How to Use the Command 'serverless' (with Examples)

The serverless framework is a robust toolkit designed for deploying and operating serverless architectures on popular cloud providers such as AWS, Google Cloud, Azure, and IBM OpenWhisk. By abstracting much of the overhead involved in configuring cloud environments, Serverless enables developers to focus on writing functions and deploying them with minimal hassle. The command-line utility allows developers to rapidly create, deploy, and manage serverless projects with relatively few commands. With serverless, and its alias sls, operations such as creating projects, deploying code, and managing function invocation and logs are streamlined significantly.

Use Case 1: Create a Serverless Project

Code:

serverless create

Motivation:

When venturing into serverless architecture, the initial step involves setting up a project environment. serverless create provides an out-of-the-box scaffold for new projects, setting up initial directory structures and configuration files conducive for building serverless applications. Incorporating this command streamlines initiating projects, especially for teams new to the serverless paradigm, by reducing manual setup.

Explanation:

• serverless – invokes the serverless framework tool from the command line.
• create – specifies the action to create a new serverless project environment.

Example Output:

Serverless: Generating boilerplate...
Serverless: Generating boilerplate in "/path/to/your/project"
Serverless: Successfully generated boilerplate for your project

Use Case 2: Create a Serverless Project from a Template

Code:

serverless create --template template_name

Motivation:

Templates further expedite the process of setting up new projects by providing pre-configured setups tailored for different use cases or languages. This can be particularly useful when projects adhere to standards or utilize specific technology stacks. Templates minimize configuration errors and speed up the onboarding process for new team members by leveraging established best practices.

Explanation:

• serverless – the primary command for initiating serverless operations.
• create – instructs the tool to begin creating a new project.
• --template template_name – specifies a particular template to mold the new project, where template_name could represent frameworks like aws-nodejs or google-python.

Example Output:

Serverless: Generating boilerplate from specified template...
Serverless: Downloading template "template_name"...
Serverless: Successfully installed template into "/path/to/your/template_project"

Use Case 3: Deploy to a Cloud Provider

Code:

serverless deploy

Motivation:

Deploying serverless functions to the cloud is the core reason for utilizing serverless technologies. serverless deploy automates this deployment, allowing developers to push their code and its infrastructure configurations to their chosen cloud provider with ease. It handles integrating the functions with cloud resources and managing their uptime capabilities, effectively abstracting complex deployment processes, allowing developers to focus on functionality.

Explanation:

• serverless – the framework’s command-line tool for interactions.
• deploy – the command to deploy configured serverless functions and resources to the specified cloud provider.

Example Output:

Serverless: Packaging service...
Serverless: Excluding development dependencies...
Serverless: Creating Stack...
Serverless: Checking Stack create progress...
.......... 
Serverless: Stack update finished...
Service Information
...
endpoints:
  GET - https://xyz.amazonaws.com/dev/function
functions:
  hello: your-serverless-project-dev-hello

Use Case 4: Display Information About a Serverless Project

Code:

serverless info

Motivation:

Understanding the state and specifics of your serverless deployment is invaluable in managing ongoing projects. The serverless info command surfaces critical details about the current project deployment, such as endpoints and resource statuses. This is especially useful for teams looking to perform quality assurance, implement integrations, or troubleshoot issues, as it neatly summarizes the project’s configuration and access points.

Explanation:

• serverless – the operational command-line interface for serverless tasks.
• info – requests detailed information regarding the present configuration and status of deployed serverless resources.

Example Output:

Service Information
service: your-serverless-project
stage: dev
region: us-east-1
stack: your-serverless-project-dev
endpoints:
  GET - https://abc.amazonaws.com/dev/hello
functions:
  hello: your-serverless-project-dev-hello

Use Case 5: Invoke a Deployed Function

Code:

serverless invoke -f function_name

Motivation:

Testing and interacting with your serverless functions directly in the cloud can be vital for debugging and verifying deployment integrity. serverless invoke provides a means to execute functions immediately, simulating what a real-world user might trigger. This can be particularly useful for development and testing environments, ensuring that functions respond appropriately before being used in production settings.

Explanation:

• serverless – calling the framework’s command-line tool.
• invoke – instructs a specific function invocation within the deployed environment.
• -f function_name – specifies the function to invoke, where function_name represents your deployed function, for example, hello.

Example Output:

Serverless: Running "serverless" command...
{
    "statusCode": 200,
    "body": "{\"message\":\"Hello from serverless!\"}"
}

Use Case 6: Follow the Logs for a Project

Code:

serverless logs -t

Motivation:

Monitoring logs in real-time is essential to diagnosing issues as they arise in serverless applications. serverless logs -t provides ongoing log tracking of deployed functions, crucial for maintaining system health and catching anomalies in real-time. Operations teams and developers benefit from this by ensuring that errors can be spotted and resolved quickly, promoting better operational efficiency and reducing downtimes.

Explanation:

• serverless – the fundamental CLI tool for serverless management.
• logs – retrieves log information for specific functions or services.
• -t – follows the log stream in real-time, effectively producing a live feed of log events.

Example Output:

START RequestId: abc123 Version: $LATEST
2019-09-10T01:00:00.123Z abc123 INFO Processing event...
2019-09-10T01:00:01.456Z abc123 INFO Event processed successfully
END RequestId: abc123
REPORT RequestId: abc123 Duration: 1000 ms Billed Duration: 2000 ms Memory Size: 128 MB Max Memory Used: 100 MB

Conclusion:

The Serverless Framework profoundly enhances the efficiency of creating, deploying, and managing cloud-based serverless applications. Through a simplified command-line interface, vast operational tasks such as project generation, deployment, invocation, and logging become more manageable and less error-prone. These use cases exemplify how each command contributes to a streamlined serverless development cycle, enabling rapid iteration and reliable deployment of cloud-native applications.