ODO and Rancher Desktop

odo is a fast, iterative and straightforward CLI tool for developers who write, build, and deploy applications on Kubernetes. The odo CLI abstracts away complex Kubernetes concepts and allows developers to focus on iterating code. The helper tool can detect changes to local code and deploy them to a container orchestrated cluster automatically, giving instant feedback to validate changes in real-time. Please refer to the odo project documentation to learn more.

Prerequisites

For this guide you will use the express-sample node.js application in the Rancher Desktop documentation repository as a way to demonstrate the use of odo and Rancher Desktop.

备注

odo works with the dockerd (moby) runtime, be sure to have it selected from the preferences dialog location Preferences > Container Engine > Allowed Images.

Please ensure that Kubernetes is enabled for your application. Additionally, in order to use odo deploy, you will need to be able to build and push an image to a Docker container registry. Log in using your Docker credentials as noted below:

$ docker login docker.io
Username:
Password:
Login Succeeded!

Installation

Install odo by visiting https://odo.dev/docs/overview/installation and perform the appropriate install for your platform. The tool can be used both as a CLI tool or an IDE plugin, as well as a few alternative install methods depending on your preference. This guide will focus on using the tool through the CLI.

Steps: odo init

This command will initialize the application by creating a devfile.yaml for deployments.

1. Clone the Rancher Desktop documentation repository and change your directory to the sample-express application.

git clone https://github.com/rancher-sandbox/docs.rancherdesktop.io.git
cd docs.rancherdesktop.io/assets/express-sample

1. Before initializing, you must connect odo to your cluster via a namespace, which can be created with the command odo create namespace :

odo create namespace odo-dev

Sample Output

$ odo create namespace odo-dev
 ✓  Creating the namespace "odo-dev" [5ms]
 ✓  Namespace "odo-dev" is ready for use
 ✓  New namespace created and now using namespace: odo-dev

1. The command odo init will auto-detect your project framework and choose the appropriate devfile.yaml to be used for deployment of your application. The command will allow you to confirm the Devfile (Y/n), select a container to change configuration (choose none for this example), and enter a component name (e.g. my-nodejs-app).

   Alternatively, the following command with the additional flags (e.g. --devfile-version 2.2.0) can be used to initialize odo and allow your application to be deployed:

odo init --name my-nodejs-app --devfile nodejs --devfile-registry DefaultDevfileRegistry --devfile-version 2.2.0

Sample Output

  __
 /  \__     Initializing a new component
 \__/  \    
 /  \__/    odo version: v3.13.0
 \__/
 ✓  Downloading devfile "nodejs:2.2.0" from registry "DefaultDevfileRegistry" [1s]
Your new component 'my-nodejs-app' is ready in the current directory.
To start editing your component, use 'odo dev' and open this folder in your favorite IDE.
Changes will be directly reflected on the cluster.

odo init

Sample Output

$ odo init
  __
 /  \__     Initializing a new component
 \__/  \    Files: Source code detected, a Devfile will be determined based upon source code autodetection
 /  \__/    odo version: v3.13.0
 \__/
Interactive mode enabled, please answer the following questions:
 ✓  Determining a Devfile for the current directory [910ms]
Based on the files in the current directory odo detected
Language: JavaScript
Project type: Node.js
Application ports: 3000
The devfile "nodejs:2.1.1" from the registry "DefaultDevfileRegistry" will be downloaded.
? Is this correct? Yes
 ✓  Downloading devfile "nodejs:2.1.1" from registry "DefaultDevfileRegistry" [933ms]
↪ Container Configuration "runtime":
  OPEN PORTS:
    - 3000
    - 5858
  ENVIRONMENT VARIABLES:
    - DEBUG_PORT = 5858
? Select container for which you want to change configuration? NONE - configuration is correct
? Enter component name: my-nodejs-app
You can automate this command by executing:
   odo init --name my-nodejs-app --devfile nodejs --devfile-registry DefaultDevfileRegistry --devfile-version 2.1.1
Your new component 'my-nodejs-app' is ready in the current directory.
To start editing your component, use 'odo dev' and open this folder in your favorite IDE.
Changes will be directly reflected on the cluster.

Steps: odo dev

Now, you can run the command odo dev to continuously deploy applications as you make changes to your code through your preferred IDE.

