Merge pull request #2 from olaurendeau/config_file

Refactore & Users can define a .tailmq file in their home dir with a list of servers

Author: Olivier Laurendeau

.gitignore

@@ -16,3 +16,4 @@
 bin/
 src/
 pkg/
+build/

Makefile

@@ -1,10 +1,10 @@
-build: gopath gobin install
+build: build-darwin-amd64 build-linux-amd64
 
 install: 
 	go install
 
-gopath: 
-	export GOPATH="$(PWD)"
+build-darwin-amd64:
+	GOOS=darwin GOARCH=amd64 go build -o build/tailmq-darwin-amd64
 
-gobin: 
-	export GOBIN="$(PWD)/bin"
+build-linux-amd64:
+	GOOS=linux GOARCH=amd64 go build -o build/tailmq-linux-amd64

README.md

@@ -3,6 +3,22 @@ Tail messages from a RabbitMQ exchange into your CLI console
 
 # Installation
 
+## Linux
+
+```bash
+curl -O https://github.com/olaurendeau/tailmq/releases/download/v1.0.0/tailmq-linux-amd64
+mv tailmq-linux-amd64 /usr/local/bin/tailmq
+rm tailmq-linux-amd64
+```
+
+## MacOS
+
+```bash
+curl -O https://github.com/olaurendeau/tailmq/releases/download/v1.0.0/tailmq-darwin-amd64
+sudo mv tailmq-darwin-amd64 /usr/local/bin/tailmq
+rm tailmq-darwin-amd64
+```
+
 # Usage examples
 
 Dump messages from an exchange to your console
@@ -35,22 +51,45 @@ $ tailmq amq.topic | grep sent
 
 ```bash
 $ tailmq --help
-NAME:
-   tailmq - Tail a RabbitMQ exchange
+DESCRIPTION
+  TailMQ tail AMQP exchanges and output messages in stdout
+USAGE
+  tailmq [options] <exchange_name>
+EXAMPLES
+  tailmq amp.direct - Tail exchange amp.direct on local server with default access
+  tailmq -uri=amqp://user:[email protected]:5672//awesome amp.topic - Tail exchange amp.topic from server tailmq.com in vhost /awesome
+  tailmq -server=prod amp.fanout - Tail exchange amp.fanout from server prod configured in file ~/.tailmq
+  tailmq -server=prod -vhost=/foobar amp.fanout - Tail exchange amp.fanout from server prod configured in file ~/.tailmq but use vhost /foobar
+OPTIONS
+  -help
+    	How does it work ?
+  -prefix
+    	Should output be prefixed with datetime and time
+  -server string
+    	Use predefined server from configuration
+  -uri string
+    	RabbitMQ amqp uri (default "amqp://guest:guest@localhost:5672/")
+  -verbose
+    	Do you want more informations ?
+  -vhost string
+    	Define vhost to tail from
+```
 
-USAGE:
-   tailmq [global options] command [command options] [exchangeName]
+# Config file
 
-VERSION:
-   0.1.0
+## Format
 
-COMMANDS:
-     help, h  Shows a list of commands or help for one command
+```yaml
+servers:
+    server_name: amqp_uri    
+```
+
+## Sample
 
-GLOBAL OPTIONS:
-   --uri value, -u value  RabbitMQ amqp uri (default: "amqp://guest:guest@localhost:5672/")
-   --prefix               Should output be prefixed with date and time
-   --verbose              Do you want more informations ?
-   --help, -h             show help
-   --version              print only the version
-```
+```yaml
+servers:
+    local: amqp://localhost:5672/
+    staging: amqp://staging.tailmq.io:5672/
+    staging_the_vhost: amqp://staging.tailmq.io:5672/the_vhost
+    prod: amqp://tailmq.io:5672/
+```

config/config.go

@@ -0,0 +1,72 @@
+package consumer
+
+import (
+  "log"
+  "github.com/satori/go.uuid"
+  "github.com/streadway/amqp"
+)
+
+type Consumer struct {
+  uri string
+  exchangeName string
+  conn *amqp.Connection
+  ch *amqp.Channel
+  Deliveries <-chan amqp.Delivery
+  Err chan error
+}
+
+func New(uri string, exchangeName string) *Consumer {
+  c := &Consumer{}
+  c.uri = uri
+  c.exchangeName = exchangeName
+  c.Err = make(chan error)
+
+  return c
+}
+
+func (c *Consumer) Start() () {
+  var err error
+
+  c.conn, c.ch = c.openChannel()
+
+  q := c.createExpirableQueue(c.ch)
+
+  c.Deliveries, err = c.ch.Consume(q.Name, "", true, false, false, false, nil)
+  c.Err <- err
+}
+
+func (c *Consumer) Stop() {
+  c.conn.Close()
+  c.ch.Close()
+}
+
+func (c *Consumer) openChannel() (*amqp.Connection, *amqp.Channel) {
+  log.Printf("Establishing connection... "+ c.uri)
+  conn, err := amqp.Dial(c.uri)
+  c.Err <- err
+  log.Printf("Connected")
+
+  ch, err := conn.Channel()
+  c.Err <- err
+  log.Printf("Channel opened")
+
+  return conn, ch
+}
+
+func (c *Consumer) createExpirableQueue(ch *amqp.Channel) (amqp.Queue) {
+  var args amqp.Table
+  args = make(amqp.Table)
+  args["x-expires"] = int32(10000)
+
+  q, err := ch.QueueDeclare("tailmq_"+uuid.NewV4().String(), false, true, false, false, args)
+  c.Err <- err
+  log.Printf("Queue defined")
+
+  err = ch.QueueBind(q.Name, "#", c.exchangeName, false, nil)
+  c.Err <- err
+  err = ch.QueueBind(q.Name, "", c.exchangeName, false, nil)
+  c.Err <- err
+  log.Printf("Queue " + q.Name + " binded to exchange "+c.exchangeName)
+
+  return q
+}

consumer/consumer.go

@@ -0,0 +1,47 @@
+package main
+
+import (
+  "io/ioutil"
+  "errors"
+  "os/user"
+  
+  "gopkg.in/yaml.v2"
+)
+
+type GlobalConfig struct {
+  Servers map[string]string
+}
+
+func NewGlobalConfig(path string) (GlobalConfig, error) {
+
+  var globalConfig GlobalConfig
+
+  if path == "" {
+    usr, err := user.Current()
+    if err != nil {
+      return globalConfig, err
+    }
+
+    path = usr.HomeDir + "/.tailmq"
+  }
+
+  fileContent, err := ioutil.ReadFile(path)
+
+  if err != nil {
+    return globalConfig, err
+  }
+  
+  err = yaml.Unmarshal(fileContent, &globalConfig)
+
+  return globalConfig, err
+}
+
+func (g GlobalConfig) getServerUri(server string) (string, error) {
+  var err error
+  uri := g.Servers[server]
+  if uri == "" {
+    err = errors.New("No server named " + server)
+  }
+
+  return uri, err
+}