1 % Embedded metasearching with the MasterKey Widget Set
8 There are lots of practical problems in building resource discovery
9 solutions. One of the biggest, and most ubiquitous is incorporating
10 metasearching functionality into existing web-sites -- for example,
11 content-management systems, library catalogues or intranets. In
12 general, even when access to core metasearching functionality is
13 provided by simple web-services such as
14 [Pazpar2](http://www.indexdata.com/pazpar2), integration work is seen
15 as a major part of most projects.
17 Index Data provides several different toolkits for communicating with
18 its metasearching middleware, trading off varying degrees of
19 flexibility against convenience:
21 * pz2.js -- a low-level JavaScript library for interrogating the
22 Service Proxy and Pazpar2. It allows the HTML/JavaScript programmer
23 to create JavaScript applications display facets, records, etc. that
24 are fetched from the metasearching middleware.
26 * masterkey-ui-core -- a higher-level, complex JavaScript library that
27 uses pz2.js to provide the pieces needed for building a
28 full-featured JavaScript application.
30 * MasterKey Demo UI -- an example of a searching application built on
31 top of masterkey-ui-core. Available as a public demo at
32 http://mk2.indexdata.com/
34 * MKDru -- a toolkit for embedding MasterKey-like searching into
37 All of these approaches require programming to a greater or lesser
38 extent. Against this backdrop, we introduced MKWS (the MasterKey
39 Widget Set) -- a set of simple, very high-level HTML+CSS+JavaScript
40 components that can be incorporated into any web-site to provide
41 MasterKey searching facilities. By placing `<div>`s with well-known
42 identifiers in any HTML page, the various components of an application
43 can be embedded: search-boxes, results areas, target information, etc.
49 The following is a complete MKWS-based searching application:
53 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
54 <title>MKWS demo client</title>
55 <script type="text/javascript" src="http://mkws.indexdata.com/mkws-complete.js"></script>
56 <link rel="stylesheet" href="http://mkws.indexdata.com/mkws.css" />
59 <div id="mkwsSearch"></div>
60 <div id="mkwsResults"></div>
64 Go ahead, try it! You don't even need a web-server. Just copy and
65 paste this HTML into a file on your computer -- `/tmp/magic.html`,
66 say -- and point your web-browser at it:
67 `file:///tmp/magic.html`. Just like that, you have working
74 If you know any HTML, the structure of the file will be familar to
75 you: the `<html>` element at the top level contains a `<head>` and a
76 `<body>`. In addition to whatever else you might want to put on your
77 page, you can add MKWS elements.
79 These fall into two categories. First, the prerequisites in the HTML
80 header, which are loaded from the tool site mkws.indexdata.com:
83 contains all the JavaScript needed by the widget-set.
86 provides the default CSS styling
88 Second, within the HTML body, `<div>` elements with special IDs that
89 begin `mkws` can be provided. These are filled in by the MKWS code,
90 and provide the components of the searching UI. The very simple
91 application above has only two such components: a search box and a
92 results area. But more are supported. The main `<div>`s are:
94 * `mkwsSearch` -- provides the search box and button.
96 * `mkwsResults` -- provides the results area, including a list of
97 brief records (which open out into full versions when clicked),
98 paging for large results sets, facets for refining a search,
99 sorting facilities, etc.
101 * `mkwsLang` -- provides links to switch between one of several
102 different UI languages. By default, English, Danish and German are
105 * `mkwsSwitch` -- provides links to switch between a view of the
106 result records and of the targets that provide them. Only
107 meaningful when `mkwsTargets` is also provided.
109 * `mkwsTargets` -- the area where per-target information will appear
110 when selected by the link in the `mkwsSwitch` area. Of interest
111 mostly for fault diagnosis rather than for end-users.
