Refactor config to be more structured (#54)

README.md

@@ -111,43 +111,7 @@ Instances that are listening will produce output when they receive messages.
 Configuration is available through command line flags, a configuration file,
 and/or environment variables.
 
-#### Configuration File
-
-A configuration file can be provided. This is useful when trying to template
-configuration such as with Consul or similar tools.
-
-A full configuration file with all options is given below.
-
-```yaml
-# my-cyn-config.yaml
-listen-udp:
-  - 192.168.58.4:2345
-listen-tcp:
-  - 192.168.58.4:2346
-send-udp:
-  - 192.168.58.3:1234
-send-tcp:
-  - 192.168.58.3:1235
-send-interval: 30s
-send-data: "my-custom-data"
-http:
-  address: 127.0.0.1:8080
-sinks:
-  stdout:
-    enabled: true
-```
-
-The configuration file must be supplied with the `--config/-c` command line
-flag.
-
-```bash
-cyn --config ./my-cyn-config.yaml
-
-# Can also use -c for shorthand
-cyn -c ./my-cyn-config.yaml
-```
-
-### Command line flags
+#### Command line flags
 
 All available flags can be seen by running `cyn --help`. This README snippet should
 have the latest, but when in doubt, just run the command to check.
@@ -163,30 +127,68 @@ Available Commands:
   version     Displays the version
 
 Flags:
-  -c, --config-file string       A file path to load as additional configuration.
+  -c, --config string            A file path to load as additional configuration.
   -h, --help                     help for this command
       --http.address string      An address:port to host an HTTP server on for realtime data, such as '127.0.0.1:8080'
-  -t, --listen-tcp strings       An IP:port address to listen on for TCP.  Can be specified multiple times.
-  -u, --listen-udp strings       An IP:port address to listen on for UDP.  Can be specified multiple times.
-  -d, --send-data string         The string data to send. (default "hi")
-  -i, --send-interval duration   How long to wait between attempting to send data (default 1s)
-  -T, --send-tcp strings         An IP:port address to send to (TCP).  Can be specified multiple times.
-  -U, --send-udp strings         An IP:port address to send to (UDP).  Can be specified multiple times.
+  -t, --listen.tcp strings       An IP:port address to listen on for TCP.  Can be specified multiple times.
+  -u, --listen.udp strings       An IP:port address to listen on for UDP.  Can be specified multiple times.
+  -d, --send.data string         The string data to send. (default "hi")
+  -i, --send.interval duration   How long to wait between attempting to send data (default 1s)
+  -T, --send.tcp strings         An IP:port address to send to (TCP).  Can be specified multiple times.
+  -U, --send.udp strings         An IP:port address to send to (UDP).  Can be specified multiple times.
       --sinks.stdout.enabled     Whether to enable the stdout metrics sink
 
 Use " [command] --help" for more information about a command.
 ```
 
-### Environment variables
+#### Environment variables
 
 Configuration can be supplied throuh environment variables that follow the
-`CYNOMYS_VAR_NAME` pattern, replacing `-` with `_`. For example:
+`CYNOMYS_VAR_NAME` pattern, replacing `.` with `_`. For example:
 
