From ea157766d91a5bcc61598fe3e1c1c4260ce7fe19 Mon Sep 17 00:00:00 2001
From: "Jorge S. Cuesta" <jckpo2@gmail.com>
Date: Wed, 12 Oct 2022 10:48:04 -0400
Subject: [PATCH] Added /v1/health endpoint and update rpc spec.

---
 app/cmd/rpc/query.go    | 10 ++++++++++
 app/cmd/rpc/server.go   |  1 +
 app/query.go            | 31 +++++++++++++++++++++++++++++++
 doc/specs/rpc-spec.yaml | 25 +++++++++++++++++++++++++
 4 files changed, 67 insertions(+)

diff --git a/app/cmd/rpc/query.go b/app/cmd/rpc/query.go
index e6f06bdb0..a26c2d775 100644
--- a/app/cmd/rpc/query.go
+++ b/app/cmd/rpc/query.go
@@ -27,6 +27,16 @@ func Version(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
 	WriteResponse(w, APIVersion, r.URL.Path, r.Host)
 }
 
+func Health(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
+	res := app.PCA.QueryHealth(APIVersion)
+	j, er := json.Marshal(res)
+	if er != nil {
+		WriteErrorResponse(w, 400, er.Error())
+		return
+	}
+	WriteJSONResponse(w, string(j), r.URL.Path, r.Host)
+}
+
 func LocalNodes(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
 	value := r.URL.Query().Get("authtoken")
 	if value != app.AuthToken.Value {
diff --git a/app/cmd/rpc/server.go b/app/cmd/rpc/server.go
index 2c1493272..c63ae3d66 100644
--- a/app/cmd/rpc/server.go
+++ b/app/cmd/rpc/server.go
@@ -87,6 +87,7 @@ type Routes []Route
 func GetRoutes() Routes {
 	routes := Routes{
 		Route{Name: "AppVersion", Method: "GET", Path: "/v1", HandlerFunc: Version},
+		Route{Name: "Health", Method: "GET", Path: "/v1/health", HandlerFunc: Health},
 		Route{Name: "Challenge", Method: "POST", Path: "/v1/client/challenge", HandlerFunc: Challenge},
 		Route{Name: "ChallengeCORS", Method: "OPTIONS", Path: "/v1/client/challenge", HandlerFunc: Challenge},
 		Route{Name: "HandleDispatch", Method: "POST", Path: "/v1/client/dispatch", HandlerFunc: Dispatch},
diff --git a/app/query.go b/app/query.go
index ea966919b..0f7106833 100644
--- a/app/query.go
+++ b/app/query.go
@@ -29,6 +29,37 @@ const (
 	txHeightQuery          = "tx.height=%d"
 )
 
+type HealthResponse struct {
+	Version      string `json:"version"`
+	IsStarting   bool   `json:"is_starting"`
+	IsCatchingUp bool   `json:"is_catching_up"`
+	Height       int64  `json:"height"`
+}
+
+func (app PocketCoreApp) QueryHealth(version string) (res HealthResponse) {
+	res = HealthResponse{
+		Version:      version,
+		IsStarting:   true,
+		IsCatchingUp: false,
+		Height:       0,
+	}
+	res.Height = app.LastBlockHeight()
+	_, err := app.NewContext(res.Height)
+
+	if err != nil {
+		return
+	}
+
+	status, sErr := app.pocketKeeper.TmNode.ConsensusReactorStatus()
+	if sErr != nil {
+		return
+	}
+
+	res.IsStarting = false
+	res.IsCatchingUp = status.IsCatchingUp
+	return
+}
+
 // zero for height = latest
 func (app PocketCoreApp) QueryBlock(height *int64) (blockJSON []byte, err error) {
 	tmClient := app.GetClient()
diff --git a/doc/specs/rpc-spec.yaml b/doc/specs/rpc-spec.yaml
index 286dae637..8f95eacc4 100644
--- a/doc/specs/rpc-spec.yaml
+++ b/doc/specs/rpc-spec.yaml
@@ -17,6 +17,8 @@ servers:
 tags:
   - name: version
     description: Version of the Pocket API
+  - name: health
+    description: Health of the Pocket Node
   - name: client
     description: Dispatch and relay services
   - name: query
@@ -35,6 +37,18 @@ paths:
               schema:
                 type: string
                 example: 0.0.1
+  /health:
+    get:
+      tags:
+        - health
+      summary: Get current node version, height, starting and running state
+      responses:
+        '200':
+          description: Health status of the node
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Health'
   /client/dispatch:
     post:
       tags:
@@ -1464,6 +1478,17 @@ components:
       properties:
         address:
           type: string
+    Health:
+      type: object
+      properties:
+        version:
+          type: string
+        height:
+          type: integer
+        is_starting:
+          type: boolean
+        is_catching_up:
+          type: boolean
     Chain:
       type: object
       properties: