This\u00a0lab is designed to give you an idea of what Knative<\/a> does, how you use Knative API to deploy applications and how it relates to Kubernetes<\/a>.<\/p>\n\n\n\n
Assumptions and Prerequisites<\/h2>\n\n\n\n- Basic hands-on experience with Kubernetes.<\/li>
- Up and Running Kubernetes Cluster (e.g GKE, AKS, EKS,..) v1.15 or newer<\/li>
- You have kubectl<\/a> \u00a0installed in your local machine.<\/li>
- You have Go<\/a> installed in your local machine<\/li><\/ul>\n\n\n\n
Objectives: what you will learn ?<\/h2>\n\n\n\n- \u2705 How to install Knative on a Kubernetes cluster<\/li>
- \u2705 Deploy a web application from source to Knative<\/li>
- \u2705 Autoscale applications from 0-to-1, 1-to-N, and back to 0<\/li>
- \u2705 Knative Serving API types and the relationship between them<\/li>
- \u2705 Roll out new versions (blue\/green deployments) with Knative Serving API<\/li><\/ol>\n\n\n\n
Before starting<\/h2>\n\n\n\n
Knative is installed as a set of custom APIs and controllers on Kubernetes. You can easily create managed Kubernetes cluster with Google Kubernetes Engine (GKE)<\/a> also with Amazon Elastic Kubernetes Service<\/a> and have operate the cluster and autoscaling for you.
In this lab, in order of deploying serverless Services on Kubernetes using Knative, we’ll be using Azure AKS<\/a> -Azure’s Managed Kubernetes Service- as our K8S backend cluster.<\/p>\n\n\n\nTo create an Azure AKS cluster, preferably you use an Infrastructure as Code tool like Terraform. Although cluster creation isn\u2019t covered by this lab, however you can follow my IaC lab to deploy AKS with Terraform <\/a> <\/p>\n\n\n\n![\"build](\"https:\/\/aymen-segni.com\/wp-content\/uploads\/2020\/07\/Screenshot-2020-07-21-at-12.47.12-1024x475.png\")
Azure AKS K8S Cluster<\/figcaption><\/figure>\n\n\n\nConnect to cluster using kubectl<\/h4>\n\n\n\n
To configure kubectl<\/code> to connect to your Kubernetes cluster, use the az aks get-credentials<\/a> command. Following example gets credentials for the AKS cluster named myAKSCluster<\/em> in the myResourceGroup<\/em>:<\/p>\n\n\n\n\n\naz aks get-credentials --resource-group myResourceGroup --name myAKSCluster<\/code><\/pre>\n<\/code><\/pre>\n\n\n\nTo verify the connection to your cluster, run the kubectl get nodes<\/a> command to return a list of the cluster nodes. <\/p>\n\n\n\nNow you have a fully-provisioned Kubernetes cluster running in Azure, and you’re ready to install Knative on it!<\/p>\n\n\n\n
1- Introduction to Knative<\/h2>\n\n\n\n
Knative (pronounced kay-nay-tiv) extends Kubernetes<\/a> to provide a set of middleware components that are essential to build modern, source-centric, and container-based applications that can run anywhere: on premises, in the cloud, or even in a third-party data center.<\/p>\n\n\n\nKnative makes it possible to:<\/p>\n\n\n\n
- Deploy and serve<\/strong> applications with a higher-level and easier to understand API. These applications automatically scale from zero-to-N, and back to zero, based on requests.<\/li>
- Build<\/strong> and package your application code inside the cluster.<\/li>
- Deliver events<\/strong> to your application. You can define custom event sources and declare subscriptions between event buses and your applications.<\/li><\/ol>\n\n\n\n
Developers on Knative can use familiar idioms, languages, and frameworks to deploy functions, applications, or containers workloads.