 ```bash
 export CYNOMYS_SEND_INTERVAL=500ms
 cyn -T 192.168.58.3:1234
 ```
 
+#### Configuration File
+
+A configuration file can be provided. This is useful when trying to template
+configuration such as with Consul or similar tools.
+
+A full configuration file with all options is given below.
+
+```yaml
+# my-cyn-config.yaml
+listen:
+  udp:
+    - 192.168.58.4:2345
+  tcp:
+    - 192.168.58.4:2346
+send:
+  udp:
+    - 192.168.58.3:1234
+  tcp:
+    - 192.168.58.3:1235
+  interval: 30s
+  data: "my custom data"
+http:
+  address: 127.0.0.1:8080
+sinks:
+  stdout:
+    enabled: true
+```
+
+The configuration file must be supplied with the `--config/-c` command line
+flag.
+
+```bash
+cyn --config ./my-cyn-config.yaml
+
+# Can also use -c for shorthand
+cyn -c ./my-cyn-config.yaml
+```
+
 ## Why the name
 
 [Prarie dogs talk to each other](https://en.wikipedia.org/wiki/Prairie_dog)

cmd/cyn/cmds/root.go

@@ -17,13 +17,20 @@ import (
 )
 
 var config struct {
-	ListenUDP    []string      `mapstructure:"listen-udp"`
-	ListenTCP    []string      `mapstructure:"listen-tcp"`
-	SendUDP      []string      `mapstructure:"send-udp"`
-	SendTCP      []string      `mapstructure:"send-tcp"`
-	SendInterval time.Duration `mapstructure:"send-interval"`
-	SendData     string        `mapstructure:"send-data"`
-	HTTPServer   struct {
+	Listen struct {
+		Udp []string `mapstructure:"udp"`
+		Tcp []string `mapstructure:"tcp"`
+	} `mapstructure:"listen"`
+
+	Send struct {
+		Udp []string `mapstructure:"udp"`
+		Tcp []string `mapstructure:"tcp"`
+
+		Interval time.Duration `mapstructure:"interval"`
+		Data     string        `mapstructure:"data"`
+	} `mapstructure:"send"`
+
+	HTTPServer struct {
 		Address string `mapstructure:"address"`
 	} `mapstructure:"http"`
 
@@ -44,14 +51,14 @@ func init() {
 	flags := rootCmd.Flags()
 
 	// Special flag for config
-	flags.StringVarP(&configFilePath, "config-file", "c", "", "A file path to load as additional configuration.")
-
-	flags.StringSliceP("listen-udp", "u", nil, "An IP:port address to listen on for UDP.  Can be specified multiple times.")
-	flags.StringSliceP("listen-tcp", "t", nil, "An IP:port address to listen on for TCP.  Can be specified multiple times.")
-	flags.StringSliceP("send-udp", "U", nil, "An IP:port address to send to (UDP).  Can be specified multiple times.")
-	flags.StringSliceP("send-tcp", "T", nil, "An IP:port address to send to (TCP).  Can be specified multiple times.")
-	flags.StringP("send-data", "d", "hi", "The string data to send.")
-	flags.DurationP("send-interval", "i", time.Second, "How long to wait between attempting to send data")
+	flags.StringVarP(&configFilePath, "config", "c", "", "A file path to load as additional configuration.")
+
+	flags.StringSliceP("listen.udp", "u", nil, "An IP:port address to listen on for UDP.  Can be specified multiple times.")
+	flags.StringSliceP("listen.tcp", "t", nil, "An IP:port address to listen on for TCP.  Can be specified multiple times.")
+	flags.StringSliceP("send.udp", "U", nil, "An IP:port address to send to (UDP).  Can be specified multiple times.")
+	flags.StringSliceP("send.tcp", "T", nil, "An IP:port address to send to (TCP).  Can be specified multiple times.")
+	flags.StringP("send.data", "d", "hi", "The string data to send.")
+	flags.DurationP("send.interval", "i", time.Second, "How long to wait between attempting to send data")
 	flags.String("http.address", "", "An address:port to host an HTTP server on for realtime data, such as '127.0.0.1:8080'")
 	flags.Bool("sinks.stdout.enabled", false, "Whether to enable the stdout metrics sink")
 
@@ -68,7 +75,7 @@ func initConfig() {
 	}
 
 	viper.SetEnvPrefix("CYNOMYS")
-	viper.SetEnvKeyReplacer(strings.NewReplacer("-", "_"))
