AZURE FUNCTIONS WITH GLOO

What you'll need

• Kubernetes v1.8+ deployed somewhere. Minikube is a great way to get a cluster up quickly.
• kubectl to interact with kubernetes.
• glooctl to interact with gloo.
• azure account

Setup the environment

Install Kubernetes

minikube start --extra-config=apiserver.Authorization.Mode=RBAC --cpus 4 --memory 4096
kubectl create clusterrolebinding permissive-binding \
         --clusterrole=cluster-admin \
         --user=admin \
         --user=kubelet \
         --group=system:serviceaccounts

Install Gloo

glooctl install kube

Wait \ Verify that all the pods are in Running status:

kubectl get pods --all-namespaces

Get the url of the ingress

If you installed kubernetes using minikube as mentioned above, you can use this command:

export GATEWAY_URL=http://$(minikube ip):$(kubectl get svc ingress -n gloo-system -o 'jsonpath={.spec.ports[?(@.name=="http")].nodePort}')

Steps

Create a directory for your project

mkdir joke-gen
cd joke-gen

Create an azure resource group via azure portal

Create an azure function app in the resource group

Select functions app from list

• Click create

• Give an application name
• Select your resource group previously created
• Give a name for storage account

• Click create

Get publish profile

• Click Get publish profile
• Save it in previously created directory

You should have file with a xml content looking like this

Create a very simple script to create kubernetes secret containing the publish profile data

(adjust the name of the secret in metadata)

#!/bin/bash
DATA=$(cat $1 | base64)

tee $2 <<EOF
apiVersion: v1
kind: Secret
metadata:
  name: joke-gen
data:
  publish_profile: $DATA
EOF

Generate the secret yaml file

bash gen-secret.sh publish-profile-filename yaml-secret-file-name
# eg: bash gen-secret.sh gloo-azure-app.PublishSettings secret.yaml

You should get something like this

Create the secret

Note - Don't forget to create secret in gloo-system namespace

# create
kubectl apply -f secret.yaml -n gloo-system

# check kubernetes
kubectl get secret -n gloo-system
+--------------------+------------------------------------+-------+-------+
|  NAME              |   TYPE                             | DATA  |   AGE |
+--------------------+------------------------------------+-------+-------+
|default-token-jrhbj | kubernetes.io/service-account-token|   3   |   3d  |
|joke-gen   Opaque   |                                    |   1   |   1m  |
+--------------------+------------------------------------+-------+-------+

# check gloo 
glooctl secret get

+---------------------+---------+-----------+
|        NAME         |  TYPE   | IN USE BY |
+---------------------+---------+-----------+
| default-token-jrhbj | Unknown |           |
| joke-gen            | Unknown |           |
+---------------------+---------+-----------+

Create an azure function

For example a function that retrieve Chuck Norris jokes from an api

Save and test the function

---

Create an upstream

• Create a file (upstream.yaml) with this content

name: joke-gen-upstream
type: azure
spec:
  secret_ref: joke-gen
  function_app_name: gloo-azure-app
metadata:
  annotations:
    gloo.solo.io/azure_publish_profile: joke-gen

where

• name is the name of the upstream
• secret_refis the name of the secret
• function_app_nameis the name of the Azure Functions App
• gloo.solo.io/azure_publish_profile is the name of the secret. this annotation is mandatory

• Create the upstream

glooctl upstream create -f upstream.yaml

+-------------------+-------+--------+----------+
|       NAME        | TYPE  | STATUS | FUNCTION |
+-------------------+-------+--------+----------+
| joke-gen-upstream | azure |        |          |
+-------------------+-------+--------+----------+

• Check functions discovery is ok

glooctl upstream get joke-gen-upstream
+-------------------+-------+--------+----------+
|       NAME        | TYPE  | STATUS | FUNCTION |
+-------------------+-------+--------+----------+
| joke-gen-upstream | azure |        | joke-gen |
+-------------------+-------+--------+----------+

You should see in column the names of your functions in azure function app

Create a route to the function

glooctl route create --sort \
   --upstream joke-gen-upstream \
   --function 'joke-gen' \
   --path-exact /joke

+----+------------+-------------+------+--------+-----------------------+----------+-----------+
| ID |  MATCHER   |    TYPE     | VERB | HEADER |         UPSTREAM      | FUNCTION | EXTENSION |
+----+------------+-------------+------+--------+-----------------------+----------+-----------+
| 1  | /joke      | Exact Path  | *    |        | joke-gen-upstream     | joke-gen |           |
+----+------------+-------------+------+--------+-----------------------+----------+-----------+
   

Get the url of the ingress

If you installed kubernetes using minikube, you can use this command:

export GATEWAY_URL=http://$(minikube ip):$(kubectl get svc ingress -n gloo-system -o 'jsonpath={.spec.ports[?(@.name=="http")].nodePort}')

Test

Try out the route using curl:

curl $GATEWAY_URL/joke

{"category":["dev"],"icon_url":"https://assets.chucknorris.host/img/avatar/chuck-norris.png","id":"ag_6paerrkg-mxfjjqw4ba","url":"https://api.chucknorris.io/jokes/ag_6paerrkg-mxfjjqw4ba","value":"Chuck Norris's beard can type 140 wpm."}