1. What’s Your Type?
Understanding API Types and Choosing
the Right One
Iddo Gino, Founder & CEO, RapidAPI

2. About RapidAPI
● World’s Largest API Marketplace
○ 1 Million Developers
○ >10,000 APIs
○ Billions of API Calls
● Founded in 2015
● Based in San Francisco & Tel Aviv
● Backed by:

3. Agenda
Proliferation of APIs1
2 APIs in the Enterprise
5 Questions (and Answers)
4 Next-generation Platform for All APIs
3 API Types – From REST to Kafka

4. Proliferation of APIs
● Developers are increasingly utilizing APIs to develop new applications and software
● API Economy is predicted to grow to $2.2 Trillion dollars
● Already yielded multiple unicorns:
Ovum, “Realizing the Business Value of APIs,” October 2014
Google Searches for “Rest API”, 2004-2019
Acquired - $3B Public - $15B Private - $35B
Acquired - $800M Public - $18B Private - $1.1B

5. Proliferation of APIs – Grows as Company Scales
16
29
52
82
92
160
307
Less than 10 10-50 51-100 101-500 501-1,000 1,001-5,000 5,001-10,000
Organization Size
How many APIs in your organization?
RapidAPI API Survey, 2019

6. 3.2%
5.6%
8.8% 8.8%
10.4%
8.0%
10.8%
12.4%
8.0% 8.0%
7.2%
8.8%
How many APIs in your organization?
Imperva API Survey, 2018
APIs in the Enterprise
● Developers are increasingly utilizing APIs to
develop new applications and software
● 50% of organizations have more than 300
APIs
● Many have thousands of APIs
● Many organizations are enabling customers
and partners to leverage their APIs

7. APIs used in the Enterprise
Continuous Process
• Powering integrations with
select partners & customers
• Exposed on a per-need basis
• Requires direct business
agreement / relationship
Partner APIs
• Internal services created
by development team
• Used to build applications
and services
• Not exposed externally
Internal APIs
• Used by developers to speed
up development
• May be integrated on an ad-
hoc basis by developers
• Used for basic infrastructure
and functionality
Public APIs

8. API Types Explained

9. APIs - Many Shapes and Forms
● Technology and standards landscape in
APIs is shifting
● API standards are diverging – more
specialized standards are introduced
● Starting to adopt event driven
architecture
● Makes API discovery & integration
more difficult
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
REST SOAP Webhooks Severless & FaaS GraphQL gRPC
API Technology Adoption
Using in Production In POC Investigating Aware But Not Using Unfamiliar
RapidAPI API Survey, 2019

10. Older Mature Cutting Edge
RPC
SOAP
Webhooks
REST
Pub/Sub
GraphQL
Protobuffs
gRPC
Kafka
API Types Maturity Scale
1960s
1990s
2000s 2010s

11. API Diversity
APIs / microservices play varied roles in applications
● Data retrieval
● CRUD
● Job executions (encoding, sending, etc)
● Conversion
Thus the technical requirements vary
● Data exploration
● Low latency / low overhead
● Load management / async behavior
There isn’t a one size fit all…

12. ● REST APIs are used to call resources and
allow software to communicate based on
standardized principles, properties, and
constraints
● Uses HTTP requests to GET, PUT, POST and
DELETE data
Who uses it
REST (Representative State Transfer)
GraphQL
Kafka Webhooks PUB/SUB
RPC gRPC Protobufs
SOAPSOAPREST

13. ● REST operates on a simple
request/response system
● Response returns relevant data, which
can be formatted as JSON, XML, plain
text, images etc.
● RESTful APIs can be designed with
different endpoints that return
different data
● Accessing multiple endpoints requires
multiple calls
How REST Works
REST
REST
RESTClient Database

14. ● Relies on XML to make requests and
receive responses
● Ideal for transactions that involve multiple
calls or applications where security is the
main consideration
● Less complex – requires less coding in the
app layer for transactions, security and
other functions
Who uses it
SOAP (Simple Object Protocol)
REST
GraphQL
Kafka Webhooks PUB/SUB
RPC gRPC Protobufs
REST SOAP

15. When to use REST vs. SOAP
Familiarity – Dev team has used, short learning curve
Interoperability – Most platforms/frameworks interface
with REST
Flexibility – REST APIs can handle multiple types of calls
and return different data formats.
Performance – Recommend for higher loads and
processes.
Development efficiencies – Rest APIs are reusable; can
build independent microservices that work
independently of one another
REST
Legacy – many older platforms will come with SOAP based
APIs
Extensibility – Allows for extensions that introduce powerful
features (Windows Server)
Neutrality – Operates over a wide range of protocols
Transactional reliability – Reliable for financial transactions
Independence – Compatible with nearly any programming
language
Standardization – Designed rules and specs
SOAP

16. ● Query language developed by Facebook
that lets the client define the structure of
the data required
○ Request data from multiple sources in a
single request
○ Control exactly what information your
application receives in the response
Who uses it
GraphQL
REST
Kafka Webhooks PUB/SUB
RPC gRPC Protobufs
SOAPSOAP GraphQL

17. ● Pre-defined schema is what allows the
client to specify the exact shape of
data returned
● Ability to define exact request and
response structure cuts down on the
resources and bandwidth required
● Returns only the desired data in the
response
How GraphQL Works
REST

18. Easy of Use – Aggregates data from multiple
sources into one convenient API
When to Use GraphQL
REST
Kafka Webhooks PUB/SUB
RPC gRPC Protobufs
SOAPSOAP GraphQL
Performance – combine queries & omit
unnecessary data
Development efficiencies – decouples front end
and backend development
Ease of onboarding – self documenting APIs

