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Dojo Toolkit
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<h2 id="overview">Overview</h2> <p>Dojo is a <a href="/facts/JavaScript/XhhIIEsl">JavaScript</a> framework targeting the many needs of large-scale client-side web development. For example, Dojo abstracts the differences among diverse browsers to provide APIs that will work on all of them (it can even run on the server under <a href="/facts/Node.js/FKzhV4Qa">Node.js</a>); it establishes a framework for defining modules of code and managing their interdependencies; it provides build tools for optimizing JavaScript and <a href="/facts/CSS/tA90XBQo">CSS</a>, generating documentation, and unit testing; it supports <a href="/facts/Internationalization_and_localization/IGkl9VBM">internationalization, localization</a>, and <a href="/facts/Web_accessibility/JsA6wN2l">accessibility</a>; and it provides a rich suite of commonly needed utility classes and user-interface widgets. </p><p>Dojo is completely <a href="/facts/Open-source_software/HzTaB8E9">open source</a>. The toolkit includes about three thousand JavaScript modules, in addition to images and other resources. </p><p>The Dojo Toolkit is organized in several parts: </p> <ul><li>dojo contains the core and most non-visual modules.</li> <li>dijit is a library of user-interface modules for widgets and layout.</li> <li>dojox holds assorted modules not yet considered stable enough to include in <i>dojo</i> or <i>dijit</i>.</li> <li>util includes build tools such as optimization, documentation, style-checking, and testing.</li></ul> <h2 id="features">Features</h2> <h3>Widgets</h3> <p>Dojo widgets are components — comprising <a href="/facts/JavaScript/XhhIIEsl">JavaScript</a> code, <a href="/facts/HTML/sSc3fT78">HTML</a> markup, and <a href="/facts/Cascading_Style_Sheets/tA90XBQo">CSS</a> style declarations — that provide multi-browser (not to be confused with <a href="/facts/Cross-browser/3pgytz0u">cross-browser</a>), interactive features: </p> <ul><li><a href="/facts/Menu_(computing)/zdKCgPGq">Menus</a>, <a href="/facts/Tab_(GUI)/YswKP5Mg">tabs</a>, and <a href="/facts/Tooltip/alzUJ5c2">tooltips</a></li> <li>Sortable tables</li> <li>Dynamic charts</li> <li>2D <a href="/facts/Vector_graphics/y8ok7M2P">vector drawings</a></li> <li>Animated effects—fades, wipes and slides—facilities for custom animation effects</li></ul> <h3>Asynchronous communication</h3> <p>One important feature of Ajax applications is asynchronous communication of the browser with the server: information is exchanged and the page's presentation is updated without a need for reloading the whole page. Traditionally, this is done with the JavaScript object <a href="/facts/XMLHttpRequest/3FHofhdx">XMLHttpRequest</a>. Dojo provides an abstracted wrapper (dojo.xhr) around various web browsers' implementations of XMLHttpRequest, and dojo.io also supports other transports (such as hidden <a href="/facts/Framing_(World_Wide_Web)/DRFQgsvr">IFrames</a>) and a variety of data formats. Using this approach, it is easy to have the data a user enters into a form sent to the server "behind the scenes"; the server can then reply with some JavaScript code that updates the presentation of the page.