Add binary autoupdate.

cmd/github.go

@@ -3,11 +3,75 @@ package cmd
 import (
 	"fmt"
 	"os"
+	"runtime"
 
 	gql "github.com/lukaszraczylo/simple-gql-client"
+	"github.com/melbahja/got"
 	"github.com/tidwall/gjson"
 )
 
+func updatePackage() bool {
+	ghToken, ghTokenSet := os.LookupEnv("GITHUB_TOKEN")
+	if ghTokenSet {
+		binaryName := fmt.Sprintf("semver-gen-%s-%s", runtime.GOOS, runtime.GOARCH)
+		fmt.Println("Downloading", binaryName)
+		gql.GraphQLUrl = "https://api.github.com/graphql"
+		headers := map[string]interface{}{
+			"Authorization": fmt.Sprintf("bearer %s", ghToken),
+		}
+		variables := map[string]interface{}{
+			"binaryName": binaryName,
+		}
+		var query = `query ($binaryName: String) {
+			repository(name: "semver-generator", owner: "lukaszraczylo") {
+				latestRelease {
+					releaseAssets(first: 10, name: $binaryName) {
+						edges {
+							node {
+								name
+								downloadUrl
+							}
+						}
+					}
+				}
+			}
+		}`
+		result, err := gql.Query(query, variables, headers)
+		if err != nil {
+			fmt.Println("Query error", err)
+			return false
+		}
+		result = gjson.Get(result, "repository.latestRelease.releaseAssets.edges.0.node.downloadUrl").String()
+		if result == "" {
+			fmt.Println("Unable to obtain download url for the binary", binaryName)
+			return false
+		}
+		downloadedBinaryPath := fmt.Sprintf("/tmp/%s", binaryName)
+		g := got.New()
+		err = g.Download(result, downloadedBinaryPath)
+		if err != nil {
+			fmt.Println("Unable to download binary", err.Error())
+			return false
+		}
+		currentBinary, err := os.Executable()
+		if err != nil {
+			fmt.Println("Unable to obtain current binary path", err.Error())
+			return false
+		}
+		err = os.Rename(downloadedBinaryPath, currentBinary)
+		if err != nil {
+			fmt.Println("Unable to overwrite current binary", err.Error())
+			return false
+		}
+		err = os.Chmod(currentBinary, 0777)
+		if err != nil {
+			fmt.Println("Unable to make binary executable", err.Error())
+			return false
+		}
+	}
+	return true
+}
+
 func checkLatestRelease() (string, bool) {
 	ghToken, ghTokenSet := os.LookupEnv("GITHUB_TOKEN")
 	if ghTokenSet {