[Bugfix] When multiple host is specified, one port/protocol can't be specified

config/configuration.go

@@ -2,6 +2,7 @@ package config
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"log"
 	"reflect"
@@ -46,7 +47,7 @@ func getDefaultEnvConfig() *EnvConfig {
 }
 
 // Load method loads the configuration by using both flag or environment variables.
-func Load() (*EnvConfig, []Config) {
+func Load() (*EnvConfig, []Config, error) {
 	loaders := []backend.Backend{
 		env.NewBackend(),
 		flags.NewBackend(),
@@ -62,7 +63,11 @@ func Load() (*EnvConfig, []Config) {
 
 	cfg.show()
 
-	return cfg, cfg.Split()
+	if clientsConfig, err := cfg.Split(); err != nil {
+		return cfg, nil, err
+	} else {
+		return cfg, clientsConfig, nil
+	}
 }
 
 func (c *Config) String() string {
@@ -87,43 +92,64 @@ func (c Config) Validate() error {
 	return nil
 }
 
-func (c EnvConfig) Split() []Config {
-	result := make([]Config, 0, len(c.PIHoleHostname))
+func (c EnvConfig) Split() ([]Config, error) {
+	hostsCount := len(c.PIHoleHostname)
+	result := make([]Config, 0, hostsCount)
 
 	for i, hostname := range c.PIHoleHostname {
 		config := Config{
-			PIHoleHostname: hostname,
-			PIHoleProtocol: c.PIHoleProtocol[i],
-			PIHolePort:     c.PIHolePort[i],
+			PIHoleHostname: strings.TrimSpace(hostname),
+		}
+
+		if len(c.PIHolePort) == 1 {
+			config.PIHolePort = c.PIHolePort[0]
+		} else if len(c.PIHolePort) == hostsCount {
+			config.PIHolePort = c.PIHolePort[i]
+		} else if len(c.PIHolePort) != 0 {
+			return nil, errors.New("Wrong number of ports. Port can be empty to use default, one value to use for all hosts, or match the number of hosts")
 		}
 
-		if c.PIHoleApiToken != nil {
-			if len(c.PIHoleApiToken) == 1 {
-				if c.PIHoleApiToken[0] != "" {
-					config.PIHoleApiToken = c.PIHoleApiToken[0]
-				}
-			} else if len(c.PIHoleApiToken) > 1 {
-				if c.PIHoleApiToken[i] != "" {
-					config.PIHoleApiToken = c.PIHoleApiToken[i]
-				}
-			}
+		if hasData, data, isValid := extractStringConfig(c.PIHoleProtocol, i, hostsCount); hasData {
+			config.PIHoleProtocol = data
+		} else if !isValid {
+			return nil, errors.New("Wrong number of PIHoleProtocol. PIHoleProtocol can be empty to use default, one value to use for all hosts, or match the number of hosts")
 		}
 
-		if c.PIHolePassword != nil {
-			if len(c.PIHolePassword) == 1 {
-				if c.PIHolePassword[0] != "" {
-					config.PIHolePassword = c.PIHolePassword[0]
-				}
-			} else if len(c.PIHolePassword) > 1 {
-				if c.PIHolePassword[i] != "" {
-					config.PIHolePassword = c.PIHolePassword[i]
-				}
-			}
+		if hasData, data, isValid := extractStringConfig(c.PIHoleApiToken, i, hostsCount); hasData {
+			config.PIHoleApiToken = data
+		} else if !isValid {
+			return nil, errors.New(fmt.Sprintf("Wrong number of PIHoleApiToken %d (Hosts: %d). PIHoleApiToken can be empty to use default, one value to use for all hosts, or match the number of hosts", len(c.PIHoleApiToken), hostsCount))
+		}
+
+		if hasData, data, isValid := extractStringConfig(c.PIHolePassword, i, hostsCount); hasData {
+			config.PIHolePassword = data
+		} else if !isValid {
+			return nil, errors.New("Wrong number of PIHolePassword. PIHolePassword can be empty to use default, one value to use for all hosts, or match the number of hosts")
 		}
 
 		result = append(result, config)
 	}
-	return result
+
+	return result, nil
+}
+
+func extractStringConfig(data []string, idx int, hostsCount int) (bool, string, bool) {
+	if len(data) == 1 {
+		v := strings.TrimSpace(data[0])
+		if v != "" {
+			return true, v, true
+		}
+	} else if len(data) == hostsCount {
+		v := strings.TrimSpace(data[idx])
+		if v != "" {
+			return true, v, true
+		}
+	} else if len(data) != 0 { //Host count missmatch
+		return false, "", false
+	}
+
+	// Empty
+	return false, "", true
 }
 
