Deploy to Azure Functions with Azure Developer CLI

Azure Developer CLI (azd) supports code and container deployments to Azure Functions. Use the dedicated function host in azure.yaml for both modes:

• Code deployment packages your built function code as a zip archive and uploads it to the Function App.
• Container deployment builds or resolves a container image, publishes it to Azure Container Registry (ACR) when needed, and updates the Function App to run the image.

Azure Functions and Azure App Service both use the Microsoft.Web/sites resource provider, and their container deployment flows share some internal mechanics. However, they aren't the same azd host. Functions uses host: function, has Functions-specific packaging and remote-build behavior, and doesn't use the App Service deployment-slot workflow.

Choose a deployment mode

azd selects the deployment mode from the service configuration:

The provisioned Function App must use the same mode as the service configuration. If the Function App is configured for containers but azure.yaml selects code deployment, or the reverse, azd deploy stops before uploading and reports the mismatch.

Deploy function code

Configure a code-based function service with a source project, supported language, and host: function:

services:
  api:
    project: ./src/api
    language: ts
    host: function

During azd deploy, azd builds the project, applies .funcignore exclusions, creates a zip archive, and uploads the package through the Azure Functions deployment API.

Your Bicep or Terraform must provision a code-based Function App and tag it with azd-service-name set to the service name, unless you identify the resource by using resourceName in azure.yaml. Configure the hosting plan, runtime, storage, identities, networking, and application settings through infrastructure as code.

Configure remote builds for code deployments

The top-level service remoteBuild property applies only to code-based Function Apps on the Flex Consumption plan. It controls whether Azure Functions uses Oryx to build the uploaded package:

services:
  api:
    project: ./src/api
    language: python
    host: function
    remoteBuild: true

When you omit remoteBuild on Flex Consumption, azd selects a default based on the language and package contents:

For JavaScript and TypeScript, an explicitly configured remoteBuild value must agree with .funcignore when that file exists. Set remoteBuild: true when .funcignore excludes node_modules. Set remoteBuild: false when .funcignore includes node_modules in the package.

Don't set the top-level remoteBuild property for non-Flex plans. To enable an Oryx build on another supported plan, configure ENABLE_ORYX_BUILD=true and SCM_DO_BUILD_DURING_DEPLOYMENT=true as Function App settings in your infrastructure.

Deploy a containerized function

For a source project with a Dockerfile, set language: docker, or keep the source language and specify docker.path.

The following example uses a TypeScript project with a Dockerfile:

services:
  api:
    project: ./src/api
    language: ts
    host: function
    docker:
      path: ./Dockerfile

You can also deploy a prebuilt image without a local project:

services:
  api:
    host: function
    image: myregistry.azurecr.io/functions/api:1.0

For a prebuilt image, omit language or set it to docker. Don't combine image with project.

During a container deployment, azd:

1. Builds the image locally or remotely, or resolves the configured prebuilt image.
2. Publishes the image to the ACR instance configured for the project when publishing is required.
3. Updates the Function App's linuxFxVersion to DOCKER|<image>.
4. Deploys to the main Function App site.

The top-level service remoteBuild property doesn't apply to containers. To build a container image with ACR Tasks, use docker.remoteBuild:

services:
  api:
    project: ./src/api
    language: docker
    host: function
    docker:
      path: ./Dockerfile
      remoteBuild: true

Provision a container-ready Function App

azd deploy updates the image reference but doesn't convert a code-based Function App into a container-based Function App. Your infrastructure must provision a compatible site before deployment.

Service-level env settings aren't supported for the function host. Define Function App settings in your infrastructure instead.

Understand deployment slots

azd always deploys a function service to the main Function App site. It doesn't discover, prompt for, or deploy to Function App slots. App Service slot settings such as AZD_DEPLOY_{SERVICE}_SLOT_NAME don't affect a Function App deployment.

If you need a slot-based Functions release process, manage the slot and deployment outside the built-in host: function workflow.

Compare Functions and App Service hosts

Functions and App Service share the Microsoft.Web/sites resource type, but select the host that matches the workload:

Related content

• Azure Functions hosting options
• Create functions in custom containers
• Azure Developer CLI schema reference
• Configure service packaging file exclusions
• Use Docker support to deploy containerized apps in any language