<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a> </p> <h3>Packaging system</h3> <p>Dojo provides a packaging system to facilitate modular development of functionality in individual packages and sub-packages; the base Dojo "<a href="/facts/Bootstrapping_(computing)/6dkM4EQv">bootstrap</a>" script initializes a set of hierarchical package namespaces — "io", "event", etc. — under a root "dojo" <a href="/facts/Namespace/9efXwMtV">namespace</a>. After initialization of the root namespace, any Dojo package can be loaded (via <a href="/facts/XMLHttpRequest/3FHofhdx">XMLHttpRequest</a> or other similar transport) by using utility functions supplied in the bootstrap. It is also possible to initialize additional namespaces within or parallel to the "dojo" namespace, allowing extensions of Dojo or the development of private Dojo-managed namespaces for third-party libraries and applications. </p><p>Dojo packages can consist of multiple files and can specify which files constitute the entire package. Any package or file can also specify a dependency on other packages or files; when the package is loaded, any dependencies it specifies will also be loaded. </p><p><a href="/facts/Workaround/UF6B69P4">Workarounds</a> for cross-domain loading of most Dojo packages are provided (though this requires a specialized build of Dojo). </p><p>Dojo also provides a mechanism for building "profiles"; the build system takes as input a list of packages, and uses <a href="/facts/Rhino_(JavaScript_engine)/yNRIqPeo">Rhino</a> to create a single compressed JavaScript file containing those packages and all their dependencies. This allows all necessary code to be loaded and initialized at once, and permits <a href="/facts/Web_cache/DqIBcWem">caching</a> of the code (most <a href="/facts/Web_browser/2pfyymLs">web browsers</a> do not cache files loaded via XMLHttpRequest). Pre-built profiles for some common use cases are available for download from the same location as the full toolkit. </p> <h3>Client-side data storage</h3> <p>Dojo has support functions for reading and writing <a href="/facts/HTTP_cookie/o1laXyng">cookies</a>. It also previously supported a local, client-side storage abstraction named Dojo Storage. </p><p>Dojo Storage allows web applications to store data on the client-side, persistently and securely and with a user's permission. When included in a web page, Dojo Storage determines the best method for persistently storing information. It works across existing web browsers, including <a href="/facts/Internet_Explorer/uL8a4Y5l">Internet Explorer</a>, <a href="/facts/Firefox/xez2zv8H">Firefox</a>, and <a href="/facts/Safari_(web_browser)/9R8v7tNl">Safari</a>. Firefox 2 uses native browser persistence; on other browsers, it uses a hidden <a href="/facts/Adobe_Flash/3Lrp9JuH">Flash</a> applet. With Flash 6+ have previously been installed on about 95% of computers connected to the web,<a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a> this previously made the storage mechanism accessible for much of the web's installed base. For a web application loaded from the file system, i.e., from a file:// URL, Dojo Storage will transparently use <a href="/facts/XPCOM/42dTP1Xc">XPCOM</a> on Firefox and <a href="/facts/ActiveX/xJb7t7Eh">ActiveX</a> on Internet Explorer to persist information. The programmer using Dojo Storage is abstracted from the storage mechanism used and is presented with a simple <a href="/facts/Hash_table/Ht4ptDPF">hash table</a> abstraction, with methods such as put() and get(). Dojo Storage is not supported in versions later than the 1.3 release. </p> <h3>Server-side data storage</h3> <p>As of January 2007, Dojo includes the following example <a href="/facts/Server-side/JqukWyaA">server-side</a> datastore implementations in the <i>dojo.data</i> namespace:<a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a> </p> <ul><li>CsvStore: a read-only store that reads tabular data from <a href="/facts/Comma-separated_values/dv1pSR1r">comma-separated values</a> files</li> <li>OpmlStore: a read-only store that reads hierarchical data from <a href="/facts/OPML/rUQ5TtLk">OPML</a> format files</li> <li>YahooStore: a read-only store that fetches search results from the <a href="/facts/Yahoo!