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 the next section.
303 MKWS Target Selection
304 ---------------------
306 MKWS accesses targets using the Pazpar2 metasearching engine. Although
307 Pazpar2 can be used directly, using a statically configured set of
308 targets, this usage is unusual. More often, Pazpar2 is fronted by the
309 Service Proxy (SP), which manages authentication, sessions, target
312 This document assumes the SP is used, and explains how to go about
313 making a set of targets (a "library") available, how to connect your
314 MKWS application to that library, and how to choose which of the
315 available targets to use.
318 ### Maintaining the library
320 The service proxy accesses sets of targets that are known as
321 "libraries". In general, each customer will have their own library,
322 though some standard libraries may be shared between many customers --
323 for example, a library containing all open-access academic journals.
324 A library can also contain other configuration information, including
325 the set of categories by which targets are classified for the library.
327 Libraries are maintained using MKAdmin (MasterKey
328 Admin). Specifically, those used by MKWS are generally maintained on
329 the "MKX Admin" installation at
330 <http://mkx-admin.indexdata.com/console/>
332 In general, Index Data will create a library for each customer, then
333 give the customer a username/password pair that they can use to enter
334 MKAdmin and administrate that library.
336 Once logged in, customers can select which targets to include (from
337 the list of several thousand that MKAdmin knows about), and make
338 customer-specific modifications -- e.g. overriding the titles of the
341 Most importantly, customers' administrators can add authentication
342 credentials that the Service Proxy will used on their behalf when
343 accessing subscription resources -- username/password pairs or proxies
344 to use for IP-based authentication. Note that **it is then crucial to
345 secure the library from use by unauthorised clients**, otherwise the
346 customer's paid subscriptions will be exploited.
348 Access to libraries is managed by creating one or more "User Access"
349 records in MKAdmin, under the tab of that name. Each of these records
350 provides a combination of credentials and other data that allow an
351 incoming MKWS client to be identified as having legitimate access to
352 the library. The authentication process, described below, works by
353 searching for a matching User Access record.
356 ### Authenticating your MWKS application onto the library
358 Some MKWS applications will be content to use the default library with
359 its selection of targets. Most, though, will want to define their own
360 library providing a different range of available targets. An important
361 case is that of applications that authenticate onto subscription
362 resources by means of backe-end site credentials stored in MKAdmin:
363 precautions must be taken so that such library accounts do not allow
366 Setting up such a library is a process of several stages.
368 #### Create the User Access account
370 Log in to MKAdmin administrate your library:
372 * Go to <http://mkx-admin.indexdata.com/console/>
373 * Enter the adminstrative username/password
374 * Go to the User Access tab
375 * Create an end-user account
376 * Depending on what authentication method it be used, set the
377 User Access account's username and password, or IP-address range, or
378 referring URL, or hostname.
380 If your MWKS application runs at a well-known, permanent address --
381 <http://yourname.com/app.html>, say -- you can set the User Access
382 record so that this originating URL is recognised by setting it into
383 the "Referring URL" field.
385 If your application accesses the Service Proxy by a unique virtual
386 hostname -- yourname.sp-mkws.indexdata.com, say -- you can tie the use
387 of this hostname to your library by setting the User Access record's
388 "Host Name" field to name of the host where the SP is accessed. **Note
389 that this is not secure, as other applications can use this virtual
390 hostname to gain access to your library.**
392 > TODO Authentication by IP address does not yet work correctly -- see
393 > bug MKWS-234 ("Improve SP configuration/proxying for better
396 Alternatively, your application can authenticate by username and
397 password credentials. This is a useful approach in several situations,
398 including when you need to specify the use of a different library from
399 usual one. To arrange for this, set the username and password as a
400 single string separated by a slash -- e.g. "mike/swordfish" -- into
401 the User Access record's Authentication field.
403 You can create multiple User Access records: for example, one that
404 uses Referring URL, and another that uses a username/password pair to
405 be used when running an application from a different URL.
407 #### Tell the application to use the library
409 In the HTML of the application, tell MKWS to authenticate on to the
410 Service Proxy. When IP-based, referer-based or hostname-based
411 authentication is used, this is very simple:
413 <script type="text/javascript">
414 var mkws_config = { service_proxy_auth:
415 "//sp-mkws.indexdata.com/service-proxy/?command=auth&action=perconfig" };
418 > TODO This should be the default setting
420 And ensure that access to the MWKS application is from the correct
421 Referrer URL or IP-range.
423 #### (Optional): access by a different virtual hostname
425 When hostname-based authentication is in use, it's necessary to access
426 the Service Proxy as the correctly named virtual host. This can be
427 done by setting the `service_proxy_auth` configuration item to a
428 URL containing that hostname, such as
429 <//yourname.sp-mkws.indexdata.com/service-proxy/?command=auth&action=perconfig>
431 > TODO It should be possible to change just the hostname without
432 > needing to repeat the rest of the URL (protocol, path, query)
434 > TODO When changing the SP authentication URL, the Pazpar2 URL should
435 > in general change along with it.
