GraphQL is a language for APIs that enables you to query and manipulate data easily through an intuitive and flexible syntax.

GraphQL is an open-source data query and manipulation language for APIs.

GraphQL was developed internally by Facebook in 2012 before being publicly released in 2015.

It is used in many server-side languages like Java, Node, Ruby, Python, PHP, Go, and obviously dotnet too. And APIs created using GraphQL can easily accessible by almost languages like JavaScript, Android, Swift, Python, PHP, Java, and dotnet.

In a GraphQL request, you specify how to structure the data when it’s returned by the server. This makes it possible for you to query only the data you need, in the format you need. This results in better network utilization and performance, especially on mobile devices.

The course outline includes:

• Introduction to GraphQL. And understood how it’s different from RESTful APIs.

• Create basic GraphQL queries. As well as with Arguments and aliases.

• Using fragments and inline fragments on the type to select specific fields.

• Using variables for passing data via query variable, and directives to obtain fields based on condition.

• Use paging to retrieve data as page wise and with sorting order.

• Understood what schema is and learn about each type supported by GraphQL.

• Use of Introspection for obtaining schema or type related details.

• Create a server-side project with Entity Framework core and GraphQL dotnet library.

• Use mutation for insert, update, or delete operation.

• Using subscription for creating an event stream.

• Implement Authentication for queries based on JWT Identity.

• Validation of query and Exception handing from the server-side.

• And executing queries and mutations from client-side project using C#.