feat: gettin there

TODO.md

@@ -0,0 +1,31 @@
+# doggo - v1.0 Milestone
+
+## Resolver
+- [ ] Create a DNS Resolver struct
+- [ ] Add methods to initialise the config, set defaults
+- [ ] Add a resolve method
+- [ ] Make it separate from Hub
+
+## CLI Features
+- [ ] `digfile`
+- [ ] `ndots` support
+- [ ] `search path` support
+- [ ] JSON output
+- [ ] Colorized output
+- [ ] Table output
+
+## CLI Grunt
+- [ ] Query args
+- [ ] Neatly package them to load args in different functions
+- [ ] Upper case is not mandatory for query type/classes
+
+## Tests
+
+## Documentation
+
+## Release Checklist
+- [ ] Add packages to all package managers
+- [ ] Snap
+- [ ] Homebrew
+- [ ] Alpine Linux
+- [ ] ARM support too

cmd/cli.go

@@ -4,9 +4,9 @@ import (
 	"os"
 	"strings"
 
-	"github.com/mr-karan/doggo/pkg/resolver"
+	resolver "github.com/mr-karan/doggo/pkg/resolve"
 	"github.com/sirupsen/logrus"
-	"github.com/urfave/cli"
+	"github.com/urfave/cli/v2"
 )
 
 var (
@@ -37,23 +37,28 @@ func main() {
 	app.Name = "doggo"
 	app.Usage = "Command-line DNS Client"
 	app.Version = buildVersion
-	app.Author = "Karan Sharma @mrkaran"
-	// Register command line args.
-	app.Flags = []cli.Flag{
-		cli.BoolFlag{
-			Name:  "verbose",
-			Usage: "Enable verbose logging",
-		},
-	}
 	var (
 		logger = initLogger(true)
 	)
 	// Initialize hub.
 	hub := NewHub(logger, buildVersion)
-
+	// Register command line args.
+	app.Flags = []cli.Flag{
+		&cli.StringSliceFlag{
+			Name:        "query",
+			Usage:       "Domain name to query",
+			Destination: hub.Domains,
+		},
+		&cli.BoolFlag{
+			Name:  "verbose",
+			Usage: "Enable verbose logging",
+		},
+	}
 	app.Action = func(c *cli.Context) error {
+
 		// parse arguments
-		for _, arg := range c.Args() {
+		var domains cli.StringSlice
+		for _, arg := range c.Args().Slice() {
 			if strings.HasPrefix(arg, "@") {
 				hub.Nameservers = append(hub.Nameservers, arg)
 			} else if isUpper(arg) {
@@ -63,7 +68,8 @@ func main() {
 					hub.QClass = append(hub.QClass, arg)
 				}
 			} else {
-				hub.Domains = append(hub.Domains, arg)
+				domains.Set(arg)
+				hub.Domains = &domains
 			}
 		}
 		// load defaults

cmd/hub.go

@@ -2,14 +2,14 @@ package main
 
 import (
 	"github.com/sirupsen/logrus"
-	"github.com/urfave/cli"
+	"github.com/urfave/cli/v2"
 )
 
 // Hub represents the structure for all app wide functions and structs.
 type Hub struct {
 	Logger      *logrus.Logger
 	Version     string
-	Domains     []string
+	Domains     *cli.StringSlice
 	QTypes      []string
 	QClass      []string
 	Nameservers []string

cmd/parse.go

@@ -0,0 +1,13 @@
+package main
+
+func (hub *Hub) loadFlags() {
+
+}
+
+func (hub *Hub) loadFreeForm() {
+
+}
+
+func (hub *Hub) loadFallbacks() {
+
+}

