Cursor-based pagination queries for Sequelize models. Some motivation and background.
With npm:
npm install sequelize-cursor-pagination
With Yarn:
yarn add sequelize-cursor-pagination
Define a static pagination method for a Sequelize model with the makePaginate
function:
const { makePaginate } = require('sequelize-cursor-pagination');
const Counter = sequelize.define('counter', {
id: { type: Sequelize.INTEGER, primaryKey: true, autoIncrement: true },
value: Sequelize.INTEGER,
});
Counter.paginate = makePaginate(Counter);
The first argument of the makePaginate
function is the model class. The function also has a second, optional argument, which is the options object. The options object has the following properties:
primaryKeyField
: The primary key field of the model. With a composite primary key, provide an array containing the keys, for example['key1', 'key2']
. If not provided, the primary key is resolved from the model's attributes (attributes withprimaryKey: true
). This is the desired behavior in most cases.omitPrimaryKeyFromOrder
: By default, the primary key is automatically included in the order if it is missing. Setting this option totrue
will override this behavior. The default value isfalse
.
Call the paginate
method:
const result = await Counter.paginate({
where: { value: { [Op.gt]: 2 } },
limit: 10,
});
The paginate
method returns a promise, which resolves an object with the following properties:
edges
: An array containing the results of the query. Each item in the array contains an object with the following properties:node
: The model instancecursor
: Cursor for the model instance
totalCount
: The total numbers rows matching the querypageInfo
: An object containing the pagination related data with the following properties:startCursor
: The cursor for the first node in the result edgesendCursor
: The cursor for the last node in the result edgeshasNextPage
: A boolean that indicates whether there are edges after theendCursor
(false
indicates that there are no more edges after theendCursor
)hasPreviousPage
: A boolean that indicates whether there are edges before thestartCursor
(false
indicates that there are no more edges before thestartCursor
)
The paginate
method has the following options:
after
: The cursor that indicates after which edge the next set of edges should be fetchedbefore
: The cursor that indicates before which edge next set of edges should be fetchedlimit
: The maximum number of edges returned
Other options passed to the paginate
method will be directly passed to the model's findAll
method.
order
option format only supports the ['field']
and ['field', 'DESC']
variations (field name and the optional order direction). For example, ordering by an associated model's field won't work.
The examples use the Counter
model defined above.
Fetch the first 20
edges ordered by the id
field (the primaryKeyField
field) in ascending order:
const result = await Counter.paginate({
limit: 20,
});
First, fetch the first 10
edges ordered by the value
field in a descending order. Second, fetch the first 10
edges after the endCursor
. Third, fetch the last 10
edges before startCursor
:
const firstResult = await Counter.paginate({
order: [['value', 'DESC']],
limit: 10,
});
const secondResult = await Counter.paginate({
order: [['value', 'DESC']],
limit: 10,
after: firstResult.pageInfo.endCursor,
});
const thirdResult = await Counter.paginate({
order: [['value', 'DESC']],
limit: 10,
before: secondResult.pageInfo.startCursor,
});
The library is written in TypeScript, so types are on the house!
If you are using a static method like in the previous examples, just declare the method on your model class:
import {
PaginateOptions,
PaginationConnection,
makePaginate,
} from 'sequelize-cursor-pagination';
export class Counter extends Model<
InferAttributes<Counter>,
InferCreationAttributes<Counter>
> {
declare id: CreationOptional<number>;
declare value: number;
declare static paginate: (
options: PaginateOptions<Counter>,
) => Promise<PaginationConnection<Counter>>;
}
// ...
Counter.paginate = makePaginate(Counter);
The withPagination
function is deprecated starting from version 3, but the migration is fairly simple.
Version 2:
const withPagination = require('sequelize-cursor-pagination');
const Counter = sequelize.define('counter', {
id: { type: Sequelize.INTEGER, primaryKey: true, autoIncrement: true },
value: Sequelize.INTEGER,
});
withPagination({ primaryKeyField: 'id' })(Counter);
Version 3 onwards:
const { makePaginate } = require('sequelize-cursor-pagination');
const Counter = sequelize.define('counter', {
id: { type: Sequelize.INTEGER, primaryKey: true, autoIncrement: true },
value: Sequelize.INTEGER,
});
Counter.paginate = makePaginate(Counter);