API deployment and stages in AWS - Step-by-Step Execution

Process Flow - API deployment and stages

Create API Definition

↓

Deploy API to Stage

↓

Stage Created with URL

↓

Client Calls Stage URL

↓

API Gateway Routes Request

↓

Backend Service Responds

↓

Response Returned to Client

This flow shows how an API is created, deployed to a stage, and then accessed by clients through that stage URL.

Execution Sample

AWS

aws apigateway create-rest-api --name MyAPI
aws apigateway create-deployment --rest-api-id abc123 --stage-name prod
curl https://abc123.execute-api.region.amazonaws.com/prod/resource

Creates an API, deploys it to a 'prod' stage, and calls the deployed API endpoint.

Process Table

Step	Action	Input/Parameters	Result/Output	Notes
1	Create API	Name=MyAPI	API ID=abc123	API created with unique ID
2	Create Deployment	API ID=abc123, Stage=prod	Deployment ID=dep456, Stage URL=https://abc123.execute-api.region.amazonaws.com/prod	API deployed to 'prod' stage
3	Client Call	URL=https://abc123.execute-api.region.amazonaws.com/prod/resource	Request routed to backend, Response=200 OK	Client accesses deployed API
4	Update API	Add new resource or method	API definition updated	Changes made but not live until redeployed
5	Create New Deployment	API ID=abc123, Stage=prod	Deployment ID=dep789, Stage URL unchanged	New deployment updates stage with latest API
6	Client Call	URL=https://abc123.execute-api.region.amazonaws.com/prod/resource	Request routed to updated backend, Response=200 OK	Client accesses updated API
7	Exit	No further deployments	API stable at 'prod' stage	Execution stops as no new deployments

💡 No new deployments created, API stage remains stable

Status Tracker

Variable	Start	After Step 1	After Step 2	After Step 4	After Step 5	Final
API ID	None	abc123	abc123	abc123	abc123	abc123
Deployment ID	None	None	dep456	dep456	dep789	dep789
Stage Name	None	None	prod	prod	prod	prod
Stage URL	None	None	https://abc123.execute-api.region.amazonaws.com/prod	https://abc123.execute-api.region.amazonaws.com/prod	https://abc123.execute-api.region.amazonaws.com/prod	https://abc123.execute-api.region.amazonaws.com/prod
API Definition	Empty	Created	Created	Updated	Updated	Updated

Key Moments - 2 Insights

Why does updating the API definition not immediately change the live API?

Because the API must be redeployed to a stage after updates. See step 4 and 5 in the execution_table where the API is updated but only after step 5 deployment does the stage reflect changes.

What is the purpose of stages in API deployment?

Stages provide separate deployment environments (like 'prod' or 'dev') with unique URLs. This lets you test changes in one stage without affecting others. The execution_table shows deployment to 'prod' stage creating a stage URL.

Visual Quiz - 3 Questions

Look at the execution_table, what is the Deployment ID after the first deployment?

A dep456

B abc123

C dep789

D prod

💡 Hint

Check the 'Result/Output' column in step 2 of the execution_table.

At which step does the API stage URL become available?

A Step 4

B Step 1

C Step 2

D Step 5

💡 Hint

Look for when the 'Stage URL' is first shown in the execution_table.

If you update the API but do not create a new deployment, what happens when clients call the stage URL?

A They get the updated API response

B They get the old API response

C They get an error

D The stage URL changes

💡 Hint

Refer to steps 4 and 5 in the execution_table and variable_tracker for API Definition and Deployment ID.

Concept Snapshot

API Deployment and Stages:
- Create API to get API ID
- Deploy API to a stage (e.g., 'prod') to get a stage URL
- Clients call the stage URL to access the API
- Updating API requires redeployment to update the stage
- Stages isolate environments for testing and production

Full Transcript

This visual execution traces the process of deploying an API in AWS API Gateway. First, an API is created and assigned an ID. Then, the API is deployed to a stage, which creates a unique URL for clients to call. Clients use this URL to send requests that API Gateway routes to backend services. When the API definition changes, these changes do not affect the live stage until a new deployment is created. Stages allow separation of environments like development and production. The execution table shows each step, including creating the API, deploying it, client calls, updating the API, and redeploying. Variable tracking shows how API ID, deployment ID, stage name, and URL evolve. Key moments clarify why redeployment is needed and the role of stages. The quiz tests understanding of deployment IDs, stage URL availability, and behavior when redeployment is skipped.

