MKWS demo client

`s with well-known identifiers in any HTML page, the various components of an application can be embedded: search-boxes, results areas, target information, etc. Simple Example -------------- The following is a complete MKWS-based searching application: MKWS demo client

Go ahead, try it! You don't even need a web-server. Just copy and paste this HTML into a file on your computer -- `/tmp/magic.html`, say -- and point your web-browser at it: `file:///tmp/magic.html`. Just like that, you have working metasearching. How the example works --------------------- If you know any HTML, the structure of the file will be familar to you: the `` element at the top level contains a `` and a ``. In addition to whatever else you might want to put on your page, you can add MKWS elements. These fall into two categories. First, the prerequisites in the HTML header, which are loaded from the tool site mkws.indexdata.com: * `mkws-complete.js` contains all the JavaScript needed by the widget-set. * `mkws.css` provides the default CSS styling Second, within the HTML body, `

` elements with special IDs that begin `mkws` can be provided. These are filled in by the MKWS code, and provide the components of the searching UI. The very simple application above has only two such components: a search box and a results area. But more are supported. The main `

`s are: * `mkwsSearch` -- provides the search box and button. * `mkwsResults` -- provides the results area, including a list of brief records (which open out into full versions when clicked), paging for large results sets, facets for refining a search, sorting facilities, etc. * `mkwsLang` -- provides links to switch between one of several different UI languages. By default, English, Danish and German are provided. * `mkwsSwitch` -- provides links to switch between a view of the result records and of the targets that provide them. Only meaningful when `mkwsTargets` is also provided. * `mkwsTargets` -- the area where per-target information will appear when selected by the link in the `mkwsSwitch` area. Of interest mostly for fault diagnosis rather than for end-users. * `mkwsStat` --provides a status line summarising the statistics of the various targets. To see all of these working together, just put them all into the HTML `` like so:

Configuration ------------- Many aspects of the behaviour of MKWS can be modified by setting parameters into the `mkws_config` object. **This must be done *before* including the MKWS JavaScript** so that when that code is executed it can refer to the configuration values. So the HTML header looks like this: This configuration sets the UI language to Danish (rather than the default of English), initially sorts search results by title rather than relevance (though as always this can be changed in the UI) and makes the search box a bit wider than the default. The full set of supported configuration items is described in the reference guide below. Control over HTML and CSS ------------------------- More sophisticated applications will not simply place the `

