GraphQL vs. REST API: What’s the difference?

As
the
conduits
through
which
software
components
interact
and
data
flows
across
the
internet,
APIs
are
the
lifeblood
of
contemporary
web
services.
API
technologies
like
SOAP
(a
web
services
messaging
protocol),
REST
(an
architectural
style)
and

GraphQL
(a
programming
language
and
tool)
simplify
software
development
by
enabling
third-party
data
and
services
integration.
APIs
also
enable
companies
to
offer
secure
service
functions
and
data
exchange
to
employees,
business
partners,
and
users.

Despite
the
many
types
of

APIs,
debates
about
two
major
paradigms
have
dominated
the
conversation
in
recent
years:

REST
(representational
state
transfer)
and

GraphQL.
Both
offer
a
range
of
benefits
and
thus
are
deployed
for
networking
projects
across
the
globe.
However,
they
differ
significantly
in
how
they
manage
data
traffic.
Here,
we
dissect
those
differences
and
discuss
how
businesses
can
use
REST
and
GraphQL
APIs
to
optimize
their
networks.

What
are
REST
and
GraphQL
APIs?

An
understanding
of
REST
and
GraphQL
APIs
individually
is
necessary
for
a
comparison
of
the
two.

REST

Developed
in
the
early
2000s,
REST
is
a
structured
architectural
style
for
networked
hypermedia
applications,
which
is
designed
to
use
a
stateless,
client/server,
cacheable
communication
protocol.
REST
APIs,
also
called
RESTful
APIs,
are
the
drivers
of
REST
architectures.

REST
APIs
use
unique
resource
identifiers
(URIs)
to
address
resources.
REST
APIs
work
by
having
different
endpoints
perform
CRUD
(“create,”
“read,”
“update”
and
“delete”)
operations
for
network
resources.
They
rely
on
a
predefined
data
format—called
a
media
type
or
MIME
type—to
determine
the
shape
and
size
of
resources
they
provide
to
clients.
The
most
common
formats
are
JSON
and
XML
(and
sometimes
HTML
or
plain
text). 

When
the
client
requests
a
resource,
the
server
processes
the
query
and
returns
all
the
data
that
is
associated
with
that
resource.
The
response
includes
HTTP
response
codes
like
“200
OK”
(for
successful
REST
requests)
and
“404
Not
Found”
(for
resources
that
don’t
exist).

GraphQL

GraphQL
is
a
query
language
and
API
runtime
that
Facebook
developed
internally
in
2012
before
it
became

open
source
in
2015.

GraphQL
is
defined
by
API
schema
written
in
the
GraphQL
schema
definition
language.
Each
schema
specifies
the
types
of
data
the
user
can
query
or
modify,
and
the
relationships
between
the
types.
A
resolver
backs
each
field
in
a
schema.
The
resolver
provides
instructions
for
turning
GraphQL
queries,
mutations,
and
subscriptions
into
data,
and
retrieves
data
from
databases,
cloud
services,
and
other
sources.
Resolvers
also
provide
data
format
specifications
and
enable
the
system
to
stitch
together
data
from
various
sources.

Unlike
REST,
which
typically
uses
multiple
endpoints
to
fetch
data
and
perform
network
operations,
GraphQL
exposes
data
models
by
using
a
single
endpoint
through
which
clients
send
GraphQL
requests,
regardless
of
what
they’re
asking
for.
The
API
then
accesses
resource
properties—and
follows
the
references
between
resources—to
get
the
client
all
the
data
they
need
from
a
single
query
to
the
GraphQL
server. 

Both
GraphQL
and
REST
APIs
are
resource-based
data
interchanges
that
use
HTTP
methods
(like
PUT
and
GET
requests)
that
dictate
which
operations
a
client
can
perform.
However,
key
differences
exist
between
them
that
explain
not
only
the
proliferation
of
GraphQL
but
also
why
RESTful
systems
have
such
staying
power.

