Feat: pagination

[martinjagodic]

Add opt-in pagination to collections. Works with filtering and sorting, turns off when grouping. Basic tests added.

[Copilot]

Pull Request Overview

This pull request implements pagination functionality for the Decap CMS, allowing collections to display entries in pages rather than loading all entries at once. The implementation supports both client-side and server-side pagination.

Key Changes:

• Added pagination configuration options at both global and collection levels (enabled flag and per_page setting)
• Implemented pagination state management in Redux with page size, current page, and total count tracking
• Modified backend implementations to support optional pagination parameters
• Created pagination UI component with navigation controls
• Added client-side pagination support for filtered/sorted entries

Reviewed Changes

Copilot reviewed 24 out of 24 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
packages/decap-server/src/middlewares/types.ts	Added optional pagination options to EntriesByFolderParams
packages/decap-server/src/middlewares/localGit/index.ts	Implemented server-side pagination with cursor metadata
packages/decap-server/src/middlewares/localFs/index.ts	Implemented server-side pagination with cursor metadata
packages/decap-server/src/middlewares/joi/index.ts	Added Joi validation schema for pagination options
packages/decap-cms-locales/src/en/index.js	Added English translations for pagination UI
packages/decap-cms-lib-util/src/implementation.ts	Updated Implementation interface to include pagination options
packages/decap-cms-core/src/types/redux.ts	Added pagination-related types and state definitions
packages/decap-cms-core/src/reducers/entries.ts	Implemented pagination state management and selectors
packages/decap-cms-core/src/reducers/tests/entries.spec.js	Added comprehensive pagination test cases
packages/decap-cms-core/src/lib/pagination.ts	Created utility functions for pagination configuration
packages/decap-cms-core/src/lib/immutableHelpers.ts	Added helpers for working with Immutable.js objects
packages/decap-cms-core/src/lib/entryHelpers.ts	Added helpers for filtering, sorting, and grouping entries
packages/decap-cms-core/src/components/Collection/Entries/Pagination.js	Created pagination UI component
packages/decap-cms-core/src/components/Collection/Entries/*	Integrated pagination into entry listing components
packages/decap-cms-core/src/backend.ts	Added pagination support to backend entry loading
packages/decap-cms-core/src/actions/entries.ts	Implemented pagination actions and updated filter/sort logic
packages/decap-cms-backend-test/src/implementation.ts	Updated test backend to support pagination
packages/decap-cms-backend-proxy/src/implementation.ts	Updated proxy backend to pass pagination options
packages/decap-cms-backend-github/src/implementation.tsx	Implemented pagination for GitHub backend
packages/decap-cms-backend-git-gateway/src/implementation.ts	Updated git-gateway to pass pagination options
dev-test/config.yml	Added example pagination configuration

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[Copilot]

The map.setIn operation on line 270 does not actually mutate the map. It returns a new map that is not assigned back. Within a withMutations block, you must reassign the result or use a single chained operation. This will cause the pagination state to not be updated properly. Change to: const updated = existingPagination.merge({ currentPage, totalCount, pageSize }); map.setIn(['pagination', collection], updated);

Suggested change

	map.setIn(
	['pagination', collection],
	existingPagination.merge({ currentPage, totalCount, pageSize }),
	);
	const updated = existingPagination.merge({ currentPage, totalCount, pageSize });
	map.setIn(['pagination', collection], updated);

[Copilot]

Division by zero is possible if pageSize is 0. Although the default is 10, the function accepts a pageSize parameter that could be 0 or negative. Add validation: if (pageSize <= 0) throw new Error('pageSize must be positive'); at the start of the getCursor function.

Suggested change

	) {
	) {
	if (pageSize <= 0) {
	throw new Error('pageSize must be positive');
	}

[Copilot]

The logic is incorrect. entries.slice((page - 1) * pageSize) already slices to the start of the desired page. Calling take(..., pageSize) on the result will work, but it's redundant. The correct implementation should be: entries.slice((page - 1) * pageSize, page * pageSize) to get exactly one page of results.

Suggested change

	const ret = usePagination ? take(entries.slice((page - 1) * pageSize), pageSize) : entries;
	const ret = usePagination ? entries.slice((page - 1) * pageSize, page * pageSize) : entries;

[Copilot]

This check is too weak and will incorrectly identify any object with a get method as an Immutable Map (e.g., a plain JavaScript Map or a custom object). Use a more specific check like: return obj !== null && typeof obj === 'object' && 'toJS' in obj && typeof (obj as any).toJS === 'function' or check for Immutable's type using Map.isMap(obj) from the 'immutable' package.

Suggested change

	/**
	* Type guard to check if an object is an Immutable.js Map
	*/
	export function isImmutableMap(obj: unknown): boolean {
	return (
	typeof obj === 'object' && obj !== null && typeof (obj as { get?: unknown }).get === 'function'
	);
	import { Map } from 'immutable';
	/**
	* Type guard to check if an object is an Immutable.js Map
	*/
	export function isImmutableMap(obj: unknown): boolean {
	return Map.isMap(obj);

[Copilot]

If totalCount is 0, startEntry will be 1, which is incorrect. The displayed text will say 'Showing 1-0 of 0'. Add a check: const startEntry = totalCount === 0 ? 0 : (currentPage - 1) * pageSize + 1;

Suggested change

	const startEntry = (currentPage - 1) * pageSize + 1;
	const endEntry = Math.min(currentPage * pageSize, totalCount);
	const startEntry = totalCount === 0 ? 0 : (currentPage - 1) * pageSize + 1;
	const endEntry = totalCount === 0 ? 0 : Math.min(currentPage * pageSize, totalCount);

[Copilot]

Variable 'obj' is of type date, object or regular expression, but it is compared to an expression of type null.