Dispatch

Dispatch is a framework for deploying and managing serverless style applications. The intent is a framework which enables developers to build applications which are defined by functions which handle business logic and services which provide all other functionality:

State (Databases)
Messaging/Eventing (Queues)
Ingress (Api-Gateways)
Etc.

Our goal is to provide a substrate which can be built upon and extended to serve as a framework for serverless applications. Additionally, the framework must provide tools and features which aid the developer in building, debugging and maintaining their serverless application.

Architecture

The diagram below illustrates the different components which make up the Dispatch project:

Quickstart

Assumptions:

Minikube is installed. If not, simply download and install minikube (See minikube).
Kubectl installed and configured for minikube.
Running on MacOS or Linux

Start Minikube and initialize Helm

For MacOS

# Start minikube (if not already started)
$ minikube start --vm-driver=hyperkit --bootstrapper=kubeadm --disk-size=50g --memory=6144 --kubernetes-version=v1.8.1
# Install and initialize helm (if not already installed)
$ brew install kubernetes-helm
$ helm init

For Linux

$ minikube start --vm-driver=none --bootstrapper=kubeadm --kubernetes-version=v1.8.1
# Install helm and initialize helm
# Check https://github.com/kubernetes/helm/releases for latest version
$ curl -Lo helm-linux-amd64.tar.gz https://storage.googleapis.com/kubernetes-helm/helm-v2.8.0-linux-amd64.tar.gz && tar -zxvf helm-linux-amd64.tar.gz && mv linux-amd64/helm /usr/local/bin/helm
$ helm init

Download Dispatch CLI

Get the dispatch command, make it executable, and put it in your path:

For MacOS

$ curl -OL https://github.com/vmware/dispatch/releases/download/v0.1.6/dispatch-darwin
$ chmod +x dispatch-darwin
$ mv dispatch-darwin /usr/local/bin/dispatch

For Linux

$ curl -OL https://github.com/vmware/dispatch/releases/download/v0.1.6/dispatch-linux
$ chmod +x dispatch-linux
$ mv dispatch-linux /usr/local/bin/dispatch

Configure and install Dispatch:

Fetch the IP address of minikube as this will be used the host for dispatch services.

export DISPATCH_HOST=$(minikube ip)

Configure the installation (note: you must substitute the IP address where $DISPATCH_HOST is specified in the below config.yaml):

$ cat << EOF > config.yaml
apiGateway:
  host: $DISPATCH_HOST
dispatch:
  host: $DISPATCH_HOST
  debug: true
  skipAuth: true
EOF

$ dispatch install --file config.yaml
...
Config file written to: $HOME/.dispatch/config.json

Your dispatch config file $HOME/.dispatch/config.json will be generated and have the following:-

cat $HOME/.dispatch/config.json
{
    "host": "<DISPATCH_HOST>",
    "port": <port>,
    "organization": "dispatch",
    "cookie": "",
    "insecure": false,
    "skipauth": true,
    "Json": false,
    "api-https-port": <API_HTTPS_PORT>,
    "api-http-port": <API_HTTP_PORT>
}

Change the "insecure": false to "insecure": true to skip the validation of dispatch server certificates when using the dispatch CLI. Note:- This is not recommended for production environments.

At this point, the environment is up and working. Let's seed the service with some images and functions. In order to get the examples, you will need to clone the repository (if you haven't already):

$ cd examples/
$ dispatch create --file seed.yaml
$ dispatch get images
   NAME   |                    URL                           |  BASEIMAGE   |   STATUS    |         CREATED DATE
------------------------------------------------------------------------------------------------------------------------
  nodejs6 | vmware/dispatch-openfaas-nodejs6-base:0.0.2-dev1 | nodejs6-base | READY       | Wed Dec  6 14:28:30 PST 2017
  python3 | vmware/dispatch-openfaas-python-base:0.0.4-dev1  | python3-base | INITIALIZED | Wed Dec  6 14:28:30 PST 2017

