Routing router of the Docker CLI

The application framework should be known to have a routing module that looks at how Docker's HTTP requests are routed.

In Docker's Server.go file, the first entry is new.

The Func New (cfg *config) *server {//needs to create an instance of the server because the specific execution of the command is a function of the server object SRV: = &server{cfg:cfg,start:make (c Han struct{}),}//here is the operation to create the router r: = Createrouter (SRV) Srv.router = Rreturn SRV}

Let's take a look at the specifics of Createrouter.

Func createrouter (S *server)  *mux. Router {r := mux. Newrouter ()  //router relies on the third package, address: Github.com/gorilla/muxif os. Getenv ("DEBUG")  !=  " { profilersetup" (r,  "/debug/")}//MAP->MAP[STRING]HTTPAPIFUNCM  := map[string]map[string]httpapifunc{"HEAD":  {  //key,value->server corresponding processing function "/ Containers/{name:.*}/archive ":  s.headcontainersarchive,}," GET ":  {"/_ping ":                            s.ping, "/events":                          s.getevents, "/info":                             s.getinfo, "/version":     &NBsp;                    s.getversion, "/images/json":                     s.getimagesjson, "/images/search":                   s.getimagessearch, "/ Images/get ":                      s.getimagesget, "/images/{name:.*}/get":            s.getimagesget, "/images/{name:.*}/history":        s.getimageshistory, "/images/{name:.*}/json":           S.getimagesbyname, "/containers/ps":                    S.getcontainersjson, "/containers/json":                 s.getcontainersjson, "/containers/{name:.*}/export":     S.getcontainersexport, "/containers/{name:.*}/changes":    s.getcontainerschanges, "/containers/{ Name:.*}/json ":       s.getcontainersbyname,"/containers/{name:.*}/top ":        s.getcontainerstop, "/containers/{name:.*}/logs":       s.getcontainerslogs, "/containers/{name:.*}/stats":      S.getcontainersstats, "/containers/{name:.*}/attach/ws":  s.wscontainersattach, "/exec/{id:.*}/json":               s.getexecbyid, "/containers/{name :. *}/archive ":    s.getcontainersarchive,"/volumes ":               &nbsP;         s.getvolumeslist, "/volumes/{name:.*}":               s.getvolumebyname,}, "POST":  {"/ Auth ":                          s.postauth, "/commit":                         S.postcommit, "/build":                         s.postbuild, "/images/create":                 s.postimagescreate, "/images/load ":                   S.postimagesload, "/images/{name:.*}/puSH ":         s.postimagespush,"/images/{name:.*}/tag ":          s.postimagestag, "/containers/create":             s.postcontainerscreate, "/containers/{name:.*}/kill":     s.postcontainerskill, "/containers/{name:.*}/pause":    s.postcontainerspause, "/ Containers/{name:.*}/unpause ":  s.postcontainersunpause,"/containers/{name:.*}/restart ":  S.postcontainersrestart, "/containers/{name:.*}/start":    s.postcontainersstart, "/containers/{ Name:.*}/stop ":     s.postcontainersstop,"/containers/{name:.*}/wait ":     s.postcontainerswait, "/containers/{name:.*}/resize":   s.postcontainersresize, "/containers/{ Name:.*}/attach ":   s.postcontainersattach,"/containers/{name:.*}/copy ":     S.postcontainerscopy, "/containers/{name:.*}/exec":    s.postcontainerexeccreate, "/exec/{name:.*}/start":          s.postcontainerexecstart, "/exec/{name:.*}/resize":         s.postcontainerexecresize, "/containers/{name:.*}/rename":   s.postcontainerrename, "/volumes":                        s.postvolumescreate,}, "PUT":  {"/containers/{name:.*}/archive":  S.putcontainersarchive,}, "DELETE":  {"/containers/{name:.*}":  s.deletecontainers, "/images/{name:.*}":      s.deleteimages, "/volumes/{name:.*}":     s.deletevolumes,}, " OPTIONS ":  {" ": s.optionshandler,},}// if " Api-cors-header " is not given,  but  "Api-enable-cors"  is true, we set cors to  "*"//  Otherwise, all head valUes will be passed to http handlercorsheaders := s.cfg.corsheadersif  corsHeaders ==  ""  && s.cfg.EnableCors {corsHeaders =  "*"}for  method, routes := range m {for route, fct := range  Routes {logrus. DEBUGF ("registering %s, %s",  method, route)  localroute := route //For example _ pinglocalfct := fct //such as server.ping functions localmethod := method //such as "GET"//  Build the handler function//golang's Httphandlerf := makehttphandler (s.cfg.Logging,  localmethod, localroute, localfct, corsheaders, version. Version (s.cfg.version))//  here is the creation of the route if localroute ==  ""  {r.methods (Localmethod). Handlerfunc (f)} else {r.path ("/v{version:[0-9.") +} " + localroute). Methods (Localmethod). Handlerfunc (f) r.path (Localroute). Methods(Localmethod). Handlerfunc (f)}}}

Take a look at the example of the MUX:

They is defined using the format {name} or {Name:pattern}. If A regular expression pattern is not//defined, the matched variable would be anything until the next slashr: = Mux. Newrouter () R.handlefunc ("/products/{key}", Producthandler) R.handlefunc ("/articles/{category}/", Articlescategoryhandler) R.handlefunc ("/articles/{category}/{id:[0-9]+}", Articlehandler

The final MUX executes the Golang HTTP handler interface Servehttp

func  (R *router)  servehttp (w http. Responsewriter, req *http. Request)  {// Clean path to canonical form and redirect.if p  : = cleanpath (req. Url. Path);  p != req. Url. path {// added 3 lines  (philip schlump)  - it was droping  the query string and  #whatever  from query.// This matches  with fix in go 1.2 r.c. 4 for same problem.  go  Issue:// http://code.google.com/p/go/issues/detail?id=5252url := *req. Urlurl.path = pp = url. String () W.header (). Set ("Location",  p) W.writeheader (http. statusmovedpermanently) return}var match routematchvar handler http. Handlerif r.match (Req, &match)  {handler = match. handler //here is the key step Setvars (Req, match. Vars) SetcurrentroUte (Req, match. Route)}if handler == nil {handler = r.notfoundhandlerif handler ==  nil {handler = http. Notfoundhandler ()}}if !r.keepcontext {defer context. Clear (req)}handler. Servehttp (w, req)  //the anonymous function where the callback is finally executed}

Routing router of the Docker CLI