7 p.m.
OK folks, below is the contents of this gist https://gist.github.com/4531575. I may have
missed a number of things, gotten too specific in places or not specific enough in others.
This should hopefully get a good discussion going on how we want to handle paging across
all of the client libraries. Let's keep all comments on the list and not the gist as
much as possible to avoid breaking up the conversation.
Below is a pipe configuration showing the different paging options. Defaults are just
suggestions and are up for discussion as much as the rest of it
var pagedPipe = AeroGear.Pipeline({
name: "pager",
settings: {
paged: {String}, // Default is "headers", can also be
"content", or undefined for no paging
pageConfig: { // Only required if paged is not undefined
// which page, header default is "AG-Paging-Offset", content
default is "paging.offset"
offset: {String},
offsetVal: {Number}, // Default 0 for first page
// items per page, header default is "AG-Paging-Limit", content
default is "paging.limit"
limit: {String},
limitVal: {Number}, // Default 5 items per page
// total number of items, header default is "AG-Paging-Total",
content default is "paging.total"
total: {String},
// link to next page, default in both cases is undefined
next: {String},
// link to previous page, default in both cases is undefined
prev: {String}
}
}
}).pipes.pager;
Getter/Setter methods should be provided for getting and updating the offsetVal and
limitVal defaults
var defaultOffset = pagedPipe.getOffsetVal();
pagedPipe.setOffsetVal( defaultOffset + 1 ); // by default the second page would be
returned
var defaultLimit = pagedPipe.getLimitVal();
pagedPipe.setLimitVal( defaultLimit + 5 ); // by default, 10 items would be returned
per page
## read()
By default, a read() against a paged pipe will return the first page based on the default
offsetVal and limitVal. We could possible add an option that doesn't effect unpaged
pipes but on a paged pipe, it can be used to turn off paging for that read() and get all
data
// Get first page
pagedPipe.read({success callback handles data});
// Get all data from paged pipe
pagedPipe.read({
page: false,
success: handle the data
});
To avoid code duplication, **next**, **prev**, **first** and **last** pages can be
retrieved by passing an option to the read method of a paged pipe since other than some
paging housekeeping, the code would be the same. We can also use that same option as above
that was used to get all data from a paged pipe. One question, when requesting prev from
first page or next from last page, should it throw an error that needs to be handled or
just return and empty data set? I see advantages and disadvantages of both.
// Get next page
pagedPipe.read({
page: "next",
success: handle the data
});
// Get previous page
pagedPipe.read({
page: "prev",
success: handle the data
});
// Get first page
pagedPipe.read({
page: "first",
success: handle the data
});
// Get last page
pagedPipe.read({
page: "last",
success: handle the data
});