113 * `mkwsStat` --provides a status line summarising the statistics of
116 To see all of these working together, just put them all into the HTML
119 <div id="mkwsSwitch"></div>
120 <div id="mkwsLang"></div>
121 <div id="mkwsSearch"></div>
122 <div id="mkwsResults"></div>
123 <div id="mkwsTargets"></div>
124 <div id="mkwsStat"></div>
129 Many aspects of the behaviour of MKWS can be modified by setting
130 parameters into the `mkws_config` object. **This must be done *before*
131 including the MKWS JavaScript** so that when that code is executed it
132 can refer to the configuration values. So the HTML header looks like
135 <script type="text/javascript">
138 sort_default: "title",
142 <script type="text/javascript" src="http://mkws.indexdata.com/mkws-complete.js"></script>
144 This configuration sets the UI language to Danish (rather than the
145 default of English), initially sorts search results by title rather
146 than relevance (though as always this can be changed in the UI) and
147 makes the search box a bit wider than the default.
149 The full set of supported configuration items is described in the
150 reference guide below.
153 Control over HTML and CSS
154 -------------------------
156 More sophisticated applications will not simply place the `<div>`s
157 together, but position them carefully within an existing page
158 framework -- such as a Drupal template, an OPAC or a SharePoint page.
160 While it's convenient for simple applications to use a monolithic
161 `mkwsResults` area which contains record, facets, sorting options,
162 etc., customised layouts may wish to treat each of these components
163 separately. In this case, `mkwsResults` can be omitted, and the
164 following lower-level components provided instead:
166 * `mkwsTermlists` -- provides the facets
168 * `mkwsRanking` -- provides the options for how records are sorted and
169 how many are included on each page of results.
171 * `mkwsPager` -- provides the links for navigating back and forth
172 through the pages of records.
174 * `mkwsNavi` -- when a search result has been narrowed by one or more
175 facets, this area shows the names of those facets, and allows the
176 selected values to be clicked in order to remove them.
178 * `mkwsRecords` -- lists the actual result records.
180 Customisation of MKWS searching widgets can also be achieved by
181 overriding the styles set in the toolkit's CSS stylesheet. The default
182 styles can be inspected in `mkws.css` and overridden in any
183 styles that appears later in the HTML than that file. At the simplest
184 level, this might just mean changing fonts, sizes and colours, but
185 more fundamental changes are also possible.
187 To properly apply styles, it's necessary to understand how the HTML is
188 structured, e.g. which elements are nested within which
189 containers. The structures used by the widget-set are described in the
190 reference guide below.
197 ### Message of the day
199 Some applications might like to open with content in the area that
200 will subsequently be filled with result-records -- a message of the
201 day, a welcome message or a help page. This can be done by placing an
202 `mkwsMOTD` division anywhere on the page. It will be moved into the
203 `mkwsResults` area and initially displayed, but will be hidden when a
207 ### Customised display using Handlebars templates
209 Certain aspects of the widget-set's display can be customised by
210 providing Handlebars templates with well-known classes that begin with
211 the string `mkwsTemplate_`. At present, the supported templates are:
213 * `mkwsTemplate_Summary` -- used for each summary record in a list of
216 * `mkwsTemplate_Record` -- used when displaying a full record.
218 For both of these the metadata record is passed in, and its fields can
219 be referenced in the template. As well as the metadata fields
220 (`md-*`), two special fields are provided to the `mkwsTemplate_Summary`
221 template, for creating popup links for full records. These are `_id`,
222 which must be provided as the `id` attribute of a link tag, and
223 `_onclick`, which must be provided as the `onclick` attribute.
225 For example, an application can install a simple author+title summary
226 record in place of the usual one providing the following template:
228 <script class="mkwsTemplate_Summary" type="text/x-handlebars-template">
230 <span>{{md-author}}</span>
232 <a href="#" id="{{_id}}" onclick="{{_onclick}}">
237 For details of Handlebars template syntax, see
238 [the online documentation](http://handlebarsjs.com/).
241 ### Responsive design
243 Metasearching applications may need to appear differently on
244 small-screened mobile devices, or change their appearance when
245 screen-width changes (as when a small device is rotated). To achieve
246 this, MKWS supports responsive design which will move the termlists to
247 the bottom on narrow screens and to the sidebar on wide screens.