19. ● Stream-processing software platform
developed by LinkedIn
● Popular with large enterprise due to the
unique ability to handle and process data
streams and ingest/move large amounts of
data quickly
● 5 core Kafka-based APIs: Producer,
Consumer, Streams, Connector, Admin
Who uses it
Kafka (async / queue based APIs)
GraphQL
Webhooks PUB/SUB
RPC gRPC Protobufs
SOAPSOAPREST
Kafka

20. How Queue Based APIs Work
Queue
Web Client
Encoding
Service
Encode
Request
Encode
Request
Confirmation
Encode
Request

21. Async Processing– Processes / flows don’t
happen in real-time
High Performance – Due to low latency, Kafka
can handle more messages of high
volume/velocity
Scalable – Distributed system that can be
scaled independently
Reliable – Record processes and handle failures
gracefully
When to Use Kafka
REST
Webhooks PUB/SUB
RPC gRPC Protobufs
SOAPSOAP GraphQL
Kafka

22. ● Webhook – Method for server-side app to notify
client-side app that an event has occurred
Other API Types – Webhooks and Pub/Sub
Webhooks
Pub/Sub
● Pub/Sub – Asynchronous communication method
where messages are exchanged between
applications without knowing the sender or
recipient
When to Use: Real-time events that require you
to send data from one application to another
When to use: For event-driven architectures,
balancing workloads or data streaming

23. Other API Types – RPC, gRPC, and Protobufs
Open sourced version of RPC
introduced by Google (uses
HTTP/2)
Use case: Used for low
latency, scalable, distributed
systems (i.e. mobile
application development)
Uses a client-server model to
enable one program to request
a service from another program
over a network
Use case: RPC is used to call
other processes on a remote
system with the same
Google’s language-neutral,
platform-neutral, extensible
mechanism for serializing
structured data
Use case: Smaller and faster than
XML, used for RPC systems and
storage of data.
RPC gRPC Protobufs

24. A Heterogeneous Environment
Transactions
Service
RPC
Account
Balances
SOAP
User IDs
REST
International
Wires
Kafka
Product
Information
GraphQL
Loan
Approvals
REST
Credit Score
Checks
REST
Facebook
Login
GraphQL
Credit Card
Network
REST
OCR Service
REST
On-premise Private Cloud 3rd Party

25. A Homogenous Environment
Transactions
Service
RPC
Account
Balances
SOAP
User IDs
REST
International
Wires
Kafka
Product
Information
GraphQL
Loan
Approvals
REST
Credit Score
Checks
REST
Facebook
Login
GraphQL
Credit Card
Network
RE
OCR Service
REST
API Hub

26. Next-generation API Platform

27. Microservices: 68% are Using or Investigating
● Internal APIs = microservices & internal systems
● Hundreds of internal APIs VS tens of external
APIs
● Most APIs start as internal and graduate to be
public facing
29%
15%
24%
30%
Using microservices in
production
Using microservices in
development
Investigating
microservices
Other (2%)
Not using
microservices
Ngnix Survey, 2015

28. APIs – Start Inside Out
Internal APIs.
Used by: internal developers.
Used for: creating new products and integrations.
Partner APIs.
Used by: existing customers & partners.
Used for: deep integrations, dashboarding, reports.
Public APIs.
Used by: any 3rd party developer (self-service).
Used for: new applications & services.

29. Internal APIs – Unlocking Innovation
● To innovate, developers need access to data and
functionality
● That data and functionality is siloed behind APIs
● Organizing internal APIs
○ Makes data and functionality more accessible
○ Enables developers to innovate
○ Speeds up time to market
New Digital Experience
API API API API

30. Enterprise API Hub
Enterprise
API Hub
API Creators
Publish APIs
Internal Developers
Discover & Connect
to APIs
External Developers
Governance Team
Manage APIs

32. API Platform
Publish API Documentation
CI/CD & Gateway Integration
Access & Visibility Control
Support for All API Types
Monetization

33. API Platform
API Search
Tagging and Filtering
Interactive API Testing
Code Snippets for Integration
Monitoring & Analytics

34. API Platform Control API Visibility
Define API Readiness Requirements
Ensure Compliance
Track API Usage

36. RapidAPI

37. RapidAPI – Powering the API Economy
Discover APIs
Developers use RapidAPI to search for APIs, test APIs and compare them based on latency,
uptime and popularity.
Connect to APIs
RapidAPI gives developers a single SDK and access point to connect to any API. Developers
pay for APIs via RapidAPI.
Monitor & Analyze APIs
Developers use RapidAPI dashboard to monitor API performance and switch APIs seamlessly.

38. RapidAPI – API Discovery
● Search through a catalog of over
10,000 APIs.
● Instantly see API metrics, including
uptime, latency and popularity.
● Powerful API search including API
tags and metadata.

39. RapidAPI – API Connection
● See all API endpoints &
their parameters.
● Test any API directly from
the website.
● Copy code snippets to
embed API connection
into your application.

40. RapidAPI – API Consumption Analytics
● View analytics on API
call volume, latency and
error rate.
● Identify issues by digging
into log level
information on API calls.

41. RapidAPI – API Monetization
● Create billing plans
● Automatically invoice users
● Bill per object
● Rate limiting by plan
● Limit endpoint by plan
● Require DocuSign Signature
● Built-in credit card, ACH support

42. Built for Every API

43. REST / SOAP

44. GraphQL

45. Kafka

46. Conclusion
● Determine how the API works, when to use it, and if it is at a
point in maturity that makes sense for your application
● Try out new API Types and narrow down the right one that works
for your project.
● With the proliferation of APIs, companies needs a centralized API
Platform that is runtime agnostic, supports internal and external
APIs, and accommodates multiple API types
● The ”right” API type depends on your project goals