 func (c Config) hostnameURL() string {

config/configuration_test.go

@@ -0,0 +1,154 @@
+package config
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+const (
+	PIHOLE_HOSTNAME  = "PIHOLE_HOSTNAME"
+	PIHOLE_PORT      = "PIHOLE_PORT"
+	PIHOLE_API_TOKEN = "PIHOLE_API_TOKEN"
+	PIHOLE_PROTOCOL  = "PIHOLE_PROTOCOL"
+)
+
+type EnvInitiazlier func(*testing.T)
+
+type TestCase struct {
+	Name        string
+	Initializer EnvInitiazlier
+}
+
+func TestSplitDefault(t *testing.T) {
+	assert := assert.New(t)
+
+	env := getDefaultEnvConfig()
+
+	clientConfigs, err := env.Split()
+	assert.NoError(err)
+
+	clientConfig := clientConfigs[0]
+	assert.Equal("127.0.0.1", clientConfig.PIHoleHostname)
+	assert.Equal("http", clientConfig.PIHoleProtocol)
+	assert.Equal(uint16(80), clientConfig.PIHolePort)
+	assert.Empty(clientConfig.PIHoleApiToken)
+	assert.Empty(clientConfig.PIHolePassword)
+}
+
+func TestSplitMultipleHostWithSameConfig(t *testing.T) {
+	assert := assert.New(t)
+
+	env := getDefaultEnvConfig()
+	env.PIHoleHostname = []string{"127.0.0.1", "127.0.0.2", "127.0.0.3"}
+	env.PIHoleApiToken = []string{"api-token"}
+	env.PIHolePort = []uint16{8080}
+
+	clientConfigs, err := env.Split()
+	assert.NoError(err)
+	assert.Len(clientConfigs, 3)
+
+	testCases := []struct {
+		Host     string
+		Port     uint16
+		Protocol string
+	}{
+		{
+			Host:     "127.0.0.1",
+			Port:     8080,
+			Protocol: "http",
+		},
+		{
+			Host:     "127.0.0.2",
+			Port:     8080,
+			Protocol: "http",
+		},
+		{
+			Host:     "127.0.0.3",
+			Port:     8080,
+			Protocol: "http",
+		},
+	}
+
+	for i, tc := range testCases {
+		t.Run(fmt.Sprintf("Test %s", tc.Host), func(t *testing.T) {
+			clientConfig := clientConfigs[i]
+
+			assert.Equal(tc.Host, clientConfig.PIHoleHostname)
+			assert.Equal(tc.Protocol, clientConfig.PIHoleProtocol)
+			assert.Equal(tc.Port, clientConfig.PIHolePort)
+			assert.Equal("api-token", clientConfig.PIHoleApiToken)
+			assert.Empty(clientConfig.PIHolePassword)
+		})
+	}
+}
+
+func TestSplitMultipleHostWithMultipleConfigs(t *testing.T) {
+	assert := assert.New(t)
+
+	env := getDefaultEnvConfig()
+	env.PIHoleHostname = []string{"127.0.0.1", "127.0.0.2", "127.0.0.3"}
+	env.PIHoleApiToken = []string{"api-token1", "", "api-token3"}
+	env.PIHolePassword = []string{"", "password2", ""}
+	env.PIHolePort = []uint16{8081, 8082, 8083}
+
+	clientConfigs, err := env.Split()
+	assert.NoError(err)
+	assert.Len(clientConfigs, 3)
+
+	testCases := []struct {
+		Host     string
+		Port     uint16
+		Protocol string
+		ApiToken string
+		Password string
+	}{
+		{
+			Host:     "127.0.0.1",
+			Port:     8081,
+			Protocol: "http",
+			ApiToken: "api-token1",
+			Password: "",
+		},
+		{
+			Host:     "127.0.0.2",
+			Port:     8082,
+			Protocol: "http",
+			ApiToken: "",
+			Password: "password2",
+		},
+		{
+			Host:     "127.0.0.3",
+			Port:     8083,
+			Protocol: "http",
+			ApiToken: "api-token3",
+			Password: "",
+		},
+	}
+
+	for i, tc := range testCases {
+		t.Run(fmt.Sprintf("Test %s", tc.Host), func(t *testing.T) {
+			clientConfig := clientConfigs[i]
+
+			assert.Equal(tc.Host, clientConfig.PIHoleHostname)
+			assert.Equal(tc.Protocol, clientConfig.PIHoleProtocol)
+			assert.Equal(tc.Port, clientConfig.PIHolePort)
+			assert.Equal(tc.ApiToken, clientConfig.PIHoleApiToken)
+			assert.Equal(tc.Password, clientConfig.PIHolePassword)
+		})
+	}
+}
+
+func TestWrongParams(t *testing.T) {
+	assert := assert.New(t)
+
+	env := getDefaultEnvConfig()
+	env.PIHoleHostname = []string{"127.0.0.1", "127.0.0.2", "127.0.0.3"}
+	env.PIHoleApiToken = []string{"api-token1", "api-token2"}
+	env.PIHolePort = []uint16{808}
+
+	clientConfigs, err := env.Split()
+	assert.Errorf(err, "Wrong number of PIHoleApiToken. PIHoleApiToken can be empty to use default, one value to use for all hosts, or match the number of hosts")
+	assert.Nil(clientConfigs)
+}

