added window information to the README.md

.github/workflows/go.yml

@@ -19,7 +19,13 @@ jobs:
 
     - name: Test
       run: go test -v ./...
-      
+
+    - name: Lint source code
+      run: |
+        make tools lint
+        rm -rf .bin/
+        rm -rf dist/
+
     - name: Create release tag
       run: |
         git tag "v$(git show -s --format=%cd --date=format:%Y%m%d.%H%M%S)"

.golangci.yaml

@@ -0,0 +1,26 @@
+linters:
+  disable-all: true
+  enable:
+    - deadcode
+    - errcheck
+    - gofmt
+    - goimports
+    - gosimple
+    - ineffassign
+    - misspell
+    - staticcheck
+    - structcheck
+    - unconvert
+    - unused
+    - varcheck
+    - govet
+
+linters-settings:
+  goimports:
+    local-prefixes: github.com/bastiandoetsch/mullvad-best-server
+
+output:
+  format: tab
+
+run:
+  deadline: 10m

.goreleaser.yaml

@@ -1,20 +1,20 @@
 project_name: mullvad-best-server
-# This is an example .goreleaser.yml file with some sensible defaults.
-# Make sure to check the documentation at https://goreleaser.com
+
 before:
   hooks:
-    # You may remove this if you don't use go modules.
     - go mod tidy
-    # you may remove this if you don't need go generate
-    - go generate ./...
+
 builds:
-  - env:
+  - flags:
+    - -trimpath
+    env:
       - CGO_ENABLED=0
     goos:
       - linux
       - windows
       - darwin
     mod_timestamp: "{{ .CommitTimestamp }}"
+
 archives:
   - replacements:
       darwin: Darwin
@@ -24,13 +24,16 @@ archives:
       amd64: x86_64
     format: binary
     name_template: "{{ .ProjectName }}_{{ .Version }}_{{ .Os }}_{{ .Arch }}"
+
 checksum:
   name_template: 'checksums.txt'
+
 snapshot:
   name_template: "{{ incpatch .Version }}-next"
+
 changelog:
   sort: asc
   filters:
     exclude:
       - '^docs:'
-      - '^test:'
+      - '^test:'

Makefile

@@ -0,0 +1,60 @@
+# project variables
+PROJECT_NAME := mullvad-best-server
+
+# build variables
+.DEFAULT_GOAL = lint
+BUILD_DIR := dist
+DEV_GOARCH := $(shell go env GOARCH)
+DEV_GOOS := $(shell go env GOOS)
+
+
+## tools: Install required tooling.
+.PHONY: tools
+tools:
+ifeq (,$(wildcard ./.bin/golangci-lint*))
+	@curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b .bin/ v1.44.2
+else
+	@echo "==> Required tooling is already installed"
+endif
+
+## clean: Delete the build directory
+.PHONY: clean
+clean:
+	@echo "==> Removing '$(BUILD_DIR)' directory..."
+	@rm -rf $(BUILD_DIR)
+
+## lint: Lint code with golangci-lint.
+.PHONY: lint
+lint: tools
+	@echo "==> Linting code with 'golangci-lint'..."
+	@.bin/golangci-lint run ./...
+
+## test: Run all unit tests.
+.PHONY: test
+test:
+	@echo "==> Running unit tests..."
+	@mkdir -p $(BUILD_DIR)
+	@go test -count=1 -v -cover -coverprofile=$(BUILD_DIR)/coverage.out -parallel=4 ./...
+
+## build: Build binary for default local system's OS and architecture.
+.PHONY: build
+build:
+	@echo "==> Building binary..."
+	@echo "    running go build for GOOS=$(DEV_GOOS) GOARCH=$(DEV_GOARCH)"
+# workaround for missing .exe extension on Windows
+ifeq ($(OS),Windows_NT)
+	@go build -o $(BUILD_DIR)/$(PROJECT_NAME).$(DEV_GOOS).$(DEV_GOARCH).exe
+else
+	@go build -o $(BUILD_DIR)/$(PROJECT_NAME).$(DEV_GOOS).$(DEV_GOARCH)
+endif
+
+.PHONY: run
+run:
+	@echo "==> Running $(PROJECT_NAME)"
+	@go run main.go
+
+help: Makefile
+	@echo "Usage: make <command>"
+	@echo ""
+	@echo "Commands:"
+	@sed -n 's/^##//p' $< | column -t -s ':' | sed -e 's/^/ /'