警告

You may run into an ErrImagePull error as the image may not be covered by Rancher Desktop’s allowed images list. To resolve the error, please add the necessary image in Preferences > Container Engine > Allowed Images and hit apply to update allowed images immediately.

odo dev

Sample Output

$ odo dev
  __
 /  \__     Developing using the "my-nodejs-app" Devfile
 \__/  \    Namespace: odo-dev
 /  \__/    odo version: v3.13.0
 \__/
↪ Running on the cluster in Dev mode
I0728 13:50:53.115137   92567 starterserver.go:123] API Server started at localhost:20000/api/v1
 •  Waiting for Kubernetes resources  ...
 ⚠  Pod is Pending
 ✓  Pod is Running
 ✓  Syncing files into the container [306ms]
 ✓  Building your application in container (command: install) [3s]
 •  Executing the application (command: run)  ...
 ✓  Waiting for the application to be ready [1s]
 -  Forwarding from 127.0.0.1:20001 -> 3000
↪ Dev mode
 Status:
 Watching for changes in the current directory /Users/docs.rancherdesktop.io/assets/express-sample
 Keyboard Commands:
[Ctrl+c] - Exit and delete resources from the cluster
     [p] - Manually apply local changes to the application on the cluster

The express-sample application can now be accessed by the local port (127.0.0.1:20001). As an example, you can make a text change to the index.jade file in the views folder to see a real-time update to the application.

Steps: odo deploy

This command will deploy your application to your cluster with instructions from your devfile.yaml.

1. Be sure to be logged into the Docker container registry to push the application to, and set your container image build arguments to be the same as your container architecture using the ODO_IMAGE_BUILD_ARGS environment variable:

• AMD64
• ARM

export ODO_IMAGE_BUILD_ARGS="--platform=linux/amd64"

export ODO_IMAGE_BUILD_ARGS="--platform=linux/arm64"

1. Update the Dockerfile in the express-sample directory to containerize the application with correct variables in order to build and push to a registry:

Sample Dockerfile

# Install the app dependencies in a full SLE Node image
FROM registry.suse.com/bci/nodejs:16
# Copy package.json and package-lock.json
COPY package*.json ./
# Install app dependencies
RUN npm install --production
# Install app dependencies
COPY . /opt/app-root/src
ENV NODE_ENV production
ENV PORT 3000
CMD ["npm", "start"]

1. Modify the devfile.yaml to the example noted below for your container cluster.

• Update the variables to access your container registry:

# Add the following variables code anywhere in devfile.yaml
# This MUST be a container registry you are able to access
variables:
  CONTAINER_IMAGE: docker.io/<INSERTUSERNAME>/nodejs-odo-example
  RESOURCE_NAME: my-nodejs-app
  CONTAINER_PORT: "3000"
  DOMAIN_NAME: nodejs.example.com

• Update the Devfile schema to 2.2.0 as odo deploy makes use of this version. Additionally, there is a command to initialize odo with the correct schemaVersion: 2.2.0 noted above in the installation:

# Deploy "kind" ID's use schema 2.2.0+
schemaVersion: 2.2.0

• The commands seen below are used for deployment activities:

Deployment Commands

# This is the main "composite" command that will run all below commands
commands:
- id: deploy
  composite:
    commands:
    - build-image
    - k8s-deployment
    - k8s-service
    - k8s-url
    group:
      isDefault: true
      kind: deploy
# Below are the commands and their respective components that they are "linked" to deploy
- id: build-image
  apply:
    component: outerloop-build
- id: k8s-deployment
  apply:
    component: outerloop-deployment
- id: k8s-service
  apply:
    component: outerloop-service
- id: k8s-url
  apply:
    component: outerloop-url

• The commands seen below are used for adding the Docker image location, K8s deployment and services to components:

Component Commands

# This will build the container image before deployment
- name: outerloop-build
  image:
    dockerfile:
      buildContext: ${PROJECT_SOURCE}
      rootRequired: false
      uri: ./Dockerfile
    imageName: "{{CONTAINER_IMAGE}}"
# This will create a Deployment in order to run your container image across
# the cluster.
- name: outerloop-deployment
  kubernetes:
    inlined: |
      kind: Deployment
      apiVersion: apps/v1
      metadata:
        name: {{RESOURCE_NAME}}
      spec:
        replicas: 1
        selector:
          matchLabels:
            app: {{RESOURCE_NAME}}
        template:
          metadata:
            labels:
              app: {{RESOURCE_NAME}}
          spec:
            containers:
              - name: {{RESOURCE_NAME}}
                image: {{CONTAINER_IMAGE}}
                ports:
                  - name: http
                    containerPort: {{CONTAINER_PORT}}
                    protocol: TCP
                resources:
                  limits:
                    memory: "1024Mi"
                    cpu: "500m"
# This will create a Service so your Deployment is accessible.
# Depending on your cluster, you may modify this code so it's a
# NodePort, ClusterIP or a LoadBalancer service.
- name: outerloop-service
  kubernetes:
    inlined: |
      apiVersion: v1
      kind: Service
      metadata:
        name: {{RESOURCE_NAME}}
      spec:
        ports:
        - name: "{{CONTAINER_PORT}}"
          port: {{CONTAINER_PORT}}
          protocol: TCP
          targetPort: {{CONTAINER_PORT}}
        selector:
          app: {{RESOURCE_NAME}}
        type: NodePort