249 To turn on this behaviour, set the `responsive_design_width` to the desired
250 threshhold width in pixels. For example:
252 <script type="text/javascript">
254 responsive_design_width: 990
258 If individual result-related components are in use in place of the
259 all-in-one mkwsResults, then the redesigned application needs to
260 specify the locations where the termlists should appear in both
261 cases. In this case, wrap the wide-screen `mkwsTermlists` element in a
262 `mkwsTermlists-Container-wide` element; and provide an
263 `mkwsTermlists-Container-narrow` element in the place where the narrow-screen
264 termlists should appear.
267 ### Popup results with jQuery UI
269 The [jQuery UI library](http://en.wikipedia.org/wiki/JQuery_UI)
270 can be used to construct MKWS applications in which the only component
271 generally visible on the page is a search box, and the results appear
272 in a popup. The key part of such an application is this invocation of
273 the MKWS jQuery plugin:
275 <div class="mkwsSearch"></div>
276 <div class="mkwsPopup" popup_width="1024" popup_height="650" popup_modal="0" popup_autoOpen="0" popup_button="input.mkwsButton">
277 <div class="mkwsSwitch"></div>
278 <div class="mkwsLang"></div>
279 <div class="mkwsResults"></div>
280 <div class="mkwsTargets"></div>
281 <div class="mkwsStat"></div>
284 The necessary scaffolding can be seen in an example application,
285 http://example.indexdata.com/index-popup.html
288 ### Authentication and target configuration
290 By default, MKWS configures itself to use a demonstration account on a
291 service hosted by mkws.indexdata.com. This account (username `demo`,
292 password `demo`) provides access to about a dozen free data
293 sources. Authentication onto this service is via an authentication URL
294 on the same MKWS server, so no explicit configuration is needed.
296 In order to search in a customised set of targets, including
297 subscription resources, it's necessary to create an account with
298 Index Data's hosted service proxy, and protect that account with
299 authentication tokens (to prevent unauthorised use of subscription
300 resources). For information on how to do this, see
301 [MKWS Target Selection](library-configuration.html)
304 MKWS Target Selection
305 ---------------------
307 MKWS accesses targets using the Pazpar2 metasearching engine. Although
308 Pazpar2 can be used directly, using a statically configured set of
309 targets, this usage is unusual. More often, Pazpar2 is fronted by the
310 Service Proxy (SP), which manages authentication, sessions, target
313 This document assumes the SP is used, and explains how to go about
314 making a set of targets (a "library") available, how to connect your
315 MKWS application to that library, and how to choose which of the
316 available targets to use.
319 ### Maintaining the library
321 The service proxy accesses sets of targets that are known as
322 "libraries". In general, each customer will have their own library,
323 though some standard libraries may be shared between many customers --
324 for example, a library containing all open-access academic journals.
325 A library can also contain other configuration information, including
326 the set of categories by which targets are classified for the library.
328 Libraries are maintained using MKAdmin (MasterKey
329 Admin). Specifically, those used by MKWS are generally maintained on
330 the "MKX Admin" installation at
331 <http://mkx-admin.indexdata.com/console/>
333 In general, Index Data will create a library for each customer, then
334 give the customer a username/password pair that they can use to enter
335 MKAdmin and administrate that library.
337 Once logged in, customers can select which targets to include (from
338 the list of several thousand that MKAdmin knows about), and make
339 customer-specific modifications -- e.g. overriding the titles of the
342 Most importantly, customers' administrators can add authentication
343 credentials that the Service Proxy will used on their behalf when
344 accessing subscription resources -- username/password pairs or proxies
345 to use for IP-based authentication. Note that **it is then crucial to
346 secure the library from use by unauthorised clients**, otherwise the
347 customer's paid subscriptions will be exploited.
349 Access to libraries is managed by creating one or more "User Access"
350 records in MKAdmin, under the tab of that name. Each of these records
351 provides a combination of credentials and other data that allow an
352 incoming MKWS client to be identified as having legitimate access to
353 the library. The authentication process, described below, works by
354 searching for a matching User Access record.