_Search/vpTvHcV1">Yahoo! Search</a> web service</li> <li>DeliciousStore: a read-only store that fetches bookmarks from the <a href="/facts/Del.icio.us/J0kjpxfL">del.icio.us</a> web service</li> <li>RdfStore: a read-write store that uses <a href="/facts/SPARQL/XPP7pFDJ">SPARQL</a> to talk to <a href="/facts/Resource_Description_Framework/WMufyukm">RDF</a> data servers including, for example, the Rhizome RDF application server.</li></ul> <h3>Support for Adobe Integrated Runtime (AIR)</h3> <p>Dojo can be used in <a href="/facts/JavaScript/XhhIIEsl">JavaScript</a>-based <a href="/facts/Adobe_Integrated_Runtime/oV2TPXJP">Adobe AIR</a> applications. It has been modified to meet AIR's security requirements. </p><p>SitePen, a Dojo consulting company, has made an Adobe AIR application called "Dojo Toolbox" using Dojo. It includes an API viewer and a GUI to Dojo's build system. Normally, the build system is run from within Rhino, but in this AIR application the build system can be run from AIR, without the use of Java.<a class="footnote-ref" id="fnref:9" href="#fn:9"><sup>9</sup></a> </p> <h2 id="criticisms">Criticisms</h2> <h3>Loading</h3> <p>Earlier versions of Dojo had a reputation for being bulky and slow to load.<a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a> It also required extra work to load Dojo across domains, e.g., from a <a href="/facts/Content_delivery_network/SVuID7jd">CDN</a>. Addressing these problems was the major goal of Dojo 1.7, which introduced <a href="/facts/Asynchronous_module_definition/zsIWNayD">asynchronous module definition</a> (AMD) and a "nano" loader.<a class="footnote-ref" id="fnref:11" href="#fn:11"><sup>11</sup></a> </p> <h3>Documentation</h3> <p>Dojo has long been criticized for its incomplete, scattered, and outdated documentation. Recognizing this, the developers made huge improvements in the documentation for the 1.8 release, including new tutorials, an API browser, filling in the missing pieces, and updating most examples to <a href="/facts/Asynchronous_module_definition/zsIWNayD">AMD</a> style.<a class="footnote-ref" id="fnref:12" href="#fn:12"><sup>12</sup></a><a class="footnote-ref" id="fnref:13" href="#fn:13"><sup>13</sup></a> </p><p>A number of books have been written about Dojo, but all based upon Dojo 1.3 or earlier, now several years out of date. Since these predate AMD support and its accompanying reorganization, examples in these books almost invariably rely on things that are now deprecated and no longer best practice. Most authors are waiting for Dojo 2.0 before publishing anything new. <a class="footnote-ref" id="fnref:14" href="#fn:14"><sup>14</sup></a> </p> <h3>Learning curve</h3> <p>Many have commented that Dojo seems difficult to learn and get started with, especially in comparison with the more popular <a href="/facts/JQuery/YIqFG0ww">jQuery</a>.<a class="footnote-ref" id="fnref:15" href="#fn:15"><sup>15</sup></a><a class="footnote-ref" id="fnref:16" href="#fn:16"><sup>16</sup></a> </p><p>Dojo co-creator Dylan Schiemann acknowledges this as a consequence of their different scopes: "It's certainly easier to learn something that's smaller than something that does more, but our avid users are quick to point out that a bit more learning up front saves them countless hours for things that Dojo makes easy."<a class="footnote-ref" id="fnref:17" href="#fn:17"><sup>17</sup></a> </p> <h3>API stability</h3> <p>Early users faced a difficult transition to the 1.0 release after the toolkit was totally rewritten.<a class="footnote-ref" id="fnref:18" href="#fn:18"><sup>18</sup></a> The move to AMD in recent versions has been similarly problematic.