elm-paginated/README.md
2018-01-22 17:02:21 -05:00

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A library for fetching data from paginated JSON REST APIs.
# Motivation
This library is built to handle fetching data from a JSON REST API
that paginates its results. It inspects response headers, and will
prepare subsequent requests when additional pages of results remain.
Given a JSON decoder for the data type returned in the paginated
collection, it will return a data structure containing the results
fetched, and a new request object for fetching additional records from
the next page if more are available.
It is expected that the paginated REST API will provide a link for the
next page of results in the `Link` header, e.g.:
Link: <https://api.example.com/search?q=abc&page=2>; rel="next"
Absence of a link with `rel="next"` in the response headers is assumed
to mean the final page of results has been reached.
# Example Usage
import Http
import Json.Decode exposing (string)
import Paginated exposing (Response(..))
type alias Model =
{ results : Maybe (List String) }
type Msg
= Search
| Results (Result Http.Error (List String))
update : Msg -> Model -> ( Model, Cmd Msg )
update msg model =
case msg of
Search ->
( model, doSearch )
Results results ->
( { model | results = Result.toMaybe results }
, Cmd.none
)
doSearch : Cmd Msg
doSearch =
Paginated.send Results <|
Paginated.get "http://example.com/search?q=abc" string