357 ### Authenticating your MWKS application onto the library
359 Some MKWS applications will be content to use the default library with
360 its selection of targets. Most, though, will want to define their own
361 library providing a different range of available targets. An important
362 case is that of applications that authenticate onto subscription
363 resources by means of backe-end site credentials stored in MKAdmin:
364 precautions must be taken so that such library accounts do not allow
367 Setting up such a library is a process of several stages.
369 #### Create the User Access account
371 Log in to MKAdmin administrate your library:
373 * Go to <http://mkx-admin.indexdata.com/console/>
374 * Enter the adminstrative username/password
375 * Go to the User Access tab
376 * Create an end-user account
377 * Depending on what authentication method it be used, set the
378 User Access account's username and password, or IP-address range, or
379 referring URL, or hostname.
381 If your MWKS application runs at a well-known, permanent address --
382 <http://yourname.com/app.html>, say -- you can set the User Access
383 record so that this originating URL is recognised by setting it into
384 the "Referring URL" field.
386 If your application accesses the Service Proxy by a unique virtual
387 hostname -- yourname.sp-mkws.indexdata.com, say -- you can tie the use
388 of this hostname to your library by setting the User Access record's
389 "Host Name" field to name of the host where the SP is accessed. **Note
390 that this is not secure, as other applications can use this virtual
391 hostname to gain access to your library.**
393 > TODO Authentication by IP address does not yet work correctly -- see
394 > bug MKWS-234 ("Improve SP configuration/proxying for better
397 Alternatively, your application can authenticate by username and
398 password credentials. This is a useful approach in several situations,
399 including when you need to specify the use of a different library from
400 usual one. To arrange for this, set the username and password as a
401 single string separated by a slash -- e.g. "mike/swordfish" -- into
402 the User Access record's Authentication field.
404 You can create multiple User Access records: for example, one that
405 uses Referring URL, and another that uses a username/password pair to
406 be used when running an application from a different URL.
408 #### Tell the application to use the library
410 In the HTML of the application, tell MKWS to authenticate on to the
411 Service Proxy. When IP-based, referer-based or hostname-based
412 authentication is used, this is very simple:
414 <script type="text/javascript">
415 var mkws_config = { service_proxy_auth:
416 "//sp-mkws.indexdata.com/service-proxy/?command=auth&action=perconfig" };
419 > TODO This should be the default setting
421 And ensure that access to the MWKS application is from the correct
422 Referrer URL or IP-range.
424 #### (Optional): access by a different virtual hostname
426 When hostname-based authentication is in use, it's necessary to access
427 the Service Proxy as the correctly named virtual host. This can be
428 done by setting the `service_proxy_auth` configuration item to a
429 URL containing that hostname, such as
430 <//yourname.sp-mkws.indexdata.com/service-proxy/?command=auth&action=perconfig>
432 > TODO It should be possible to change just the hostname without
433 > needing to repeat the rest of the URL (protocol, path, query)
435 > TODO When changing the SP authentication URL, the Pazpar2 URL should
436 > in general change along with it.
438 #### (Optional): embed credentials for access to the library
440 When credential-based authentication is in use (username and
441 password), it's necessary to pass these credentials into the Service
442 Proxy when establishing the session. This can most simply be done just
443 by setting the `service_proxy_auth` configuration item to a URL such as
444 <//sp-mkws.indexdata.com/service-proxy/?command=auth&action=perconfig&username=mike&password=swordfish>
446 > TODO It should be possible to add the username and password to the
447 > configuration without needing to repeat the rest of the URL.
449 #### (Optional): conceal credentials from HTML source
451 Using a credential-based Service-Proxy authentication URL such as the
452 one above reveals the the credentials to public view -- to anyone who
453 does View Source on the MKWS application. This may be acceptable for
454 some libraries, but is intolerable for those which provide
455 authenticated access to subscription resources.
457 In these circumstances, a more elaborate approach is necessary. The
458 idea is to make a URL local to the customer that is used for
459 authentication onto the Service Proxy, hiding the credentials in a
460 local rewrite rule. Then local mechanisms can be used to limit access
461 to that local authentication URL. Here is one way to do it when
462 Apache2 is the application's web-server, which we will call
465 - Add a rewriting authentication alias to the configuration:
468 RewriteRule /spauth/ http://mkws.indexdata.com/service-proxy/?command=auth&action=check,login&username=U&password=PW [P]
470 - Set the MKWS configuration item `service_proxy_auth` to
471 <http://yourname.com/spauth/>
472 - Protect access to the local path <http://yourname.com/spauth/>
473 (e.g. using a .htaccess file).
