cursor

README

Cursor

Cursor is a generic implementation of the Relay Cursor Connections Specification. It is a simple library that can be used to paginate any list of items.

Installation

Simply run the following command to get the package and start using it:

go get github.com/asger-noer/go-cursor

Usage

You can create a new connection by providing a list of items and a cursor function that can be used to get the cursor for each item. You can also provide a list of arguments to the connection to specify the pagination.

args := []cursor.Argument{
	cursor.First(10),
	cursor.After("MQ=="),
}

// Create a new connection with the list of users
cur, err := cursor.New(users, userCursor, args...)
if err != nil {
	// Handle error
}

// pageinfo contains information about the current page
pageinfo := cur.PageInfo()

// Edges contains the list of items in the current page
edges := cur.Edges() {

Documentation

Index

• Variables
• type Argument
  • func After(after *string) Argument
  • func Before(before *string) Argument
  • func First(first *int) Argument
  • func Last(last *int) Argument
• type Connection
  • func New[T any](nodes []T, cursor func(T) string, args ...Argument) (Connection[T], error)
  • func (p *Connection[T]) Edges() []Edge[T]
  • func (p *Connection[T]) PageInfo() PageInfo
• type Edge
  • func (e Edge[T]) Cursor() string
  • func (e Edge[T]) Node() T
• type Edges
  • func (e Edges[T]) Nodes() []T
• type PageInfo
  • func (p *PageInfo) EndCursor() *string
  • func (p *PageInfo) HasNextPage() bool
  • func (p *PageInfo) HasPreviousPage() bool
  • func (p *PageInfo) StartCursor() *string

Variables

var (
	ErrConflictingArguments = errors.New("first and last cannot be used together")
	ErrInvalidFirst         = errors.New("first argument must be a non-negative integer")
	ErrInvalidLast          = errors.New("last argument must be a non-negative integer")
)

Types

type Argument

type Argument func(*arguments) error

func After

func After(after *string) Argument

After sets the after option for the connection.

func Before

func Before(before *string) Argument

Before sets the before option for the connection.

func First

func First(first *int) Argument

First sets the first option for the connection.

func Last

func Last(last *int) Argument

Last sets the last option for the connection.

type Connection

type Connection[T any] struct {
	// contains filtered or unexported fields
}

Connection is a generic connection type that is used to paginate results.

func New

func New[T any](nodes []T, cursor func(T) string, args ...Argument) (Connection[T], error)

New creates a new Pages object. The pages object is used to paginate

func (*Connection[T]) Edges

func (p *Connection[T]) Edges() []Edge[T]

Edges returns the edges for the connection.

func (*Connection[T]) PageInfo

func (p *Connection[T]) PageInfo() PageInfo

PageInfo returns the page info for the connection.

type Edge

type Edge[T any] struct {
	// contains filtered or unexported fields
}

Edge is a generic type that is used to define the edges for a connection in at paginated result. The Edge interface is used to define the the cursor that is used to paginate the nodes and the node itself.

func (Edge[T]) Cursor

func (e Edge[T]) Cursor() string

func (Edge[T]) Node

func (e Edge[T]) Node() T

type Edges

type Edges[T any] []Edge[T]

func (Edges[T]) Nodes

func (e Edges[T]) Nodes() []T

type PageInfo

type PageInfo struct {
	// contains filtered or unexported fields
}

func (*PageInfo) EndCursor

func (p *PageInfo) EndCursor() *string

EndCursor returns the end cursor for the connection.

func (*PageInfo) HasNextPage

func (p *PageInfo) HasNextPage() bool

HasNextPage returns true if there is a next page.

func (*PageInfo) HasPreviousPage

func (p *PageInfo) HasPreviousPage() bool

HasPreviousPage returns true if there is a previous page.

func (*PageInfo) StartCursor

func (p *PageInfo) StartCursor() *string

StartCursor returns the start cursor for the connection.