caddyserver nginx adaper 简单说明

caddyserver 包含了一个强大的adapter 架构设计，我们可以方便的进行 caddyserver 扩展
nginx 扩展的处理核心也是基于adapter 模块扩展的，通过解析nginx.conf 文件，然后转换为json 格式内容

参考处理

 

func init() {

  // 注册Adapter

  caddyconfig.RegisterAdapter("nginx", Adapter{})

}

 

const ErrUnrecognized = "unrecognized or unsupported nginx directive"

const ErrNamedLocation = "named locations marked by @ are unnsupported"

const ErrExpiresAtTime = "usage of `expires @time` is not supported"

 

// Adapter adapts NGINX config to Caddy JSON.

type Adapter struct{}

// 解析nginx 配置并 转换为json 格式

// Adapt converts the NGINX config in body to Caddy JSON.

func (Adapter) Adapt(body []byte, options map[string]interface{}) ([]byte, []caddyconfig.Warning, error) {

  filename := "nginx.conf"

  if v, ok := options["filename"].(string); ok {

    filename = v

    filename, _ = filepath.Abs(filename)

  }

  // 解析nginx 的关键token

  tokens := tokenize(body, filename)

 // 解析nginx 指令

  dirs, err := parse(tokens)

  if err != nil {

    return nil, nil, fmt.Errorf("parsing: %v", err)

  }

 

  ss := setupState{

    servers: make(map[string]*caddyhttp.Server),

  }

 

  warnings, err := ss.mainContext(dirs)

  if err != nil {

    return nil, nil, err

  }

 

  httpApp := caddyhttp.App{

    Servers: ss.servers,

  }

 

  ss.mainConfig.AppsRaw = map[string]json.RawMessage{

    "http": caddyconfig.JSON(httpApp, &warnings),

  }

 

  result, err := json.Marshal(ss.mainConfig)

 

  return result, warnings, err

}

nginx 解析处理

parse.go 以及lexer.go 中处理上还是值得学习的，部分应该也参考了部分社区的golang nginx 解析工具
转换caddy 配置处理,实际解析都会处理为标准的caddy.Config

 

func (ss *setupState) mainContext(dirs []Directive) ([]caddyconfig.Warning, error) {

  var warnings []caddyconfig.Warning

  for _, dir := range dirs {

    var warns []caddyconfig.Warning

    var err error

    switch dir.Name() {

    case "http":

      warns, err = ss.httpContext(dir.Block)

    default:

      warns = []caddyconfig.Warning{

        {

          File:      dir.File,

          Line:      dir.Line,

          Directive: dir.Name(),

          Message:   ErrUnrecognized,

        },

      }

    }

    warnings = append(warnings, warns...)

    if err != nil {

      return warnings, err

    }

  }

  return warnings, nil

}

 

func (ss *setupState) httpContext(dirs []Directive) ([]caddyconfig.Warning, error) {

  var warnings []caddyconfig.Warning

  for _, dir := range dirs {

    var warns []caddyconfig.Warning

    var err error

    switch dir.Name() {

    case "index":

      for k, d := range dirs {

        if d.Name() == "server" {

          dirs[k].Block = append(d.Block, dir)

        }

      }

    case "server":

      warns, err = ss.serverContext(dir.Block)

    case "upstream":

      up, w, err := ss.upstreamContext(dir.Block)

      warns = append(warns, w...)

      if err != nil {

        return warns, err

      }

      if ss.upstreams == nil {

        ss.upstreams = make(map[string]Upstream)

      }

      ss.upstreams[dir.Param(1)] = up

    default:

      warns = []caddyconfig.Warning{

        {

          File:      dir.File,

          Line:      dir.Line,

          Directive: dir.Name(),

          Message:   ErrUnrecognized,

        },

      }

    }

    warnings = append(warnings, warns...)

    if err != nil {

      return warnings, err

    }

  }

  return warnings, nil

}

server 处理的 (server.go 中)会转换为标准caddy 配置的监听，路由等处理，详细的可以参考

说明

caddyserver nginx adaper 核心还是将nignx 配置转换为json 格式，之后caddy 会按照标准 adaper 模式进行加载，注意实际使用的时候需要自己构建
可以使用xcaddy 构建工具

参考资料

nginxadapter.go
https://github.com/caddyserver/nginx-adapter
https://caddyserver.com/docs/json/apps/http/
https://caddyserver.com/docs/config-adapters
https://caddyserver.com/docs/extending-caddy/config-adapters
https://caddyserver.com/docs/architecture
https://github.com/recoye/config
https://github.com/yangchenxing/go-nginx-conf-parser
https://www.nginx.com/resources/wiki/start/topics/examples/full/
https://github.com/caddyserver/xcaddy