiler utils":
     line: 1
   )
 
-  let metric = OverallMetrics(
+  let fooMetric = OverallMetrics(
     totalExecTime: 2.seconds,
     totalRunTime: 2.seconds,
     totalWallTime: 2.seconds,
@@ -24,7 +25,7 @@ checksuite "asyncprofiler utils":
   )
 
   test "should serialize OverallMetrics":
-    check %metric == %*{
+    check %fooMetric == %*{
       "totalExecTime": 2000000000,
       "totalRunTime": 2000000000,
       "totalWallTime": 2000000000,
@@ -42,7 +43,7 @@ checksuite "asyncprofiler utils":
 
   test "should serialize MetricsSummary":
     var summary: MetricsSummary = {
-      (addr fooLoc): metric
+      (addr fooLoc): fooMetric
     }.toTable
 
     check %summary == %*[%*{
@@ -58,3 +59,30 @@ checksuite "asyncprofiler utils":
       "maxSingleTime": 1500000000,
       "count": 10
     }]
+
+  test "should sort MetricsSummary by the required key":
+    var barLoc = SrcLoc(
+      procedure: "bar",
+      file: "bar.nim",
+      line: 1
+    )
+
+    var barMetrics = OverallMetrics(
+      totalExecTime: 3.seconds,
+      totalRunTime: 1.seconds,
+      totalWallTime: 1.seconds,
+      minSingleTime: 100.nanoseconds,
+      maxSingleTime: 1500.milliseconds,
+      count: 5
+    )
+
+    var summary: MetricsSummary = {
+      (addr fooLoc): fooMetric,
+      (addr barLoc): barMetrics
+    }.toTable
+
+    check (%summary).sortBy("totalExecTime").getElems.map(
+      proc (x: JsonNode): string = x["location"]["procedure"].getStr) == @["bar", "foo"]
+
+    check (%summary).sortBy("count").getElems.map(
+      proc (x: JsonNode): string = x["location"]["procedure"].getStr) == @["foo", "bar"]