From a8d7458a0f57e9e8d249d3dc561a73d5dc74560c Mon Sep 17 00:00:00 2001
From: Andrii Vorobiov <and.vorobiov@gmail.com>
Date: Wed, 12 Jan 2022 16:45:38 +0200
Subject: [PATCH] server: nit. add details comments for hot range V2 functions
 and proto messages

Provide more detailed descriptions on implemented functions and
proto messages related to Hot Ranges functionality.

Release note: None
---
 docs/generated/http/full.md      | 4 ++--
 pkg/server/api_v2_ranges.go      | 3 ++-
 pkg/server/serverpb/status.proto | 2 ++
 pkg/server/status.go             | 3 ++-
 4 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/docs/generated/http/full.md b/docs/generated/http/full.md
index ff6f23638106..2497cfb42cff 100644
--- a/docs/generated/http/full.md
+++ b/docs/generated/http/full.md
@@ -3128,7 +3128,7 @@ of ranges currently considered “hot” by the node(s).
 
 
 
-
+HotRangesResponseV2 is a response payload returned by `HotRangesV2` service.
 
 
 | Field | Type | Label | Description | Support status |
@@ -3143,7 +3143,7 @@ of ranges currently considered “hot” by the node(s).
 <a name="cockroach.server.serverpb.HotRangesResponseV2-cockroach.server.serverpb.HotRangesResponseV2.HotRange"></a>
 #### HotRangesResponseV2.HotRange
 
-
+HotRange message describes a single hot range, ie its QPS, node ID it belongs to, etc.
 
 | Field | Type | Label | Description | Support status |
 | ----- | ---- | ----- | ----------- | -------------- |
diff --git a/pkg/server/api_v2_ranges.go b/pkg/server/api_v2_ranges.go
index f0db6dbbaac8..0ff70a432079 100644
--- a/pkg/server/api_v2_ranges.go
+++ b/pkg/server/api_v2_ranges.go
@@ -421,7 +421,8 @@ type hotRangesResponse struct {
 	Next string `json:"next,omitempty"`
 }
 
-// Hot range details
+// Hot range details struct describes common information about hot range,
+// (ie its range ID, QPS, table name, etc.).
 //
 // swagger:model hotRangeInfo
 type hotRangeInfo struct {
diff --git a/pkg/server/serverpb/status.proto b/pkg/server/serverpb/status.proto
index 77c0dab9b3fd..383eb53055d7 100644
--- a/pkg/server/serverpb/status.proto
+++ b/pkg/server/serverpb/status.proto
@@ -1122,7 +1122,9 @@ message HotRangesResponse {
   ];
 }
 
+// HotRangesResponseV2 is a response payload returned by `HotRangesV2` service.
 message HotRangesResponseV2 {
+  // HotRange message describes a single hot range, ie its QPS, node ID it belongs to, etc.
   message HotRange {
     // range_id indicates Range ID that's identified as hot range
     int32 range_id = 1 [
diff --git a/pkg/server/status.go b/pkg/server/status.go
index e0097b755121..2513938d130b 100644
--- a/pkg/server/status.go
+++ b/pkg/server/status.go
@@ -2069,6 +2069,8 @@ type hotRangeReportMeta struct {
 	parentId   uint32
 }
 
+// HotRangesV2 returns hot ranges from all stores on requested node or all nodes in case
+// request message doesn't include specific node ID.
 func (s *statusServer) HotRangesV2(
 	ctx context.Context, req *serverpb.HotRangesRequest,
 ) (*serverpb.HotRangesResponseV2, error) {
@@ -2109,7 +2111,6 @@ func (s *statusServer) HotRangesV2(
 	}
 
 	var ranges []*serverpb.HotRangesResponseV2_HotRange
-	// TODO (koorosh): how to flatten triple nested loop?
 	for nodeID, hr := range resp.HotRangesByNodeID {
 		for _, store := range hr.Stores {
 			for _, r := range store.HotRanges {