go.mod

@@ -5,6 +5,7 @@ go 1.15
 require (
 	github.com/heetch/confita v0.10.0
 	github.com/prometheus/client_golang v1.11.0
+	github.com/stretchr/testify v1.7.0
 	github.com/xonvanetta/shutdown v0.0.3
 	golang.org/x/net v0.0.0-20200625001655-4c5254603344
 )

go.sum

@@ -123,6 +123,8 @@ github.com/konsorten/go-windows-terminal-sequences v1.0.3/go.mod h1:T0+1ngSBFLxv
 github.com/kr/logfmt v0.0.0-20140226030751-b84e30acd515/go.mod h1:+0opPa2QZZtGFBFZlji/RkVcI2GknAs/DXo4wKdlNEc=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
+github.com/kr/pretty v0.2.1 h1:Fmg33tUaq4/8ym9TJN1x7sLJnHVwhP33CNkpYV/7rwI=
+github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
@@ -195,12 +197,15 @@ github.com/sirupsen/logrus v1.4.2/go.mod h1:tLMulIdttU9McNUspp0xgXVQah82FyeX6Mwd
 github.com/sirupsen/logrus v1.6.0/go.mod h1:7uNnSEd1DgxDLC74fIahvMZmmYsHGZGEOFrfsX/uA88=
 github.com/soheilhy/cmux v0.1.4/go.mod h1:IM3LyeVVIOuxMH7sFAkER9+bJ4dT7Ms6E4xg4kGIyLM=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.1.1 h1:2vfRuCMp5sSVIDSqO8oNnWJq7mPa6KVP3iPIwFBuy8A=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.6.0 h1:jlIyCplCJFULU/01vCkhKuTyc3OorI3bJFuw6obfgho=
 github.com/stretchr/testify v1.6.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
+github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/tmc/grpc-websocket-proxy v0.0.0-20190109142713-0ad062ec5ee5/go.mod h1:ncp9v5uamzpCO7NfCPTXjqaC+bZgJeR0sMTm6dMHP7U=
 github.com/tv42/httpunix v0.0.0-20150427012821-b75d8614f926/go.mod h1:9ESjWnEqriFuLhtthL60Sar/7RFoluCcXsuvEwTV5KM=
 github.com/ugorji/go v1.1.4/go.mod h1:uQMGLiO92mf5W77hV/PUCpI3pbzQx3CRekS0kk+RGrc=
@@ -292,6 +297,8 @@ gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
+gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
 gopkg.in/resty.v1 v1.12.0/go.mod h1:mDo4pnntr5jdWRML875a/NmxYqAlA73dVijT2AXvQQo=
 gopkg.in/square/go-jose.v2 v2.3.1/go.mod h1:M9dMgbHiYLoDGQrXy7OpJDJWiKiU//h+vD76mk0e1AI=
 gopkg.in/yaml.v2 v2.0.0-20170812160011-eb3733d160e7/go.mod h1:JAlM8MvJe8wmxCU4Bli9HhUf9+ttbYbLASfIpnQbh74=

main.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"fmt"
+	"log"
 
 	"github.com/eko/pihole-exporter/config"
 	"github.com/eko/pihole-exporter/internal/metrics"
@@ -11,7 +12,10 @@ import (
 )
 
 func main() {
-	envConf, clientConfigs := config.Load()
+	envConf, clientConfigs, err := config.Load()
+	if err != nil {
+		log.Fatal(err.Error())
+	}
 
 	metrics.Init()