owostatus: preemptively close TCP connections

Alongside https://golang.org/pkg/net/http/#Client.CloseIdleConnections being called on every request, this should close the bodies of previous validation files to keep used ports low.

constants.go

 package main
 
-import "net/http"
-
 // DomainStatus holds a written status corresponding to a domain.
 // If you update these types, please additionally update the enum in PostgreSQL.
 type DomainStatus string
@@ -15,22 +13,4 @@ const (
 	ServiceError  DomainStatus = "service_error"
 )
 
-var UserAgent = "OwoStatusClient (https://owo.codes/spotlightishere/status.owo.cloud, 1.0.0)"
-
-func getAgentRequest(url string) (*http.Response, error) {
-	client := &http.Client{}
-
-	req, err := http.NewRequest("GET", url, nil)
-	if err != nil {
-		return nil, err
-	}
-
-	req.Header.Set("User-Agent", UserAgent)
-
-	resp, err := client.Do(req)
-	if err != nil {
-		return nil, err
-	}
-
-	return resp, nil
-}
+var UserAgent = "OwoStatusClient (https://owo.codes/spotlightishere/status.owo.cloud, 1.0.0)"
\ No newline at end of file

domain.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"fmt"
-	"io/ioutil"
 	"log"
 	"math/rand"
 	"net"
@@ -75,21 +74,16 @@ func checkDomain(hostname string) (DomainStatus, error) {
 		log.Println("Accessing", url)
 	}
 
-	resp, err := getAgentRequest(url)
+	status, body, err := getAgentRequest(url)
 	if err != nil {
 		return Misconfigured, err
 	}
 
-	if resp.StatusCode != http.StatusOK {
-		return ServiceError, fmt.Errorf("service: server responded with status %d", resp.StatusCode)
+	if status != http.StatusOK {
+		return ServiceError, fmt.Errorf("service: server responded with status %d", status)
 	}
 
-	response, err := ioutil.ReadAll(resp.Body)
-	if err != nil {
-		return ServiceError, fmt.Errorf("service: connection closed while reading file contents")
-	}
-
-	if string(response) != "1" {
+	if string(body) != "1" {
 		return ServiceError, fmt.Errorf("service: contents of file read are not what they should be")
 	}
 

domain_list.go

 package main
 
 import (
-	"io/ioutil"
+	"fmt"
 	"log"
+	"net/http"
 	"strings"
 )
 
@@ -88,14 +89,13 @@ func updateDomainList() {
 
 // populateRemoteDomainList parses the simple format used for domains remotely.
 func populateRemoteDomainList() ([]string, error) {
-	resp, err := getAgentRequest(config.General.DomainListURL)
+	status, body, err := getAgentRequest(config.General.DomainListURL)
 	if err != nil {
 		return []string{}, err
 	}
 
-	body, err := ioutil.ReadAll(resp.Body)
-	if err != nil {
-		return []string{}, err
+	if status != http.StatusOK {
+		return []string{}, fmt.Errorf("service: domain list request responded with status %d", status)
 	}
 
 	var list []string

request.go

+package main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"net/http"
+)
+
+func getAgentRequest(url string) (int, []byte, error) {
+	client := &http.Client{}
+
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return 0, nil, err
+	}
+
+	req.Header.Set("User-Agent", UserAgent)
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return 0, nil, err
+	}
+
+	statusCode := resp.StatusCode
+
+	defer resp.Body.Close()
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return 0, nil, fmt.Errorf("service: connection closed while reading file contents")
+	}
+
+	// Preemptively close idle connections to prevent ports from being clogged.
+	client.CloseIdleConnections()
+	return statusCode, body, nil
+}