policy: Impl Addressing{} and Recipient{} for #84

pkg/policy/address.go

@@ -3,9 +3,48 @@ package policy
 import (
 	"bytes"
 	"fmt"
+	"net/mail"
 	"strings"
+
+	"github.com/jhillyerd/inbucket/pkg/config"
 )
 
+// Addressing handles email address policy.
+type Addressing struct {
+	Config config.SMTPConfig
+}
+
+// NewRecipient parses an address into a Recipient.
+func (a *Addressing) NewRecipient(address string) (*Recipient, error) {
+	local, domain, err := ParseEmailAddress(address)
+	if err != nil {
+		return nil, err
+	}
+	mailbox, err := ParseMailboxName(local)
+	if err != nil {
+		return nil, err
+	}
+	ar, err := mail.ParseAddress(address)
+	if err != nil {
+		return nil, err
+	}
+	return &Recipient{
+		Address:   *ar,
+		apolicy:   a,
+		LocalPart: local,
+		Domain:    domain,
+		Mailbox:   mailbox,
+	}, nil
+}
+
+// ShouldStoreDomain indicates if Inbucket stores email destined for the specified domain.
+func (a *Addressing) ShouldStoreDomain(domain string) bool {
+	if a.Config.StoreMessages {
+		return strings.ToLower(domain) != strings.ToLower(a.Config.DomainNoStore)
+	}
+	return false
+}
+
 // ParseMailboxName takes a localPart string (ex: "user+ext" without "@domain")
 // and returns just the mailbox name (ex: "user").  Returns an error if
 // localPart contains invalid characters; it won't accept any that must be
@@ -35,54 +74,6 @@ func ParseMailboxName(localPart string) (result string, err error) {
 	return result, nil
 }
 
-// ValidateDomainPart returns true if the domain part complies to RFC3696, RFC1035
-func ValidateDomainPart(domain string) bool {
-	if len(domain) == 0 {
-		return false
-	}
-	if len(domain) > 255 {
-		return false
-	}
-	if domain[len(domain)-1] != '.' {
-		domain += "."
-	}
-	prev := '.'
-	labelLen := 0
-	hasAlphaNum := false
-	for _, c := range domain {
-		switch {
-		case ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') ||
-			('0' <= c && c <= '9') || c == '_':
-			// Must contain some of these to be a valid label.
-			hasAlphaNum = true
-			labelLen++
-		case c == '-':
-			if prev == '.' {
-				// Cannot lead with hyphen.
-				return false
-			}
-		case c == '.':
-			if prev == '.' || prev == '-' {
-				// Cannot end with hyphen or double-dot.
-				return false
-			}
-			if labelLen > 63 {
-				return false
-			}
-			if !hasAlphaNum {
-				return false
-			}
-			labelLen = 0
-			hasAlphaNum = false
-		default:
-			// Unknown character.
-			return false
-		}
-		prev = c
-	}
-	return true
-}
-
 // ParseEmailAddress unescapes an email address, and splits the local part from the domain part.
 // An error is returned if the local or domain parts fail validation following the guidelines
 // in RFC3696.
@@ -202,3 +193,52 @@ LOOP:
 	}
 	return buf.String(), domain, nil
 }
+
+// ValidateDomainPart returns true if the domain part complies to RFC3696, RFC1035. Used by
+// ParseEmailAddress().
+func ValidateDomainPart(domain string) bool {
+	if len(domain) == 0 {
+		return false
+	}
+	if len(domain) > 255 {
+		return false
+	}
+	if domain[len(domain)-1] != '.' {
+		domain += "."
+	}
+	prev := '.'
+	labelLen := 0
+	hasAlphaNum := false
+	for _, c := range domain {
+		switch {
+		case ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') ||
+			('0' <= c && c <= '9') || c == '_':
+			// Must contain some of these to be a valid label.
+			hasAlphaNum = true
+			labelLen++
+		case c == '-':
+			if prev == '.' {
+				// Cannot lead with hyphen.
+				return false
+			}
+		case c == '.':
+			if prev == '.' || prev == '-' {
+				// Cannot end with hyphen or double-dot.
+				return false
+			}
+			if labelLen > 63 {
+				return false
+			}
+			if !hasAlphaNum {
+				return false
+			}
+			labelLen = 0
+			hasAlphaNum = false
+		default:
+			// Unknown character.
+			return false
+		}
+		prev = c
+	}
+	return true
+}

pkg/policy/address_test.go

@@ -4,9 +4,62 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/jhillyerd/inbucket/pkg/config"
 	"github.com/jhillyerd/inbucket/pkg/policy"
 )
 
+func TestShouldStoreDomain(t *testing.T) {
+	// Test with storage enabled.
+	ap := &policy.Addressing{
+		Config: config.SMTPConfig{
+			DomainNoStore: "Foo.Com",
+			StoreMessages: true,
+		},
+	}
+	testCases := []struct {
+		domain string
+		want   bool
+	}{
+		{domain: "bar.com", want: true},
+		{domain: "foo.com", want: false},
+		{domain: "FOO.com", want: false},
+		{domain: "bar.foo.com", want: true},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.domain, func(t *testing.T) {
+			got := ap.ShouldStoreDomain(tc.domain)
+			if got != tc.want {
+				t.Errorf("Got %v for %q, want: %v", got, tc.domain, tc.want)
+			}
+
+		})
+	}
+	// Test with storage disabled.
+	ap = &policy.Addressing{
+		Config: config.SMTPConfig{
+			StoreMessages: false,
+		},
+	}
+	testCases = []struct {
+		domain string
+		want   bool
+	}{
+		{domain: "bar.com", want: false},
+		{domain: "foo.com", want: false},
+		{domain: "FOO.com", want: false},
+		{domain: "bar.foo.com", want: false},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.domain, func(t *testing.T) {
+			got := ap.ShouldStoreDomain(tc.domain)
+			if got != tc.want {
+				t.Errorf("Got %v for %q, want: %v", got, tc.domain, tc.want)
+			}
+
+		})
+	}
+}
+
 func TestParseMailboxName(t *testing.T) {
 	var validTable = []struct {
 		input  string

pkg/policy/recipient.go

@@ -0,0 +1,25 @@
+package policy
+
+import "net/mail"
+
+// Recipient represents a potential email recipient, allows policies for it to be queried.
+type Recipient struct {
+	mail.Address
+	apolicy *Addressing
+	// LocalPart is the part of the address before @, including +extension.
+	LocalPart string
+	// Domain is the part of the address after @.
+	Domain string
+	// Mailbox is the canonical mailbox name for this recipient.
+	Mailbox string
+}
+
+// ShouldAccept returns true if Inbucket should accept mail for this recipient.
+func (r *Recipient) ShouldAccept() bool {
+	return true
+}
+
+// ShouldStore returns true if Inbucket should store mail for this recipient.
+func (r *Recipient) ShouldStore() bool {
+	return r.apolicy.ShouldStoreDomain(r.Domain)
+}