Differences
between
GraphQL
and
REST
APIs

GraphQL
offers
an
efficient,
more
flexible
addition
to
REST;
GraphQL
APIs
are
often
viewed
as
an
upgrade
from
RESTful
environments,
especially
given
their
ability
to
facilitate
collaboration
between
front-end
and
back-end
teams.
GraphQL
provides
a
logical
next
step
in
an
organization’s
API
journey,
helping
fix
issues
that
are
often
encountered
with
REST.

However,
REST
was
long
the
standard
for
API
architectures,
and
many
developers
and
architects
still
rely
on
RESTful
configurations
to
manage
their
IT
networks.
As
such,
understanding
the
distinctions
between
the
two
is
integral
to
any
organization’s
IT
management
strategy. 

REST
and
GraphQL
APIs
differ
in
how
they
manage:

Data
retrieval

Because
REST
relies
on
multiple
endpoints
and
stateless
interactions—where
every
API
request
is
processed
as
a
new
query,
independent
of
any
others—clients
receive
every
piece
of
data
that
is
associated
with
a
resource.
If
a
client
needs
only
a
subset
of
the
data,
it
still
receives
all
the
data
(over-fetching).
And
if
the
client
needs
data
that
spans
multiple
resources,
a
RESTful
system
often
makes
the
client
query
each
resource
separately
to
compensate
for
inadequate
data
retrieval
from
the
initial
request
(under-fetching).
GraphQL
APIs
use
a
single
GraphQL
endpoint
to
give
clients
a
precise,
comprehensive
data
response
in
a
one
round
trip
from
a
single
request,
eliminating
over-
and
under-fetching
issues.

Versioning

In
a
REST
architecture,
teams
must
version
APIs
to
modify
data
structures,
and
prevent
system
errors
and
service
disruptions
for
the
end
user.
In
other
words,
developers
must
create
a
new
endpoint
every
time
they
make
changes,
creating
multiple
API
versions
and
potentially
complicating
maintenance.
GraphQL
reduces
the
need
for
versioning
because
clients
can
specify
their
data
requirements
in
the
query.
The
addition
of
new
fields
to
the
server
does
not
affect
clients
without
a
need
for
those
fields.
Conversely,
if
fields
are
deprecated,
clients
can
continue
to
request
them
until
queries
are
updated.

Error
handling

REST
APIs

should
use
HTTP
status
codes
to
indicate
the
status
or
success
of
a
request,
and
each
status
code
has
a
specific
meaning.
A
successful
HTTP
request
returns
a
200
status
code,
while
a
client
error
might
return
a
400
status
code
and
a
server
error
might
return
a
500
status
code.

At
first
glance,
this
approach
to
status
reporting
seems
more
straightforward,
but
HTTP
status
codes
are
often
more
useful
to
web
users
than
to
the
APIs
themselves,
especially
in
the
case
of
errors.
REST
does
not
have
a
specification
for
errors,
so
API
errors
can
appear
as
transport
errors
or
don’t
appear
with
the
status
code
at
all.
This
dynamic
can
force
personnel
to
read
through
the
status
documentation
to
understand
what
errors
mean
or
even
how
errors
are
communicated
within
the
infrastructure.

With
GraphQL
APIs,
every
request—regardless
of
whether
it
resulted
in
an
error—returns
a
200
OK
status
code
because
errors
aren’t
communicated
by
using
HTTP
status
codes
(except
for
transport
errors).
Instead,
the
system
communicates
errors
in
the
response
body
along
with
the
data,
so
clients
must
parse
through
the
data
payload
to
determine
if
the
request
was
successful.

That
said,
GraphQL
does
have
a
specification
for
errors,
so
API
errors
are
more
easily
distinguishable
from
transport
errors.
The
exact
nature
of
errors
appears
in
the
“errors”
entry
in
the
response
body,
which
can
make
GraphQL
APIs
preferable
to
build
against.

Real-time
data

REST
doesn’t
have
built-in
support
for
real-time
updates.
If
an
app
needs
real-time
functionality,
developers
usually
must
implement
techniques
like
long-polling
(where
the
client
repeatedly
polls
the
server
for
new
data)
and
server-sent
events,
which
can
add
complexity
to
the
application.

However,
GraphQL
includes
built-in
support
for
real-time
updates
through
subscriptions.
Subscriptions
maintain
a
steady
connection
to
the
server,
allowing
the
server
to
push
updates
to
the
client
whenever
specific
events
happen.