476 ### Choosing targets from the library
478 MKWS applications can choose what subset of the library's targets to
479 use, by means of several alternative settings on individual widgets or
480 in the `mkws_config` structure:
482 * `targets` -- contains a Pazpar2 targets string, typically of the form
483 "pz:id=" or "pz:id~" followed by a pipe-separated list of low-level
485 At present, these IDs can take one of two forms, depending on the
486 configuration of the Service Proxy being used: they may be based on
487 ZURLs (so a typical value would be something like
488 `pz:id=josiah.brown.edu:210/innopac|lui.indexdata.com:8080/solr4/select?fq=database:4902`)
489 or they may be UDBs (so a typical value would be something like
490 `pz:id=brown|artstor`)
492 * `targetfilter` -- contains a CQL query which is used to find relevant
493 targets from the relvant library. For example,
498 * `target` -- contains a single UDB, that of the sole target to be
501 This is merely syntactic sugar for "targetfilter" with the query
504 For example, a `Records` widget can be limited to searching only in
505 targets that have been categorised as news sources by providing an
506 attribute as follows:
508 <div class="mkwsRecords" targetfilter='categories=news'/>
514 ### Configuration object
516 The configuration object `mkws_config` may be created before including
517 the MKWS JavaScript code to modify default behaviour. This structure
518 is a key-value lookup table, whose entries are described in the table
519 below. All entries are optional, but if specified must be given values
520 of the specified type. If ommitted, each setting takes the indicated
521 default value; long default values are in footnotes to keep the table
525 Element Type Default Description
526 -------- ----- --------- ------------
527 debug_level int 1 Level of debugging output to emit. 0 = none, 1 = messages, 2 = messages with
528 datestamps, 3 = messages with datestamps and stack-traces.
530 facets array *Note 1* Ordered list of names of facets to display. Supported facet names are
531 `xtargets`, `subject` and `author`.
533 lang string en Code of the default language to display the UI in. Supported language codes are `en` =
534 English, `de` = German, `da` = Danish, and whatever additional languages are configured
535 using `language_*` entries (see below).
537 lang_options array [] A list of the languages to offer as options. If empty (the default), then all
538 configured languages are listed.
540 language_* hash Support for any number of languages can be added by providing entries whose name is
541 `language_` followed by the code of the language. See the separate section below for
544 pazpar2_url string *Note 2* The URL used to access the metasearch middleware. This service must be configured to
545 provide search results, facets, etc. It may be either unmediated or Pazpar2 the
546 MasterKey Service Proxy, which mediates access to an underlying Pazpar2 instance. In
547 the latter case, `service_proxy_auth` must be provided.
549 perpage_default string 20 The initial value for the number of records to show on each page.
551 perpage_options array *Note 3* A list of candidate page sizes. Users can choose between these to determine how many
552 records are displayed on each page of results.
554 query_width int 50 The width of the query box, in characters.
556 responsive_design_width int If defined, then the facets display moves between two locations as the screen-width
557 varies, as described above. The specified number is the threshhold width, in pixels,
558 at which the facets move between their two locations.
560 service_proxy_auth url *Note 4* A URL which, when `use_service_proxy` is true, is fetched once at the beginning of each
561 session to authenticate the user and establish a session that encompasses a defined set
562 of targets to search in.
564 service_proxy_auth_domain domain Can be set to the domain for which `service_proxy_auth` proxies authentication, so
565 that cookies are rewritten to appear to be from this domain. In general, this is not
566 necessary, as this setting defaults to the domain of `pazpar2_url`.
568 show_lang bool true Indicates whether or not to display the language menu.
570 show_perpage bool true Indicates whether or not to display the perpage menu.
572 show_sort bool true Indicates whether or not to display the sort menu.
