Add new api usage mechanism.

cmd/cloudcfg/cloudcfg.go

@@ -139,27 +139,34 @@ func executeAPIRequest(method string, auth *kube_client.AuthInfo) bool {
 		return *httpServer + path.Join("/api/v1beta1", storage)
 	}
 
-	var request *http.Request
-	var err error
+	verb := ""
 	switch method {
 	case "get", "list":
-		url := readUrl(parseStorage())
-		if len(*selector) > 0 && method == "list" {
-			url = url + "?labels=" + *selector
-		}
-		request, err = http.NewRequest("GET", url, nil)
+		verb = "GET"
 	case "delete":
-		request, err = http.NewRequest("DELETE", readUrl(parseStorage()), nil)
+		verb = "DELETE"
 	case "create":
-		storage := parseStorage()
-		request, err = cloudcfg.RequestWithBodyData(readConfig(storage), readUrl(storage), "POST")
+		verb = "POST"
 	case "update":
-		storage := parseStorage()
-		request, err = cloudcfg.RequestWithBodyData(readConfig(storage), readUrl(storage), "PUT")
+		verb = "PUT"
 	default:
 		return false
 	}
 
+	s := cloudcfg.New(*httpServer, auth)
+	r := s.Verb(verb).
+		Path("api/v1beta1").
+		Path(parseStorage()).
+		Selector(*selector)
+	if method == "create" || method == "update" {
+		r.Body(readConfig(parseStorage()))
+	}
+	obj, err := r.Do()
+	if err != nil {
+		log.Fatalf("Got request error: %v\n", err)
+		return false
+	}
+
 	var printer cloudcfg.ResourcePrinter
 	if *json {
 		printer = &cloudcfg.IdentityPrinter{}
@@ -169,15 +176,10 @@ func executeAPIRequest(method string, auth *kube_client.AuthInfo) bool {
 		printer = &cloudcfg.HumanReadablePrinter{}
 	}
 
-	var body []byte
-	if body, err = cloudcfg.DoRequest(request, auth); err == nil {
-		if err = printer.Print(body, os.Stdout); err != nil {
-			log.Fatalf("Failed to print: %#v\nRaw received text:\n%v\n", err, string(body))
-		}
-		fmt.Print("\n")
-	} else {
-		log.Fatalf("Error: %#v %s", err, body)
+	if err = printer.PrintObj(obj, os.Stdout); err != nil {
+		log.Fatalf("Failed to print: %#v\nRaw received text:\n%v\n", err, string(body))
 	}
+	fmt.Print("\n")
 
 	return true
 }

pkg/cloudcfg/cloudcfg.go

@@ -21,16 +21,20 @@ import (
 	"crypto/tls"
 	"encoding/json"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"log"
 	"net/http"
+	"net/url"
 	"os"
+	"path"
 	"strconv"
 	"strings"
 	"time"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/client"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/labels"
 	"gopkg.in/v1/yaml"
 )
 
@@ -90,6 +94,132 @@ func Update(name string, client client.ClientInterface, updatePeriod time.Durati
 	return nil
 }
 
