Add CLI parsing

go.mod

@@ -3,6 +3,8 @@ module github.com/chubin/wttr.in
 go 1.16
 
 require (
+	github.com/alecthomas/kong v0.7.1 // indirect
 	github.com/hashicorp/golang-lru v0.6.0
 	github.com/robfig/cron v1.2.0
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -1,4 +1,9 @@
+github.com/alecthomas/assert/v2 v2.1.0/go.mod h1:b/+1DI2Q6NckYi+3mXyH3wFb8qG37K/DuK80n7WefXA=
+github.com/alecthomas/kong v0.7.1 h1:azoTh0IOfwlAX3qN9sHWTxACE2oV8Bg2gAwBsMwDQY4=
+github.com/alecthomas/kong v0.7.1/go.mod h1:n1iCIO2xS46oE8ZfYCNDqdR0b0wZNrXAIAqro/2132U=
+github.com/alecthomas/repr v0.1.0/go.mod h1:2kn6fqh/zIyPLmm3ugklbEi5hg5wS435eygvNfaDQL8=
 github.com/hashicorp/golang-lru v0.6.0 h1:uL2shRDx7RTrOrTCUZEGP/wJUFiUI8QT6E7z5o8jga4=
 github.com/hashicorp/golang-lru v0.6.0/go.mod h1:iADmTwqILo4mZ8BN3D2Q6+9jd8WM5uGBxy+E8yxSoD4=
+github.com/hexops/gotextdiff v1.0.3/go.mod h1:pSWU5MAI3yDq+fZBTazCSJysOMbxWL1BSow5/V2vxeg=
 github.com/robfig/cron v1.2.0 h1:ZjScXvvxeQ63Dbyxy76Fj3AT3Ut0aKsyd2/tl3DTMuQ=
 github.com/robfig/cron v1.2.0/go.mod h1:JGuDeoQd7Z6yL4zQhZ3OPEVHB7fL6Ka6skscFHfmt2k=

srv.go

@@ -2,17 +2,26 @@ package main
 
 import (
 	"crypto/tls"
+	"errors"
 	"fmt"
 	"io"
 	"log"
 	"net/http"
 	"time"
 
+	"github.com/alecthomas/kong"
+
 	"github.com/chubin/wttr.in/internal/config"
 	"github.com/chubin/wttr.in/internal/logging"
 	"github.com/chubin/wttr.in/internal/processor"
 )
 
+var cli struct {
+	ConfigCheck bool   `name:"config-check" help:"Check configuration"`
+	ConfigDump  bool   `name:"config-dump" help:"Dump configuration"`
+	ConfigFile  string `name:"config-file" arg:"" optional:"" help:"Name of configuration file"`
+}
+
 const logLineStart = "LOG_LINE_START "
 
 func copyHeader(dst, src http.Header) {