Using the Book Search Data API
The Google Book Search Data API allows client applications to view
and update Book Search content in the form of Google Data API feeds.
Your client application can use the Book Search Data API to issue
full-text searches for books and to retrieve standard book information,
ratings, and reviews. You can also access individual users'
library collections and
public reviews. Finally, your application can submit authenticated requests
to enable users to create and modify library collections, ratings, labels,
reviews, and other account-specific entities.
For more information on the Book Search Data API, please refer to the
official PHP
Developer's Guide on code.google.com.
Authenticating to the Book Search service
You can access both public and private feeds using the Book Search
Data API. Public feeds don't require any authentication, but they are
read-only. If you want to modify user libraries, submit reviews or
ratings, or add labels, then your client needs to authenticate before
requesting private feeds. It can authenticate using either of two
approaches: AuthSub proxy authentication or ClientLogin username/password
authentication. Please refer to the Authentication
section in the PHP Developer's Guide for more detail.
Searching for books
The Book Search Data API provides a number of feeds that list
collections of books.
The most common action is to retrieve a list of books that match a
search query. To do so you create a VolumeQuery object
and pass it to the Books::getVolumeFeed() method.
For example, to perform a keyword query, with a filter on
viewability to restrict the results to partial or full view books, use
the setMinViewability() and setQuery()
methods of the VolumeQuery object. The following code snippet
prints the title and viewability of all volumes whose metadata or text matches
the query term "domino":
newVolumeQuery();
$query->setQuery('domino');
$query->setMinViewability('partial_view');
$feed = $books->getVolumeFeed($query);
foreach ($feed as $entry) {
echo $entry->getVolumeId();
echo $entry->getTitle();
echo $entry->getViewability();
}
]]>
The Query class, and subclasses like
VolumeQuery, are responsible for constructing feed
URLs. The VolumeQuery shown above constructs a URL
equivalent to the following:
Note: Since Book Search results are
public, you can issue a Book Search query without authentication.
Here are some of the most common VolumeQuery
methods for setting search parameters:
setQuery(): Specifies a search
query term. Book Search searches all book metadata and full text for
books matching the term. Book metadata includes titles, keywords,
descriptions, author names, and subjects.
Note that any spaces, quotes or other punctuation in the parameter
value must be URL-escaped (Use a plus (+) for a
space). To search for an exact phrase, enclose the phrase in quotation marks.
For example, to search for books matching the phrase "spy plane", set
the q parameter to %22spy+plane%22.
You can also use any of the
advanced search operators supported by Book Search. For example,
jane+austen+-inauthor:austen returns matches that mention
(but are not authored by) Jane Austen.
setStartIndex(): Specifies
the index of the first matching result that should be included in the
result set. This parameter uses a one-based index, meaning the first
result is 1, the second result is 2 and so forth. This parameter works
in conjunction with the max-results
parameter to determine which results to return. For example, to
request the third set of 10 results—results 21-30—set
the start-index parameter to 21 and the
max-results parameter to 10.
Note: This isn't a general cursoring
mechanism. If you first send a query with
?start-index=1&max-results=10 and then send another
query with ?start-index=11&max-results=10, the
service cannot guarantee that the results are equivalent to
?start-index=1&max-results=20, because insertions and
deletions could have taken place in between the two queries.
setMaxResults():
Specifies the maximum number of results that should be included
in the result set. This parameter works in conjunction with the
start-index parameter to determine which
results to return. The default value of this parameter is
10 and the maximum value is 20.
setMinViewability(): Allows you to filter the results according
to the books' viewability
status. This parameter accepts one of three values:
'none' (the default, returning all matching books regardless of
viewability), 'partial_view' (returning only books
that the user can preview or view in their entirety), or
'full_view' (returning only books that the user can
view in their entirety).
Partner Co-Branded Search
Google Book Search provides Co-Branded
Search, which lets content partners provide full-text search of
their books from their own websites.
If you are a partner who wants to do Co-Branded Search using the
Book Search Data API, you may do so by modifying the feed
URL above to point to your Co-Branded Search implementation. if,
for example, a Co-Branded Search is available at the following
URL:
then you can obtain the same results using the Book Search Data
API at the following URL:
To specify an alternate URL when querying a volume feed, you can
provide an extra parameter to newVolumeQuery()
newVolumeQuery('http://www.google.com/books/p/PARTNER_COBRAND_ID');
]]>
For additional information or support, visit our
Partner help center.
Book collections and My Library
Google Book Search provides a number of user-specific
book collections, each of which has its own feed.
The most important collection is the user's My Library, which
represents the books the user would like to remember, organize, and
share with others. This is the collection the user sees when accessing
his or her My Library
page.
Retrieving books in a user's library
The following sections describe how to retrieve a list
of books from a user's library, with or without query
parameters.
You can query a Book Search public feed without authentication.
Retrieving all books in a user's library
To retrieve the user's books, send a query to the
My Library feed. To get the library of the authenticated
user, use me in place of USER_ID.
getUserLibraryFeed();
]]>
Note: The feed may not contain all of the user's books, because
there's a default limit on the number of results returned. For
more information, see the max-results query parameter in
Searching for books.
Searching for books in a user's library
Just as you can search across all books,
you can do a full-text search over just the books in a
user's library. To do this, just set the appropriate
paramters on the VolumeQuery object.
For example, the following query returns all the books in
your library that contain the word "bear":
newVolumeQuery(
'http://www.google.com/books/feeds/users' .
'/USER_ID/collections/library/volumes');
$query->setQuery('bear');
$feed = $books->getVolumeFeed($query);
]]>
For a list of the supported query parameters, see the
query parameters
section. In addition, you can search for books that have been
labeled by the user:
newVolumeQuery(
'http://www.google.com/books/feeds/users/' .
'USER_ID/collections/library/volumes');
$query->setCategory(
$query->setCategory('favorites');
$feed = $books->getVolumeFeed($query);
]]>
Updating books in a user's library
You can use the Book Search Data API to add a book to, or remove
a book from, a user's library. Ratings, reviews, and labels are valid
across all the collections of a user, and are thus edited using the
annotation feed (see Using community features).
Adding a book to a library
After authenticating, you can add books to the current user's library.
You can either create an entry from scratch if you
know the volume ID, or insert an entry read from any feed.
The following example creates a new entry and adds it to the library:
setId(new Zend_Gdata_App_Extension_Id(VOLUME_ID));
$books->insertVolume(
$entry,
Zend_Gdata_Books::MY_LIBRARY_FEED_URI
);
]]>
The following example adds an existing
VolumeEntry object to the library:
insertVolume(
$entry,
Zend_Gdata_Books::MY_LIBRARY_FEED_URI
);
]]>
Removing a book from a library
To remove a book from a user's library, call
deleteVolume() on the
VolumeEntry object.
deleteVolume($entry);
]]>