This is why, Knative provides developer experiences similar to serverless <\/strong>platforms.<\/strong> You can read the documentation at <\/a>https:\/\/knative.dev\/docs\/<\/a>.<\/p>\n\n\n\nKnative is still Kubernetes!<\/h4>\n\n\n\n
If you deployed applications with Kubernetes before, Knative will feel familiar to you. You will still write YAML manifest files and deploy container images on a Kubernetes cluster.<\/p>\n\n\n\n
2- Who is Knative for?<\/h2>\n\n\n\nKnative APIs<\/h4>\n\n\n\n
Kubernetes offers a feature called Custom Resource Definitions (CRDs). With CRDs, third party Kubernetes controllers like Istio or Knative can install more APIs into Kubernetes.<\/p>\n\n\n\n
Knative installs of three families of custom resource APIs:<\/p>\n\n\n\n
- Knative Serving: <\/strong>Set of APIs that help you host applications that serve traffic. Provides features like custom routing and autoscaling.<\/li>
- Knative Eventing: <\/strong>Set of APIs that let you declare event sources and event delivery to your applications. (Not covered in this codelab due to time constraints.)<\/em><\/li><\/ul>\n\n\n\n
Together, Knative Serving and Eventing APIs provide a common set of middleware for Kubernetes applications. We will use these APIs to run build and run applications.<\/p>\n\n\n\n
Is Knative for me?<\/h4>\n\n\n\n![\"Deploying](\"https:\/\/aymen-segni.com\/wp-content\/uploads\/2020\/07\/Screenshot-2020-07-21-at-13.41.05-1024x537.png\")
Knative Audiences (Knative Doc)<\/figcaption><\/figure>\n\n\n\nKnative serves two main audiences:<\/p>\n\n\n\n
1. I want to deploy on Kubernetes easier:<\/strong><\/p>\n\n\n\n- Knative makes it easy to declare an application that auto-scales, without worrying about container parameters like CPU, memory, or concerns like activation\/deactivation.<\/li>
- You can go from a code in a repo to app running on Knative very easily.<\/li><\/ul>\n\n\n\n
2. I want to build my own PaaS\/FaaS on Kubernetes:<\/strong><\/p>\n\n\n\n- You can use these Knative components and APIs to build a custom deployment platform that looks like Heroku or AWS Lambda at your company.<\/li>
- Knative Serving has many valuable “plumbing” components like the autoscaler, request based activation, telemetry.<\/li>
- Knative Build lets you declare transformations on the source code, like converting functions to apps, and apps to containers.<\/li>
- You don’t have to reinvent the wheel, can reuse plumbing components offered by Knative.<\/li><\/ul>\n\n\n\n
Knative principles<\/h4>\n\n\n\n- Knative is native to Kubernetes (APIs are hosted on Kubernetes, deployment unit is container images)<\/li>
- You can install\/use parts of Knative independently (e.g. only Knative Build, to do in-cluster builds)<\/li>
- Knative components are pluggable (e.g. don’t like the autoscaler? write your own)<\/li><\/ul>\n\n\n\n
3- Installing Knative<\/h2>\n\n\n\n
This guide walks you through the installation of the latest version of Knative. Knative has two components, which can be installed and used independently or together. <\/p>\n\n\n\n
- Serving<\/strong><\/a>
stable @ v0.9<\/code> <\/li>- Eventing<\/strong><\/a>
stable @ v0.16<\/code> <\/li><\/ul>\n\n\n\nKnative also has an Observability plugin<\/strong><\/a> deprecated @ v0.14<\/code> which provides standard tooling that can be used to get visibility into the health of the software running on Knative.<\/p>\n\n\n\nInstalling the Serving component<\/h4>\n\n\n\n
\n
# install the CRDs
kubectl apply –filename \\ https:\/\/github.com\/knative\/serving\/releases\/download\/v0.16.0\/serving-crds.yaml
# install the core components of Serving
kubectl apply –filename \\ https:\/\/github.com\/knative\/serving\/releases\/download\/v0.16.0\/serving-core.yaml
<\/code><\/pre>\n<\/p>\n\n\n\nPick a networking layer: Istio<\/a><\/h4>\n\n\n\n1- Installing Istioctl<\/strong><\/p>\n\n\n\n\n
curl -sL https:\/\/istio.io\/downloadIstioctl | sh –
export PATH=$PATH:$HOME\/.istioctl\/bin
<\/code><\/pre>\n<\/p>\n\n\n\n2- Choosing an Istio installation<\/strong><\/p>\n\n\n\nWhen you install Istio, there are a few options depending on your goals. For a basic Istio installation suitable for most Knative use cases, follow the Installing Istio without sidecar injection<\/a> instructions. If you’re familiar with Istio and know what kind of installation you want, read through the options and choose the installation that suits your needs here: https:\/\/knative.dev\/docs\/install\/installing-istio\/<\/a><\/p>\n\n\n\n
Objectives: what you will learn ?<\/h2>\n\n\n\n- \u2705 How to install Knative on a Kubernetes cluster<\/li>
- \u2705 Deploy a web application from source to Knative<\/li>
- \u2705 Autoscale applications from 0-to-1, 1-to-N, and back to 0<\/li>
- \u2705 Knative Serving API types and the relationship between them<\/li>
- \u2705 Roll out new versions (blue\/green deployments) with Knative Serving API<\/li><\/ol>\n\n\n\n
Before starting<\/h2>\n\n\n\n
Knative is installed as a set of custom APIs and controllers on Kubernetes. You can easily create managed Kubernetes cluster with Google Kubernetes Engine (GKE)<\/a> also with Amazon Elastic Kubernetes Service<\/a> and have operate the cluster and autoscaling for you.
