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1 <HTML>
2 <HEAD>
3 <TITLE>Data::Storage</TITLE>
4 <LINK REV="made" HREF="mailto:">
5 </HEAD>
6
7 <BODY>
8
9 <A NAME="__index__"></A>
10 <!-- INDEX BEGIN -->
11
12 <UL>
13
14 <LI><A HREF="#name">NAME</A></LI>
15 <LI><A HREF="#aims">AIMS</A></LI>
16 <LI><A HREF="#synopsis">SYNOPSIS</A></LI>
17 <UL>
18
19 <LI><A HREF="#basic access">BASIC ACCESS</A></LI>
20 <LI><A HREF="#advanced access">ADVANCED ACCESS</A></LI>
21 <LI><A HREF="#synchronization">SYNCHRONIZATION</A></LI>
22 <LI><A HREF="#note">NOTE</A></LI>
23 </UL>
24
25 <LI><A HREF="#requirements">REQUIREMENTS</A></LI>
26 <LI><A HREF="#description">DESCRIPTION</A></LI>
27 <UL>
28
29 <LI><A HREF="#data::storage">Data::Storage</A></LI>
30 <LI><A HREF="#why">Why?</A></LI>
31 <LI><A HREF="#what else">What else?</A></LI>
32 </UL>
33
34 <LI><A HREF="#authors / copyright">AUTHORS / COPYRIGHT</A></LI>
35 <LI><A HREF="#acknowledgements">ACKNOWLEDGEMENTS</A></LI>
36 <LI><A HREF="#support / warranty">SUPPORT / WARRANTY</A></LI>
37 <LI><A HREF="#todo">TODO</A></LI>
38 <UL>
39
40 <LI><A HREF="#bugs">BUGS</A></LI>
41 <LI><A HREF="#features">FEATURES</A></LI>
42 <UL>
43
44 <LI><A HREF="#links / references">LINKS / REFERENCES</A></LI>
45 </UL>
46
47 </UL>
48
49 </UL>
50 <!-- INDEX END -->
51
52 <HR>
53 <P>
54 <HR>
55 <H1><A NAME="name">NAME</A></H1>
56 <PRE>
57 Data::Storage - Interface for accessing various Storage implementations for Perl in an independent way</PRE>
58 <P>
59 <HR>
60 <H1><A NAME="aims">AIMS</A></H1>
61 <PRE>
62 - should encapsulate Tangram, DBI, DBD::CSV and LWP:: to access them in an unordinary (more convenient) way ;)
63 - introduce a generic layered structure, refactor *SUBLAYER*-stuff, make (e.g.) this possible:
64 Perl Data::Storage[DBD::CSV] -&gt; Perl LWP:: -&gt; Internet HTTP/FTP/* -&gt; Host Daemon -&gt; csv-file
65 - provide generic synchronization mechanisms across arbitrary/multiple storages based on ident/checksum
66 maybe it's possible to have schema-, structural- and semantical modifications synchronized???</PRE>
67 <P>
68 <HR>
69 <H1><A NAME="synopsis">SYNOPSIS</A></H1>
70 <P>
71 <H2><A NAME="basic access">BASIC ACCESS</A></H2>
72 <P>
73 <H2><A NAME="advanced access">ADVANCED ACCESS</A></H2>
74 <PRE>
75 ... via inheritance:
76 </PRE>
77 <PRE>
78
79 use Data::Storage;
80 my $proxyObj = new HttpProxy;
81 $proxyObj-&gt;{url} = $url;
82 $proxyObj-&gt;{payload} = $content;
83 $self-&gt;{storage}-&gt;insert($proxyObj);</PRE>
84 <PRE>
85
86 use Data::Storage;
87 my $proxyObj = HttpProxy-&gt;new(
88 url =&gt; $url,
89 payload =&gt; $content,
90 );
91 $self-&gt;{storage}-&gt;insert($proxyObj);</PRE>
92 <P>
93 <H2><A NAME="synchronization">SYNCHRONIZATION</A></H2>
94 <PRE>
95 my $nodemapping = {
96 'LangText' =&gt; 'langtexts.csv',
97 'Currency' =&gt; 'currencies.csv',
98 'Country' =&gt; 'countries.csv',
99 };</PRE>
100 <PRE>
101 my $propmapping = {
102 'LangText' =&gt; [
103 [ 'source:lcountrykey' =&gt; 'target:country' ],
104 [ 'source:lkey' =&gt; 'target:key' ],
105 [ 'source:lvalue' =&gt; 'target:text' ],
106 ],
107 'Currency' =&gt; [
108 [ 'source:ckey' =&gt; 'target:key' ],
109 [ 'source:cname' =&gt; 'target:text' ],
110 ],
111 'Country' =&gt; [
112 [ 'source:ckey' =&gt; 'target:key' ],
113 [ 'source:cname' =&gt; 'target:text' ],
114 ],
115 };</PRE>
116 <PRE>
117 s ub syncResource {</PRE>
118 <PRE>
119 my $self = shift;
120 my $node_source = shift;
121 my $mode = shift;
122 my $opts = shift;
123 </PRE>
124 <PRE>
125
126 $mode ||= '';
127 $opts-&gt;{erase} ||= 0;</PRE>
128 <PRE>
129
130 $logger-&gt;info( __PACKAGE__ . &quot;-&gt;syncResource( node_source $node_source mode $mode erase $opts-&gt;{erase} )&quot;);</PRE>
131 <PRE>
132
133 # resolve metadata for syncing requested resource
134 my $node_target = $nodemapping-&gt;{$node_source};