<a class="footnote-ref" id="fnref:19" href="#fn:19"><sup>19</sup></a> Dojo has taken great pains to maintain backward compatibility despite its rapid evolution, with a large portion of the current API deprecated but still maintained, but users have often found that upgrades did not go as smoothly as hoped. </p><p>Dojo 2.0 release removed much of the deprecated API and switched from JavaScript to TypeScript. </p> <h2 id="see-also">See also</h2> <ul> <li>Free and open-source software portal</li></ul> <ul><li><a href="/facts/Comparison_of_JavaScript_frameworks/74bS48ah">Comparison of JavaScript frameworks</a></li> <li><a href="/facts/JavaScript_framework/8f1CVHDX">JavaScript framework</a></li> <li><a href="/facts/JavaScript_library/vjUJ5DGC">JavaScript library</a></li></ul> <h2 id="further-reading">Further reading</h2> <ul><li>Orchard, Leslie M. (November 24, 2008). <a href="http://www.wrox.com/WileyCDA/WroxTitle/Concise-Guide-to-Dojo.productCd-0470452021.html"><i>Concise Guide to Dojo</i></a> (1st ed.). <a href="/facts/Wrox_Press/4pfQvkJF">Wrox Press</a>. p. 264. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-470-45202-8.</li> <li>Russell, Matthew A. (June 24, 2008). <a href="https://archive.org/details/developingwithdo00matt"><i>Dojo: The Definitive Guide</i></a> (1st ed.). <a href="/facts/O%2527Reilly_Media/Fr3Kv7sm">O'Reilly Media</a>. p. 500. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-596-51648-2.</li> <li>Riecke, Craig; Gill, Rawld; Russell, Alex (June 18, 2008). <a href="https://archive.org/details/masteringdojojav0000gill"><i>Mastering Dojo: JavaScript and Ajax Tools for Great Web Experiences</i></a> (1st ed.). <a href="/facts/Pragmatic_Bookshelf/rQeDXFMK">Pragmatic Bookshelf</a>. p. 568. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-1-934356-11-1.</li> <li>Holzner, Steven (December 14, 2008). <a href="http://www.peachpit.com/store/product.aspx?isbn=0321605128"><i>The Dojo Toolkit: Visual QuickStart Guide</i></a> (1st ed.). <a href="/facts/Peachpit_Press/j9mbEWJB">Peachpit Press</a>. p. 208. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-321-60512-2.</li> <li>Zammetti, Frank (September 19, 2008). <a href="http://www.apress.com/9781430210665"><i>Practical Dojo Projects</i></a> (1st ed.). <a href="/facts/Apress/pxdyEeD3">Apress</a>. p. 500. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-1-4302-1066-5.</li> <li>Hayes, Kyle (November 17, 2009). <a href="https://web.archive.org/web/20100422233232/http://www.friendsofed.com/book.html?isbn=9781430225218"><i>Getting StartED with Dojo JavaScript Toolkit</i></a> (1st ed.). <a href="/facts/Friends_of_Ed/pxdyEeD3">Friends of Ed</a>. p. 350. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-1-4302-2521-8. Archived from <a href="http://www.friendsofed.com/book.html?isbn=9781430225218">the original</a> on April 22, 2010. Retrieved August 15, 2009.</li> <li>Svensson, Peter (November 24, 2008). <a href="http://www.packtpub.com/tutorial-for-building-interactive-interfaces-with-dojo/book"><i>Learning Dojo</i></a> (1st ed.). <a href="/facts/Packt/eT0RTSSK">Packt Publishing</a>. p. 264. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-1-84719-268-4.</li> <li>Harmon, James E. (June 21, 2008). <a href="http://www.informit.com/store/product.aspx?isbn=0132358042"><i>Dojo: Using the Dojo JavaScript Library to Build Ajax Applications</i></a> (1st ed.). <a href="/facts/Addison-Wesley_Professional/A7UFATEG">Addison-Wesley Professional</a>. p. 336. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-13-235804-0.