• The last addition to our Devfile is adding the Kubernetes ingress component as noted below:

Ingress Commands

- name: outerloop-url
  kubernetes:
    inlined: |
      apiVersion: networking.k8s.io/v1
      kind: Ingress
      metadata:
        name: {{RESOURCE_NAME}}
      spec:
        rules:
          - host: "{{DOMAIN_NAME}}"
            http:
              paths:
                - path: "/"
                  pathType: Prefix
                  backend:
                    service:
                      name: {{RESOURCE_NAME}}
                      port:
                        number: {{CONTAINER_PORT}}

• Below is the example devfile.yaml that you can use to help illustrate command and variable settings after they are all put together. Please review your Devfile to match or update the appropriate variables as noted below:

Final Devfile

commands:
- exec:
    commandLine: npm install
    component: runtime
    group:
      isDefault: true
      kind: build
    workingDir: ${PROJECT_SOURCE}
  id: install
- exec:
    commandLine: npm start
    component: runtime
    group:
      isDefault: true
      kind: run
    workingDir: ${PROJECT_SOURCE}
  id: run
- exec:
    commandLine: npm run debug
    component: runtime
    group:
      isDefault: true
      kind: debug
    workingDir: ${PROJECT_SOURCE}
  id: debug
- exec:
    commandLine: npm test
    component: runtime
    group:
      isDefault: true
      kind: test
    workingDir: ${PROJECT_SOURCE}
  id: test
# This is the main "composite" command that will run all below commands
- id: deploy
  composite:
    commands:
    - build-image
    - k8s-deployment
    - k8s-service
    - k8s-url
    group:
      isDefault: true
      kind: deploy
# Below are the commands and their respective components that they are "linked" to deploy
- id: build-image
  apply:
    component: outerloop-build
- id: k8s-deployment
  apply:
    component: outerloop-deployment
- id: k8s-service
  apply:
    component: outerloop-service
- id: k8s-url
  apply:
    component: outerloop-url
components:
- container:
    args:
    - tail
    - -f
    - /dev/null
    endpoints:
    - name: http-node
      targetPort: 3000
    - exposure: none
      name: debug
      targetPort: 5858
    env:
    - name: DEBUG_PORT
      value: "5858"
    image: registry.suse.com/bci/nodejs:16:latest
    memoryLimit: 1024Mi
    mountSources: true
  name: runtime
# This will build the container image before deployment
- name: outerloop-build
  image:
    dockerfile:
      buildContext: ${PROJECT_SOURCE}
      rootRequired: false
      uri: ./Dockerfile
    imageName: "{{CONTAINER_IMAGE}}"
# This will create a Deployment in order to run your container image across
# the cluster.
- name: outerloop-deployment
  kubernetes:
    inlined: |
      kind: Deployment
      apiVersion: apps/v1
      metadata:
        name: {{RESOURCE_NAME}}
      spec:
        replicas: 1
        selector:
          matchLabels:
            app: {{RESOURCE_NAME}}
        template:
          metadata:
            labels:
              app: {{RESOURCE_NAME}}
          spec:
            containers:
              - name: {{RESOURCE_NAME}}
                image: {{CONTAINER_IMAGE}}
                ports:
                  - name: http
                    containerPort: {{CONTAINER_PORT}}
                    protocol: TCP
                resources:
                  limits:
                    memory: "1024Mi"
                    cpu: "500m"
# This will create a Service so your Deployment is accessible.
# Depending on your cluster, you may modify this code so it's a
# NodePort, ClusterIP or a LoadBalancer service.
- name: outerloop-service
  kubernetes:
    inlined: |
      apiVersion: v1
      kind: Service
      metadata:
        name: {{RESOURCE_NAME}}
      spec:
        ports:
        - name: "{{CONTAINER_PORT}}"
          port: {{CONTAINER_PORT}}
          protocol: TCP
          targetPort: {{CONTAINER_PORT}}
        selector:
          app: {{RESOURCE_NAME}}
        type: NodePort
- name: outerloop-url
  kubernetes:
    inlined: |
      apiVersion: networking.k8s.io/v1
      kind: Ingress
      metadata:
        name: {{RESOURCE_NAME}}
      spec:
        rules:
          - host: "{{DOMAIN_NAME}}"
            http:
              paths:
                - path: "/"
                  pathType: Prefix
                  backend:
                    service:
                      name: {{RESOURCE_NAME}}
                      port:
                        number: {{CONTAINER_PORT}}
metadata:
  description: Stack with Node.js 16
  displayName: Node.js Runtime
  icon: https://nodejs.org/static/images/logos/nodejs-new-pantone-black.svg
  language: JavaScript
  name: my-node-app
  projectType: Node.js
  tags:
  - Node.js
  - Express
  - ubi8
  version: 2.1.1
schemaVersion: 2.2.0
starterProjects:
- git:
    remotes:
      origin: https://github.com/odo-devfiles/nodejs-ex.git
  name: nodejs-starter
# Add the following variables code anywhere in devfile.yaml
# This MUST be a container registry you are able to access
variables:
  CONTAINER_IMAGE: docker.io/<INSERTUSERNAME>/node-odo-example
  RESOURCE_NAME: my-node-app
  CONTAINER_PORT: "3000"
  DOMAIN_NAME: node.example.com