In this lab, in order of deploying serverless Services on Kubernetes using Knative, we’ll be using Azure AKS<\/a> -Azure’s Managed Kubernetes Service- as our K8S backend cluster.<\/p>\n\n\n\nTo create an Azure AKS cluster, preferably you use an Infrastructure as Code tool like Terraform. Although cluster creation isn\u2019t covered by this lab, however you can follow my IaC lab to deploy AKS with Terraform <\/a> <\/p>\n\n\n\nAzure AKS K8S Cluster<\/figcaption><\/figure>\n\n\n\nConnect to cluster using kubectl<\/h4>\n\n\n\n
To configure kubectl<\/code> to connect to your Kubernetes cluster, use the az aks get-credentials<\/a> command. Following example gets credentials for the AKS cluster named myAKSCluster<\/em> in the myResourceGroup<\/em>:<\/p>\n\n\n\n\n\naz aks get-credentials --resource-group myResourceGroup --name myAKSCluster<\/code><\/pre>\n<\/code><\/pre>\n\n\n\nTo verify the connection to your cluster, run the kubectl get nodes<\/a> command to return a list of the cluster nodes. <\/p>\n\n\n\nNow you have a fully-provisioned Kubernetes cluster running in Azure, and you’re ready to install Knative on it!<\/p>\n\n\n\n
1- Introduction to Knative<\/h2>\n\n\n\n
Knative (pronounced kay-nay-tiv) extends Kubernetes<\/a> to provide a set of middleware components that are essential to build modern, source-centric, and container-based applications that can run anywhere: on premises, in the cloud, or even in a third-party data center.<\/p>\n\n\n\nKnative makes it possible to:<\/p>\n\n\n\n
- Deploy and serve<\/strong> applications with a higher-level and easier to understand API. These applications automatically scale from zero-to-N, and back to zero, based on requests.<\/li>
- Build<\/strong> and package your application code inside the cluster.<\/li>
- Deliver events<\/strong> to your application. You can define custom event sources and declare subscriptions between event buses and your applications.<\/li><\/ol>\n\n\n\n
Developers on Knative can use familiar idioms, languages, and frameworks to deploy functions, applications, or containers workloads.
This is why, Knative provides developer experiences similar to serverless <\/strong>platforms.<\/strong> You can read the documentation at <\/a>https:\/\/knative.dev\/docs\/<\/a>.<\/p>\n\n\n\nKnative is still Kubernetes!<\/h4>\n\n\n\n
If you deployed applications with Kubernetes before, Knative will feel familiar to you. You will still write YAML manifest files and deploy container images on a Kubernetes cluster.<\/p>\n\n\n\n
2- Who is Knative for?<\/h2>\n\n\n\nKnative APIs<\/h4>\n\n\n\n
Kubernetes offers a feature called Custom Resource Definitions (CRDs). With CRDs, third party Kubernetes controllers like Istio or Knative can install more APIs into Kubernetes.<\/p>\n\n\n\n
Knative installs of three families of custom resource APIs:<\/p>\n\n\n\n
- Knative Serving: <\/strong>Set of APIs that help you host applications that serve traffic. Provides features like custom routing and autoscaling.<\/li>
- Knative Eventing: <\/strong>Set of APIs that let you declare event sources and event delivery to your applications. (Not covered in this codelab due to time constraints.)<\/em><\/li><\/ul>\n\n\n\n
Together, Knative Serving and Eventing APIs provide a common set of middleware for Kubernetes applications. We will use these APIs to run build and run applications.<\/p>\n\n\n\n
Is Knative for me?<\/h4>\n\n\n\nKnative Audiences (Knative Doc)<\/figcaption><\/figure>\n\n\n\nKnative serves two main audiences:<\/p>\n\n\n\n
1. I want to deploy on Kubernetes easier:<\/strong><\/p>\n\n\n\n- Knative makes it easy to declare an application that auto-scales, without worrying about container parameters like CPU, memory, or concerns like activation\/deactivation.<\/li>
- You can go from a code in a repo to app running on Knative very easily.<\/li><\/ul>\n\n\n\n