574 show_switch bool true Indicates whether or not to display the switch menu, for switching between showing
575 retrieved records and target information.
577 sort_default string relevance The label of the default sort criterion to use. Must be one of those in the `sort`
580 sort_options array *Note 6* List of supported sort criteria. Each element of the list is itself a two-element list:
581 the first element of each sublist is a pazpar2 sort-expression such as `data:0` and
582 the second is a human-readable label such as `newest`.
584 use_service_proxy bool true If true, then a Service Proxy is used to deliver searching services rather than raw
588 Perhaps we should get rid of the `show_lang`, `show_perpage`,
589 `show_sort` and `show_switch` configuration items, and simply display the relevant menus
590 only when their containers are provided -- e.g. an `mkwsLang` element
591 for the language menu. But for now we retain these, as an easier route
592 to lightly customise the display than my changing providing a full HTML
597 1. ["sources", "subjects", "authors"]
599 2. /pazpar2/search.pz2
603 4. http://mkws.indexdata.com/service-proxy-auth
605 5. http://mkws.indexdata.com/service-proxy/
607 6. [["relevance"], ["title:1", "title"], ["date:0", "newest"], ["date:1", "oldest"]]
610 ### Language specification
612 Support for another UI language can be added by providing an entry in
613 the `mkws_config` object whose name is `language_` followed by the
614 name of the language: for example, `language_French` to support
615 French. Then value of this entry must be a key-value lookup table,
616 mapping the English-language strings of the UI into their equivalents
617 in the specified language. For example:
621 "Authors": "Auteurs",
622 "Subjects": "Sujets",
623 // ... and others ...
627 The following strings occurring in the UI can be translated:
643 In addition, facet names can be translated:
649 Finally, the names of fields in the full-record display can be
650 translated. These include, but may not be limited to:
660 ### jQuery UI popup invocation
662 The MasterKey Widget Set can be invoked in a popup window on top of the page.
664 Note that when using the `popup` layout, facilities from the jQuery UI
665 toolkit are used, so it's necessary to include both CSS and JavaScript
666 from that toolkit. The relevant lines are:
668 <script src="http://code.jquery.com/ui/1.10.3/jquery-ui.min.js"></script>
669 <link rel="stylesheet" type="text/css"
670 href="http://code.jquery.com/ui/1.10.3/themes/smoothness/jquery-ui.css" />
672 <div class="mkwsSearch"></div>
673 <div class="mkwsPopup" popup_width="1024" popup_height="650" popup_modal="0" popup_autoOpen="0" popup_button="input.mkwsButton">
674 <div class="mkwsSwitch"></div>
675 <div class="mkwsLang"></div>
676 <div class="mkwsResults"></div>
677 <div class="mkwsTargets"></div>
678 <div class="mkwsStat"></div>
682 Element Type Default Description
683 -------- ----- --------- ------------
684 popup_width string 880 Width of the popup window (if used), in
687 popup_height string 760 Height of the popup window (if used), in
690 popup_button string input.mkwsButton (Never change this.)
692 popup_modal string 0 Modal confirmation mode. Valid values are 0 or 1
694 popup_autoOpen string 1 Open popup window on load. Valid values are 0 or 1
699 ### The structure of the HTML generated by the MKWS widgets
701 In order to override the default CSS styles provided by the MasterKey Widget
702 Set, it's necessary to understand that structure of the HTML elements that are
703 generated within the components. This knowledge make it possible, for example,
704 to style each `<div>` with class `term` but only when it occurs inside an
705 element with ID `#mkwsTermlists`, so as to avoid inadvertently styling other
706 elements using the same class in the non-MKWS parts of the page.
708 The HTML structure is as follows. As in CSS, #ID indicates a unique identifier
709 and .CLASS indicates an instance of a class.
719 input#mkwsQuery type=text
720 input#mkwsButton type=submit
723 (no contents -- used only for masking)
744 span (for sequence number)
746 span (for other information such as author)
747 div.details (sometimes)
770 Copyright (C) 2013-2014 by IndexData ApS, <http://www.indexdata.com>