Load config file via AWS S3 closes #58 (#60)

* Load config file via AWS S3 closes #58

* Add AWS client deps

README.md

@@ -131,17 +131,25 @@ Available Commands:
 Flags:
   -d, --config-db string     config database url
   -f, --config-file string   config file (default "config.json")
+  -s, --config-s3 string     config S3
+  -u, --config-url string    config url
   -h, --help                 help for redalert
   -p, --port int             port to run web server (default 8888)
   -r, --rpc-port int         port to run RPC server (default 8889)
 
 Use "redalert [command] --help" for more information about a command.
 ```
 
-#### Monitoring Configuration
-Configure servers to monitor & alert settings via `config.json`.
+#### Configuration
 
-##### Simple config.json
+Configure servers to monitor & alert settings via a configuration file:
+* a local file (specified by `-f` or `--config-file`) - defaults to `config.json`
+* a file remotely accessible via HTTP (specified by `-u` or `--config-url`)
+* a file hosted in an AWS S3 bucket (specified by `-s` or `--config-s3`)
+
+TODO: document Postgres configuration option
+
+##### Example config.json
 ```
 {
    "checks":[

cmd/root.go

@@ -42,6 +42,7 @@ func Execute() {
 var cfgFile string
 var cfgDb string
 var cfgURL string
+var cfgS3 string
 var webPort int
 var rpcPort int
 var disableBrand bool
@@ -50,6 +51,7 @@ func init() {
 	RootCmd.PersistentFlags().StringVarP(&cfgFile, "config-file", "f", "config.json", "config file")
 	RootCmd.PersistentFlags().StringVarP(&cfgDb, "config-db", "d", "", "config database url")
 	RootCmd.PersistentFlags().StringVarP(&cfgURL, "config-url", "u", "", "config url")
+	RootCmd.PersistentFlags().StringVarP(&cfgS3, "config-s3", "s", "", "config S3")
 	RootCmd.PersistentFlags().IntVarP(&webPort, "port", "p", 8888, "port to run web server")
 	RootCmd.PersistentFlags().IntVarP(&rpcPort, "rpc-port", "r", 8889, "port to run RPC server")
 }

cmd/server.go

@@ -40,6 +40,13 @@ var serverCmd = &cobra.Command{
 			if err != nil {
 				log.Fatal("URL config error via :", configURL, " Error: ", err)
 			}
+		} else if cmd.Flag("config-s3").Changed {
+			log.Println("Config via S3")
+			configS3 := cmd.Flag("config-s3").Value.String()
+			configStore, err = config.NewS3Store(configS3)
+			if err != nil {
+				log.Fatal("S3 config error via :", configS3, " Error: ", err)
+			}
 		} else {
 			log.Println("Config via file")
 			configFile := cmd.Flag("config-file").Value.String()

config/s3_store.go

@@ -0,0 +1,102 @@
+package config
+
+import (
+	"bytes"
+	"encoding/json"
+	"io"
+	"log"
+	"net/url"
+
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/session"
+	"github.com/aws/aws-sdk-go/service/s3"
+	"github.com/jonog/redalert/checks"
+	"github.com/jonog/redalert/notifiers"
+)
+
+type S3Store struct {
+	URL  string
+	data S3StoreData
+}
+
+type S3StoreData struct {
+	Checks        []checks.Config    `json:"checks"`
+	Notifications []notifiers.Config `json:"notifications"`
+	Preferences   Preferences        `json:"preferences"`
+}
+
+func NewS3Store(URL string) (*S3Store, error) {
+	config := &S3Store{URL: URL}
+	err := config.read()
+	if err != nil {
+		return nil, err
+	}
+
+	// create check ID if not present
+	for i := range config.data.Checks {
+		if config.data.Checks[i].ID == "" {
+			config.data.Checks[i].ID = generateID(8)
+		}
+	}
+
+	// create notification ID if not present
+	for i := range config.data.Notifications {
+		if config.data.Notifications[i].ID == "" {
+			config.data.Notifications[i].ID = generateID(8)
+		}
+	}
+
+	return config, nil
+}
+
+func (s *S3Store) read() error {
+
+	u, err := url.Parse(s.URL)
+	if err != nil {
+		return err
+	}
+	log.Printf("bucket: %q, key: %q", u.Host, u.Path)
+
+	sess := session.Must(session.NewSession())
+	body, err := getS3File(sess, u.Host, u.Path)
+	if err != nil {
+		return err
+	}
+
+	var data S3StoreData
+	err = json.Unmarshal(body, &data)
+	if err != nil {
+		return err
+	}
+	s.data = data
+	return nil
+}
+
+func getS3File(s *session.Session, bucket, key string) (value []byte, err error) {
+	results, err := s3.New(s).GetObject(&s3.GetObjectInput{
+		Bucket: aws.String(bucket),
+		Key:    aws.String(key),
+	})
+	if err != nil {
+		return nil, err
+	}
+	defer results.Body.Close()
+
+	buf := bytes.NewBuffer(nil)
+	if _, err := io.Copy(buf, results.Body); err != nil {
+		return nil, err
+	}
+	return buf.Bytes(), nil
+}
+
+func (s *S3Store) Notifications() ([]notifiers.Config, error) {
+	return s.data.Notifications, nil
+}
+
+func (s *S3Store) Checks() ([]checks.Config, error) {
+	return s.data.Checks, nil
+}
+
+func (s *S3Store) Preferences() (Preferences, error) {
+	return s.data.Preferences, nil
+}

glide.yaml

@@ -29,6 +29,12 @@ import:
 - package: google.golang.org/grpc
   version: ^1.0.5
 - package: gopkg.in/gorp.v1
+- package: github.com/aws/aws-sdk-go
+  version: ^1.12.10
+  subpackages:
+  - aws
+  - aws/session
+  - service/s3
 testImport:
 - package: github.com/docker/go-connections
   subpackages:

uploaded_config.json

@@ -0,0 +1,30 @@
+{
+  "checks": [
+    {
+      "name": "AWS Bravo Adapter",
+      "type": "web-ping",
+      "send_alerts": [
+        "stderr"
+      ],
+      "backoff": {
+        "type": "constant",
+        "interval": 10
+      },
+      "config": {
+        "address": "https://uat01.webapi.tab.com.au/v1/bravo-adapter/status"
+      },
+      "assertions": [
+        {
+          "source": "metadata",
+          "identifier": "status_code",
+          "comparison": "==",
+          "target": "200"
+        }
+      ]
+    }
+  ],
+  "notifications": [],
+  "preferences": {
+    "notifications": {}
+  }
+}