Functions are blocks of code that run on demand without the need to manage any infrastructure. Develop on your local machine, test your code from the command line (using doctl
), then deploy to App Platform — no servers required. Learn more about functions.
You can start writing a function using either the doctl
command line tool or our control panel. The control panel is great for experimentation, but a command line workflow is the intended route for in-depth development of functions.
Make sure you have doctl
installed, authorized to access your DigitalOcean account, and set up with the serverless
extension. See How To Install and Configure doctl for instructions.
Run the serverless status
subcommand to verify that you’re properly set up to create and deploy functions:
doctl serverless status
If you receive output about the namespace you’re connected to, you’re all set:
Connected to function namespace 'fn-feb132ee-706a-4f13-9c81-f24a3330260b' on API host 'https://faas-nyc1-78edc.doserverless.co'
If you receive an error, be sure you completed all the steps of How To Install and Configure doctl and try again before continuing.
On your local machine, navigate to the directory where you’d like to put your function code, then use the serverless init
subcommand to initialize a sample project. The -l
or --language
flag specifies which programming language the sample project should use. The options are go
, javascript
, php
, and python
.
Create a sample project in the language of your choice:
doctl serverless init --language js <example-project>
Be sure to replace <example-project>
with your project name. A directory will be created with sample code and configuration files:
A local sandbox area 'example-project' was created for you.
The directory will have a project.yml
file in it, as well as a packages
directory containing the sample
package, the hello
function directory, and the sample “hello world” function code:
example-project/
├── packages
│ └── sample
│ └── hello
│ └── hello.js
└── project.yml
Next we’ll deploy the function.
Use serverless deploy
to deploy the sample “hello world” function. The subcommand takes one argument, a path to the project directory you just created.
serverless deploy
command overwrites previously deployed functions in a namespace if their project/function
names match the new deploy. This occurs even if the functions were created in separate projects.Run the deploy command now, being sure to substitute your own project name for <example-project>
:
doctl serverless deploy <example-project>
The command will output information about the deployment:
Deploying '/home/sammy/example-project'
to namespace 'fn-feb132ee-706a-4f13-9c81-f24a3330260b'
on host 'https://faas-nyc1-78edc.doserverless.co'
Deployment status recorded in 'example-project/.nimbella'
Deployed functions ('doctl sbx fn get <funcName> --url' for URL):
- sample/hello
The function is now deployed to the cloud as sample/hello
.
Deployed functions can be invoked using the serverless functions invoke
command:
doctl serverless functions invoke sample/hello
The function will return a JSON response:
{
"body": "Hello stranger!"
}
The sample function accepts a name
parameter to customize the greeting. You can add key:value
parameters to serverless functions invoke
using the -p
flag:
doctl serverless functions invoke sample/hello -p name:sammy
The response will be customized based on your input:
{
"body": "Hello sammy!"
}
Use the serverless undeploy
subcommand to remove functions from the cloud:
doctl serverless undeploy sample/hello
The command will verify that the process was successful:
The requested resources have been undeployed
Your function is now undeployed from Functions.
Go to https://cloud.digitalocean.com/functions and click Launch.
If you have any functions, they’ll be listed by name on the Overview tab:
Click the “more menu” button to the right of the function you’d like to destroy, then choose Destroy Function.
You will be prompted to confirm the action. Enter the function name to confirm, the press Destroy.
The Functions development environment enables you to connect your local workspace to the cloud. Using the doctl
CLI command, you can deploy functions from your development machine to the Functions cloud, then test and iterate before deploying as an App Platform component.