$ dispatch get functions
    NAME   |  IMAGE  | STATUS |         CREATED DATE
------------------------------------------------------------
  hello-js | nodejs6 | READY  | Wed Dec  6 14:29:05 PST 2017
  hello-py | python3 | READY  | Wed Dec  6 14:28:52 PST 2017

Execute a function:

$ dispatch exec hello-py --input '{"name": "Jon", "place": "Winterfell"}' --wait
{
    "blocking": true,
    "executedTime": 1515624222,
    "finishedTime": 1515624222,
    "functionId": "5138d918-e78f-41d6-aece-769addd3eed7",
    "functionName": "hello-py",
    "input": {
        "name": "Jon",
        "place": "Winterfell"
    },
    "logs": null,
    "name": "b5b3c1f5-fa8a-4b38-b7d1-475c44b76114",
    "output": {
        "myField": "Hello, Jon from Winterfell"
    },
    "reason": null,
    "secrets": [],
    "status": "READY"
}

Add an API endpoint:

$ dispatch create api --https-only --method POST --path /hello post-hello hello-py

Find the port for the api-gateway service (we are using the NodePort service type):

$ kubectl -n kong get service api-gateway-kongproxy
NAME                    CLUSTER-IP     EXTERNAL-IP   PORT(S)                      AGE
api-gateway-kongproxy   10.107.109.1   <nodes>       80:31788/TCP,443:32611/TCP   19m

We are looking at the port associated with https/443 => 32611

$ curl -k "https://$DISPATCH_HOST:32611/hello" -H "Content-Type: application/json" -d '{"name": "Jon", "place": "Winterfell"}'
{"myField":"Hello, Jon from Winterfell"}

Install Dispatch UI

helm install dispatch/ui --namespace dispatch --name ui --debug

Now open up a browser to: https://$DISPATCH_HOST/ui/

Now go build something!

Standard Installation

Prerequisites

Dispatch depends on Kubernetes as its deployment infrastructure. Any "standard" kubernetes should be supported. Development is largely done on minikube as it allows for easy local deployment. This guide will focus on two deployment models, minikube and vanilla hosted kubernetes 1.7+.

Kubernetes

A Kubernetes 1.7+ cluster with PersistentVolume(PV) provisioner support is required for installing the Dispatch project.

Minikube

Installing minikube is easy. The following installs the latest minikube on a mac. See the official minikube repository for more details:

$ brew cask install minikube
==> Satisfying dependencies
All Formula dependencies satisfied.
==> Downloading https://storage.googleapis.com/minikube/releases/v0.24.1/minikube-darwin-amd64
######################################################################## 100.0%
==> Verifying checksum for Cask minikube
==> Installing Cask minikube
==> Linking Binary 'minikube-darwin-amd64' to '/usr/local/bin/minikube'.
🍺  minikube was successfully installed!

Install the VM driver of your choice. We recommend hyperkit:

$ curl -LO https://storage.googleapis.com/minikube/releases/latest/docker-machine-driver-hyperkit && chmod +x docker-machine-driver-hyperkit && sudo mv docker-machine-driver-hyperkit /usr/local/bin/ && sudo chown root:wheel /usr/local/bin/docker-machine-driver-hyperkit && sudo chmod u+s /usr/local/bin/docker-machine-driver-hyperkit

Create a kubernetes cluster:

$ minikube start --vm-driver=hyperkit --bootstrapper=kubeadm --disk-size=50g --memory=4096 --kubernetes-version=v1.8.1
Starting local Kubernetes v1.8.0 cluster...
Starting VM...
Downloading Minikube ISO
 140.01 MB / 140.01 MB [============================================] 100.00% 0s
Getting VM IP address...
Moving files into cluster...
Downloading kubeadm v1.8.0
Downloading kubelet v1.8.0
Finished Downloading kubelet v1.8.0
Finished Downloading kubeadm v1.8.0
Setting up certs...
Connecting to cluster...
Setting up kubeconfig...
Starting cluster components...
Kubectl is now configured to use the cluster.
Loading cached images from config file.