README.md

@@ -1,7 +1,12 @@
 # mullvad-best-server
 ![Build](https://github.com/bastiandoetsch/mullvad-best-server/actions/workflows/go.yml/badge.svg)
 
-Determines the mullvad.net server with the lowest latency. 
+Determines the mullvad.net server with the lowest latency on macOS and Linux. On Windows, it can only check if the server is up.
+The reason lies with the golang network libraries, according to the `go-ping` library, that is used under the hood for pinging: 
+
+```
+Please note that accessing packet TTL values is not supported due to limitations in the Go x/net/ipv4 and x/net/ipv6 packages.
+```
 
 ## Installation
 
@@ -17,6 +22,8 @@ Execute `mullvad-best-server`. It outputs the code, e.g. `de05`. You can then co
 Usage of dist/mullvad-best-server_darwin_amd64/mullvad-best-server:
 -c string
   Server country code, e.g. ch for Switzerland (default "ch")
+-l string
+  Log level. Allowed values: trace, debug, info, warn, error, fatal, panic (default "info")
 -o string
   Output format. 'json' outputs server json
 -t string
@@ -28,5 +35,17 @@ The `-c` flag allows to give a country code. Else `ch` will be used.
 
 
 ## Background
-The program uses `https://api.mullvad.net/www/relays/<SERVER_TYPE/` to get the current server list, pings the ones with the right country
+The program uses `https://api.mullvad.net/www/relays/<SERVER_TYPE>/` to get the current server list, pings the ones with the right country
 and outputs the server with the lowest ping.
+
+## Integration into a script
+I use it on my router like this (yes, I know I could have done the whole thing with jq and shell scripting, but wanted to use go for maintainability).
+```
+#!/bin/sh
+set -e
+LATEST_RELEASE=$(curl -sSL https://api.github.com/repos/bastiandoetsch/mullvad-best-server/releases/latest | jq -r '.assets[]| .browser_download_url' | grep Linux_arm64)
+curl -sSL $LATEST_RELEASE > /root/mullvad-best-server
+chmod +x /root/mullvad-best-server
+/usr/bin/wg-quick down $(wg show|grep interface | cut -d: -f2)  || echo "nothing to shut down"
+/usr/bin/wg-quick up "mullvad-$(/root/mullvad-best-server -c de)"
+```

go.mod

@@ -3,13 +3,15 @@ module github.com/bastiandoetsch/mullvad-best-server
 go 1.17
 
 require (
-	github.com/go-ping/ping v0.0.0-20211130115550-779d1e919534
-	github.com/rs/zerolog v1.26.1
+	github.com/go-ping/ping v1.1.0
+	github.com/rs/zerolog v1.27.0
 )
 
 require (
-	github.com/google/uuid v1.2.0 // indirect
-	golang.org/x/net v0.0.0-20210805182204-aaa1db679c0d // indirect
-	golang.org/x/sync v0.0.0-20210220032951-036812b2e83c // indirect
-	golang.org/x/sys v0.0.0-20210809222454-d867a43fc93e // indirect
+	github.com/google/uuid v1.3.0 // indirect
+	github.com/mattn/go-colorable v0.1.12 // indirect
+	github.com/mattn/go-isatty v0.0.14 // indirect
+	golang.org/x/net v0.0.0-20220728211354-c7608f3a8462 // indirect
+	golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4 // indirect
+	golang.org/x/sys v0.0.0-20220728004956-3c1f35247d10 // indirect
 )

