In this video we are going to learn API, gateway web socket, API, core concepts.
We can say that the main core concepts of web socket API are roots, integration and states.
So in a website API, the client and server can both send message to each other at any time and they
can.
Service can easily push data to connected user and devices, avoiding need to implement complex polling
mechanism.
So it is a collection of web socket roots and the root case that are integrated with the backend HTTP
and lambda functions or other services.
So if you look at the core concepts of web socket API, we can start with the root selection expression
around selection expression tiles API gateway which draw to call when a client send a message.
So API Gateway use the raw selection expression to determine which role to invoke when a client sends
a message.
When your API receives a adjacent message from a client, API, gateway evaluates the root selection
expression and select the row that match the result.
So another important core concept is roads API gateway use rods to expose integrations to the client
applications.
API Gateway evaluates the raw selection expression of our API at runtime to determine which raw to invoke
this incoming event.
So we have two types.
The first one is predefined route.
The second one is custom lots.
So in predefined roles we have connect, disconnect and default routes.
So the connect rod is triggered when a client connects our API.
The disconnect is triggered when either the server or the client close the connections so the default
rod is triggered.
If the rod selection expression can't be evaluated against the message, or if there is no matching
rod is found.
So for customers, in order to invoke a specific integration based on message content, we should create
a customer load.
When an incoming message contains a JSON property API gateway, use our API selection expression to
determine which route to invoke.
So when they evaluate route selection expression match a custom route API gateway invokes the integration
that we attach to the custom route.
So another core concept is attaching integrations.
In order to deploy an API, we must set up at least one route.
All the routes that we set up must have an integration attached.
So in order to set up the integrations, we should, we can select the mode as the integration type
for our routes.
So another important core concept is states.
States are independently configurable environment that are API can be deployed.
So we must deploy to a state for API configuration change to take effect.
We can edit stage the result environment such as development or production.
So now let's create a web socket API with using a measurement console.