Modernizing Infrastructure and Applications with Google Cloud · Topic 5 of 5
APIs and Apigee
What an API is, how public APIs create new business and revenue, and the business value of Apigee API Management, explained for the Cloud Digital Leader exam.
- 4 min
- An API lets software use another system's data or functions without knowing its internals.
- APIs enable reuse, integration, partner ecosystems and modernization.
- Public APIs can create revenue, new channels and partner innovation.
What it is
An application programming interface (API) is a defined way for one piece of software to request data or actions from another, without knowing how the other works inside. APIs connect applications, partners and devices. Apigee API Management is Google Cloud's platform to design, secure, publish, analyze and monetize APIs.
How it works
APIs in plain words
Think of an API as a restaurant menu and waiter. You choose from the menu (the API's operations), the waiter takes the request to the kitchen (the backend) and brings back the dish (the response). You never see the kitchen. In the same way, a mobile app asks an API "show my orders" and gets the result without touching the database.
Benefits for the business:
| Benefit | Example |
|---|---|
| Reuse | One "check stock" API serves the website, app and stores |
| Faster development | Teams build on existing APIs instead of rebuilding features |
| Integration | Connect old systems to new apps without rewriting them |
| Partner ecosystems | Partners build products on your services |
| Modernization | Put an API in front of a legacy system, then replace it later without breaking apps |
New business through public APIs
Exposing APIs to outside developers and partners can create new revenue and reach:
| Opportunity | Example |
|---|---|
| Direct monetization | Charge per call or by subscription for data or services, such as weather or payment APIs |
| New channels | A travel site sells a hotel's rooms through its booking API |
| Partner innovation | Developers build apps on a bank's open banking APIs |
| Platform growth | More partners using your APIs makes your platform more valuable |
When a scenario says the company wants partners to "build on" its services or to "charge for data access", the answer involves exposing and monetizing APIs, usually with Apigee.
Business value of Apigee API Management
| Capability | Business value |
|---|---|
| Security | Authentication, authorization and threat protection in front of backends |
| Traffic management | Quotas and rate limits protect backends from overload and abuse |
| Analytics | See who uses which API, how often and with what errors, to improve products |
| Developer portal | Partners discover APIs, read documentation and get keys on their own |
| Monetization | Define rate plans and charge for API use |
| Mediation and modernization | Put a modern API in front of legacy systems and change backends without breaking consumers |
| Hybrid deployment | Manage APIs whose backends run in Google Cloud, on premises or other clouds |
Without API management, each team secures, documents and meters its APIs differently, which is slow and risky. Apigee gives one consistent layer.
A worked scenario
A logistics company wants online shops to show live delivery tracking. It exposes a tracking API through Apigee. Shops sign up on the developer portal, receive keys and pay per thousand calls (monetization). Quotas stop any shop from overloading the old tracking system behind the API, analytics show which partners use it most, and later the company replaces the legacy backend without the shops noticing.
How the exam asks about this
- "What is an API?" A defined interface that lets software request data or actions from other software.
- "Charge partners for access to our data." Monetize public APIs with Apigee.
- "Protect a legacy backend from too many requests." Apigee quotas and rate limits.
- "Let partners discover and test our APIs." Apigee developer portal.
What to remember for the exam
- An API lets software use another system's data or functions without knowing its internals.
- APIs enable reuse, integration, partner ecosystems and modernization.
- Public APIs can create revenue, new channels and partner innovation.
- Apigee: security, traffic management, analytics, developer portal, monetization, legacy modernization, hybrid.
An API is not a user interface. It is for software to talk to software.
Common mistakes
Thinking APIs are only technical plumbing. The exam stresses their business value and revenue potential.
Choosing a load balancer to manage partner access. Rate plans, keys and developer portals are API management, which is Apigee.
Assuming legacy systems must be rewritten first. An API layer can modernize access while the backend stays.
Check yourself
What is an API?
A defined interface that lets one application request data or actions from another without knowing how it works inside.
How can a company earn money from APIs?
By exposing them publicly and charging for their use, for example per call or by subscription.
Which Google Cloud product manages, secures and monetizes APIs?
Apigee API Management.
Topic 5 of 5 in Modernizing Infrastructure and Applications with Google Cloud
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