improve egctl to support sending multi configs at once (fix #29) (#230)

* improve egctl to support sending multi configs at once (fix #29)

* add a visitor to do the YAML parsing

* rollback function readFromFileOrStdin

* Update comments.

Co-authored-by: Bomin Zhang <[email protected]>

* some improvements
- change the signature of VisitorFunc
- remove useless function readFromFileOrStdin

Co-authored-by: Bomin Zhang <[email protected]>

cmd/client/command/common.go

@@ -163,7 +163,7 @@ func printBody(body []byte) {
  fmt.Printf("%s", output)
 }
 
-func readFromFileOrStdin(specFile string, cmd *cobra.Command) ([]byte, string) {
+func buildVisitorFromFileOrStdin(specFile string, cmd *cobra.Command) Visitor {
  var buff []byte
  var err error
  if specFile != "" {
@@ -177,15 +177,5 @@ func readFromFileOrStdin(specFile string, cmd *cobra.Command) ([]byte, string) {
  ExitWithErrorf("%s failed: %v", cmd.Short, err)
  }
  }
-
- var spec struct {
- Kind string `yaml:"kind"`
- Name string `yaml:"name"`
- }
- err = yaml.Unmarshal(buff, &spec)
- if err != nil {
- ExitWithErrorf("%s failed, invalid spec: %v", cmd.Short, err)
- }
-
- return buff, spec.Name
+ return NewStreamVisitor(string(buff))
 }

cmd/client/command/object.go

@@ -61,8 +61,10 @@ func createObjectCmd() *cobra.Command {
  Use: "create",
  Short: "Create an object from a yaml file or stdin",
  Run: func(cmd *cobra.Command, args []string) {
- buff, _ := readFromFileOrStdin(specFile, cmd)
- handleRequest(http.MethodPost, makeURL(objectsURL), buff, cmd)
+ visitor := buildVisitorFromFileOrStdin(specFile, cmd)
+ visitor.Visit(func(s *spec) {
+ handleRequest(http.MethodPost, makeURL(objectsURL), []byte(s.doc), cmd)
+ })
  },
  }
 
@@ -77,8 +79,10 @@ func updateObjectCmd() *cobra.Command {
  Use: "update",
  Short: "Update an object from a yaml file or stdin",
  Run: func(cmd *cobra.Command, args []string) {
- buff, name := readFromFileOrStdin(specFile, cmd)
- handleRequest(http.MethodPut, makeURL(objectURL, name), buff, cmd)
+ visitor := buildVisitorFromFileOrStdin(specFile, cmd)
+ visitor.Visit(func(s *spec) {
+ handleRequest(http.MethodPost, makeURL(objectsURL), []byte(s.doc), cmd)
+ })
  },
  }
 

cmd/client/command/visitor.go

@@ -0,0 +1,80 @@
+package command
+
+import (
+ "bufio"
+ "io"
+ "strings"
+
+ "k8s.io/apimachinery/pkg/util/yaml"
+)
+
+// VisitorFunc executes visition logic
+type VisitorFunc func(*spec)
+
+// Visitor walk through the document via VisitorFunc
+type Visitor interface {
+ Visit(VisitorFunc)
+}
+
+type spec struct {
+ Kind string
+ Name string
+ doc string
+}
+
+type streamVisitor struct {
+ io.Reader
+}
+
+// NewStreamVisitor returns a streamVisitor.
+func NewStreamVisitor(src string) *streamVisitor {
+ return &streamVisitor{
+ Reader: strings.NewReader(src),
+ }
+}
+
+type yamlDecoder struct {
+ reader *yaml.YAMLReader
+ doc string
+}
+
+func newYAMLDecoder(r io.Reader) *yamlDecoder {
+ return &yamlDecoder{
+ reader: yaml.NewYAMLReader(bufio.NewReader(r)),
+ }
+}
+
+// Decode reads a YAML document into bytes and tries to yaml.Unmarshal it.
+func (d *yamlDecoder) Decode(into interface{}) error {
+ bytes, err := d.reader.Read()
+ if err != nil && err != io.EOF {
+ return err
+ }
+ d.doc = string(bytes)
+ if len(bytes) != 0 {
+ err = yaml.Unmarshal(bytes, into)
+ }
+ return err
+}
+
+// Visit implements Visitor over a stream.
+func (v *streamVisitor) Visit(fn VisitorFunc) {
+ d := newYAMLDecoder(v.Reader)
+ var validSpecs []spec
+ for {
+ var s spec
+ if err := d.Decode(&s); err != nil {
+ if err == io.EOF {
+ break
+ } else {
+ ExitWithErrorf("error parsing %s: %v", d.doc, err)
+ }
+ }
+ s.doc = d.doc
+ //TODO can validate spec's Kind here
+ validSpecs = append(validSpecs, s)
+ }
+ for _, s := range validSpecs {
+ fn(&s)
+ }
+}

cmd/client/command/wasm.go

@@ -85,8 +85,10 @@ func wasmApplyDataCmd() *cobra.Command {
  },
 
  Run: func(cmd *cobra.Command, args []string) {
- buf, _ := readFromFileOrStdin(specFile, cmd)
- handleRequest(http.MethodPut, makeURL(wasmDataURL, args[0], args[1]), buf, cmd)
+ visitor := buildVisitorFromFileOrStdin(specFile, cmd)
+ visitor.Visit(func(s *spec) {
+ handleRequest(http.MethodPost, makeURL(objectsURL), []byte(s.doc), cmd)
+ })
  },
  }
  cmd.Flags().StringVarP(&specFile, "file", "f", "", "A yaml file specifying the object.")