437 #### (Optional): embed credentials for access to the library
439 When credential-based authentication is in use (username and
440 password), it's necessary to pass these credentials into the Service
441 Proxy when establishing the session. This can most simply be done just
442 by setting the `service_proxy_auth` configuration item to a URL such as
443 <//sp-mkws.indexdata.com/service-proxy/?command=auth&action=perconfig&username=mike&password=swordfish>
445 > TODO It should be possible to add the username and password to the
446 > configuration without needing to repeat the rest of the URL.
448 #### (Optional): conceal credentials from HTML source
450 Using a credential-based Service-Proxy authentication URL such as the
451 one above reveals the the credentials to public view -- to anyone who
452 does View Source on the MKWS application. This may be acceptable for
453 some libraries, but is intolerable for those which provide
454 authenticated access to subscription resources.
456 In these circumstances, a more elaborate approach is necessary. The
457 idea is to make a URL local to the customer that is used for
458 authentication onto the Service Proxy, hiding the credentials in a
459 local rewrite rule. Then local mechanisms can be used to limit access
460 to that local authentication URL. Here is one way to do it when
461 Apache2 is the application's web-server, which we will call
464 - Add a rewriting authentication alias to the configuration:
467 RewriteRule /spauth/ http://mkws.indexdata.com/service-proxy/?command=auth&action=check,login&username=U&password=PW [P]
469 - Set the MKWS configuration item `service_proxy_auth` to
470 <http://yourname.com/spauth/>
471 - Protect access to the local path <http://yourname.com/spauth/>
472 (e.g. using a .htaccess file).
475 ### Choosing targets from the library
477 MKWS applications can choose what subset of the library's targets to
478 use, by means of several alternative settings on individual widgets or
479 in the `mkws_config` structure:
481 * `targets` -- contains a Pazpar2 targets string, typically of the form
482 "pz:id=" or "pz:id~" followed by a pipe-separated list of low-level
484 At present, these IDs can take one of two forms, depending on the
485 configuration of the Service Proxy being used: they may be based on
486 ZURLs (so a typical value would be something like
487 `pz:id=josiah.brown.edu:210/innopac|lui.indexdata.com:8080/solr4/select?fq=database:4902`)
488 or they may be UDBs (so a typical value would be something like
489 `pz:id=brown|artstor`)
491 * `targetfilter` -- contains a CQL query which is used to find relevant
492 targets from the relvant library. For example,
497 * `target` -- contains a single UDB, that of the sole target to be
500 This is merely syntactic sugar for "targetfilter" with the query
503 For example, a `Records` widget can be limited to searching only in
504 targets that have been categorised as news sources by providing an
505 attribute as follows:
507 <div class="mkwsRecords" targetfilter='categories=news'/>
513 ### Configuration object
515 The configuration object `mkws_config` may be created before including
516 the MKWS JavaScript code to modify default behaviour. This structure
517 is a key-value lookup table, whose entries are described in the table
518 below. All entries are optional, but if specified must be given values
519 of the specified type. If ommitted, each setting takes the indicated
520 default value; long default values are in footnotes to keep the table
524 Element Type Default Description
525 -------- ----- --------- ------------
526 debug_level int 1 Level of debugging output to emit. 0 = none, 1 = messages, 2 = messages with
527 datestamps, 3 = messages with datestamps and stack-traces.
529 facets array *Note 1* Ordered list of names of facets to display. Supported facet names are
530 `xtargets`, `subject` and `author`.
532 lang string en Code of the default language to display the UI in. Supported language codes are `en` =
533 English, `de` = German, `da` = Danish, and whatever additional languages are configured
534 using `language_*` entries (see below).
536 lang_options array [] A list of the languages to offer as options. If empty (the default), then all
537 configured languages are listed.
539 language_* hash Support for any number of languages can be added by providing entries whose name is
540 `language_` followed by the code of the language. See the separate section below for
543 pazpar2_url string *Note 2* The URL used to access the metasearch middleware. This service must be configured to
544 provide search results, facets, etc. It may be either unmediated or Pazpar2 the
545 MasterKey Service Proxy, which mediates access to an underlying Pazpar2 instance. In
546 the latter case, `service_proxy_auth` must be provided.
548 perpage_default string 20 The initial value for the number of records to show on each page.
550 perpage_options array *Note 3* A list of candidate page sizes. Users can choose between these to determine how many
551 records are displayed on each page of results.
553 query_width int 50 The width of the query box, in characters.
555 responsive_design_width int If defined, then the facets display moves between two locations as the screen-width
556 varies, as described above. The specified number is the threshhold width, in pixels,
557 at which the facets move between their two locations.
