| 1 | joko | 1.1 | NAME | 
| 2 |  |  | Data::Storage - Interface for accessing various Storage implementations | 
| 3 |  |  | for Perl in an independent way | 
| 4 |  |  |  | 
| 5 |  |  | SYNOPSIS | 
| 6 |  |  | ... the basic way: | 
| 7 |  |  |  | 
| 8 |  |  | ... via inheritance: | 
| 9 |  |  |  | 
| 10 |  |  | use Data::Storage; | 
| 11 |  |  | my $proxyObj = new HttpProxy; | 
| 12 |  |  | $proxyObj->{url} = $url; | 
| 13 |  |  | $proxyObj->{payload} = $content; | 
| 14 |  |  | $self->{storage}->insert($proxyObj); | 
| 15 |  |  |  | 
| 16 |  |  | use Data::Storage; | 
| 17 |  |  | my $proxyObj = HttpProxy->new( | 
| 18 |  |  | url => $url, | 
| 19 |  |  | payload => $content, | 
| 20 |  |  | ); | 
| 21 |  |  | $self->{storage}->insert($proxyObj); | 
| 22 |  |  |  | 
| 23 |  |  | NOTE | 
| 24 |  |  |  | 
| 25 |  |  | This module heavily relies on DBI and Tangram, but adds a lot of | 
| 26 |  |  | additional bugs and quirks. Please look at their documentation and this | 
| 27 |  |  | code for additional information. | 
| 28 |  |  |  | 
| 29 |  |  | DESCRIPTION | 
| 30 |  |  | Data::Storage is module for a accessing various "data structures" stored | 
| 31 |  |  | inside various "data containers". It sits on top of DBI and/or Tangram. | 
| 32 |  |  |  | 
| 33 |  |  | AUTHORS / COPYRIGHT | 
| 34 |  |  | The Data::Storage module is Copyright (c) 2002 Andreas Motl. All rights | 
| 35 |  |  | reserved. | 
| 36 |  |  |  | 
| 37 |  |  | You may distribute it under the terms of either the GNU General Public | 
| 38 |  |  | License or the Artistic License, as specified in the Perl README file. | 
| 39 |  |  |  | 
| 40 |  |  | ACKNOWLEDGEMENTS | 
| 41 |  |  | Larry Wall and the "perl5-porters" for Perl, Tim Bunce for DBI, | 
| 42 |  |  | Jean-Louis Leroy for Tangram and Set::Object, Sam Vilain for | 
| 43 |  |  | Class::Tangram. | 
| 44 |  |  |  | 
| 45 |  |  | SUPPORT / WARRANTY | 
| 46 |  |  | Data::Storage is free software. IT COMES WITHOUT WARRANTY OF ANY KIND. | 
| 47 |  |  |  | 
| 48 |  |  | TODO | 
| 49 |  |  | Handle the following errors/cases: | 
| 50 |  |  |  | 
| 51 |  |  | "DBI-Error [Tangram]: DBD::mysql::st execute failed: Unknown column 't1.requestdump' in 'field list'" | 
| 52 |  |  |  | 
| 53 |  |  | ... occours when operating on object-attributes not introduced yet: | 
| 54 |  |  | this should be detected and appended/replaced through: | 
| 55 |  |  | "Schema-Error detected, maybe (just) an inconsistency. | 
| 56 |  |  | Please check if your declaration in schema-module "a" matches structure in database "b" or try to run" | 
| 57 |  |  | db_setup.pl --dbkey=import --action=deploy | 
| 58 |  |  |  | 
| 59 |  |  | Compare schema (structure diff) with database ... | 
| 60 |  |  |  | 
| 61 |  |  | ... when issuing "db_setup.pl --dbkey=import --action=deploy" | 
| 62 |  |  | on a database with an already deployed schema, use an additional "--update" then | 
| 63 |  |  | to lift the schema inside the database to the current declared schema. | 
| 64 |  |  | You will have to approve removals and changes on field-level while | 
| 65 |  |  | new objects and new fields are introduced silently without any interaction needed. | 
