问题

我理解你的要求，这是翻译好的内容：

我想要向我的所有Pod（具有特定注释的）添加一个initContainer，新添加的initContainer应该是第一个initContainer。我的补丁如下所示。

```yaml
patches:
  - target:
      kind: Pod
      annotationSelector: "database_init=True"
    patch: |-
      - op: add
        path: /spec/initContainers/0
        value:
          name: database-init
          ...      

这对于已经有initContainer的所有Pod都可以正常工作。不幸的是，我有一些没有initContainer的Pod，补丁在那里失败并显示错误信息“add操作不适用：文档缺少路径：/spec/initContainers/0”。我应该如何编写一个适用于所有我的Pod的补丁？

完整示例：

.
├── base
│   ├── kustomization.yaml
│   ├── pod-1.yaml
│   └── pod-2.yaml
└── overlay
    └── kustomization.yaml

# cat base/pod-1.yaml
apiVersion: v1
kind: Pod
metadata:
  name: mypod-1
  annotations:
    database_init: True
spec:
  initContainers:
    - name: something
      image: alpine:latest
      command: ["sleep", "10"]
  containers:
    - name: main
      image: alpine:latest
      command: ["sleep", "60"]

# cat base/pod-2.yaml
apiVersion: v1
kind: Pod
metadata:
  name: mypod-2
  annotations:
    database_init: True
spec:
#   initContainers:
#     - name: something
#       image: alpine:latest
#       command: ["sleep", "10"]
  containers:
    - name: main
      image: alpine:latest
      command: ["sleep", "60"]

# cat base/kustomization.yaml
resources:
  - pod-1.yaml
  - pod-2.yaml

# cat overlay/kustomization.yaml
resources:
  - ../base

patches:

  - target:
      kind: Pod
      annotationSelector: "database_init=True"
    patch: |-
      - op: add
        path: /spec/initContainers/0
        value:
          name: database-init
          image: alpine:latest
          command: ["sleep", 10]      

结果：

$ kubectl kustomize overlay
error: add operation does not apply: doc is missing path: "/spec/initContainers/0": missing value

在取消注释pod-2的initContainer后，一切都正常工作。

编辑：添加了annotationSelector。

编辑：添加了完整示例代码。

希望这对你有所帮助！

<details>
<summary>英文:</summary>

I want to add an initContainer to all of my pods (with a specific annotation) in my kustomize base. The newly added init container should be the first init container. My patch looks like this.

patches:

• target:
  kind: Pod
  annotationSelector: "database_init=True"
  patch: |-
  • op: add
    path: /spec/initContainers/0
    value:
    name: database-init
    ...

This works fine for all pods that already have an init container. Unfortunately, I have pods without init containers and there the patch fails with the error ``add operation does not apply: doc is missing path: \"/spec/initContainers/0\"``.
How do I write a patch that works for all my pods?


Complete example:

.
├── base
│ ├── kustomization.yaml
│ ├── pod-1.yaml
│ └── pod-2.yaml
└── overlay
└── kustomization.yaml

cat base/pod-1.yaml

apiVersion: v1
kind: Pod
metadata:
name: mypod-1
annotations:
database_init: True
spec:
initContainers:
- name: something
image: alpine:latest
command: ["sleep", "10" ]
containers:
- name: main
image: alpine:latest
command: [ "sleep", "60" ]

cat base/pod-2.yaml

apiVersion: v1
kind: Pod
metadata:
name: mypod-2
annotations:
database_init: True
spec:

initContainers:

- name: something

image: alpine:latest

command: ["sleep", "10" ]

containers:
- name: main
image: alpine:latest
command: [ "sleep", "60" ]

cat base/kustomization.yaml

resources:

• pod-1.yaml
• pod-2.yaml

cat overlay/kustomization.yaml

resources:

• ../base

patches:

• target:
  kind: Pod
  annotationSelector: "database_init=True"
  patch: |-
  • op: add
    path: /spec/initContainers/0
    value:
    name: database-init
    image: alpine:latest
    command: [ "sleep", 10 ]

Result:

$ kubectl kustomize overlay
error: add operation does not apply: doc is missing path: "/spec/initContainers/0": missing value

After uncommenting the init container of pod-2, everything works.

Edit: Added the annotationSelector.

Edit: Added the complete example code.

</details>


# 答案1
**得分**: 3

JSONPatch补丁通常无法处理“追加到现有列表或创建新列表”的情况。有关详细信息，请参见[此问题](https://stackoverflow.com/q/47670366/147356)。

幸运的是，使用Kustomize 5.0.1，似乎可以通过使用战略合并补丁来实现您的目标。根据您的示例配置，在`overlay/kustomization.yaml`中放置以下内容：

```yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
- ../base/

patches:
  - target:
      kind: Pod
      annotationSelector: database_init=True
    patch: |-
      apiVersion: v1
      kind: Pod
      metadata:
        name: __ignored__
      spec:
        initContainers:
          - name: database-init
            image: alpine:latest
            command:
              - init
              - the
              - database

然后运行kustomize build overlay会产生以下输出：

apiVersion: v1
kind: Pod
metadata:
  annotations:
    database_init: "True"
  name: mypod-1
spec:
  containers:
  - command:
    - sleep
    - "60"
    image: alpine:latest
    name: main
  initContainers:
  - command:
    - init
    - the
    - database
    image: alpine:latest
    name: database-init
  - command:
    - sleep
    - "10"
    image: alpine:latest
    name: something
---
apiVersion: v1
kind: Pod
metadata:
  annotations:
    database_init: "True"
  name: mypod-2
spec:
  containers:
  - command:
    - sleep
    - "60"
    image: alpine:latest
    name: main
  initContainers:
  - command:
    - init
    - the
    - database
    image: alpine:latest
    name: database-init

apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
- ../base/

patches:
  - target:
      kind: Pod
      annotationSelector: database_init=True
    patch: |-
      apiVersion: v1
      kind: Pod
      metadata:
        name: __ignored__
      spec:
        initContainers:
          - name: database-init
            image: alpine:latest
            command:
              - init
              - the
              - database

apiVersion: v1
kind: Pod
metadata:
  annotations:
    database_init: "True"
  name: mypod-1
spec:
  containers:
  - command:
    - sleep
    - "60"
    image: alpine:latest
    name: main
  initContainers:
  - command:
    - init
    - the
    - database
    image: alpine:latest
    name: database-init
  - command:
    - sleep
    - "10"
    image: alpine:latest
    name: something
---
apiVersion: v1
kind: Pod
metadata:
  annotations:
    database_init: "True"
  name: mypod-2
spec:
  containers:
  - command:
    - sleep
    - "60"
    image: alpine:latest
    name: main
  initContainers:
  - command:
    - init
    - the
    - database
    image: alpine:latest
    name: database-init