angel_paginate 1.0.0+2 angel_paginate: ^1.0.0+2 copied to clipboard
Platform-agnostic pagination library, with custom support for the Angel framework.
paginate #
Platform-agnostic pagination library, with custom support for the Angel framework.
Installation #
In your pubspec.yaml
file:
dependencies:
angel_paginate: ^1.0.0
Usage #
This library exports a Paginator<T>
, which can be used to efficiently produce
instances of PaginationResult<T>
. Pagination results, when serialized to JSON, look like
this:
{
"total" : 75,
"items_per_page" : 10,
"previous_page" : 3,
"current_page" : 4,
"next_page" : 5,
"start_index" : 30,
"end_index" : 39,
"data" : ["<items...>"]
}
Results can be parsed from Maps using the PaginationResult<T>.fromMap
constructor, and
serialized via their toJson()
method.
To create a paginator:
import 'package:angel_paginate/angel_paginate.dart';
main() {
var p = new Paginator(iterable);
// Get the current page (default: page 1)
var page = p.current;
print(page.total);
print(page.startIndex);
print(page.data); // The actual items on this page.
p.next(); // Advance a page
p.back(); // Back one page
p.goToPage(10); // Go to page number (1-based, not a 0-based index)
}
The entire Paginator API is documented, so check out the DartDocs.
Paginators by default cache paginations, to improve performance as you shift through pages. This can be especially helpful in a client-side application where your UX involves a fast response time, i.e. a search page.
Use With Angel #
Naturally, a library named angel_paginate
has special provisions for the
Angel framework.
In package:angel_paginate/server.dart
, a function called paginate
generates
pagination service hooks for you. If the result of a hooked service event is an Iterable
,
it will be paginated. This is convenient because it works with any data store, whether it
be MongoDB, RethinkDB, an in-memory store, or something else entirely.
configureServer(Angel app) {
var service = app.service('api/foo') as HookedService;
service.afterIndexed.listen(paginate(itemsPerPage: 10));
}
See test/server_test.dart
for examples of usage with Angel.
The pagination hook also allows you to provide a page
and/or $limit
in the query.
If the user provides a page
in the query, it will return a pagination of the given page.
Ex. http://mysite.com/api/todos?page=4
A $limit
can be used to override the itemsPerPage
set in the paginate
hook. If you
would like to set a maximum on the number of items per page, you can set maxItemsPerPage
in the paginate
call.
Ex. http://mysite.com/api/todos?$limit=25
You can use these pagination functions to provide powerful search experiences on your websites.
NOTE: If the paginated data is empty, expect start_index
and end_index
to both be -1
.