559 service_proxy_auth url *Note 4* A URL which, when `use_service_proxy` is true, is fetched once at the beginning of each
560 session to authenticate the user and establish a session that encompasses a defined set
561 of targets to search in.
563 service_proxy_auth_domain domain Can be set to the domain for which `service_proxy_auth` proxies authentication, so
564 that cookies are rewritten to appear to be from this domain. In general, this is not
565 necessary, as this setting defaults to the domain of `pazpar2_url`.
567 show_lang bool true Indicates whether or not to display the language menu.
569 show_perpage bool true Indicates whether or not to display the perpage menu.
571 show_sort bool true Indicates whether or not to display the sort menu.
573 show_switch bool true Indicates whether or not to display the switch menu, for switching between showing
574 retrieved records and target information.
576 sort_default string relevance The label of the default sort criterion to use. Must be one of those in the `sort`
579 sort_options array *Note 6* List of supported sort criteria. Each element of the list is itself a two-element list:
580 the first element of each sublist is a pazpar2 sort-expression such as `data:0` and
581 the second is a human-readable label such as `newest`.
583 use_service_proxy bool true If true, then a Service Proxy is used to deliver searching services rather than raw
587 Perhaps we should get rid of the `show_lang`, `show_perpage`,
588 `show_sort` and `show_switch` configuration items, and simply display the relevant menus
589 only when their containers are provided -- e.g. an `mkwsLang` element
590 for the language menu. But for now we retain these, as an easier route
591 to lightly customise the display than my changing providing a full HTML
596 1. ["sources", "subjects", "authors"]
598 2. /pazpar2/search.pz2
602 4. http://mkws.indexdata.com/service-proxy-auth
604 5. http://mkws.indexdata.com/service-proxy/
606 6. [["relevance"], ["title:1", "title"], ["date:0", "newest"], ["date:1", "oldest"]]
609 ### Language specification
611 Support for another UI language can be added by providing an entry in
612 the `mkws_config` object whose name is `language_` followed by the
613 name of the language: for example, `language_French` to support
614 French. Then value of this entry must be a key-value lookup table,
615 mapping the English-language strings of the UI into their equivalents
616 in the specified language. For example:
620 "Authors": "Auteurs",
621 "Subjects": "Sujets",
622 // ... and others ...
626 The following strings occurring in the UI can be translated:
642 In addition, facet names can be translated:
648 Finally, the names of fields in the full-record display can be
649 translated. These include, but may not be limited to:
659 ### jQuery UI popup invocation
661 The MasterKey Widget Set can be invoked in a popup window on top of the page.
663 Note that when using the `popup` layout, facilities from the jQuery UI
664 toolkit are used, so it's necessary to include both CSS and JavaScript
665 from that toolkit. The relevant lines are:
667 <script src="http://code.jquery.com/ui/1.10.3/jquery-ui.min.js"></script>
668 <link rel="stylesheet" type="text/css"
669 href="http://code.jquery.com/ui/1.10.3/themes/smoothness/jquery-ui.css" />
671 <div class="mkwsSearch"></div>
672 <div class="mkwsPopup" popup_width="1024" popup_height="650" popup_modal="0" popup_autoOpen="0" popup_button="input.mkwsButton">
673 <div class="mkwsSwitch"></div>
674 <div class="mkwsLang"></div>
675 <div class="mkwsResults"></div>
676 <div class="mkwsTargets"></div>
677 <div class="mkwsStat"></div>
681 Element Type Default Description
682 -------- ----- --------- ------------
683 popup_width string 880 Width of the popup window (if used), in
686 popup_height string 760 Height of the popup window (if used), in
689 popup_button string input.mkwsButton (Never change this.)
691 popup_modal string 0 Modal confirmation mode. Valid values are 0 or 1
693 popup_autoOpen string 1 Open popup window on load. Valid values are 0 or 1
698 ### The structure of the HTML generated by the MKWS widgets
700 In order to override the default CSS styles provided by the MasterKey Widget
701 Set, it's necessary to understand that structure of the HTML elements that are
702 generated within the components. This knowledge make it possible, for example,
703 to style each `<div>` with class `term` but only when it occurs inside an
704 element with ID `#mkwsTermlists`, so as to avoid inadvertently styling other
705 elements using the same class in the non-MKWS parts of the page.
707 The HTML structure is as follows. As in CSS, #ID indicates a unique identifier
708 and .CLASS indicates an instance of a class.
718 input#mkwsQuery type=text
719 input#mkwsButton type=submit
722 (no contents -- used only for masking)
743 span (for sequence number)
745 span (for other information such as author)
746 div.details (sometimes)
769 Copyright (C) 2013-2014 by IndexData ApS, <http://www.indexdata.com>