cmd/resolve.go

@@ -8,12 +8,12 @@ import (
 
 // Resolve resolves the domain name
 func (hub *Hub) Resolve() {
-	var messages = make([]dns.Msg, 0, len(hub.Domains))
+	var messages = make([]dns.Msg, 0, len(hub.Domains.Value()))
-	for _, d := range hub.Domains {
+	for _, d := range hub.Domains.Value() {
 		msg := dns.Msg{}
 		msg.Id = dns.Id()
 		msg.RecursionDesired = true
-		msg.Question = []dns.Question{(dns.Question{d, dns.TypeA, dns.ClassINET})}
+		msg.Question = []dns.Question{(dns.Question{dns.Fqdn(d), dns.TypeA, dns.ClassINET})}
 		messages = append(messages, msg)
 	}
 	c := new(dns.Client)
@@ -27,6 +27,6 @@ func (hub *Hub) Resolve() {
 				fmt.Println(t.String())
 			}
 		}
-		fmt.Println("rtt is", rtt, msg.Question)
+		fmt.Println("rtt is", rtt, msg.Question[0].Name)
 	}
 }

go.mod

@@ -5,5 +5,5 @@ go 1.15
 require (
 	github.com/miekg/dns v1.1.35
 	github.com/sirupsen/logrus v1.7.0
-	github.com/urfave/cli v1.22.5
+	github.com/urfave/cli/v2 v2.3.0
 )

go.sum

@@ -1,9 +1,11 @@
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/cpuguy83/go-md2man/v2 v2.0.0-20190314233015-f79a8a8ca69d h1:U+s90UTSYgptZMwQh2aRr3LuazLJIa+Pg3Kc1ylSYVY=
 github.com/cpuguy83/go-md2man/v2 v2.0.0-20190314233015-f79a8a8ca69d/go.mod h1:maD7wRr/U5Z6m/iR4s+kqSMx2CaBsrgA7czyZG/E6dU=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/miekg/dns v1.1.35 h1:oTfOaDH+mZkdcgdIjH6yBajRGtIwcwcaR+rt23ZSrJs=
 github.com/miekg/dns v1.1.35/go.mod h1:KNUDUusw/aVsxyTYZM1oqvCicbwhgbNgztCETuNZ7xM=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/russross/blackfriday/v2 v2.0.1 h1:lPqVAte+HuHNfhJ/0LC98ESWRz8afy9tM/0RK8m9o+Q=
 github.com/russross/blackfriday/v2 v2.0.1/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
@@ -11,9 +13,10 @@ github.com/shurcooL/sanitized_anchor_name v1.0.0 h1:PdmoCO6wvbs+7yrJyMORt4/BmY5I
 github.com/shurcooL/sanitized_anchor_name v1.0.0/go.mod h1:1NzhyTcUVG4SuEtjjoZeVRXNmyL/1OwPU0+IJeTBvfc=
 github.com/sirupsen/logrus v1.7.0 h1:ShrD1U9pZB12TX0cVy0DtePoCH97K8EtX+mg7ZARUtM=
 github.com/sirupsen/logrus v1.7.0/go.mod h1:yWOB1SBYBC5VeMP7gHvWumXLIWorT60ONWic61uBYv0=
+github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
-github.com/urfave/cli v1.22.5 h1:lNq9sAHXK2qfdI8W+GRItjCEkI+2oR4d+MEHy1CKXoU=
+github.com/urfave/cli/v2 v2.3.0 h1:qph92Y649prgesehzOrQjdWyxFOp/QVM+6imKHad91M=
-github.com/urfave/cli v1.22.5/go.mod h1:Gos4lmkARVdJ6EkW0WaNv/tZAAMe9V7XWyB60NtXRu0=
+github.com/urfave/cli/v2 v2.3.0/go.mod h1:LJmUH05zAU44vOAcrfzZQKsZbVcdbOG8rtL3/XcUArI=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550 h1:ObdrDkeb4kJdCP557AjRjq69pTHfNouLtWZG7j9rPN8=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
@@ -22,6 +25,7 @@ golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20190923162816-aa69164e4478 h1:l5EDrHhldLYb3ZRHDUhXF7Om7MvYXnkV9/iQNo1lX6g=
 golang.org/x/net v0.0.0-20190923162816-aa69164e4478/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/sync v0.0.0-20190423024810-112230192c58 h1:8gQV6CLnAEikrhgkHFbMAEhagSSnXWGV915qUMm9mrU=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/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=
@@ -33,4 +37,4 @@ golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/tools v0.0.0-20191216052735-49a3e744a425/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
-gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.2.3/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