+// Server contains info locating a kubernetes api server.
+// Example usage:
+// auth, err := LoadAuth(filename)
+// s := New(url, auth)
+// resp, err := s.Verb("GET").
+//	Path("api/v1beta1").
+//	Path("pods").
+//	Selector("area=staging").
+//	Timeout(10*time.Second).
+//	Do()
+// list, ok := resp.(api.PodList)
+type Server struct {
+	auth   *client.AuthInfo
+	rawUrl string
+}
+
+// Create a new server object.
+func New(serverUrl string, auth *client.AuthInfo) *Server {
+	return &Server{
+		auth:   auth,
+		rawUrl: serverUrl,
+	}
+}
+
+// Begin a request with a verb (GET, POST, PUT, DELETE)
+func (s *Server) Verb(verb string) *Request {
+	return &Request{
+		verb: verb,
+		s:    s,
+	}
+}
+
+// Request allows for building up a request to a server in a chained fashion.
+type Request struct {
+	s        *Server
+	err      error
+	verb     string
+	path     string
+	body     interface{}
+	selector labels.Selector
+	timeout  time.Duration
+}
+
+// Append an item to the request path. You must call Path at least once.
+func (r *Request) Path(item string) *Request {
+	if r.err != nil {
+		return r
+	}
+	r.path = path.Join(r.path, item)
+	return r
+}
+
+// Use the given item as a resource label selector. Optional.
+func (r *Request) Selector(item string) *Request {
+	if r.err != nil {
+		return r
+	}
+	r.selector, r.err = labels.ParseSelector(item)
+	return r
+}
+
+// Use the given duration as a timeout. Optional.
+func (r *Request) Timeout(d time.Duration) *Request {
+	if r.err != nil {
+		return r
+	}
+	r.timeout = d
+	return r
+}
+
+// Use obj as the body of the request. Optional.
+// If obj is a string, try to read a file of that name.
+// If obj is a []byte, send it directly.
+// Otherwise, assume obj is an api type and marshall it correctly.
+func (r *Request) Body(obj interface{}) *Request {
+	if r.err != nil {
+		return r
+	}
+	r.body = obj
+	return r
+}
+
+// Format and xecute the request. Returns the API object received, or an error.
+func (r *Request) Do() (interface{}, error) {
+	if r.err != nil {
+		return nil, r.err
+	}
+	finalUrl := path.Join(r.s.rawUrl, r.path)
+	query := url.Values{}
+	if r.selector != nil {
+		query.Add("labels", r.selector.String())
+	}
+	if r.timeout != 0 {
+		query.Add("timeout", r.timeout.String())
+	}
+	finalUrl += "?" + query.Encode()
+	var body io.Reader
+	if r.body != nil {
+		switch t := r.body.(type) {
+		case string:
+			data, err := ioutil.ReadFile(t)
+			if err != nil {
+				return nil, err
+			}
+			body = bytes.NewBuffer(data)
+		case []byte:
+			body = bytes.NewBuffer(t)
+		default:
+			data, err := api.Encode(r.body)
+			if err != nil {
+				return nil, err
+			}
+			body = bytes.NewBuffer(data)
+		}
+	}
+	req, err := http.NewRequest(r.verb, finalUrl, body)
+	if err != nil {
+		return nil, err
+	}
+	str, err := DoRequest(req, r.s.auth)
+	if err != nil {
+		return nil, err
+	}
+	return api.Decode([]byte(str))
+}
+
 // RequestWithBody is a helper method that creates an HTTP request with the specified url, method
 // and a body read from 'configFile'
 // FIXME: need to be public API?

pkg/cloudcfg/resource_printer.go

@@ -32,6 +32,7 @@ import (
 type ResourcePrinter interface {
 	// Print receives an arbitrary JSON body, formats it and prints it to a writer
 	Print([]byte, io.Writer) error
+	PrintObj(interface{}, io.Writer)
 }
 
 // Identity printer simply copies the body out to the output stream
@@ -42,6 +43,14 @@ func (i *IdentityPrinter) Print(data []byte, w io.Writer) error {
 	return err
 }
 
+func (i *IdentityPrinter) PrintObj(obj interface{}, output io.Writer) error {
+	data, err := api.EncodeIndent(obj)
+	if err != nil {
+		return err
+	}
+	return i.Print(data, output)
+}
+
 // YAMLPrinter parses JSON, and re-formats as YAML
 type YAMLPrinter struct{}
 
@@ -58,6 +67,15 @@ func (y *YAMLPrinter) Print(data []byte, w io.Writer) error {
 	return err
 }
 
+func (y *YAMLPrinter) PrintObj(obj interface{}, w io.Writer) error {
+	output, err := yaml.Marshal(obj)
+	if err != nil {
+		return err
+	}
+	_, err = fmt.Fprint(w, string(output))
+	return err
+}
+
 // HumanReadablePrinter attempts to provide more elegant output
 type HumanReadablePrinter struct{}
 
@@ -168,6 +186,10 @@ func (h *HumanReadablePrinter) Print(data []byte, output io.Writer) error {
 	if err != nil {
 		return err
 	}
+	return h.PrintObj(obj, output)
+}
+
+func (h *HumanReadablePrinter) PrintObj(obj interface{}, output io.Writer) {
 	switch o := obj.(type) {
 	case *api.Pod:
 		h.printHeader(podColumns, w)