+	viper.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
 	viper.AutomaticEnv()
 
 	// Ignore errors here because we don't necessarily need a config file
@@ -99,7 +106,7 @@ var rootCmd = &cobra.Command{
 			instance.AddHTTPServer(config.HTTPServer.Address)
 		}
 
-		for _, listenOnUDP := range config.ListenUDP {
+		for _, listenOnUDP := range config.Listen.Udp {
 			addr, err := net.ResolveUDPAddr("udp", listenOnUDP)
 
 			if err != nil {
@@ -109,7 +116,7 @@ var rootCmd = &cobra.Command{
 			instance.AddUDPListener(listener.NewUDP(*addr))
 		}
 
-		for _, listenOnTCP := range config.ListenTCP {
+		for _, listenOnTCP := range config.Listen.Tcp {
 			addr, err := net.ResolveTCPAddr("tcp", listenOnTCP)
 
 			if err != nil {
@@ -119,26 +126,26 @@ var rootCmd = &cobra.Command{
 			instance.AddTCPListener(listener.NewTCP(*addr))
 		}
 
-		for _, sendUDPTo := range config.SendUDP {
+		for _, sendUDPTo := range config.Send.Udp {
 			addr, err := net.ResolveUDPAddr("udp", sendUDPTo)
 
 			if err != nil {
 				return fmt.Errorf("net.ResolveUDPAddr for %q: %w", sendUDPTo, err)
 			}
 
-			instance.AddUDPSender(sender.NewUDPSender(*addr, config.SendInterval, sink, []byte(config.SendData)))
+			instance.AddUDPSender(sender.NewUDPSender(*addr, config.Send.Interval, sink, []byte(config.Send.Data)))
 		}
 
 		// We could probably generalize this a bit better, but it's short enough
 		// not to care for now.
-		for _, sendTCPTo := range config.SendTCP {
+		for _, sendTCPTo := range config.Send.Tcp {
 			addr, err := net.ResolveTCPAddr("tcp", sendTCPTo)
 
 			if err != nil {
 				return fmt.Errorf("net.ResolveTCPAddr for %q: %w", sendTCPTo, err)
 			}
 
-			instance.AddTCPSender(sender.NewTCPSender(*addr, config.SendInterval, sink, []byte(config.SendData)))
+			instance.AddTCPSender(sender.NewTCPSender(*addr, config.Send.Interval, sink, []byte(config.Send.Data)))
 		}
 
 		return instance.Run()

tests/features/http-server.feature

@@ -4,7 +4,7 @@ Feature: host HTTP server for live status
   So that I can visually check if data is flowing
 
   Scenario: http server is enabled
-    Given I run cyn --listen-tcp 127.0.0.1:24184 --http.address 127.0.0.1:24185 --listen-udp 127.0.0.1:24183
+    Given I run cyn --listen.tcp 127.0.0.1:24184 --http.address 127.0.0.1:24185 --listen.udp 127.0.0.1:24183
     And I wait a moment
     # TODO: better verification, this is quick and dirty for now
     Then the page at http://127.0.0.1:24185 contains "table"

tests/features/listen-tcp.feature

@@ -3,18 +3,18 @@ Feature: listen for TCP
   Cyn should accept incoming TCP connections
 
   Scenario: nothing is sent
-    Given I run cyn --listen-tcp 127.0.0.1:24563
+    Given I run cyn --listen.tcp 127.0.0.1:24563
     When I wait 1 second
     Then there is no output
 
   Scenario: a TCP connection is made with no data sent
-    Given I run cyn --listen-tcp 127.0.0.1:24564
+    Given I run cyn --listen.tcp 127.0.0.1:24564
     When I connect with TCP to 127.0.0.1:24564
     And I wait a moment
     Then the stdout contains "TCP connected"
 
   Scenario: a TCP connection is made and then disconnected
-    Given I run cyn --listen-tcp 127.0.0.1:24565
+    Given I run cyn --listen.tcp 127.0.0.1:24565
     When I connect with TCP to 127.0.0.1:24565
     And I wait a moment
     And I disconnect my TCP connection
@@ -30,11 +30,12 @@ Feature: listen for TCP
     Then the stdout contains "TCP connected"
     And the stdout contains "my tcp stuff"
 
-  Scenario: the listener is set via config file
+  Scenario: the tcp listener is set via config file
     Given a configuration file that contains:
       """
-      listen-tcp:
-        - 127.0.0.1:14568
+      listen:
+        tcp:
+          - 127.0.0.1:14568
       """
