title | description | ms.date | ms.topic | ms.devlang | ms.custom | zone_pivot_groups |
---|---|---|---|---|---|---|
Create a TypeScript function from the command line - Azure Functions | Learn how to create a TypeScript function from the command line, then publish the local project to serverless hosting in Azure Functions. | 12/15/2023 | quickstart | typescript | devx-track-azurecli, devx-track-azurepowershell, mode-other, devx-track-js, devx-track-ts | functions-nodejs-model |
In this article, you use command-line tools to create a TypeScript function that responds to HTTP requests. After testing the code locally, you deploy it to the serverless environment of Azure Functions.
[!INCLUDE functions-nodejs-model-pivot-description]
Completion of this quickstart incurs a small cost of a few USD cents or less in your Azure account.
There's also a Visual Studio Code-based version of this article.
Before you begin, you must have the following prerequisites:
An Azure account with an active subscription. Create an account for free.
One of the following tools for creating Azure resources:
Azure CLI version 2.4 or later.
The Azure Az PowerShell module version 5.9.0 or later.
::: zone pivot="nodejs-model-v3"
Node.js version 14 or above. ::: zone-end ::: zone pivot="nodejs-model-v4"
Node.js version 18 or above.
TypeScript version 4+. ::: zone-end
[!INCLUDE functions-install-core-tools]
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- Make sure you install version v4.0.5382 of the Core Tools, or a later version.
::: zone-end
In Azure Functions, a function project is a container for one or more individual functions that each responds to a specific trigger. All functions in a project share the same local and hosting configurations. In this section, you create a function project that contains a single function.
::: zone pivot="nodejs-model-v3"
In a suitable folder, run the
func init
command, as follows, to create a TypeScript Node.js v3 project in the current folder:func init --typescript --model V3
This folder now contains various files for the project, including configurations files named local.settings.json and host.json. Because local.settings.json can contain secrets downloaded from Azure, the file is excluded from source control by default in the .gitignore file.
Add a function to your project by using the following command, where the
--name
argument is the unique name of your function (HttpExample) and the--template
argument specifies the function's trigger (HTTP).func new --name HttpExample --template "HTTP trigger" --authlevel "anonymous"
func new
creates a subfolder matching the function name that contains a code file appropriate to the project's chosen language and a configuration file named function.json.
If desired, you can skip to Run the function locally and examine the file contents later.
index.ts exports a function that's triggered according to the configuration in function.json.
:::code language="typescript" source="~/functions-quickstart-templates/Functions.Templates/Templates/HttpTrigger-TypeScript/index.ts":::
For an HTTP trigger, the function receives request data in the variable req
of type HttpRequest as defined in function.json. The return object, defined as $return
in function.json, is the response.
function.json is a configuration file that defines the input and output bindings
for the function, including the trigger type.
:::code language="json" source="~/functions-quickstart-templates/Functions.Templates/Templates/HttpTrigger-JavaScript/function.json":::
Each binding requires a direction, a type, and a unique name. The HTTP trigger has an input binding of type httpTrigger
and output binding of type http
.
::: zone-end
::: zone pivot="nodejs-model-v4"
In a suitable folder, run the
func init
command, as follows, to create a TypeScript Node.js v4 project in the current folder:func init --typescript
This folder now contains various files for the project, including configurations files named local.settings.json and host.json. Because local.settings.json can contain secrets downloaded from Azure, the file is excluded from source control by default in the .gitignore file. Required npm packages are also installed in node_modules.
Add a function to your project by using the following command, where the
--name
argument is the unique name of your function (HttpExample) and the--template
argument specifies the function's trigger (HTTP).func new --name HttpExample --template "HTTP trigger" --authlevel "anonymous"
func new
creates a file named HttpExample.ts in the src/functions directory, which contains your function's code.Add Azure Storage connection information in local.settings.json.
{ "Values": { "AzureWebJobsStorage": "<Azure Storage connection information>", "FUNCTIONS_WORKER_RUNTIME": "node" } }
(Optional) If you want to learn more about a particular function, say HTTP trigger, you can run the following command:
func help httptrigger
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Run your function by starting the local Azure Functions runtime host from the LocalFunctionProj folder:
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npm installnpm start
::: zone-end
::: zone pivot="nodejs-model-v4"
npm start
::: zone-end
Toward the end of the output, the following logs should appear:
[!NOTE] If HttpExample doesn't appear as shown in the logs, you likely started the host from outside the root folder of the project. In that case, use Ctrl+c to stop the host, navigate to the project's root folder, and run the previous command again.
Copy the URL of your
HttpExample
function from this output to a browser and append the query string?name=<your-name>
, making the full URL likehttp://localhost:7071/api/HttpExample?name=Functions
. The browser should display a message likeHello Functions
:The terminal in which you started your project also shows log output as you make requests.
When you're ready, use Ctrl+c and choose y to stop the functions host.
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Create the function app in Azure:
az functionapp create --resource-group AzureFunctionsQuickstart-rg --consumption-plan-location <REGION> --runtime node --runtime-version 18 --functions-version 4 --name <APP_NAME> --storage-account <STORAGE_NAME>
The az functionapp create command creates the function app in Azure. It's recommended that you use the latest version of Node.js, which is currently 18. You can specify the version by setting
--runtime-version
to18
.New-AzFunctionApp -Name <APP_NAME> -ResourceGroupName AzureFunctionsQuickstart-rg -StorageAccount <STORAGE_NAME> -Runtime node -RuntimeVersion 18 -FunctionsVersion 4 -Location '<REGION>'
The New-AzFunctionApp cmdlet creates the function app in Azure. It's recommended that you use the latest version of Node.js, which is currently 18. You can specify the version by setting
--runtime-version
to18
.In the previous example, replace
<STORAGE_NAME>
with the name of the account you used in the previous step, and replace<APP_NAME>
with a globally unique name appropriate to you. The<APP_NAME>
is also the default DNS domain for the function app.This command creates a function app running in your specified language runtime under the Azure Functions Consumption Plan, which is free for the amount of usage you incur here. The command also creates an associated Azure Application Insights instance in the same resource group, with which you can monitor your function app and view logs. For more information, see Monitor Azure Functions. The instance incurs no costs until you activate it.
Before you use Core Tools to deploy your project to Azure, you create a production-ready build of JavaScript files from the TypeScript source files.
Use the following command to prepare your TypeScript project for deployment:
npm run build
With the necessary resources in place, you're now ready to deploy your local functions project to the function app in Azure by using the publish command. In the following example, replace
<APP_NAME>
with the name of your app.func azure functionapp publish <APP_NAME>
If you see the error, "Can't find app with name ...", wait a few seconds and try again, as Azure may not have fully initialized the app after the previous
az functionapp create
command.The publish command shows results similar to the following output (truncated for simplicity):
... Getting site publishing info... Creating archive for current directory... Performing remote build for functions project. ... Deployment successful. Remote build succeeded! Syncing triggers... Functions in msdocs-azurefunctions-qs: HttpExample - [httpTrigger] Invoke url: https://msdocs-azurefunctions-qs.azurewebsites.net/api/httpexample?code=KYHrydo4GFe9y0000000qRgRJ8NdLFKpkakGJQfC3izYVidzzDN4gQ==
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[!INCLUDE functions-cleanup-resources-cli]
[!div class="nextstepaction"] Connect to an Azure Storage queue