</li> <li>Orchard, Leslie M.; Pehlivanian, Ara; Koon, Scott; Jones, Harley (August 31, 2009). <a href="https://web.archive.org/web/20110706050324/http://www.wrox.com/WileyCDA/WroxTitle/Professional-JavaScript-Frameworks-Prototype-YUI-ExtJS-Dojo-and-MooTools.productCd-047038459X.html"><i>Professional JavaScript Frameworks: Prototype,YUI, ExtJS, Dojo and MooTools</i></a> (1st ed.). <a href="/facts/Wrox_Press/4pfQvkJF">Wrox Press</a>. p. 888. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-470-38459-6. Archived from <a href="http://www.wrox.com/WileyCDA/WroxTitle/Professional-JavaScript-Frameworks-Prototype-YUI-ExtJS-Dojo-and-MooTools.productCd-047038459X.html">the original</a> on July 6, 2011. Retrieved August 15, 2009.</li></ul> <h2 id="external-links">External links</h2> <ul><li><a href="http://dojotoolkit.org/">Dojo toolkit website</a></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>"A Brief History of Dojo — The Dojo Toolkit - Reference Guide". dojotoolkit.org. Retrieved January 16, 2024. <a href="https://dojotoolkit.org/reference-guide/1.10/quickstart/introduction/history.html" target="_blank">https://dojotoolkit.org/reference-guide/1.10/quickstart/introduction/history.html</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>"Dojo Toolkit License". Dojo Toolkit. Retrieved April 17, 2017. <a href="http://dojotoolkit.org/license.html" target="_blank">http://dojotoolkit.org/license.html</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>"jQuery Foundation and Dojo Foundation to Merge". Official jQuery Blog. September 1, 2015. Retrieved July 2, 2018. <a href="https://blog.jquery.com/2015/09/01/jquery-foundation-and-dojo-foundation-to-merge/" target="_blank">https://blog.jquery.com/2015/09/01/jquery-foundation-and-dojo-foundation-to-merge/</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>"jQuery Foundation and Dojo Foundation to Merge". PRWeb. July 1, 2015. Retrieved July 2, 2018. <a href="https://www.prweb.com/releases/jquery_foundation_and_dojo_foundation_to_merge/prweb12931885.htm" target="_blank">https://www.prweb.com/releases/jquery_foundation_and_dojo_foundation_to_merge/prweb12931885.htm</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>"Announcing the JS Foundation!". SitePen. October 17, 2016. Retrieved July 2, 2018. <a href="https://www.sitepen.com/blog/2016/10/17/announcing-the-js-foundation/" target="_blank">https://www.sitepen.com/blog/2016/10/17/announcing-the-js-foundation/</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>"What is Asynchronous JavaScript and XML (AJAX)?". TheServerSide.com. Retrieved July 4, 2023. <a href="https://www.theserverside.com/definition/Ajax-Asynchronous-JavaScript-and-XML" target="_blank">https://www.theserverside.com/definition/Ajax-Asynchronous-JavaScript-and-XML</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>"Adobe Flash Player Version Penetration". Adobe website. <a href="http://www.adobe.com/products/player_census/flashplayer/version_penetration.html" target="_blank">http://www.adobe.com/products/player_census/flashplayer/version_penetration.html</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>"Dojo Data". January 11, 2007. Archived from the original on February 13, 2007. Retrieved February 3, 2007. <a href="https://web.archive.org/web/20070213220902/http://manual.dojotoolkit.org/Book105" target="_blank">https://web.archive.org/web/20070213220902/http://manual.dojotoolkit.org/Book105</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>"Development and JavaScript Blog". <a href="http://www.sitepen.com/blog/2008/09/09/inside-the-dojo-toolbox/" target="_blank">http://www.sitepen.com/blog/2008/09/09/inside-the-dojo-toolbox/</a> <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> <li id="fn:10"><p>"An Interview with Dojo Toolkit Creator Dylan