go - 如何反序列化 Kubernetes YAML 文件

Question

如何将 Kubernetes YAML 文件反序列化为 Go 结构？我查看了kubectl代码，但不知何故，每个 YAML 文件都有一个错误：

no kind "Deployment" is registered for version "apps/v1beta1"

这是一个 MWE：

package main

import (
    "fmt"

    "k8s.io/client-go/pkg/api"
)

var service = `
apiVersion: apps/v1beta1
kind: Deployment
metadata:
  name: my-nginx
spec:
  replicas: 2
  template:
    metadata:
      labels:
        run: my-nginx
    spec:
      containers:
      - name: my-nginx
        image: nginx
        ports:
        - containerPort: 80
`

func main() {
    decode := api.Codecs.UniversalDecoder().Decode
    //decode := api.Codecs.UniversalDeserializer().Decode

    obj, _, err := decode([]byte(service), nil, nil)
    if err != nil {
        panic(err)
    }

    fmt.Printf("%#v\n", obj)
}

我正在使用客户端版本2.0.0。glide.yaml看起来像这样：

package: test/stackoverflow
import:
- package: k8s.io/client-go
  version: ^2.0.0

这些是对的参考kubectl：

不幸的是，这些文档让我很困惑，所以我不知道如何解决这个问题。

编辑：

其他资源类型也存在此问题：

no kind "Service" is registered for version "v1"

score 5 · Accepted Answer

您需要导入_ "k8s.io/client-go/pkg/apis/extensions/install"，否则架构为空，另请参阅docs。

完整的工作示例是：

$ go get -u github.com/golang/dep/cmd/dep
$ dep init
$ go run main.go

具有以下内容main.go：

package main

import (
    "fmt"

    "k8s.io/client-go/pkg/api"
    _ "k8s.io/client-go/pkg/api/install"
    _ "k8s.io/client-go/pkg/apis/extensions/install"
)

var deployment = `
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: my-nginx
spec:
replicas: 2
template:
  metadata:
    labels:
      run: my-nginx
  spec:
    containers:
    - name: my-nginx
      image: nginx
      ports:
      - containerPort: 80
`

func main() {
    // decode := api.Codecs.UniversalDecoder().Decode
    decode := api.Codecs.UniversalDeserializer().Decode

    obj, _, err := decode([]byte(deployment), nil, nil)
    if err != nil {
        fmt.Printf("%#v", err)
    }

    fmt.Printf("%#v\n", obj)
}

请注意，我还_ "k8s.io/client-go/pkg/api/install"为您导入，以便您可以在v1pod 或服务中使用对象。

编辑：向我的同事Stefan Schimanski 致敬，他提出了最初的解决方案。

score 0 · Accepted Answer

我一直在使用 api 机器k8s.io/apimachinery/pkg/util/yaml来解码 kubernete 的部署和服务清单。

import (
   "fmt"
   "bytes"
   appsv1 "k8s.io/api/apps/v1"
    k8Yaml "k8s.io/apimachinery/pkg/util/yaml"
)
...

d := &appsv1.Deployment{}
dec := k8Yaml.NewYAMLOrJSONDecoder(bytes.NewReader([]byte(deploymentManifest)), 1000)

if err := dec.Decode(&d); err != nil {
        return nil, err
}

fmt.Printf("%+v", d)

score 0 · Accepted Answer

import (
    "fmt"
    "gopkg.in/yaml.v2"
    "log"
    //corev1 "k8s.io/api/core/v1"
    "k8s.io/apimachinery/pkg/runtime/serializer/json"
    "k8s.io/client-go/kubernetes/scheme"
    v1alpha1 "github.com/argoproj/argo-cd/pkg/apis/application/v1alpha1"
)

....

func ParseYaml2(yaml []byte) (v1alpha1.Application, error) {
    // Create a YAML serializer.  JSON is a subset of YAML, so is supported too.
    s := json.NewYAMLSerializer(json.DefaultMetaFactory, scheme.Scheme,
        scheme.Scheme)

    // Decode the YAML to an object.
    var app v1alpha1.Application
    _, _, err := s.Decode(yaml, nil, &app)
    if err != nil {
        panic(err)
    }
    //fmt.Printf("%#v\n", app)
    return app, err
}
---
go.mod
// https://github.com/argoproj/argo-cd/issues/4055
replace github.com/argoproj/argo-cd => github.com/argoproj/argo-cd v1.5.5

var yaml2 = []byte(`
apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
...

var app v1alpha1.Application
app,err := ParseYaml2(yaml2)
// Types from https://github.com/argoproj/argo-cd/blob/master/pkg/apis/application/v1alpha1/types.go
    fmt.Printf("--- t:\n%s\n\n", app.Spec.Source.Path)
    fmt.Printf("--- t:\n%s\n\n", app.Spec.Source.Helm.ValueFiles)
----

go - 如何反序列化 Kubernetes YAML 文件

3 回答 3

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