学习使用 Appfile

appfile 的示例如下:

name: testapp
services:
  frontend: # 1st service
    image: oamdev/testapp:v1
    build:
      docker:
        file: Dockerfile
        context: .
    cmd: ["node", "server.js"]
    port: 8080
    route: # trait
      domain: example.com
      rules:
        - path: /testapp
          rewriteTarget: /
  backend: # 2nd service
    type: task # workload type
    image: perl 
    cmd: ["perl",  "-Mbignum=bpi", "-wle", "print bpi(2000)"]

在底层，Appfile 会从源码构建镜像，然后用镜像名称创建 application 资源

Schema

在深入学习 Appfile 的详细 schema 之前，我们建议你先熟悉 KubeVela 的核心概念

name: _app-name_
services:
  _service-name_:
    # If `build` section exists, this field will be used as the name to build image. Otherwise, KubeVela will try to pull the image with given name directly.
    image: oamdev/testapp:v1
    build:
      docker:
        file: _Dockerfile_path_ # relative path is supported, e.g. "./Dockerfile"
        context: _build_context_path_ # relative path is supported, e.g. "."
      push:
        local: kind # optionally push to local KinD cluster instead of remote registry
    type: webservice (default) | worker | task
    # detailed configurations of workload
    ... properties of the specified workload  ...
    _trait_1_:
      # properties of trait 1
    _trait_2_:
      # properties of trait 2
    ... more traits and their properties ...
  _another_service_name_: # more services can be defined
    ...

想了解怎样设置特定类型的 workload 或者 trait，请阅读参考文档手册

示例流程

在以下的流程中，我们会构建并部署一个 NodeJs 的示例 app。该 app 的源文件在这里。

环境要求

Docker 需要在主机上安装 docker
KubeVela 需要安装 KubeVela 并配置

1. 下载测试的 app 的源码

git clone 然后进入 testapp 目录:

$ git clone https://github.com/oam-dev/kubevela.git
$ cd kubevela/docs/examples/testapp

这个示例包含 NodeJs app 的源码和用于构建 app 镜像的Dockerfile

2. 使用命令部署 app

我们将会使用目录中的 vela.yaml 文件来构建和部署 app

注意：请修改 oamdev 为你自己注册的账号。或者你可以尝试 本地测试方式。

    image: oamdev/testapp:v1 # change this to your image

执行如下命令：

$ vela up
Parsing vela.yaml ...
Loading templates ...
Building service (express-server)...
Sending build context to Docker daemon  71.68kB
Step 1/10 : FROM mhart/alpine-node:12
 ---> 9d88359808c3
...
pushing image (oamdev/testapp:v1)...
...
Rendering configs for service (express-server)...
Writing deploy config to (.vela/deploy.yaml)
Applying deploy configs ...
Checking if app has been deployed...
App has not been deployed, creating a new deployment...
✅ App has been deployed 🚀🚀🚀
    Port forward: vela port-forward testapp
             SSH: vela exec testapp
         Logging: vela logs testapp
      App status: vela status testapp
  Service status: vela status testapp --svc express-server

检查服务状态：

$ vela status testapp
  About:
    Name:       testapp
    Namespace:  default
    Created at: 2020-11-02 11:08:32.138484 +0800 CST
    Updated at: 2020-11-02 11:08:32.138485 +0800 CST
  Services:
    - Name: express-server
      Type: webservice
      HEALTHY Ready: 1/1
      Last Deployment:
        Created at: 2020-11-02 11:08:33 +0800 CST
        Updated at: 2020-11-02T11:08:32+08:00
      Routes:

本地测试方式

如果你本地有运行的 kind 集群，你可以尝试推送到本地。这种方法无需注册远程容器仓库。

在 build 中添加 local 的选项值：

    build:
      # push image into local kind cluster without remote transfer
      push:
        local: kind
      docker:
        file: Dockerfile
        context: .

然后部署到 kind：

$ vela up

(进阶) 检查渲染后的 manifests 文件

默认情况下，Vela 通过 ./vela/deploy.yaml 渲染最后的 manifests 文件：

apiVersion: core.oam.dev/v1alpha2
kind: ApplicationConfiguration
metadata:
  name: testapp
  namespace: default
spec:
  components:
  - componentName: express-server
---
apiVersion: core.oam.dev/v1alpha2
kind: Component
metadata:
  name: express-server
  namespace: default
spec:
  workload:
    apiVersion: apps/v1
    kind: Deployment
    metadata:
      name: express-server
    ...
---
apiVersion: core.oam.dev/v1alpha2
kind: HealthScope
metadata:
  name: testapp-default-health
  namespace: default
spec:
  ...

[可选] 配置其他类型的 workload

至此，我们成功地部署一个默认类型的 workload 的 web 服务。我们也可以添加 Task 类型的服务到同一个 app 中。

services:
  pi:
    type: task
    image: perl 
    cmd: ["perl",  "-Mbignum=bpi", "-wle", "print bpi(2000)"]
  express-server:
    ...

然后再次部署 Applfile 来升级应用：

$ vela up

恭喜！你已经学会了使用 Appfile 来部署应用了。

下一步?

更多关于 app 的操作：