Schiemann". Nettuts+. August 16, 2012. Retrieved November 21, 2012. <a href="http://net.tutsplus.com/articles/interviews/an-interview-with-dojo-toolkit-creator-dylan-schiemann/" target="_blank">http://net.tutsplus.com/articles/interviews/an-interview-with-dojo-toolkit-creator-dylan-schiemann/</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></p></li> <li id="fn:11"><p>"Dojo 1.7 Released!". Dojo Toolkit Blog. January 1, 2011. Retrieved November 21, 2012. <a href="http://dojotoolkit.org/blog/dojo-1-7-released" target="_blank">http://dojotoolkit.org/blog/dojo-1-7-released</a> <a href="#fnref:11" class="footnote-back-ref">↩</a></p></li> <li id="fn:12"><p>"What's coming in Dojo 1.8". Dojo Toolkit Blog. February 9, 2012. Retrieved November 21, 2012. <a href="http://dojotoolkit.org/blog/whats-coming-in-dojo-1-8" target="_blank">http://dojotoolkit.org/blog/whats-coming-in-dojo-1-8</a> <a href="#fnref:12" class="footnote-back-ref">↩</a></p></li> <li id="fn:13"><p>"what is the raison detre for dojo 2.0". dojo-contributors. October 11, 2012. Retrieved November 29, 2012.Archived 2017-12-01 at the Wayback Machine <a href="http://grokbase.com/p/dojo/dojo-contributors/12abyztv9p/" target="_blank">http://grokbase.com/p/dojo/dojo-contributors/12abyztv9p/</a> <a href="#fnref:13" class="footnote-back-ref">↩</a></p></li> <li id="fn:14"><p>Schiemann, Dylan (April 30, 2012). "jQuery and the long term viability of Dojo". Dojo-interest. Archived from the original on October 29, 2014. Retrieved November 29, 2012. <a href="https://web.archive.org/web/20141029133029/http://mail.dojotoolkit.org/pipermail/dojo-interest/2012-April/066087.html" target="_blank">https://web.archive.org/web/20141029133029/http://mail.dojotoolkit.org/pipermail/dojo-interest/2012-April/066087.html</a> <a href="#fnref:14" class="footnote-back-ref">↩</a></p></li> <li id="fn:15"><p>"Criticism of Dojo?". Seven Foot Tall Cactus. August 17, 2012. Archived from the original on October 26, 2012. Retrieved November 21, 2012. <a href="https://web.archive.org/web/20121026095745/http://blog.kitsonkelly.com/2012/08/criticism-of-dojo/" target="_blank">https://web.archive.org/web/20121026095745/http://blog.kitsonkelly.com/2012/08/criticism-of-dojo/</a> <a href="#fnref:15" class="footnote-back-ref">↩</a></p></li> <li id="fn:16"><p>"Dojo or JQuery". NotADojoGuru. April 6, 2012. Retrieved November 21, 2012. <a href="http://notadojoguru.wordpress.com/2012/04/06/dojo-or-jquery/" target="_blank">http://notadojoguru.wordpress.com/2012/04/06/dojo-or-jquery/</a> <a href="#fnref:16" class="footnote-back-ref">↩</a></p></li> <li id="fn:17"><p>"An Interview with Dojo Toolkit Creator Dylan Schiemann". Nettuts+. August 16, 2012. Retrieved November 21, 2012. <a href="http://net.tutsplus.com/articles/interviews/an-interview-with-dojo-toolkit-creator-dylan-schiemann/" target="_blank">http://net.tutsplus.com/articles/interviews/an-interview-with-dojo-toolkit-creator-dylan-schiemann/</a> <a href="#fnref:17" class="footnote-back-ref">↩</a></p></li> <li id="fn:18"><p>"what is the raison detre for dojo 2.0". dojo-contributors. October 11, 2012. Retrieved November 29, 2012.Archived 2017-12-01 at the Wayback Machine <a href="http://grokbase.com/p/dojo/dojo-contributors/12abyztv9p/" target="_blank">http://grokbase.com/p/dojo/dojo-contributors/12abyztv9p/</a> <a href="#fnref:18" class="footnote-back-ref">↩</a></p></li> <li id="fn:19"><p>"Dojo or JQuery". NotADojoGuru. April 6, 2012. Retrieved November 21, 2012. <a href="http://notadojoguru.wordpress.com/2012/04/06/dojo-or-jquery/" target="_blank">http://notadojoguru.wordpress.com/2012/04/06/dojo-or-jquery/</a> <a href="#fnref:19" class="footnote-back-ref">↩</a></p></li> </ol>