From 41f944c23743cf64d633179cbb331f7eafe74de0 Mon Sep 17 00:00:00 2001
From: Hunter Long <info@socialeck.com>
Date: Mon, 5 Nov 2018 17:34:02 -0800
Subject: [PATCH] Docker healthcheck

---
 Dockerfile         |  5 ++++-
 dev/Dockerfile-dev |  5 ++++-
 handlers/index.go  | 10 ++++++++++
 handlers/routes.go |  1 +
 4 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/Dockerfile b/Dockerfile
index 2be8b66c..84bf4892 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,11 +2,14 @@ ARG VERSION
 FROM hunterlong/statup:base-v${VERSION}
 MAINTAINER "Hunter Long (https://github.com/hunterlong)"
 
-# Locked version of Statup for 'latest' Docker tag
+RUN apk --no-cache add curl jq
 ENV IS_DOCKER=true
 ENV STATUP_DIR=/app
 
 WORKDIR /app
 VOLUME /app
 EXPOSE 8080
+
+HEALTHCHECK --interval=5s --timeout=5s --retries=5 CMD curl -s "http://localhost:8080/health" | jq -r -e ".online==true"
+
 CMD ["statup"]
diff --git a/dev/Dockerfile-dev b/dev/Dockerfile-dev
index 81a201e8..5b4e93e0 100644
--- a/dev/Dockerfile-dev
+++ b/dev/Dockerfile-dev
@@ -4,7 +4,7 @@ MAINTAINER "Hunter Long (https://github.com/hunterlong)"
 # Statup 'test' image for running a full test using the production environment
 
 ENV DEP_VERSION=v0.5.0
-RUN apk add --no-cache libstdc++ gcc g++ make git ca-certificates linux-headers wget curl
+RUN apk add --no-cache libstdc++ gcc g++ make git ca-certificates linux-headers wget curl jq
 
 RUN curl -L -s https://github.com/golang/dep/releases/download/$DEP_VERSION/dep-linux-amd64 -o /go/bin/dep && \
     chmod +x /go/bin/dep
@@ -25,4 +25,7 @@ RUN make install
 WORKDIR /app
 VOLUME /app
 EXPOSE 8080
+
+HEALTHCHECK --interval=5s --timeout=5s --retries=5 CMD curl -s "http://localhost:8080/health" | jq -r -e ".online==true"
+
 ENTRYPOINT statup
diff --git a/handlers/index.go b/handlers/index.go
index 3d9ead7c..e108519e 100644
--- a/handlers/index.go
+++ b/handlers/index.go
@@ -16,6 +16,7 @@
 package handlers
 
 import (
+	"encoding/json"
 	"github.com/hunterlong/statup/core"
 	"github.com/hunterlong/statup/types"
 	"github.com/hunterlong/statup/utils"
@@ -30,6 +31,15 @@ func indexHandler(w http.ResponseWriter, r *http.Request) {
 	executeResponse(w, r, "index.html", core.CoreApp, nil)
 }
 
+func healthCheckHandler(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+	health := map[string]interface{}{
+		"services": len(core.Services()),
+		"online":   core.Configs != nil,
+	}
+	json.NewEncoder(w).Encode(health)
+}
+
 func trayHandler(w http.ResponseWriter, r *http.Request) {
 	executeResponse(w, r, "tray.html", core.CoreApp, nil)
 }
diff --git a/handlers/routes.go b/handlers/routes.go
index 0b37c782..eb03e800 100644
--- a/handlers/routes.go
+++ b/handlers/routes.go
@@ -119,6 +119,7 @@ func Router() *mux.Router {
 	r.Handle("/api/notifier/{notifier}", http.HandlerFunc(apiNotifierGetHandler)).Methods("POST")
 
 	r.Handle("/metrics", http.HandlerFunc(prometheusHandler))
+	r.Handle("/health", http.HandlerFunc(healthCheckHandler))
 	r.Handle("/tray", http.HandlerFunc(trayHandler))
 	r.NotFoundHandler = http.HandlerFunc(error404Handler)
 	return r