Automating deployments is something I always enjoy. However, it's true that it often takes more time than a simple "right-click deploy." Plus, you may need to know different technologies and scripting languages.
But what if there was a tool that could help you write everything you need—Infrastructure as Code (IaC) files, scripts to copy files, and scripts to populate a database? In this post, we'll explore how the Azure Developer CLI (azd) can make deployments much easier.
What do we want to do?
Our goal: Deploy the 2D6 Dungeon App to Azure Container Apps.
This .NET Aspire solution includes:
- A frontend
- A data API
- A database
The Problem
In a previous post, we showed how azd up can easily deploy web apps to Azure.
If we try the same command for this solution, the deployment will be successful—but incomplete:
- The .NET Blazor frontend is deployed perfectly.
- However, the app fails when trying to access data.
- Looking at the logs, we see the database wasn't created or populated, and the API container fails to start.
Let's look more closely at these issues.
The Database
When running the solution locally, Aspire creates a MySQL container and executes SQL scripts to create and populate the tables. This is specified in the AppHost project:
var mysql = builder.AddMySql("sqlsvr2d6")
.WithLifetime(ContainerLifetime.Persistent);
var db2d6 = mysql.AddDatabase("db2d6");
mysql.WithInitBindMount(source: "../../database/scripts", isReadOnly: false);
When MySQL starts, it looks for SQL files in a specific folder and executes them. Locally, this works because the bind mount is mapped to a local folder with the files.
However, when deployed to Azure:
- The mounts are created in Azure Storage Files
- The files are missing!
The Data API
This project uses Data API Builder (dab). Based on a single config file, a full data API is built and hosted in a container.
Locally, Aspire creates a DAB container and reads the JSON config file to create the API. This is specified in the AppHost project:
var dab = builder.AddDataAPIBuilder("dab", ["../../database/dab-config.json"])
.WithReference(db2d6)
.WaitFor(db2d6);
But once again, when deployed to Azure, the file is missing. The DAB container starts but fails to find the config file.
The Solution
The solution is simple: the SQL scripts and DAB config file need to be uploaded into Azure Storage Files during deployment.
You can do this by adding a post-provision hook in the azure.yaml file to execute a script that uploads the files. See an example of a post-provision hook in this post.
Alternatively, you can leverage azd alpha features: azd.operations and infraSynth.
azd.operationsextends the provisioning providers and will upload the files for us.infraSynthgenerates the IaC files for the entire solution.
đź’ˇNote: These features are in alpha and subject to change.
Each azd alpha feature can be turned on individually. To see all features:
azd config list-alpha
To activate the features we need:
azd config set alpha.azd.operations on
azd config set alpha.infraSynth on
Let's Try It
Once the azd.operation feature is activated, any azd up will now upload the files into Azure. If you check the database, you'll see that the db2d6 database was created and populated. Yay!
However, the DAB API will still fail to start. Why? Because, currently, DAB looks for a file, not a folder, when it starts. This can be fixed by modifying the IaC files.
One Last Step: Synthesize the IaC Files
First, let's synthesize the IaC files. These Bicep files describe the required infrastructure for our solution.
With the infraSynth feature activated, run:
azd infra synth
You'll now see a new infra folder under the AppHost project, with YAML files matching the container names. Each file contains the details for creating a container.
Open the dab.tmpl.yaml file to see the DAB API configuration. Look for the volumeMounts section. To help DAB find its config file, add subPath: dab-config.json to make the binding more specific:
containers:
- image: {{ .Image }}
name: dab
env:
- name: AZURE_CLIENT_ID
value: {{ .Env.MANAGED_IDENTITY_CLIENT_ID }}
- name: ConnectionStrings__db2d6
secretRef: connectionstrings--db2d6
volumeMounts:
- volumeName: dab-bm0
mountPath: /App/dab-config.json
subPath: dab-config.json
scale:
minReplicas: 1
maxReplicas: 1
You can also specify the scaling minimum and maximum number of replicas if you wish.
Now that the IaC files are created, azd will use them. If you run azd up again, the execution time will be much faster—azd deployment is incremental and only does "what changed."
The Final Result
The solution is now fully deployed:
- The database is there with the data
- The API works as expected
- You can use your application!
Bonus: Deploying with CI/CD
Want to deploy with CI/CD? First, generate the GitHub Action (or Azure DevOps) workflow with:
azd pipeline config
Then, add a step to activate the alpha feature before the provisioning step in the azure-dev.yml file generated by the previous command.
- name: Extends provisioning providers with azd operations
run: azd config set alpha.azd.operations on
With these changes, and assuming the infra files are included in the repo, the deployment will work on the first try.
Conclusion
It's exciting to see how tools like azd are shaping the future of development and deployment. Not only do they make the developer's life easier today by automating complex tasks, but they also ensure you're ready for production with all the necessary Infrastructure as Code (IaC) files in place. The journey from code to cloud has never been smoother!
If you have any questions or feedback, I'm always happy to help—just reach out on your favorite social media platform.