pkg/models/models.go

@@ -0,0 +1,12 @@
+package models
+
+// Question represents a given query to the client.
+// A question can have multiple domains, multiple nameservers
+// but it's the responsibility of the client to send each question
+// to the nameserver and collect responses.
+type Question struct {
+	Domain      []string
+	Nameservers []string
+	QClass      []uint16
+	QType       []uint16
+}

pkg/resolve/nameserver.go

@@ -1,4 +1,4 @@
-package resolver
+package resolve
 
 import (
 	"bufio"

pkg/resolve/resolver.go

@@ -0,0 +1,91 @@
+package resolve
+
+import (
+	"fmt"
+	"net"
+
+	"github.com/miekg/dns"
+)
+
+// Resolver holds the configuration for a dns.Client
+type Resolver struct {
+	client  *dns.Client
+	servers []string
+}
+
+//DefaultResolvConfPath specifies path to default resolv config file on UNIX.
+const DefaultResolvConfPath = "/etc/resolv.conf"
+
+// NewResolver accepts a list of nameservers and configures a DNS resolver.
+func NewResolver(servers []string) *Resolver {
+	client := &dns.Client{}
+	return &Resolver{
+		client:  client,
+		servers: servers,
+	}
+}
+
+// NewResolverFromResolvFile loads the configuration from resolv config file
+// and initialises a DNS resolver.
+func NewResolverFromResolvFile(resolvFilePath string) (*Resolver, error) {
+	if resolvFilePath == "" {
+		resolvFilePath = DefaultResolvConfPath
+	}
+	cfg, err := dns.ClientConfigFromFile(resolvFilePath)
+	if err != nil {
+		return nil, err
+	}
+
+	servers := make([]string, 0, len(cfg.Servers))
+	for _, s := range cfg.Servers {
+		ip := net.ParseIP(s)
+		// handle IPv6
+		if ip != nil && ip.To4() != nil {
+			servers = append(servers, fmt.Sprintf("%s:%s", s, cfg.Port))
+		} else {
+			servers = append(servers, fmt.Sprintf("[%s]:%s", s, cfg.Port))
+		}
+	}
+
+	client := &dns.Client{}
+	return &Resolver{
+		client:  client,
+		servers: servers,
+	}, nil
+}
+
+func (r *Resolver) Lookup(domains []string) []error {
+	// Prepare a list of DNS messages to be sent to the server.
+	// It's possible to send multiple question in one message
+	// but some nameservers are not able to
+	var messages = make([]dns.Msg, 0, len(domains))
+
+	for _, d := range domains {
+		msg := dns.Msg{}
+		msg.Id = dns.Id()
+		msg.RecursionDesired = true
+		// It's recommended to only send 1 question for 1 DNS message.
+		msg.Question = []dns.Question{(dns.Question{
+			Name:   dns.Fqdn(d),
+			Qtype:  dns.TypeA,
+			Qclass: dns.ClassINET,
+		})}
+		messages = append(messages, msg)
+	}
+	var errors []error
+	for _, msg := range messages {
+		for _, srv := range r.servers {
+			in, rtt, err := r.client.Exchange(&msg, srv)
+			if err != nil {
+				errors = append(errors, err)
+			}
+			for _, ans := range in.Answer {
+				if t, ok := ans.(*dns.A); ok {
+					fmt.Println(t.String())
+				}
+			}
+			fmt.Println("rtt is", rtt, msg.Question)
+		}
+	}
+	return errors
+}