go.sum

@@ -1,41 +1,33 @@
-github.com/coreos/go-systemd/v22 v22.3.2/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
-github.com/go-ping/ping v0.0.0-20211130115550-779d1e919534 h1:dhy9OQKGBh4zVXbjwbxxHjRxMJtLXj3zfgpBYQaR4Q4=
-github.com/go-ping/ping v0.0.0-20211130115550-779d1e919534/go.mod h1:xIFjORFzTxqIV/tDVGO4eDy/bLuSyawEeojSm3GfRGk=
+github.com/coreos/go-systemd/v22 v22.3.3-0.20220203105225-a9a7ef127534/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
+github.com/go-ping/ping v1.1.0 h1:3MCGhVX4fyEUuhsfwPrsEdQw6xspHkv5zHsiSoDFZYw=
+github.com/go-ping/ping v1.1.0/go.mod h1:xIFjORFzTxqIV/tDVGO4eDy/bLuSyawEeojSm3GfRGk=
 github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
-github.com/google/uuid v1.2.0 h1:qJYtXnJRWmpe7m/3XlyhrsLrEURqHRM2kxzoxXqyUDs=
 github.com/google/uuid v1.2.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
+github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/mattn/go-colorable v0.1.12 h1:jF+Du6AlPIjs2BiUiQlKOX0rt3SujHxPnksPKZbaA40=
+github.com/mattn/go-colorable v0.1.12/go.mod h1:u5H1YNBxpqRaxsYJYSkiCWKzEfiAb1Gb520KVy5xxl4=
+github.com/mattn/go-isatty v0.0.14 h1:yVuAays6BHfxijgZPzw+3Zlu5yQgKGP2/hcQbHb7S9Y=
+github.com/mattn/go-isatty v0.0.14/go.mod h1:7GGIvUiUoEMVVmxf/4nioHXj79iQHKdU27kJ6hsGG94=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/rs/xid v1.3.0/go.mod h1:trrq9SKmegXys3aeAKXMUTdJsYXVwGY3RLcfgqegfbg=
-github.com/rs/zerolog v1.26.1 h1:/ihwxqH+4z8UxyI70wM1z9yCvkWcfz/a3mj48k/Zngc=
-github.com/rs/zerolog v1.26.1/go.mod h1:/wSSJWX7lVrsOwlbyTRSOJvqRlc+WjWlfes+CiJ+tmc=
-github.com/yuin/goldmark v1.4.0/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
-golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
-golang.org/x/crypto v0.0.0-20211215165025-cf75a172585e/go.mod h1:P+XmwS30IXTQdn5tA2iutPOUgjI07+tq3H3K9MVA1s8=
-golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
-golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
-golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
-golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
+github.com/rs/zerolog v1.27.0 h1:1T7qCieN22GVc8S4Q2yuexzBb1EqjbgjSH9RohbMjKs=
+github.com/rs/zerolog v1.27.0/go.mod h1:7frBqO0oezxmnO7GF86FY++uy8I0Tk/If5ni1G9Qc0U=
 golang.org/x/net v0.0.0-20210316092652-d523dce5a7f4/go.mod h1:RBQZq4jEuRlivfhVLdyRGr576XBO4/greRjx4P4O3yc=
-golang.org/x/net v0.0.0-20210805182204-aaa1db679c0d h1:20cMwl2fHAzkJMEA+8J4JgqBQcQGzbisXo31MIeenXI=
-golang.org/x/net v0.0.0-20210805182204-aaa1db679c0d/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
-golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.0.0-20210220032951-036812b2e83c h1:5KslGYwFpkhGh+Q16bwMP3cOontH8FOep7tGV86Y7SQ=
+golang.org/x/net v0.0.0-20220728211354-c7608f3a8462 h1:UreQrH7DbFXSi9ZFox6FNT3WBooWmdANpU+IfkT1T4I=
+golang.org/x/net v0.0.0-20220728211354-c7608f3a8462/go.mod h1:YDH+HFinaLZZlnHAfSS6ZXJJ9M9t4Dl22yv3iI2vPwk=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4 h1:uVc8UZUe6tr40fFVnUP5Oj+veunVezqYl9z7DYw9xzw=
+golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210315160823-c6e025ad8005/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210809222454-d867a43fc93e h1:WUoyKPm6nCo1BnNUvPGnFG3T5DUVem42yDJZZ4CNxMA=
-golang.org/x/sys v0.0.0-20210809222454-d867a43fc93e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20210630005230-0f9fa26af87c/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20210927094055-39ccf1dd6fa6/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220728004956-3c1f35247d10 h1:WIoqL4EROvwiPdUtaip4VcDdpZ4kha7wBWZrbVKCIZg=
+golang.org/x/sys v0.0.0-20220728004956-3c1f35247d10/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
-golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
-golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
-golang.org/x/tools v0.1.7/go.mod h1:LGqMHiF4EqQNHR1JncWGqT5BVaXmza+X+BDGol+dOxo=
-golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