`s together, but position them carefully within an existing page framework -- such as a Drupal template, an OPAC or a SharePoint page. While it's convenient for simple applications to use a monolithic `mkwsResults` area which contains record, facets, sorting options, etc., customised layouts may wish to treat each of these components separately. In this case, `mkwsResults` can be omitted, and the following lower-level components provided instead: * `mkwsTermlists` -- provides the facets * `mkwsRanking` -- provides the options for how records are sorted and how many are included on each page of results. * `mkwsPager` -- provides the links for navigating back and forth through the pages of records. * `mkwsNavi` -- when a search result has been narrowed by one or more facets, this area shows the names of those facets, and allows the selected values to be clicked in order to remove them. * `mkwsRecords` -- lists the actual result records. Customisation of MKWS searching widgets can also be achieved by overriding the styles set in the toolkit's CSS stylesheet. The default styles can be inspected in `mkws.css` and overridden in any styles that appears later in the HTML than that file. At the simplest level, this might just mean changing fonts, sizes and colours, but more fundamental changes are also possible. To properly apply styles, it's necessary to understand how the HTML is structured, e.g. which elements are nested within which containers. The structures used by the widget-set are described in the reference guide below. Refinements ----------- ### Message of the day Some applications might like to open with content in the area that will subsequently be filled with result-records -- a message of the day, a welcome message or a help page. This can be done by placing an `mkwsMOTD` division anywhere on the page. It will be moved into the `mkwsResults` area and initially displayed, but will be hidden when a search is made. ### Customised display using Handlebars templates Certain aspects of the widget-set's display can be customised by providing Handlebars templates with well-known classes that begin with the string `mkwsTemplate_`. At present, the supported templates are: * `mkwsTemplate_Summary` -- used for each summary record in a list of results. * `mkwsTemplate_Record` -- used when displaying a full record. For both of these the metadata record is passed in, and its fields can be referenced in the template. As well as the metadata fields (`md-*`), two special fields are provided to the `mkwsTemplate_Summary` template, for creating popup links for full records. These are `_id`, which must be provided as the `id` attribute of a link tag, and `_onclick`, which must be provided as the `onclick` attribute. For example, an application can install a simple author+title summary record in place of the usual one providing the following template: For details of Handlebars template syntax, see [the online documentation](http://handlebarsjs.com/). ### Responsive design Metasearching applications may need to appear differently on small-screened mobile devices, or change their appearance when screen-width changes (as when a small device is rotated). To achieve this, MKWS supports responsive design which will move the termlists to the bottom on narrow screens and to the sidebar on wide screens. To turn on this behaviour, set the `responsive_design_width` to the desired threshhold width in pixels. For example: If individual result-related components are in use in place of the all-in-one mkwsResults, then the redesigned application needs to specify the locations where the termlists should appear in both cases. In this case, wrap the wide-screen `mkwsTermlists` element in a `mkwsTermlistContainer1` element; and provide an `mkwsTermlistContainer2` element in the place where the narrow-screen termlists should appear. ### Popup results with jQuery UI The [jQuery UI library](http://en.wikipedia.org/wiki/JQuery_UI) can be used to construct MKWS applications in which the only component generally visible on the page is a search box, and the results appear in a popup. The key part of such an application is this invocation of the MKWS jQuery plugin: The necessary scaffolding can be seen in an example application, http://example.indexdata.com/index-popup.html ### Authentication and target configuration By default, MKWS configures itself to use a demonstration account on a service hosted by mkws.indexdata.com. This account (username `demo`, password `demo`) provides access to about a dozen free data sources. Authentication onto this service is via an authentication URL on the same MKWS server, so no explicit configuration is needed. In order to search in a customised set of targets, including subscription resources, it's necessary to create an account with Index Data's hosted service proxy, and protect that account with authentication tokens (to prevent unauthorised use of subscription resources). But in order to gain access to those resources, the authentication tokens have to be available to the widgets in some way, and simple embedding them in the JavaScript configuration is not acceptable because they are easy to read from there. The solution to this problem is in three steps. First the application's web-server creates a rewriting rule that takes an innocuous URL like http://example.indexdata.com/service-proxy-auth/ and rewrites it as an access to Index Data's authentication service with authentication credentials embedded. This can be done using Apache2 directives such as RewriteEngine on RewriteRule /service-proxy-auth/ http://mkws.indexdata.com/service-proxy/?command=auth&action=login&username=U&password=PW [P] Because the credentials appear only in the application's web-server configuration, they are not visible to malicious users. Second, the broader application that includes MKWS widgets must protect access to the authentication URL on its own web-server. This can be done using IP authentication, a local username/password scheme, Kerberos or any other means. Third, the MKWS application must be configured to use the application-hosted authentication URL instead of the default one. This is done by means of the `service_proxy_auth` configuration element, which should be set to the authentication URL. Once these three steps are taken, the MKWS application will authenticate by means of a special URL on the application's web server, which the application prevents unauthorised access to, and the underlying credentials are hidden. Reference Guide --------------- ### Configuration object The configuration object `mkws_config` may be created before including the MKWS JavaScript code to modify default behaviour. This structure is a key-value lookup table, whose entries are described in the table below. All entries are optional, but if specified must be given values of the specified type. If ommitted, each setting takes the indicated default value; long default values are in footnotes to keep the table reasonably narrow. --- Element Type Default Description -------- ----- --------- ------------ debug_level int 1 Level of debugging output to emit. 0 = none, 1 = messages, 2 = messages with datestamps, 3 = messages with datestamps and stack-traces. facets array *Note 1* Ordered list of names of facets to display. Supported facet names are `xtargets`, `subject` and `author`. lang string en Code of the default language to display the UI in. Supported language codes are `en` = English, `de` = German, `da` = Danish, and whatever additional languages are configured using `language_*` entries (see below). lang_options array [] A list of the languages to offer as options. If empty (the default), then all configured languages are listed. language_* hash Support for any number of languages can be added by providing entries whose name is `language_` followed by the code of the language. See the separate section below for details. pazpar2_url string *Note 2* The URL used to access the metasearch middleware. This service must be configured to provide search results, facets, etc. It may be either unmediated or Pazpar2 the MasterKey Service Proxy, which mediates access to an underlying Pazpar2 instance. In the latter case, `service_proxy_auth` must be provided. perpage_default string 20 The initial value for the number of records to show on each page. perpage_options array *Note 3* A list of candidate page sizes. Users can choose between these to determine how many records are displayed on each page of results. query_width int 50 The width of the query box, in characters. responsive_design_width int If defined, then the facets display moves between two locations as the screen-width varies, as described above. The specified number is the threshhold width, in pixels, at which the facets move between their two locations. service_proxy_auth url *Note 4* A URL which, when `use_service_proxy` is true, is fetched once at the beginning of each session to authenticate the user and establish a session that encompasses a defined set of targets to search in. service_proxy_auth_domain domain Can be set to the domain for which `service_proxy_auth` proxies authentication, so that cookies are rewritten to appear to be from this domain. In general, this is not necessary, as this setting defaults to the domain of `pazpar2_url`. show_lang bool true Indicates whether or not to display the language menu. show_perpage bool true Indicates whether or not to display the perpage menu. show_sort bool true Indicates whether or not to display the sort menu. sort_default string relevance The label of the default sort criterion to use. Must be one of those in the `sort` array. sort_options array *Note 6* List of supported sort criteria. Each element of the list is itself a two-element list: the first element of each sublist is a pazpar2 sort-expression such as `data:0` and the second is a human-readable label such as `newest`. use_service_proxy bool true If true, then a Service Proxy is used to deliver searching services rather than raw Pazpar2. --- Perhaps we should get rid of the `show_lang`, `show_perpage` and `show_sort` configuration items, and simply display the relevant menus only when their containers are provided -- e.g. an `mkwsLang` element for the language menu. But for now we retain these, as an easier route to lightly customise the display than my changing providing a full HTML structure. #### Notes 1. ["sources", "subjects", "authors"] 2. /pazpar2/search.pz2 3. [10, 20, 30, 50] 4. http://mkws.indexdata.com/service-proxy-auth 5. http://mkws.indexdata.com/service-proxy/ 6. [["relevance"], ["title:1", "title"], ["date:0", "newest"], ["date:1", "oldest"]] ### Language specification Support for another UI language can be added by providing an entry in the `mkws_config` object whose name is `language_` followed by the name of the language: for example, `language_French` to support French. Then value of this entry must be a key-value lookup table, mapping the English-language strings of the UI into their equivalents in the specified language. For example: var mkws_config = { language_French: { "Authors": "Auteurs", "Subjects": "Sujets", // ... and others ... } } The following strings occurring in the UI can be translated: `Displaying`, `Next`, `Prev`, `Records`, `Search`, `Sort by`, `Targets`, `Termlists`, `and show`, `found`, `of`, `per page` and `to`. In addition, facet names can be translated: `Authors`, `Sources` and `Subjects`. Finally, the names of fields in the full-record display can be translated. These include, but may not be limited to: `Author`, `Date`, `Location`, `Subject` and `Title`. ### jQuery plugin invocation The MasterKey Widget Set can be invoked as a jQuery plugin rather than by providing an HTML skeleton explicitly. When this approach is used, the invocation is a single line of JavaScript: This code should be inserted in the page at the position where the metasearch should occur. When invoking this plugin, a key-value lookup table of named options may be passed in to modify the default behaviour, as in the exaple above. The available options are as follows: --- Element Type Default Description -------- ----- --------- ------------ layout string popup Specifies how the user interface should appear. Options are `table` (the default, with facets at the bottom), `div` (with facets at the side) and `popup` (to obtain a popup window). width int 880 Width of the popup window (if used), in pixels. height int 760 Height of the popup window (if used), in pixels. id_button string input#mkwsButton (Never change this.) id_popup string #mkwsPopup (Never change this.) --- Note that when using the `popup` layout, facilities from the jQuery UI toolkit are used, so it's necessary to include both CSS and JavaScript from that toolkit. The relevant lines are: ### The structure of the HTML generated by the MKWS widgets In order to override the default CSS styles provided by the MasterKey Widget Set, it's necessary to understand that structure of the HTML elements that are generated within the components. This knowledge make it possible, for example, to style each `

` with class `term` but only when it occurs inside an element with ID `#mkwsTermlists`, so as to avoid inadvertently styling other elements using the same class in the non-MKWS parts of the page. The HTML structure is as follows. As in CSS, #ID indicates a unique identifier and .CLASS indicates an instance of a class. #mkwsSwitch a* #mkwsLang ( a | span )* #mkwsSearch form input#mkwsQuery type=text input#mkwsButton type=submit #mkwsBlanket (no contents -- used only for masking) #mkwsResults table tbody tr td #mkwsTermlists div.title div.facet* div.termtitle ( a span br )* td div#mkwsRanking form#mkwsSelect select#mkwsSort select#mkwsPerpage #mkwsPager #mkwsNavi #mkwsRecords div.record* span (for sequence number) a (for title) span (for other information such as author) div.details (sometimes) table tbody tr* th td #mkwsTargets #mkwsBytarget table thead tr* td* tbody tr* td* #mkwsStat span.head span.clients span.records - - - Copyright (C) 2013 by IndexData ApS,