Verify installation:

$ kubectl get pods --all-namespaces
NAMESPACE     NAME                          READY     STATUS    RESTARTS   AGE
kube-system   kube-addon-manager-minikube   1/1       Running   0          54s
kube-system   kube-dns-545bc4bfd4-mjljc     3/3       Running   0          43s
kube-system   kube-proxy-nmzhd              1/1       Running   0          43s
kube-system   kubernetes-dashboard-5fllx    1/1       Running   2          41s
kube-system   storage-provisioner           1/1       Running   0          42s

Hosted Kubernetes

There are a variety of methods for installing kubernetes in a hosted environment (including a private datacenter). This is beyond the scope of this guide. However, the dispatch charts depend on RBAC being enabled on the cluster. Check the documentation of your Kubernetes deployer on how to enable RBAC authorization.

Helm

Helm is the package manager for Kubernetes. Dispatch as well as many dependencies are installed and managed via helm charts. Before anything can be installed, helm must be setup.

RBAC and Helm

Recent versions of Kubernetes have introduced roles and service accounts. Depending on how your Kubernetes cluster is configured, one or more of the following may be required:

Add the cluster-admin clusterrole (required for Kubernetes on OpenStack - VIOK):

$ kubectl create clusterrole cluster-admin --verb=get,list,watch,create,delete,update,patch --resource=deployments,services,secrets
$ kubectl create clusterrolebinding tiller-cluster-admin --clusterrole=cluster-admin --serviceaccount=kube-system:default

Note: some kubernetes deployments come with cluster-admin already, if so, you could skip the kubectl create clusterrole command

Add the tiller service account (required for clusters created via Kops - AWS):

kubectl -n kube-system create serviceaccount tiller
kubectl create clusterrolebinding tiller --clusterrole cluster-admin --serviceaccount=kube-system:tiller
helm init --service-account tiller

Note: Although required for clusters created with Kops, creating a specific service account for tiller should be OK, and even encouraged, for all deployments.

Download Helm and install tiller:

$ brew install kubernetes-helm
# If not using the tiller service account, simply run `helm init`
$ helm init --service-account tiller
$HELM_HOME has been configured at /Users/bjung/.helm.

Tiller (the Helm server-side component) has been installed into your Kubernetes Cluster.
Happy Helming!

Set a Few Environment Variables

Define the following environment variables. The actual values can be whatever you like:

export DISPATCH_HOST=dispatch.local
export DISPATCH_NAMESPACE=dispatch
export DISPATCH_OAUTH_CLIENT_ID = <oauth-client-id>
export DISPATCH_OAUTH_CLIENT_SECRET = <oauth-client-secret>
export DISPATCH_OAUTH_COOKIE_SECRET = <oauth-cookie-secret>

# In the case of dockerhub, just use your docker username (i.e.
# DOCKER_REGISTRY=berndtj)
export DOCKER_REGISTRY=vmware/dispatch

Please see How to Create OAuth Client App to learn to how to generate <oauth-client-id>, <oauth-client-secret> and <oauth-cookie-secret> (note: currently GitHub is the only supported provider)

Configure Image Registry

Dispatch pulls and pushes images as part of the image manager component. In order to do so, image registry credentials must be configured:

$ kubectl create secret docker-registry regsecret --docker-server=<your-registry-server> --docker-username=<your-name> --docker-password=<your-pword> --docker-email=<your-email>

Docker hub example:

$ kubectl create secret docker-registry regsecret --docker-server='https://index.docker.io/v1/' --docker-username=dockerhub-user --docker-password='...' --docker-email=dockerhub-user@gmail.com

Import self-signed TLS certificates into Kubernetes secret

To be able to securely connect to Dispatch, we need to set up a TLS certificate.

$ ./scripts/make-ssl-crt.sh $DISPATCH_NAMESPACE $DISPATCH_HOST

With the above command, we create a self-signed certificates named dispatch-tls, and api-dispatch-tls, and then import it into kubernetes secret store.

Note this is only required ONCE per a kubernetes cluster.

Install Ingress Controller

A nginx ingress controller is required for Dispatch, please install it with (this will be installed into the kube-system namespace).

