From ddd3aef3b322f26ffa3459564845f89d9f442302 Mon Sep 17 00:00:00 2001
From: Mark Mulder <markmulder@gmail.com>
Date: Sun, 11 Oct 2015 19:17:53 +0100
Subject: [PATCH] email notification from database

---
 schema.sql      | 10 ++++++++
 single.rb       |  2 +-
 stats.rb        |  6 +++--
 udp_listener.go | 62 ++++++++++++++++++++++++++++---------------------
 4 files changed, 51 insertions(+), 29 deletions(-)

diff --git a/schema.sql b/schema.sql
index cb445a7..d0f7e20 100644
--- a/schema.sql
+++ b/schema.sql
@@ -1,5 +1,15 @@
+-- psql notifier
+-- drop table incoming;
+-- drop table notifiers;
+
 CREATE TABLE incoming(
   id serial primary key,
   received_at timestamp,
   data json
 );
+
+CREATE table notifiers(
+  id serial primary key,
+  class character(256),
+  template text
+)
diff --git a/single.rb b/single.rb
index 0a0b369..fd00153 100644
--- a/single.rb
+++ b/single.rb
@@ -28,5 +28,5 @@ def flush
 
 socket = UDPSocket.new
 s = Stats.new
-message = {mark: 'is cool!'}
+message = {mark: 'is cool!', number: rand(15)}
 s.track({'key' => 'mark', 'value' => message})
diff --git a/stats.rb b/stats.rb
index 9e45362..721fa05 100644
--- a/stats.rb
+++ b/stats.rb
@@ -21,6 +21,7 @@ def track(message)
   def flush
     @backlog.each do |item|
       message = item.to_json
+      puts message
       socket.send(message, 0, "127.0.0.1", 8000)
     end
     @backlog.clear
@@ -32,8 +33,9 @@ def flush
 10.times do
   jobs << Thread.new do
     s = Stats.new
-    100.times do |i|
-      s.track({'key' => 'mark', 'value' => rand(100).to_s})
+    10.times do |i|
+      message = {mark: 'is cool!', number: rand(10)}
+      s.track({'key' => 'mark', 'value' => message})
     end
   end
 end
diff --git a/udp_listener.go b/udp_listener.go
index e8a1932..47ec059 100644
--- a/udp_listener.go
+++ b/udp_listener.go
@@ -1,11 +1,11 @@
 package main
 
 import (
-	"database/sql"
+	// "database/sql"
+	"bytes"
 	"encoding/json"
 	"fmt"
-	// _ "github.com/jmoiron/sqlx"
-	"bytes"
+	"github.com/jmoiron/sqlx"
 	"github.com/jmoiron/sqlx/types"
 	_ "github.com/lib/pq"
 	"log"
@@ -18,7 +18,7 @@ import (
 
 const maxPacketSize = 1024 * 1024
 
-var db *sql.DB
+var db *sqlx.DB
 
 type Stat struct {
 	Key   string         `json:"key"`
@@ -30,6 +30,12 @@ type Notifier struct {
 	Template string
 }
 
+type dbNotifier struct {
+	Id       int    `db:"id"`
+	Class    string `db:"class"`
+	Template string `db:"template"`
+}
+
 func (s *Stat) persist() {
 	var incomingId int
 	err := db.QueryRow(`INSERT INTO incoming(received_at, data) VALUES($1, $2) RETURNING id`, time.Now(), s.Value).Scan(&incomingId)
@@ -40,36 +46,42 @@ func (s *Stat) persist() {
 }
 
 func (s *Stat) notify() {
-	sendEmail(s.Key, string(s.Value))
-}
+	// find (active) notifiers
+	// execute them all
 
-func (s *Stat) specialNotify() {
 	var err error
-	var doc bytes.Buffer
 
-	n := Notifier{
-		"mark",
-		"{{.Number}}: is pretty awesome!, {{.Yeah}} nigga",
+	notifiers := []dbNotifier{}
+	err = db.Select(&notifiers, "SELECT * FROM notifiers WHERE class=$1", s.Key)
+	if err != nil {
+		log.Fatal("db.Select ", err)
+	}
+	fmt.Printf("Found %d notifiers\n", len(notifiers))
+	for i := 0; i < len(notifiers); i++ {
+		s.specialNotify(&notifiers[i])
 	}
+}
+
+func (s *Stat) specialNotify(notifier *dbNotifier) {
+	fmt.Printf("Notifying notifier id: %d\n", notifier.Id)
+	var err error
+	var doc bytes.Buffer
 
 	t := template.New("notificationTemplate")
-	t, err = t.Parse(n.Template)
+	t, err = t.Parse(notifier.Template)
 	if err != nil {
 		log.Fatal("t.Parse of n.Template", err)
 	}
 
-	jmap := map[string]string{
-		"Number": "1000test",
-		"Yeah":   "yeayeah",
-	}
-	err = t.Execute(&doc, jmap)
+	m := map[string]interface{}{}
+	s.Value.Unmarshal(&m)
+
+	err = t.Execute(&doc, m)
 	if err != nil {
 		log.Fatal("t.Execute ", err)
 	}
 
-	fmt.Println(doc)
-	sendEmail(s.Key, string(doc.Bytes()))
-
+	sendEmail(s.Key, doc.Bytes())
 }
 
 func countRows() int {
@@ -102,8 +114,7 @@ func listenToUDP(conn *net.UDPConn) {
 		}
 
 		stat.persist()
-		// stat.notify()
-		stat.specialNotify()
+		stat.notify()
 	}
 }
 
@@ -144,7 +155,7 @@ type EmailData struct {
 	Body    string
 }
 
-func sendEmail(class string, data string) {
+func sendEmail(class string, data []byte) {
 	var err error
 	var doc bytes.Buffer
 
@@ -153,12 +164,11 @@ func sendEmail(class string, data string) {
 	if err != nil {
 		log.Fatal("t.Parse ", err)
 	}
-	// bodyString := fmt.Sprintf("<h1>class: %s</h1>\\n<p>data: %s</p>", class, data)
 	context := &EmailData{
 		"Springest Dev <developers@springest.nl>",
 		"recipient@example.com",
 		"Email subject line",
-		data,
+		string(data),
 	}
 	err = t.Execute(&doc, context)
 	if err != nil {
@@ -182,7 +192,7 @@ func main() {
 		log.Fatal("ListenUDP", err)
 	}
 
-	db, err = sql.Open("postgres", "user=markmulder dbname=notifier sslmode=disable")
+	db, err = sqlx.Connect("postgres", "user=markmulder dbname=notifier sslmode=disable")
 	if err != nil {
 		log.Fatal("DB Open()", err)
 	}