Practice

1. What is the main purpose of an API stage in AWS API Gateway?

easy

A. To monitor network traffic outside AWS

B. To store API keys for users

C. To create backend Lambda functions

D. To manage different versions or environments of the API

Solution

1. Step 1: Understand API stages concept

   API stages in AWS API Gateway represent different versions or environments like development, testing, or production.

2. Step 2: Identify the role of stages

   Stages allow you to deploy and manage separate API versions independently.

3. Final Answer:

   To manage different versions or environments of the API -> Option D

4. Quick Check:

   API stages = version/environment management [OK]

Hint: Stages separate API versions or environments [OK]

Common Mistakes:

• Confusing stages with API keys
• Thinking stages create backend functions
• Assuming stages monitor external traffic

2. Which AWS CLI command is used to create a new deployment for an API Gateway REST API?

easy

A. aws apigateway create-deployment

B. aws apigateway create-stage

C. aws apigateway deploy-api

D. aws apigateway new-deployment

Solution

1. Step 1: Identify the correct AWS CLI command for deployment

   The command to create a deployment in API Gateway is create-deployment.

2. Step 2: Differentiate from other commands

   create-stage creates a stage, not a deployment. Other options are invalid commands.

3. Final Answer:

   aws apigateway create-deployment -> Option A

4. Quick Check:

   Deployment command = create-deployment [OK]

Hint: Deploy with 'create-deployment' command [OK]

Common Mistakes:

• Using create-stage instead of create-deployment
• Assuming deploy-api is a valid command
• Confusing deployment with stage creation

3. Given the following AWS CLI command:
aws apigateway create-stage --rest-api-id abc123 --stage-name prod --deployment-id dep456
What does this command do?

medium

A. Creates a new deployment named 'prod' for API 'abc123'

B. Creates a new stage 'prod' linked to deployment 'dep456' for API 'abc123'

C. Deletes the stage 'prod' from API 'abc123'

D. Updates the deployment 'dep456' with stage 'prod'

Solution

1. Step 1: Analyze the command parameters

   The command is create-stage with parameters for API ID, stage name, and deployment ID.

2. Step 2: Understand the effect of create-stage

   This creates a new stage named 'prod' that points to the deployment 'dep456' for the API 'abc123'.

3. Final Answer:

   Creates a new stage 'prod' linked to deployment 'dep456' for API 'abc123' -> Option B

4. Quick Check:

   create-stage + deployment-id = new stage linked to deployment [OK]

Hint: create-stage links stage to deployment by deployment-id [OK]

Common Mistakes:

• Confusing stage creation with deployment creation
• Thinking it deletes or updates instead
• Mixing up stage name and deployment ID

4. You ran this command to deploy your API stage:
aws apigateway create-stage --rest-api-id abc123 --stage-name test --deployment-id dep789
But you get an error saying the deployment ID does not exist. What is the likely cause?

medium

A. The deployment ID 'dep789' was not created before creating the stage

B. The stage name 'test' is invalid

C. The rest-api-id 'abc123' is incorrect format

D. You must create the stage before creating the deployment

Solution

1. Step 1: Understand the dependency between deployment and stage

   A stage must point to an existing deployment. If deployment ID does not exist, stage creation fails.

2. Step 2: Identify the error cause

   The error indicates deployment 'dep789' was not created or is invalid before stage creation.

3. Final Answer:

   The deployment ID 'dep789' was not created before creating the stage -> Option A

4. Quick Check:

   Stage needs existing deployment ID [OK]

Hint: Create deployment before stage with deployment ID [OK]

Common Mistakes:

• Assuming stage name format causes error
• Thinking API ID format is the issue
• Believing stage must be created before deployment

5. You want to deploy a new version of your API to a 'prod' stage without affecting the current live API. Which sequence of AWS CLI commands should you use?

hard

A. aws apigateway create-deployment -> aws apigateway create-stage with 'prod'

B. aws apigateway create-stage with 'prod' -> aws apigateway create-deployment

C. aws apigateway create-deployment -> aws apigateway update-stage with 'prod'

D. aws apigateway update-stage with 'prod' -> aws apigateway create-deployment

Solution

1. Step 1: Deploy new API version

   First, create a new deployment to capture the latest API changes.

2. Step 2: Update existing 'prod' stage to point to new deployment

   Use update-stage to switch the 'prod' stage to the new deployment without creating a new stage.

3. Final Answer:

   aws apigateway create-deployment -> aws apigateway update-stage with 'prod' -> Option C

4. Quick Check:

   Deploy then update stage to switch versions [OK]

Hint: Create deployment then update existing stage [OK]

Common Mistakes:

• Creating a new stage instead of updating existing
• Updating stage before deployment exists
• Assuming create-stage can update existing stage