Enable Redis and add acceptance tests

Adds the "redis" service and a "tiny" plan to the compose-broker
catalog.json.

Adds a redis endpoint to the healthcheck app and acceptance tests that
deploy and interact with the healthcheck app to ensure redis services
can be provisioned and bound to successfully.

The redigo redis client library was vendored for the healthcheck app.

Author: samcrang

config/service-brokers/compose/catalog.json

@@ -30,7 +30,38 @@
         "databaseType": "mongodb"
       }
     }]
-  },{
+  }, {
+    "id": "1356eeeb-7c5d-4d9d-9a04-c035a2c709b3",
+    "name": "redis",
+    "bindable": true,
+    "description": "Redis instance",
+    "requires": [],
+    "tags": [
+      "redis",
+      "compose"
+    ],
+    "metadata": {
+      "displayName": "Redis",
+      "imageUrl": "https://redis.io/images/redis-logo.svg",
+      "longDescription": "Redis instance",
+      "providerDisplayName": "GOV.UK PaaS",
+      "documentationUrl": "https://compose.com/databases/redis",
+      "supportUrl": "https://www.cloud.service.gov.uk/support.html"
+    },
+    "plans": [{
+      "id": "a8574a4b-9c6c-40ea-a0df-e9b7507948c8",
+      "name": "tiny",
+      "description": "256MB Storage / 256MB RAM",
+      "compose": {
+        "units": 1,
+        "databaseType": "redis"
+      },
+      "metadata": {
+        "displayName": "Redis Tiny",
+        "bullets": []
+      }
+    }]
+  }, {
     "id": "6e9202f2-c2e1-4de8-8d4a-a8c898fc2d8c",
     "name": "elasticsearch",
     "bindable": true,

platform-tests/example-apps/healthcheck/Gopkg.lock

@@ -18,6 +18,7 @@ func main() {
 	http.HandleFunc("/db", dbHandler)
 	http.HandleFunc("/mongo-test", mongoHandler)
 	http.HandleFunc("/elasticsearch-test", elasticsearchHandler)
+	http.HandleFunc("/redis-test", redisHandler)
 	err := http.ListenAndServe(addr, nil)
 	if err != nil {
 		log.Fatal(err)

platform-tests/example-apps/healthcheck/main.go

@@ -0,0 +1,53 @@
+package main
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/garyburd/redigo/redis"
+	"github.com/pkg/errors"
+)
+
+func redisHandler(w http.ResponseWriter, r *http.Request) {
+	err := testRedisConnection()
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+
+	writeJson(w, map[string]interface{}{
+		"success": true,
+	})
+}
+
+func testRedisConnection() error {
+	var credentials struct {
+		URI string `json:"uri"`
+	}
+
+	err := getVCAPServiceCredentials("redis", &credentials)
+	if err != nil {
+		return errors.Wrap(err, "failed to parse VCAP_SERVICES")
+	}
+
+	conn, err := redis.DialURL(credentials.URI)
+	if err != nil {
+		return errors.Wrap(err, "failed to connect to Redis")
+	}
+	defer conn.Close()
+
+	_, err = conn.Do("SET", "hello", "world")
+	if err != nil {
+		return errors.Wrap(err, "failed to SET")
+	}
+
+	redisValue, err := redis.String(conn.Do("GET", "hello"))
+	if err != nil {
+		return errors.Wrap(err, "failed to GET")
+	}
+	if redisValue != "world" {
+		return fmt.Errorf("expected \"world\" got %s", redisValue)
+	}
+
+	return nil
+}