= Nitro 0.6.0 Nitro is an efficient, yet simple engine for developing professional Web Applications using the Ruby language. Nitro aims to provide a robust infrastructure for scalable web applications that can be distributed over a server cluster. However, Nitro can also power simple web applications for deployment on intranets or even personal computers. Nitro integrates the powerful Og Object-Relational mapping library. == Features A short summary of the major features: * XML server pages (.xhtml) Nitro uses standard, dully xml compliant xhtml pages with logic code, thus combining the power of embededed Ruby (like erb, eruby) with the xml compliance of Amrita. Even though it is a 'Callback' style templating system it is flexible enough to run as 'Pipeline' style system if the developer prefers this mode of operation.

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1 ?> Version: #{version} * Shaders, XSLT templates Nitro features a fully programmable source transformation pipeline. A transformation stage in this pipeline is called a Shader. An example shader transforms an XHTML document with embeded ruby-code processing instructions to a Ruby method. Another shader might be an XSLT stage. Nitro promotes the usage of XSLT for web templates. The functional nature of XSL is ideal for the Web. Moreover, the engine efficiently precompiles the xsl transformation along with other transformations (for example localization) essentially providing a computationally free transformation step. * Multi phase evaluation Experimental, facilitates efficient HTTP1.1 caching. * Fragment Synthesis Nitro server pages can include fragments at 'Compile' time or at 'RunTime' time. * Minimum configuration Configuration files are kept to the absolute minimum. The target is to have no configuration files at all. * Object-Relational Mapping Nitro integrates the Og (ObjectGraph) object-relational mapping library. Og provides transparent serialization of object graphs to a RDBMS backend. Unlike other similar libraries Og maps standard Ruby objects to SQL tables and not vice versa. Og provides a meta language to describe the relations between objects, a flexible and intuitive api for querieng the database, raw access to the SQL language if needed (for example to fine tune the automatically generated SQL tables, or for custom queries), suports deserialization to Ruby objects or tuples, automatically generates join tables for many_to_many relations and provides a collection of usefull Mixins to synthesize common Entities. Og is a combination of the best features of Active Record and the former O-R mapping library included in Nitro (NDB). Adapters for PostgreSQL and MySQL are included. * Distributed State Nitro provides a powerfull distributed state mechanism that utilizes the DRb library. A typicall use of this infrastructure is to provide distributed sessions when running your application over a server cluster. Distributed sessions are fully transparent to the developer. * Request Filters The develpoper has full access to the request handling pipeline. Request filters are a powerfull mechanism for customized processing of special requests. Example filters are the autologin filter, a gzip filter etc. Moreover, Nitro provides the fine-grained filtering method pioneered by Rails where you can attach single methods, blocks, objects or modules, before, after or arrounf actions. * Hierarchical Caching Nitro provides a well designed and efficient caching mechanism. Caching will be provided at the following levels: * DB Cache * Object Cache (deserialized objects) * Fragment Caching (cache generated sub-parts of a page, or a page) * HTTP 1.1 Caching (downstream caching of whole pages) The engine calculates intra-page dependencies automatically. A variety of invalidation strategies can be implemented. * Support for 'nice' urls. Experimental. * Simple events manager. Experimental. * Advanced debuging features * When running in debug mode, all exceptions raise are logged to a special debug panel in the current page. Find out the offending file and line from the exception dump, fix the bug, refresh the page. * in-process console: inject an irb session to a running application server. You can use the irb console to investigate all variables and code in your running server process. * integrates the 'breakpoint' library by Florian Gross. The Breakpoint library provides the convenience of being able to inspect and modify state, diagnose bugs all via IRB by simply setting breakpoints in your applications by the call of a method. * Parts Parts are organized modules of web services. A Web Framework that integrates a large collection of parts (User management, Blog, Fora, CMS, Personalization, ..) will be released by Navel. Other libraries of parts are expected from the Ruby community when the Part API is finalized. * UI Components Nitro is distributed with a collection of usefull UI components to make form based application development easier (for example an efficient, database-aware Pager component). * Path overloading Experimental. * Localization Nitro supports efficient localization of web applications. == Download The latest version of Nitro can be found at * http://www.navel.gr/nitro Documentation for Nitro can be found at * http://www.navel.gr/nitro/doc == Requirements Nitro requires the following applications or libraries: * Ruby 1.8.1 and greater (http://www.ruby-lang.org) Version 1.8.2.preview2 is recomended * Apache 2.0 (http://www.apache.org) Will be optional in a future version. The following applications or libraries are optional: * PostgreSQL (http://www.postgres.org) Used for Database driven web applications. * MySQL (http://www.mysql.org) Used for Database driven web applications. * Ruby-psql (http://www.postgresql.jp/interfaces/ruby/archive/ruby-postgres-0.7.1.tar.gz) Ruby interface to the PostgreSQL RDBMS. * Ruby-mysql (http://tmtm.org/ja/ruby/mysql/README_en.html) Ruby interface to the MySQL RDBMS. * Ruby-XSLT (http://gregoire.lejeune.free.fr/ruby-xslt_0.4.0.tar.gz) Used for XSLT based templates. Please install the required applications and libraries before continuing with the installation of Nitro. == Instalation Nitro is distributed as a RubyGem. First of all make sure you have installed RubyGems on your system. Then run the following command: gem install nitro Then try to run the examples/tiny Example application. A tar.gz distribution is also available on http://www.navel.gr/nitro == Running the example applications * examples/tiny A simple application that requires no external applications $ cd nitro/examples/tiny $ vi conf/apache.conf edit user, group,DocumentRoot root as needed. $ ./ctl start this script starts the distributed session cluster, apache and the application server. browse http://127.0.0.1:8080 to stop the application execute: $ ./ctl stop * examples/simple A simple application to demonstrate xsl skins, entities, postback. $ cd nitro/examples/simple $ vi conf/apache.conf edit user, group,DocumentRoot root as needed. $ vi conf/config.rb edit the postgresql user and password if you wan to run this application with MySQL edit the configuration file to include { ... :backend => "mysql" ... } instead. run the following script to initialize the postgresql database used by the example $ ruby install.rb $ ./ctl start this script starts the distributed session cluster, apache and the application server. browse http://127.0.0.1:8080 to attach an irb console to the running server, execute from another shell: $ cd /examples/simple $ irb -r env.rb to stop the application execute: $ ./ctl stop == Debuging Nitro applications Have "tail -f" commands running on logs/app.log in your application directory. Nitro will automatically display debugging and runtime information to these files. Debugging info will also be shown in the browser when running in debug mode. == Description of contents bin Commands and wizards. examples/ Various examples. 'tiny' is a minimal example, 'blog' is a fully working and nice looking Blog implementation, 'og' contains some Og examples and 'flash' is an example for generating binary content for a Nitro response. lib/nitro Nitro library source files. lib/og Og library source files. lib/glue Common source files. test Unit and functional tests. == Support For any questions regarding Nitro, feel free to ask on the ruby-talk mailing list (which is mirrored to comp.lang.ruby) or contact mailto:gm@navel.gr. == Licence Copyright (c) 2004 Navel Ltd (http://www.navel.gr) Nitro (http://www.navel.gr/nitro) is copyrighted free software created and maintained by George Moschovitis (mailto:gm@navel.gr) and released under the standard BSD Licence. For details consult the file LICENCE.