2. I want to build my own PaaS\/FaaS on Kubernetes:<\/strong><\/p>\n\n\n\n- You can use these Knative components and APIs to build a custom deployment platform that looks like Heroku or AWS Lambda at your company.<\/li>
- Knative Serving has many valuable “plumbing” components like the autoscaler, request based activation, telemetry.<\/li>
- Knative Build lets you declare transformations on the source code, like converting functions to apps, and apps to containers.<\/li>
- You don’t have to reinvent the wheel, can reuse plumbing components offered by Knative.<\/li><\/ul>\n\n\n\n
Knative principles<\/h4>\n\n\n\n- Knative is native to Kubernetes (APIs are hosted on Kubernetes, deployment unit is container images)<\/li>
- You can install\/use parts of Knative independently (e.g. only Knative Build, to do in-cluster builds)<\/li>
- Knative components are pluggable (e.g. don’t like the autoscaler? write your own)<\/li><\/ul>\n\n\n\n
3- Installing Knative<\/h2>\n\n\n\n
This guide walks you through the installation of the latest version of Knative. Knative has two components, which can be installed and used independently or together. <\/p>\n\n\n\n
- Serving<\/strong><\/a>
stable @ v0.9<\/code> <\/li>- Eventing<\/strong><\/a>
stable @ v0.16<\/code> <\/li><\/ul>\n\n\n\nKnative also has an Observability plugin<\/strong><\/a> deprecated @ v0.14<\/code> which provides standard tooling that can be used to get visibility into the health of the software running on Knative.<\/p>\n\n\n\nInstalling the Serving component<\/h4>\n\n\n\n
\n
# install the CRDs
kubectl apply –filename \\ https:\/\/github.com\/knative\/serving\/releases\/download\/v0.16.0\/serving-crds.yaml
# install the core components of Serving
kubectl apply –filename \\ https:\/\/github.com\/knative\/serving\/releases\/download\/v0.16.0\/serving-core.yaml
<\/code><\/pre>\n<\/p>\n\n\n\nPick a networking layer: Istio<\/a><\/h4>\n\n\n\n1- Installing Istioctl<\/strong><\/p>\n\n\n\n\n
curl -sL https:\/\/istio.io\/downloadIstioctl | sh –
export PATH=$PATH:$HOME\/.istioctl\/bin
<\/code><\/pre>\n<\/p>\n\n\n\n2- Choosing an Istio installation<\/strong><\/p>\n\n\n\nWhen you install Istio, there are a few options depending on your goals. For a basic Istio installation suitable for most Knative use cases, follow the Installing Istio without sidecar injection<\/a> instructions. If you’re familiar with Istio and know what kind of installation you want, read through the options and choose the installation that suits your needs here: https:\/\/knative.dev\/docs\/install\/installing-istio\/<\/a><\/p>\n\n\n\n
Before starting<\/h2>\n\n\n\n
Knative is installed as a set of custom APIs and controllers on Kubernetes. You can easily create managed Kubernetes cluster with Google Kubernetes Engine (GKE)<\/a> also with Amazon Elastic Kubernetes Service<\/a> and have operate the cluster and autoscaling for you. To create an Azure AKS cluster, preferably you use an Infrastructure as Code tool like Terraform. Although cluster creation isn\u2019t covered by this lab, however you can follow my IaC lab to deploy AKS with Terraform <\/a> <\/p>\n\n\n\n To configure To verify the connection to your cluster, run the kubectl get nodes<\/a> command to return a list of the cluster nodes. <\/p>\n\n\n\n Now you have a fully-provisioned Kubernetes cluster running in Azure, and you’re ready to install Knative on it!<\/p>\n\n\n\n Knative (pronounced kay-nay-tiv) extends Kubernetes<\/a> to provide a set of middleware components that are essential to build modern, source-centric, and container-based applications that can run anywhere: on premises, in the cloud, or even in a third-party data center.