dapr-aci

Dapr sidecar in ACI

Demo of Dapr sidecar in Azure Container Instances (ACI)

Setup

This demo illustrates simple service subscription to pub/sub topic and persistence of event payload into state. To deploy Dapr into ACI however you will need to first setup a SMB volume which will be used to store the Dapr components and mounted in the daprd container The storage account name needs to be globally unique so set SNAME to something 3-24 chars long, containing alphanumerics only, and make sure it's all in lower case.

export SNAME="dapraci"

assumes your resource group and location defaults are already set. If not, set them now:

az account set --subscription <id or name>
az configure --defaults location=<preferred location> group=<preferred resource group>

Create a storage account

az storage account create --name $SNAME --sku Standard_LRS

Create a storage share

For demo purposes share and storage user names are the same

az storage share create --name $SNAME --account-name $SNAME

Capture storage key

export ACCOUNT_KEY=$(az storage account keys list --account-name $SNAME \
                                                  --query "[0].value" \
                                                  --output tsv)
echo $ACCOUNT_KEY

Now update volumes[components].azureFile.storageAccountKey in configuration/app.yaml file so that ACI can mount it.

Upload the Dapr component files

az storage file upload --account-key $ACCOUNT_KEY \
                       --account-name $SNAME \
                       --share-name $SNAME \
                       --source components/state.yaml

az storage file upload --account-key $ACCOUNT_KEY \
                       --account-name $SNAME \
                       --share-name $SNAME \
                       --source components/pubsub.yaml

List files to make sure they are all there

az storage file list \
    --account-key $ACCOUNT_KEY \
    --share-name $SNAME \
    --account-name $SNAME  \
    --output tsv

Deployment

Once the storage is set up, you can deploy

az container create -f deployment/app.yaml

When you list the containers:

az container list -o table

The result should look something like this:

Name      ResourceGroup    Status     Image                                                IP:ports               Network    CPU/Memory       OsType    Location
--------  ---------------  ---------  ---------------------------------------------------  ---------------------  ---------  ---------------  --------  ----------
dapraci   mchmarny         Succeeded  daprio/daprd:0.11.3,ghcr.io/mchmarny/aci-app:v0.2.2  40.xx.xx.xx:3500       Public     1.0 core/1.5 gb  Linux     westus2

Demo

First, capture the IP for ease of access:

export APP_IP=$(az container show -n dapraci --query "ipAddress.ip" -o tsv)

Next, invoke the ping method thru Dapr API:

curl -i -d '{"message":"ping"}' \
     -H "Content-type: application/json" \
     "http://${APP_IP}:3500/v1.0/invoke/dapraci/method/ping"

Response should look something like this:

{ "on": 1604003460965972895, "greeting": "pong" }

You can also invoke the PubSub API on Dapr to publish:

curl -i -d '{"message":"hello"}' \
     -H "Content-type: application/json" \
     "http://${APP_IP}:3500/v1.0/publish/pubsub/messages"

Response from post has no body but you should see the headers:

HTTP/1.1 200 OK
Server: fasthttp
Date: Thu, 29 Oct 2020 21:05:43 GMT
Content-Length: 0
Traceparent: 00-bd0f6f745de1b2cc8b5463f8abaa8656-d2f1d6be6d202273-00

This demo also exposes the user container directly. You can disable it but commenting out - port: 8080 in ports section of configuration/app.yaml. To invoke the /ping route on the deployed app:

curl -i -d '{"message":"ping"}' \
     -H "Content-type: application/json" \
     "http://${APP_IP}:8082/ping"

Logs

To view logs from the Dapr container:

az container logs --name dapraci --container-name daprd

Note, daprd is set to log in JSON so you can use jq or similar to query the logs and parse out only the messages

az container logs --name dapraci --container-name daprd | jq ".msg"

To query the app container:

az container logs --name dapraci --container-name app

That's it, I hope you found it helpful.

Todo

• Dapr API token auth
• Configuration to show ACT
• Secrets to enable Azure Vault

Disclaimer

This is my personal project and it does not represent my employer. While I do my best to ensure that everything works, I take no responsibility for issues caused by this code.

License

This software is released under the MIT