For minikube:

$ helm install ./charts/nginx-ingress --namespace=kube-system --name=ingress --set=controller.service.type=NodePort --wait

For hosted kubernetes:

$ helm install ./charts/nginx-ingress --namespace=kube-system --name=ingress --wait

Get IP address to ingress controller by:

For minikube:

$ minikube ip

For hosted kubernetes:

$ kubectl describe service ingress-nginx-ingress-controller --namespace=kube-system

You should find the public IP from the LoadBalancer section,

Edit etc/hosts and add/edit a record for this Dispatch deployment:

$ cat /etc/hosts
##
# Host Database
#
# localhost is used to configure the loopback interface
# when the system is booting.  Do not change this entry.
##
127.0.0.1	localhost
255.255.255.255	broadcasthost
::1             localhost
192.168.64.7	dispatch.local

Install FaaS (OpenFaaS)

The framework is architected to support multiple FaaS implementations. Presently OpenFaaS is the preferred FaaS:

$ helm install --namespace=openfaas --name=openfaas --set=exposeServices=false ./charts/openfaas --wait

Install Api-gateway (Kong)

For minikube:

helm install --namespace=kong --name=api-gateway --set services.proxyService.type=NodePort ./charts/kong --wait

For hosted kubernetes:

helm install --namespace=kong --name=api-gateway ./charts/kong --wait

Building and Deploying Dispatch

Now that all of the setup is done, the only thing left is to build and deploy. Ideally, as long as the cluster is up, you are done with setup.

Building Images

If you're using the newly built images in minikube locally, you can set your docker client to use the minikube docker daemon:

eval $(minikube docker-env)

By default, the images are prefixed with vmware (e.g. vmware/dispatch-event-driver). If you need to use a different registry, set the DOCKER_REGISTRY environment variable:

$ echo $DOCKER_REGISTRY
dockerhub-user

If you need to push the new images, your docker client must be logged into the registry:

docker login $DOCKER_REGISTRY

NOTE: if using docker hub, do not include the registry as an argument (i.e. docker login)

To build the images:

make images

To build and push the images:

PUSH_IMAGES=1 make images

The result should be 7 images:

$ docker images | grep $(cat values.yaml | grep tag | cut -d ':' -f 2)
berndtj/dispatch-event-driver                                                                dev-1511831075      285ebca2a1a2        24 minutes ago      106MB
berndtj/dispatch-event-manager                                                               dev-1511831075      537108e4fe2b        24 minutes ago      61.2MB
berndtj/dispatch-api-manager                                                                 dev-1511831075      c735cc5539fe        24 minutes ago      58.8MB
berndtj/dispatch-secret-store                                                                dev-1511831075      71c284321f6b        25 minutes ago      124MB
berndtj/dispatch-function-manager                                                            dev-1511831075      ef55b922b661        25 minutes ago      65.7MB
berndtj/dispatch-identity-manager                                                            dev-1511831075      cb045ec07d14        25 minutes ago      60.1MB
berndtj/dispatch-image-manager                                                               dev-1511831075      4efd00b0318f        25 minutes ago      61.4MB

Installing the Dispatch Chart

First create an docker authorization token for openfaas:

export OPENFAAS_AUTH=$(echo '{"username":"bjung","password":"********","email":"bjung@vmware.com"}' | base64)

The first time the chart is installed, chart dependencies must be fetched:

cd ./charts/dispatch
helm dep up
cd -

A values.yaml was created as an artifact of make images.

$ helm install ./charts/dispatch --name=dev-dispatch --namespace dispatch \
  -f values.yaml \
  --set function-manager.faas.openfaas.registryAuth=$OPENFAAS_AUTH \
  --set function-manager.faas.openfaas.imageRegistry=$DOCKER_REGISTRY \
  --set global.host=$DISPATCH_HOST \
  --set global.image.host=$DOCKER_REGISTRY \
  --set oauth2-proxy.app.clientID=$DISPATCH_OAUTH_CLIENT_ID  \
  --set oauth2-proxy.app.clientSecret=$DISPATCH_OAUTH_CLIENT_SECRET \
  --set oauth2-proxy.app.cookieSecret=$DISPATCH_OAUTH_COOKIE_SECRET \
  --debug