Tools
and
environment

The
REST
environment
is
well
established,
with
a
wide
range
of
tools,
libraries,
and
frameworks
available
to
developers.
Working
with
REST
APIs
nonetheless
requires
teams
to
navigate
several
endpoints
and
understand
the
unique
conventions
and
patterns
of
each
API.

GraphQL
APIs
are
relatively
new,
but
the
GraphQL
environment
has
grown
tremendously
since
its
introduction,
with
various
tools
and
libraries
available
for
both
server
and
client
development.
Tools
like
GraphiQL
and
GraphQL
Playground
provide
powerful,
in-browser,
integrated
development
environments
(IDEs)
for
exploring
and
testing
GraphQL
APIs.
Furthermore,
GraphQL
has
strong
support
for
code
generation,
which
can
simplify
client-side
development.

Caching

REST
APIs
rely
on
mechanisms
like
eTags
and
last-modified
headers
to
cache
API
calls.
While
effective,
these
caching
strategies
can
be
complex
to
implement
and
might
not
be
suitable
for
all
use
cases.

GraphQL
APIs
can
be
more
challenging
to
cache
due
to
the
dynamic
nature
of
the
queries.
However,
deploying
persisted
queries,
response
caching,
and
server-side
caching
can
mitigate
these
challenges
and
streamline
broader
caching
efforts
in
GraphQL
architectures.

When
to
use
GraphQL
and
REST
APIs

Neither
REST
nor
GraphQL
APIs
are
inherently
superior;
they’re
different
tools
that
are
suited
to
different
tasks. 

REST
is
generally
easier
to
implement
and
can
be
a
good
choice
when
a
straightforward,
cacheable
communication
protocol
with
stringent
access
controls
is
a
preferred
(for
public-facing
e-commerce
sites
like
Shopify
and
GitHub,
as
one
example).
Given
the
under-
and
over-fetching
risks,
REST
APIs
are
best
for:

• Businesses
  that
  use
  smaller
  apps
  with
  simpler
  data
  profiles
• Businesses
  with
  no
  complex
  data
  querying
  requirements
• Businesses
  where
  most
  of
  the
  client
  base
  uses
  data
  and
  operations
  in
  similar
  ways

GraphQL
APIs
enable
more
flexible,
efficient
data
fetching,
which
can
improve
system
performance
and
ease-of-use
for
developers.
These
features
make
GraphQL
especially
useful
for
building
APIs
in
complex
environments
with
rapidly
changing
front-end
requirements.
This
includes:

• Businesses
  with
  limited
  bandwidth,
  looking
  to
  limit
  calls
  and
  responses
• Businesses
  that
  want
  to
  combine
  data
  points
  at
  a
  one
  endpoint
• Businesses
  whose
  client
  requests
  vary
  significantly

Though
they
use
different
approaches,
both
GraphQL
and
REST
APIs
have
the
potential
to
greatly
enhance
network
scalability
and
server
performance. 

Take
control
of
your
API
environment
with
IBM
API
Connect

Regardless
of
whether
you
choose
to
deploy
REST
or
GraphQL
APIs—or
some
combination
of
the
two—your
business
can
benefit
from
a
wide
range
of
potential
applications,
including
implementations
in
various
programming
languages
(like
JavaScript)
and
integration
with

microservices
and

serverless
architectures. With

IBM
API
Connect,
you
can
use
both
API
types
to
optimize
your
IT
infrastructure.

IBM
API
Connect
is
a
full-lifecycle
API
management
solution
that
helps
you
create,
manage,
secure,
socialize
and
monetize
APIs,
and
promote
digital
transformation
across
data
centers
and
cloud
environments.
This
means
that
both
businesses
and
customers
can
power
digital
apps
and
spur
innovation
in
real
time.

With
API
Connect,
enterprises
can
help
ensure
they’re
operating
at
the
leading
edge
of
API
management,
which
will
prove
invaluable
in
a
computing
landscape
that
is
poised
to
grow
larger,
more
complex
and
more
competitive
over
time.

Explore
IBM
API
Connect

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