使用脚本安装和升级Golang

这是一个很好的PowerShell脚本，用于在Windows上管理Go语言的安装和升级。不过，我注意到几个可以改进的地方：

主要问题：

1. 下载逻辑缺失：脚本中注释掉了实际的下载代码
2. 版本检测可能不准确：从release分支名提取版本号可能不是最佳方式
3. 路径处理需要调整：解压路径可能需要修正

改进后的脚本示例：

Write-Output "Welcome to GO lang portable installation script"
Write-Output "Written by: Hasan A Yousef, Aug 2020"
Write-Output "Modified with improvements"
Write-Output "=============================================="
Write-Output "GO lang SDK will be installed at C:\go\bin"
Write-Output "GO lang (GOPATH) will be set as 'Documents\GoWorkPlace'"
Write-Output ""

function InstallGo {
    param (
        $latest_version,
        $workDir
    )
    
    $file = "go$latest_version.windows-amd64.zip"
    $path = 'C:\go'
    $url = "https://golang.org/dl/$file"
    $dest = Join-Path $Home "Downloads\$file"
    
    # 清理旧版本
    if (Test-Path $path) {
        Write-Output "Removing the currently installed Go from $path"
        Remove-Item "$path\*" -Recurse -Force
    } else {
        Write-Output "Creating the directory required for GO installation: $path"
        New-Item -ItemType Directory -Force -Path $path | Out-Null
    }
    
    # 下载Go
    Write-Output "Downloading $url"
    try {
        Invoke-WebRequest -Uri $url -OutFile $dest
        Write-Output "Download completed: $dest"
    } catch {
        Write-Error "Failed to download Go: $_"
        return
    }
    
    # 解压文件
    Write-Output "Extracting $file to $path"
    try {
        # 确保目标目录存在
        if (!(Test-Path $path)) {
            New-Item -ItemType Directory -Force -Path $path | Out-Null
        }
        
        # 使用正确的解压方法
        Add-Type -AssemblyName System.IO.Compression.FileSystem
        [System.IO.Compression.ZipFile]::ExtractToDirectory($dest, $path)
        Write-Output "Extraction completed"
    } catch {
        Write-Error "Failed to extract Go: $_"
        return
    }
    
    # 添加到PATH
    $addPath = 'C:\go\bin'
    $currentPath = [Environment]::GetEnvironmentVariable("PATH", "User")
    
    if ($currentPath -notlike "*$addPath*") {
        $newPath = "$currentPath;$addPath"
        [Environment]::SetEnvironmentVariable("PATH", $newPath, "User")
        Write-Output "$addPath has been added to PATH"
    } else {
        Write-Output "$addPath is already in PATH"
    }
    
    # 设置环境变量
    [Environment]::SetEnvironmentVariable("GOROOT", "C:\go", "User")
    
    $gopath = Join-Path $Home $workDir
    [Environment]::SetEnvironmentVariable("GOPATH", $gopath, "User")
    
    # 创建工作空间
    if (!(Test-Path $gopath)) {
        New-Item -ItemType Directory -Force -Path $gopath | Out-Null
        Write-Output "Go workspace created: $gopath"
    } else {
        Write-Output "Go workspace already exists: $gopath"
    }
    
    Write-Output "=============================================="
    Write-Output "Go installation completed"
    
    # 刷新当前会话的PATH
    $env:Path = [Environment]::GetEnvironmentVariable("PATH", "User") + ";" + [Environment]::GetEnvironmentVariable("PATH", "Machine")
    
    # 验证安装
    try {
        go version
    } catch {
        Write-Warning "Go command not found in current session. Please restart your terminal."
    }
}

# 获取最新版本 - 改进的方法
function Get-LatestGoVersion {
    try {
        # 从官方页面获取最新版本
        $response = Invoke-WebRequest -Uri "https://golang.org/dl/" -UseBasicParsing
        $content = $response.Content
        
        # 查找Windows amd64 zip文件的版本
        $pattern = 'go(\d+\.\d+(?:\.\d+)?)\.windows-amd64\.zip'
        $matches = [regex]::Matches($content, $pattern)
        
        if ($matches.Count -gt 0) {
            $versions = $matches | ForEach-Object { $_.Groups[1].Value }
            # 按版本号排序并获取最新
            $latest = $versions | Sort-Object { [version]$_ } | Select-Object -Last 1
            return $latest
        }
    } catch {
        Write-Warning "Failed to fetch latest version: $_"
    }
    
    return $null
}

# 主执行逻辑
$workDir = 'Documents\GoWorkPlace'
$latest_version = Get-LatestGoVersion

if (-not $latest_version) {
    Write-Error "Could not determine latest Go version"
    exit 1
}

Write-Output "Latest GO lang version is: $latest_version"

# 检查已安装版本
try {
    $goVersionOutput = go version 2>&1
    if ($LASTEXITCODE -eq 0) {
        $match = [regex]::Match($goVersionOutput, 'go(\d+\.\d+(?:\.\d+)?)')
        if ($match.Success) {
            $current_version = $match.Groups[1].Value
            
            if ($current_version -eq $latest_version) {
                Write-Output "You already have the latest Go version installed: $current_version"
                exit 0
            } else {
                Write-Output "Current version: $current_version, Latest version: $latest_version"
                Write-Output "Upgrading Go..."
                InstallGo -latest_version $latest_version -workDir $workDir
            }
        }
    }
} catch {
    Write-Output "Go is not installed. Performing fresh installation..."
    InstallGo -latest_version $latest_version -workDir $workDir
}

主要改进：

1. 修复了下载功能：取消了注释，添加了错误处理
2. 改进了版本检测：直接从Go官网解析最新版本
3. 修正了解压逻辑：使用.NET的ZipFile类确保正确解压
4. 添加了错误处理：对关键操作添加了try-catch
5. 改进了PATH更新：更可靠地检测和更新PATH变量
6. 添加了安装验证：安装后验证Go命令是否可用

这个脚本现在应该能更可靠地工作。注意：由于Go官网可能需要代理访问，如果在中国大陆使用，可能需要将golang.org/dl/替换为golang.google.cn/dl/。