You can monitor the deployment with kubectl:

$ kubectl -n dispatch get deployment
NAME                              DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
dev-dispatch-api-manager        1         1         1            1           1h
dev-dispatch-echo-server        1         1         1            1           1h
dev-dispatch-event-manager      1         1         1            1           1h
dev-dispatch-function-manager   1         1         1            1           1h
dev-dispatch-identity-manager   1         1         1            1           1h
dev-dispatch-image-manager      1         1         1            1           1h
dev-dispatch-oauth2-proxy       1         1         1            1           1h
dev-dispatch-rabbitmq           1         1         1            1           1h
dev-dispatch-secret-store       1         1         1            1           1h
$ kubectl -n dispatch get service
NAME                              CLUSTER-IP   EXTERNAL-IP   PORT(S)                                 AGE
dev-dispatch-api-manager        10.0.0.179   <none>        80/TCP                                  1h
dev-dispatch-echo-server        10.0.0.58    <none>        80/TCP                                  1h
dev-dispatch-event-manager      10.0.0.13    <none>        80/TCP                                  1h
dev-dispatch-function-manager   10.0.0.145   <none>        80/TCP                                  1h
dev-dispatch-identity-manager   10.0.0.245   <none>        80/TCP                                  1h
dev-dispatch-image-manager      10.0.0.188   <none>        80/TCP                                  1h
dev-dispatch-oauth2-proxy       10.0.0.51    <none>        80/TCP,443/TCP                          1h
dev-dispatch-rabbitmq           10.0.0.180   <none>        4369/TCP,5672/TCP,25672/TCP,15672/TCP   1h
dev-dispatch-secret-store       10.0.0.249   <none>        80/TCP                                  1h

Test your Deployment

Test with `curl`

Check that the ingress controller is routing to the identity manager

$ curl -k https://dispatch.local/oauth2/start
<a href="https://github.com/login/oauth/authorize?approval_prompt=force&amp;client_id=8e3894cb0199f8342f0a&amp;redirect_uri=https%3A%2F%2Fdispatch.local%2Foauth2%2Fcallback&amp;response_type=code&amp;scope=openid%2C+user%3Aemail&amp;state=13939a602fb6704121766b0f5ba588cb%3A%2F">Found</a>.

Test with `dispatch` CLI

If you haven't already, build the dispatch CLI:

make cli-darwin
ln -s `pwd`/bin/dispatch-darwin /usr/local/bin/dispatch

In order to use the dispatch CLI, set $HOME/.dispatch.yaml to point to the new services:

$ cat << EOF > $HOME/.dispatch.yaml
host: $DISPATCH_HOST
port: 443
organization: vmware
cookie: ""
EOF

At this point the dispatch CLI should work:

$ dispatch login
You have successfully logged in, cookie saved to /Users/bjung/.dispatch.yaml
$ dispatch get image
Using config file: /Users/bjung/.dispatch.yaml
  NAME | URL | BASEIMAGE | STATUS | CREATED DATE

ayaflash/dispatch

Dispatch

Architecture

Quickstart

Assumptions:

Start Minikube and initialize Helm

Download Dispatch CLI

Configure and install Dispatch:

Execute a function:

Add an API endpoint:

Install Dispatch UI

Standard Installation

Prerequisites

Kubernetes

Minikube

Hosted Kubernetes

Helm

RBAC and Helm

Add the cluster-admin clusterrole (required for Kubernetes on OpenStack - VIOK):

Add the tiller service account (required for clusters created via Kops - AWS):

Download Helm and install tiller:

Set a Few Environment Variables

Configure Image Registry

Import self-signed TLS certificates into Kubernetes secret

Install Ingress Controller

Install FaaS (OpenFaaS)

Install Api-gateway (Kong)

Building and Deploying Dispatch

Building Images

Installing the Dispatch Chart

Test your Deployment

Test with curl

Test with dispatch CLI

Test with `curl`

Test with `dispatch` CLI