     And cyn is started with the config file
     When I connect with TCP to 127.0.0.1:14568

tests/features/listen-udp.feature

@@ -4,12 +4,12 @@ Feature: listen for UDP
 
   Scenario: nothing is sent
     #Given cyn is listening for UDP on 127.0.0.1:14563
-    Given I run cyn --listen-udp 127.0.0.1:14563
+    Given I run cyn --listen.udp 127.0.0.1:14563
     When I wait 1 second
     Then there is no output
 
   Scenario: a single UDP packet is sent
-    Given I run cyn --listen-udp 127.0.0.1:14564
+    Given I run cyn --listen.udp 127.0.0.1:14564
     When I send a UDP packet containing "hello" to 127.0.0.1:14564
     Then the stdout contains "hello"
 
@@ -20,11 +20,12 @@ Feature: listen for UDP
     Then the stdout contains "hello"
     And the stdout contains "another"
 
-  Scenario: the listener is set via config file
+  Scenario: the udp listener is set via config file
     Given a configuration file that contains:
       """
-      listen-udp:
-        - 127.0.0.1:14568
+      listen:
+        udp:
+          - 127.0.0.1:14568
       """
     And cyn is started with the config file
     When I send a UDP packet containing "hello" to 127.0.0.1:14568

tests/features/sink-stdout.feature

@@ -4,22 +4,23 @@ Feature: watch latency in stdout
 
   Scenario: no latency in stdout by default
     Given I run cyn -u 127.0.0.1:14567
-    And I run cyn -U 127.0.0.1:14567 --send-interval 200ms
+    And I run cyn -U 127.0.0.1:14567 --send.interval 200ms
     When I wait 1 second
     Then the stdout does not contain "latency"
 
   Scenario: latency is displayed in stdout when asked for
     Given I run cyn -u 127.0.0.1:14567
-    And I run cyn -U 127.0.0.1:14567 --send-interval 200ms --sinks.stdout.enabled
+    And I run cyn -U 127.0.0.1:14567 --send.interval 200ms --sinks.stdout.enabled
     When I wait 1 second
     Then the stdout contains "latency"
 
   Scenario: latency is displayed in stdout when configured via file
     Given a configuration file that contains:
       """
-      send-udp:
-        - 127.0.0.1:14567
-      send-interval: 10ms
+      send:
+        interval: 10ms
+        udp:
+          - 127.0.0.1:14567
       sinks:
         stdout:
           enabled: true

tests/features/tcp.feature

@@ -3,7 +3,7 @@ Feature: send and receive TCP
   Cyn should both send and receive on TCP connections
 
   Scenario: one tries to connect to nothing
-    Given I run cyn --send-tcp 127.0.0.1:1234
+    Given I run cyn --send.tcp 127.0.0.1:1234
     When I wait a moment
     Then the stdout contains "connection refused"
 
@@ -34,14 +34,16 @@ Feature: send and receive TCP
     And I wait 1 second
     Then the stdout does not contain "broken pipe"
 
-  Scenario: an instance is set to call itself via config file
+  Scenario: a tcp instance is set to call itself via config file
     Given a configuration file that contains:
       """
-      listen-tcp:
-        - 127.0.0.1:24568
-      send-tcp:
-        - 127.0.0.1:24568
-      send-interval: 10ms
+      listen:
+        tcp:
+          - 127.0.0.1:24568
+      send:
+        interval: 10ms
+        tcp:
+          - 127.0.0.1:24568
       """
     When cyn is started with the config file
     And I wait 1 second
@@ -50,10 +52,12 @@ Feature: send and receive TCP
   Scenario: an instance is set to call itself via config file and the send interval is set via env variable
     Given a configuration file that contains:
       """
-      listen-tcp:
-        - 127.0.0.1:24568
-      send-tcp:
-        - 127.0.0.1:24568
+      listen:
+        tcp:
+          - 127.0.0.1:24568
+      send:
+        tcp:
+          - 127.0.0.1:24568
       """
     And the environment variable CYNOMYS_SEND_INTERVAL is set to "10ms"
     When cyn is started with the config file