<\/p>\n\n\n\n Knative makes it possible to:<\/p>\n\n\n\n Developers on Knative can use familiar idioms, languages, and frameworks to deploy functions, applications, or containers workloads. If you deployed applications with Kubernetes before, Knative will feel familiar to you. You will still write YAML manifest files and deploy container images on a Kubernetes cluster.<\/p>\n\n\n\n Kubernetes offers a feature called Custom Resource Definitions (CRDs). With CRDs, third party Kubernetes controllers like Istio or Knative can install more APIs into Kubernetes.<\/p>\n\n\n\n Knative installs of three families of custom resource APIs:<\/p>\n\n\n\n Together, Knative Serving and Eventing APIs provide a common set of middleware for Kubernetes applications. We will use these APIs to run build and run applications.<\/p>\n\n\n\n Knative serves two main audiences:<\/p>\n\n\n\n 1. I want to deploy on Kubernetes easier:<\/strong><\/p>\n\n\n\n 2. I want to build my own PaaS\/FaaS on Kubernetes:<\/strong><\/p>\n\n\n\n This guide walks you through the installation of the latest version of Knative. Knative has two components, which can be installed and used independently or together. <\/p>\n\n\n\n Knative also has an Observability plugin<\/strong><\/a> \n 1- Installing Istioctl<\/strong><\/p>\n\n\n\n \n 2- Choosing an Istio installation<\/strong><\/p>\n\n\n\n When you install Istio, there are a few options depending on your goals. For a basic Istio installation suitable for most Knative use cases, follow the Installing Istio without sidecar injection<\/a> instructions. If you’re familiar with Istio and know what kind of installation you want, read through the options and choose the installation that suits your needs here: https:\/\/knative.dev\/docs\/install\/installing-istio\/<\/a><\/p>\n\n\n\n
In this lab, in order of deploying serverless Services on Kubernetes using Knative, we’ll be using Azure AKS<\/a> -Azure’s Managed Kubernetes Service- as our K8S backend cluster.<\/p>\n\n\n\nConnect to cluster using kubectl<\/h4>\n\n\n\n
kubectl<\/code> to connect to your Kubernetes cluster, use the az aks get-credentials<\/a> command. Following example gets credentials for the AKS cluster named myAKSCluster<\/em> in the myResourceGroup<\/em>:<\/p>\n\n\n\n\n\naz aks get-credentials --resource-group myResourceGroup --name myAKSCluster<\/code><\/pre>\n<\/code><\/pre>\n\n\n\n1- Introduction to Knative<\/h2>\n\n\n\n
This is why, Knative provides developer experiences similar to serverless <\/strong>platforms.<\/strong> You can read the documentation at <\/a>https:\/\/knative.dev\/docs\/<\/a>.<\/p>\n\n\n\nKnative is still Kubernetes!<\/h4>\n\n\n\n
2- Who is Knative for?<\/h2>\n\n\n\n
Knative APIs<\/h4>\n\n\n\n
Is Knative for me?<\/h4>\n\n\n\n
Knative principles<\/h4>\n\n\n\n
3- Installing Knative<\/h2>\n\n\n\n
stable @ v0.9<\/code> <\/li>stable @ v0.16<\/code> <\/li><\/ul>\n\n\n\ndeprecated @ v0.14<\/code> which provides standard tooling that can be used to get visibility into the health of the software running on Knative.<\/p>\n\n\n\nInstalling the Serving component<\/h4>\n\n\n\n
# install the CRDs
kubectl apply –filename \\ https:\/\/github.com\/knative\/serving\/releases\/download\/v0.16.0\/serving-crds.yaml
# install the core components of Serving
kubectl apply –filename \\ https:\/\/github.com\/knative\/serving\/releases\/download\/v0.16.0\/serving-core.yaml
<\/code><\/pre>\n<\/p>\n\n\n\nPick a networking layer: Istio<\/a><\/h4>\n\n\n\n
curl -sL https:\/\/istio.io\/downloadIstioctl | sh –
export PATH=$PATH:$HOME\/.istioctl\/bin
<\/code><\/pre>\n<\/p>\n\n\n\n
![\"Deploying](\"https:\/\/aymen-segni.com\/wp-content\/uploads\/2020\/07\/Screenshot-2020-07-21-at-15.42.24.png\")
![\"\"](\"https:\/\/aymen-segni.com\/wp-content\/uploads\/2020\/07\/Screenshot-2020-07-21-at-00.16.01-746x1024.png\")
![\"\"](\"https:\/\/aymen-segni.com\/wp-content\/uploads\/2020\/07\/879cbeae5e35bc6b-1024x339.png\")