From 768054fab86b9a217b0df543c1fc70b510b894f2 Mon Sep 17 00:00:00 2001
From: Ruben Cervilla <47088081+rbcervilla@users.noreply.github.com>
Date: Mon, 18 Nov 2019 20:48:41 +0100
Subject: [PATCH] Implementation and doc

---
 .gitignore |  5 +++++
 Dockerfile |  8 +++++++
 README.md  | 24 +++++++++++++++++++-
 go.mod     |  5 +++++
 go.sum     | 16 ++++++++++++++
 main.go    | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 122 insertions(+), 1 deletion(-)
 create mode 100644 .gitignore
 create mode 100644 Dockerfile
 create mode 100644 go.mod
 create mode 100644 go.sum
 create mode 100644 main.go

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..15bdab2
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,5 @@
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 0000000..fa6b915
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,8 @@
+FROM golang:1.12.10 as builder
+WORKDIR /build
+COPY . .
+RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -ldflags="-w -s" -o keydb-health
+
+FROM scratch
+COPY --from=builder /build/keydb-health .
+ENTRYPOINT ["/keydb-health"]
\ No newline at end of file
diff --git a/README.md b/README.md
index ca0225e..3fbdeb9 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,24 @@
 # keydb-health
-Health check for KeyDB
+HTTP health check. KeyDB instance is ready to server requests if:
+- Is not loading from persistence
+- Is not synchronizing with master.
+
+### Usage
+
+```
+Usage:
+  -h string
+    	KeyDB host (default "127.0.0.1")
+  -p string
+    	KeyDB port (default "6379")
+  -sp string
+    	Server listener port (default "8080")
+```
+
+### Docker
+
+You can run it with Docker
+
+```sh
+docker run --name keydb-health rbcervilla/keydb-health -h keydbhost -p 6379
+```
\ No newline at end of file
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..39e48ce
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,5 @@
+module github.com/rbcervilla/keydb-health
+
+go 1.12
+
+require github.com/go-redis/redis/v7 v7.0.0-beta.4
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..cf07f8c
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,16 @@
+github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
+github.com/go-redis/redis/v7 v7.0.0-beta.4 h1:p6z7Pde69EGRWvlC++y8aFcaWegyrKHzOBGo0zUACTQ=
+github.com/go-redis/redis/v7 v7.0.0-beta.4/go.mod h1:xhhSbUMTsleRPur+Vgx9sUHtyN33bdjxY+9/0n9Ig8s=
+github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
+github.com/onsi/ginkgo v1.6.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
+github.com/onsi/ginkgo v1.8.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
+github.com/onsi/gomega v1.5.0/go.mod h1:ex+gbHU/CVuBBDIJjb2X0qEXbFg53c61hWP/1CpauHY=
+golang.org/x/net v0.0.0-20180906233101-161cd47e91fd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/fsnotify.v1 v1.4.7/go.mod h1:Tz8NjZHkW78fSQdbUxIjBTcgA1z1m8ZHf0WmKUhAMys=
+gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7/go.mod h1:dt/ZhP58zS4L8KSrWDmTeBkI65Dw0HsyUHuEVlX15mw=
+gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..c2c28cb
--- /dev/null
+++ b/main.go
@@ -0,0 +1,65 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"github.com/go-redis/redis/v7"
+	"net/http"
+	"strings"
+	"time"
+)
+
+func main() {
+
+	h := flag.String("h", "127.0.0.1", "KeyDB host")
+	p := flag.String("p", "6379", "KeyDB port")
+	sp := flag.String("sp", "8080", "Server listener port")
+	flag.Parse()
+
+	client := redis.NewClient(&redis.Options{
+		Addr:        fmt.Sprintf("%s:%s", *h, *p),
+		DialTimeout: time.Second,
+		ReadTimeout: time.Second,
+	})
+
+	http.HandleFunc("/health", func(w http.ResponseWriter, r *http.Request) {
+
+		result, err := client.Info().Result()
+		if err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+
+		info := parseInfo(result)
+		if info["loading"] != "0" || info["master_sync_in_progress"] != "0" {
+			w.WriteHeader(http.StatusInternalServerError)
+			return
+		}
+	})
+
+	if err := http.ListenAndServe(":"+*sp, nil); err != nil {
+		panic(err)
+	}
+}
+
+func parseInfo(str string) map[string]string {
+
+	info := make(map[string]string)
+	lines := strings.Split(str, "\r\n")
+
+	for _, line := range lines {
+
+		if strings.HasPrefix(line, "#") {
+			continue
+		}
+
+		pair := strings.Split(line, ":")
+		if len(pair) != 2 {
+			continue
+		}
+
+		info[pair[0]] = pair[1]
+	}
+
+	return info
+}