1. Now, you can run the command odo deploy to deploy the application to the cluster:

警告

You may run into an unauthorized: image error as the image may not be covered by Rancher Desktop’s allowed images list. To resolve the error, please add the necessary image in Preferences > Container Engine > Allowed Images and hit apply to update allowed images immediately.

Sample Output

$ odo deploy
  __
 /  \__     Running the application in Deploy mode using my-node-app Devfile
 \__/  \    Namespace: odo-dev
 /  \__/    odo version: v3.13.0
 \__/
↪ Building & Pushing Image: docker.io/arjsin/nodejs-odo-example
 •  Building image locally  ...
[+] Building 2.7s (9/9) FINISHED                                                
 => [internal] load build definition from Dockerfile                       0.0s
 => => transferring dockerfile: 405B                                       0.0s
 => [internal] load .dockerignore                                          0.0s
 => => transferring context: 364B                                          0.0s
 => [internal] load metadata for registry.suse.com/bci/nodejs:16           2.2s
 => [1/4] FROM registry.suse.com/bci/nodejs:16@sha256:dda0e616a0fcb3dc589  0.0s
 => [internal] load build context                                          0.0s
 => => transferring context: 5.14kB                                        0.0s
 => CACHED [2/4] COPY package*.json ./                                     0.0s
 => CACHED [3/4] RUN npm install --production                              0.0s
 => [4/4] COPY . /opt/app-root/src                                         0.0s
 => exporting to image                                                     0.4s
 => => exporting layers                                                    0.4s
 => => writing image sha256:c6d3ed7d9fb4736d3c4e95b54054533f79d64d3a01e65  0.0s
 => => naming to docker.io/arjsin/nodejs-odo-example                       0.0s
 ✓  Building image locally [3s]
 •  Pushing image to container registry  ...
Using default tag: latest
The push refers to repository [docker.io/arjsin/nodejs-odo-example]
20658d9b13ba: Pushed 
7b1ee26c3aea: Pushed 
067890bef08d: Pushed 
d08e96dfc7bc: Pushed 
174c0e293bd0: Pushed 
latest: digest: sha256:ca598fc0c5278e8d00cba41e14914f1d3f7a3561bd4a324f2ffcd33b166135ad size: 1368
 ✓  Pushing image to container registry [30s]
↪ Deploying Kubernetes Component: my-node-app
 ✓  Creating resource Deployment/my-node-app 
↪ Deploying Kubernetes Component: my-node-app
 ✓  Creating resource Service/my-node-app 
↪ Deploying Kubernetes Component: my-node-app
 ✓  Creating resource Ingress/my-node-app 
Your Devfile has been successfully deployed

Steps: odo describe component

Now, the command odo describe component can be used to view information from the Devfile such as Kubernetes components, ingresses, and the URL to access the application:

odo describe component

Sample Output

$ odo describe component
Name: my-nodejs-app
Display Name: Node.js Runtime
Project Type: Node.js
Language: JavaScript
Version: 2.2.0
Description: Node.js 18 application
Tags: Node.js, Express, ubi8
Running in: None
Supported odo features:
 •  Dev: true
 •  Deploy: false
 •  Debug: true
Commands:
 •  install
      Type: exec
      Group: build
      Command Line: "npm install"
      Component: runtime
      Component Type: container
 •  run
      Type: exec
      Group: run
      Command Line: "npm start"
      Component: runtime
      Component Type: container
 •  debug
      Type: exec
      Group: debug
      Command Line: "npm run debug"
      Component: runtime
      Component Type: container
 •  test
      Type: exec
      Group: test
      Command Line: "npm test"
      Component: runtime
      Component Type: container
Container components:
 •  runtime
    Source Mapping: /projects

Steps: odo delete component

After you have completed testing, you can free the resources used by odo by using the command odo delete component:

odo delete component

Sample Output

$ odo delete component
Searching resources to delete, please wait...
This will delete "my-node-app" from the namespace "odo-dev".
 •  The following resources will get deleted from cluster:
 •      - Deployment: my-node-app
 •      - Service: my-node-app
 •      - Ingress: my-node-app
? Are you sure you want to delete "my-node-app" and all its resources? Yes
 ✓  Deleting resources from cluster [52ms]
The component "my-node-app" is successfully deleted from namespace "odo-dev"