| 66 |  |  | In future versions there may be additional options to control silent processing of | 
| 67 |  |  | removals and changes. | 
| 68 |  |  | See this CRUD-table applying to the actions occouring on Classes and Class variables when deploying schemas, | 
| 69 |  |  | don't mix this up with CRUD-actions on Objects, these are already handled by (e.g.) Tangram itself. | 
| 70 |  |  | Classes: | 
| 71 |  |  | C create    ->  yes, handled automatically | 
| 72 |  |  | R retrieve  ->  no, not subject of this aspect since it is about deployment only | 
| 73 |  |  | U update    ->  yes, automatically for Class meta-attributes, yes/no for Class variables (look at the rules down here) | 
| 74 |  |  | D delete    ->  yes, just by user-interaction | 
| 75 |  |  | Class variables: | 
| 76 |  |  | C create    ->  yes, handled automatically | 
| 77 |  |  | R retrieve  ->  no, not subject of this aspect since it is about deployment only | 
| 78 |  |  | U update    ->  yes, just by user-interaction; maybe automatically if it can be determined that data wouldn't be lost | 
| 79 |  |  | D delete    ->  yes, just by user-interaction | 
| 80 |  |  | It's all about not to be able to loose data simply while this is in alpha stage. | 
| 81 |  |  |  | 
| 82 |  |  | Introduce some features: | 
| 83 |  |  |  | 
| 84 |  |  | Get this stuff together with UML (Unified Modeling Language) and/or standards from ODMG. | 
| 85 |  |  | Make it possible to load/save schemas in XMI (XML Metadata Interchange), | 
| 86 |  |  | which seems to be most commonly used today, perhaps handle objects with OIFML. | 
| 87 |  |  | Integrate/bundle this with a web-/html-based UML modeling tool or | 
| 88 |  |  | some other interesting stuff like the "Co-operative UML Editor" from Uni Darmstadt. (web-/java-based) | 
| 89 |  |  | Enable Round Trip Engineering. Keep code and diagrams in sync. Don't annoy/bother the programmer. | 
| 90 |  |  |  | 
| 91 |  |  | Links: | 
| 92 |  |  |  | 
| 93 |  |  | UML 1.3 Spec: http://cgi.omg.org/cgi-bin/doc?ad/99-06-08.pdf | 
| 94 |  |  | XMI 1.1 Spec: http://cgi.omg.org/cgi-bin/doc?ad/99-10-02.pdf | 
| 95 |  |  | XMI 2.0 Spec: http://cgi.omg.org/docs/ad/01-06-12.pdf | 
| 96 |  |  | ODMG: http://odmg.org/ | 
| 97 |  |  | OIFML: http://odmg.org/library/readingroom/oifml.pdf | 
| 98 |  |  | Co-operative UML Editor: http://www.darmstadt.gmd.de/concert/activities/internal/umledit.html | 
| 99 |  |  |  | 
| 100 |  |  | further readings: | 
| 101 |  |  | http://www.google.com/search?q=web+based+uml+editor&hl=en&lr=&ie=UTF-8&oe=UTF-8&start=10&sa=N | 
| 102 |  |  | http://www.fernuni-hagen.de/DVT/Aktuelles/01FHHeidelberg.pdf | 
| 103 |  |  | http://www.enhyper.com/src/documentation/ | 
| 104 |  |  | http://cis.cs.tu-berlin.de/Dokumente/Diplomarbeiten/2001/skinner.pdf | 
| 105 |  |  | http://citeseer.nj.nec.com/vilain00diagrammatic.html | 
| 106 |  |  | http://archive.devx.com/uml/articles/Smith01/Smith01-3.asp | 
| 107 |  |  |  | 
| 108 |  |  | maybe useful for / to be integrated with: | 
| 109 |  |  | ArapXML: http://xml.coverpages.org/ni2001-09-24-b.html |