feat(http): generate client build number instead of hardcoding it

internal/http/generated.go

@@ -0,0 +1,5 @@
+// GENERATED BY go generate; DO NOT EDIT.
+
+package http
+
+const ClientBuildNumber = 562538

internal/http/generator.go

@@ -0,0 +1,66 @@
+//go:build ignore
+
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"regexp"
+
+	"github.com/diamondburned/arikawa/v3/api"
+)
+
+const format = `// GENERATED BY go generate; DO NOT EDIT.
+
+package %s
+
+const ClientBuildNumber = %s
+`
+
+var buildNumberRegex = regexp.MustCompile(`"BUILD_NUMBER":\s*"(\d+)"`)
+
+func fetchBuildNumber() (string, error) {
+	resp, err := http.Get(api.BaseEndpoint + "/login")
+	if err != nil {
+		return "", err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode < http.StatusOK || resp.StatusCode >= http.StatusMultipleChoices {
+		return "", fmt.Errorf("failed to fetch login page; status=%q", resp.Status)
+	}
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return "", err
+	}
+
+	matches := buildNumberRegex.FindSubmatch(body)
+	if len(matches) < 2 {
+		return "", fmt.Errorf("failed to find build number; matches=%v", matches)
+	}
+	return string(matches[1]), nil
+}
+
+func main() {
+	out := flag.String("out", "generated.go", "out filename")
+	flag.Parse()
+
+	buildNumber, err := fetchBuildNumber()
+	if err != nil {
+		panic(err)
+	}
+
+	packageName := os.Getenv("GOPACKAGE")
+	if packageName == "" {
+		panic("GOPACKAGE is not set; run with go generate")
+	}
+
+	content := fmt.Appendf(nil, format, packageName, buildNumber)
+	if err := os.WriteFile(*out, content, 0644); err != nil {
+		panic(err)
+	}
+}

internal/http/headers.go

@@ -3,6 +3,8 @@ package http
 import (
 	"log/slog"
 	stdHttp "net/http"
+
+	"github.com/diamondburned/arikawa/v3/api"
 )
 
 func Headers() stdHttp.Header {
@@ -11,9 +13,10 @@ func Headers() stdHttp.Header {
 	headers.Set("Accept", "*/*")
 	headers.Set("Accept-Encoding", "gzip, deflate, br, zstd")
 	headers.Set("Accept-Language", "en-US,en;q=0.9")
-	headers.Set("Origin", "https://discord.com")
+	headers.Set("Origin", api.BaseEndpoint)
 	headers.Set("Priority", "u=0, i")
 	headers.Set("Referer", "https://discord.com/channels/@me")
+
 	headers.Set("Sec-Fetch-Dest", "empty")
 	headers.Set("Sec-Fetch-Mode", "cors")
 	headers.Set("Sec-Fetch-Site", "same-origin")

internal/http/props.go

@@ -9,6 +9,8 @@ import (
 	"github.com/google/uuid"
 )
 
+//go:generate go run generator.go
+
 const (
 	OS        = "Windows"
 	OSVersion = "10"
@@ -17,8 +19,7 @@ const (
 	BrowserVersion   = "143.0.0.0"
 	BrowserUserAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) " + Browser + "/" + BrowserVersion + " Safari/537.36"
 
-	ClientBuildNumber = 482285
-	Locale            = discord.EnglishUS
+	Locale = discord.EnglishUS
 )
 
 func IdentifyProperties() gateway.IdentifyProperties {