main.go

@@ -4,27 +4,35 @@ import (
 	"encoding/json"
 	"flag"
 	"fmt"
-	"github.com/go-ping/ping"
-	"github.com/rs/zerolog"
-	"github.com/rs/zerolog/log"
 	"io"
 	"io/ioutil"
 	"net/http"
+	"runtime"
 	"strings"
 	"time"
+
+	"github.com/go-ping/ping"
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/log"
 )
 
-var pings = make(map[string]time.Duration)
-
 func main() {
-	zerolog.SetGlobalLevel(zerolog.InfoLevel)
 	var outputFlag = flag.String("o", "", "Output format. 'json' outputs server json")
 	var countryFlag = flag.String("c", "ch", "Server country code, e.g. ch for Switzerland")
 	var typeFlag = flag.String("t", "wireguard", "Server type, e.g. wireguard")
+	var logLevel = flag.String("l", "info", "Log level. Allowed values: trace, debug, info, warn, error, fatal, panic")
 	flag.Parse()
 
+	level, err := zerolog.ParseLevel(*logLevel)
+	if err != nil {
+		log.Fatal().Err(err).Msg("Unable to set log level")
+	}
+	zerolog.SetGlobalLevel(level)
 	servers := getServers(*typeFlag)
 	bestIndex := selectBestServerIndex(servers, *countryFlag)
+	if bestIndex == -1 {
+		log.Fatal().Str("country", *countryFlag).Msg("No servers for country found.")
+	}
 	best := servers[bestIndex]
 	log.Debug().Interface("server", best).Msg("Best latency server found.")
 	hostname := strings.TrimSuffix(best.Hostname, "-wireguard")
@@ -33,24 +41,25 @@ func main() {
 	} else {
 		serverJson, err := json.Marshal(best)
 		if err != nil {
-			log.Fatal().Err(err)
+			log.Fatal().Err(err).Msg("Couldn't marshal server information to Json")
 		}
 		fmt.Println(string(serverJson))
 	}
 }
 
 func selectBestServerIndex(servers []server, country string) int {
-	best := servers[0].Hostname
 	bestIndex := -1
+	var bestPing time.Duration
 	for i, server := range servers {
 		if server.Active && server.CountryCode == country {
 			duration, err := serverLatency(server)
 			if err == nil {
-				pings[server.Hostname] = duration
-				if bestIndex == -1 || pings[best] > pings[server.Hostname] {
-					best = server.Hostname
+				if bestIndex == -1 || bestPing > duration {
 					bestIndex = i
+					bestPing = duration
 				}
+			} else {
+				log.Err(err).Msg("Error determining the server latency via ping.")
 			}
 		}
 	}
@@ -60,7 +69,7 @@ func selectBestServerIndex(servers []server, country string) int {
 func getServers(serverType string) []server {
 	resp, err := http.Get("https://api.mullvad.net/www/relays/" + serverType + "/")
 	if err != nil {
-		log.Fatal().Err(err)
+		log.Fatal().Err(err).Msg("Couldn't retrieve servers")
 	}
 	responseBody, err := ioutil.ReadAll(resp.Body)
 	defer func(Body io.ReadCloser) {
@@ -69,16 +78,23 @@ func getServers(serverType string) []server {
 			log.Err(err)
 		}
 	}(resp.Body)
+	if err != nil {
+		log.Fatal().Err(err)
+	}
 	var servers []server
 	err = json.Unmarshal(responseBody, &servers)
 	if err != nil {
-		log.Fatal().Err(err)
+		log.Fatal().Err(err).Msg("couldn't unmarshall server json")
 	}
 	return servers
 }
 
+//goland:noinspection GoBoolExpressions
 func serverLatency(s server) (time.Duration, error) {
 	pinger, err := ping.NewPinger(s.Ipv4AddrIn)
+	if runtime.GOOS == "windows" {
+		pinger.SetPrivileged(true)
+	}
 	pinger.Count = 1
 	if err != nil {
 		return 0, err