Merge pull request #1232 from Zheaoli/manjusaka/fix-1149

Remove duplicate host record when update the DNS

Author: AkihiroSuda

cmd/nerdctl/compose_up_linux_test.go

@@ -437,3 +437,56 @@ services:
 	base.ComposeCmd("-f", comp.YAMLFullPath(), "down").AssertOK()
 
 }
+
+func TestComposeUpWithExternalNetwork(t *testing.T) {
+	containerName1 := testutil.Identifier(t) + "-1"
+	containerName2 := testutil.Identifier(t) + "-2"
+	networkName := testutil.Identifier(t) + "-network"
+	var dockerComposeYaml1 = fmt.Sprintf(`
+version: "3"
+services:
+  %s:
+    image: %s
+    container_name: %s
+    networks:
+      %s:
+        aliases:
+          - nginx-1
+networks:
+  %s:
+    external: true
+`, containerName1, testutil.NginxAlpineImage, containerName1, networkName, networkName)
+	var dockerComposeYaml2 = fmt.Sprintf(`
+version: "3"
+services:
+  %s:
+    image: %s
+    container_name: %s
+    networks:
+      %s:
+        aliases:
+          - nginx-2
+networks:
+  %s:
+    external: true
+`, containerName2, testutil.NginxAlpineImage, containerName2, networkName, networkName)
+	comp1 := testutil.NewComposeDir(t, dockerComposeYaml1)
+	defer comp1.CleanUp()
+	comp2 := testutil.NewComposeDir(t, dockerComposeYaml2)
+	defer comp2.CleanUp()
+	base := testutil.NewBase(t)
+	// Create the test network
+	base.Cmd("network", "create", networkName).AssertOK()
+	defer base.Cmd("network", "rm", networkName).Run()
+	// Run the first compose
+	base.ComposeCmd("-f", comp1.YAMLFullPath(), "up", "-d").AssertOK()
+	defer base.ComposeCmd("-f", comp1.YAMLFullPath(), "down", "-v").Run()
+	// Run the second compose
+	base.ComposeCmd("-f", comp2.YAMLFullPath(), "up", "-d").AssertOK()
+	defer base.ComposeCmd("-f", comp2.YAMLFullPath(), "down", "-v").Run()
+	// Down the second compose
+	base.ComposeCmd("-f", comp2.YAMLFullPath(), "down", "-v").AssertOK()
+	// Run the second compose again
+	base.ComposeCmd("-f", comp2.YAMLFullPath(), "up", "-d").AssertOK()
+	base.Cmd("exec", containerName1, "wget", "-qO-", "http://"+containerName2).AssertOutContains(testutil.NginxAlpineIndexHTMLSnippet)
+}

pkg/dnsutil/hostsstore/updater.go

@@ -132,7 +132,7 @@ func (u *updater) phase2() error {
 		var buf bytes.Buffer
 		buf.WriteString(fmt.Sprintf("# %s\n", markerBegin))
 		buf.WriteString("127.0.0.1	localhost localhost.localdomain\n")
-		buf.WriteString(":1		localhost localhost.localdomain\n")
+		buf.WriteString("::1		localhost localhost.localdomain\n")
 
 		// keep extra hosts first
 		if u.id == myMeta.ID {
@@ -146,17 +146,26 @@ func (u *updater) phase2() error {
 		if err != nil {
 			return err
 		}
+		serviceHosts := make(map[string]string)
+		for ip, host := range hosts {
+			if ip == "127.0.0.1" || ip == "::1" {
+				continue
+			}
+			serviceHosts[strings.Join(host, " ")] = ip
+		}
 
 		// TODO: cut off entries for the containers in other networks
 		for ip, nwName := range u.nwNameByIPStr {
 			meta := u.metaByIPStr[ip]
 			if line := createLine(nwName, meta, myNetworks); len(line) != 0 {
-				hosts[ip] = line
+				serviceHosts[strings.Join(line, " ")] = ip
 			}
 		}
-		for ip, host := range hosts {
-			buf.WriteString(fmt.Sprintf("%-15s %s\n", ip, strings.Join(host, " ")))
+
+		for line, ip := range serviceHosts {
+			buf.WriteString(fmt.Sprintf("%-15s %s\n", ip, line))
 		}
+
 		buf.WriteString(fmt.Sprintf("# %s\n", markerEnd))
 		err = os.WriteFile(path, buf.Bytes(), 0644)
 		if err != nil {