135 my $mapping = $propmapping-&gt;{$node_source};</PRE>
136 <PRE>
137
138 if (!$node_target || !$mapping) {
139 # loggger.... &quot;no target, sorry!&quot;
140 print &quot;error while resolving resource metadata&quot;, &quot;\n&quot;;
141 return;
142 }</PRE>
143 <PRE>
144
145 if ($opts-&gt;{erase}) {
146 $self-&gt;_erase_all($node_source);
147 }</PRE>
148 <PRE>
149
150 # create new sync object
151 my $sync = Data::Transfer::Sync-&gt;new(
152 storages =&gt; {
153 L =&gt; $self-&gt;{bizWorks}-&gt;{backend},
154 R =&gt; $self-&gt;{bizWorks}-&gt;{resources},
155 },
156 id_authorities =&gt; [qw( L ) ],
157 checksum_authorities =&gt; [qw( L ) ],
158 write_protected =&gt; [qw( R ) ],
159 verbose =&gt; 1,
160 );</PRE>
161 <PRE>
162
163 # sync
164 # todo: filter!?
165 $sync-&gt;syncNodes( {
166 direction =&gt; $mode, # | +PUSH | +PULL | -FULL | +IMPORT | -EXPORT
167 method =&gt; 'checksum', # | -timestamp | -manual
168 source =&gt; &quot;L:$node_source&quot;,
169 source_ident =&gt; 'storage_method:id',
170 source_exclude =&gt; [qw( id cs )],
171 target =&gt; &quot;R:$node_target&quot;,
172 target_ident =&gt; 'property:oid',
173 mapping =&gt; $mapping,
174 } );</PRE>
175 <PRE>
176 }</PRE>
177 <P>
178 <H2><A NAME="note">NOTE</A></H2>
179 <PRE>
180 This module heavily relies on DBI and Tangram, but adds a lot of additional bugs and quirks.
181 Please look at their documentation and/or this code for additional information.</PRE>
182 <P>
183 <HR>
184 <H1><A NAME="requirements">REQUIREMENTS</A></H1>
185 <PRE>
186 For full functionality:
187 DBI from CPAN
188 DBD::mysql from CPAN
189 Tangram 2.04 from CPAN (hmmm, 2.04 won't do in some cases)
190 Tangram 2.05 from <A HREF="http://">http://</A>... (2.05 seems okay but there are also additional patches from our side)
191 Class::Tangram from CPAN
192 DBD::CSV from CPAN
193 MySQL::Diff from <A HREF="http://adamspiers.org/computing/mysqldiff/">http://adamspiers.org/computing/mysqldiff/</A>
194 ... and all their dependencies</PRE>
195 <P>
196 <HR>
197 <H1><A NAME="description">DESCRIPTION</A></H1>
198 <P>
199 <H2><A NAME="data::storage">Data::Storage</A></H2>
200 <PRE>
201 Data::Storage is a module for accessing various &quot;data structures / kinds of structured data&quot; stored inside
202 various &quot;data containers&quot;.
203 We tried to use the AdapterPattern to implement a wrapper-layer around known CPAN modules.
204 (e.g. DBI, Tangram, XML::Simple)
205 References:
206 - <A HREF="http://c2.com/cgi/wiki?AdapterPattern">http://c2.com/cgi/wiki?AdapterPattern</A>
207 - <A HREF="http://home.earthlink.net/~huston2/dp/adapter.html">http://home.earthlink.net/~huston2/dp/adapter.html</A></PRE>
208 <P>
209 <H2><A NAME="why">Why?</A></H2>
210 <PRE>
211 You will get a better code-structure (not bad for later maintenance) in growing Perl code projects,
212 especially when using multiple database connections at the same time.
213 You will be able to switch between different _kinds_ of implementations used for storing data.
214 Your code will use the very same API to access these storage layers.
215 ... implementation has to be changed for now
216 Maybe you will be able to switch &quot;on-the-fly&quot; without changing any bits in code in the future....
217 ... but that's not the focus</PRE>
218 <P>
219 <H2><A NAME="what else">What else?</A></H2>
220 <PRE>
221 Having this, we were able to do implement a generic data synchronization module more easy,
222 please look at Data::Transfer.</PRE>
223 <P>
224 <HR>
225 <H1><A NAME="authors / copyright">AUTHORS / COPYRIGHT</A></H1>
226 <PRE>
227 The Data::Storage module is Copyright (c) 2002 Andreas Motl.
228 All rights reserved.
229 You may distribute it under the terms of either the GNU General Public
230 License or the Artistic License, as specified in the Perl README file.</PRE>
231 <P>
232 <HR>
233 <H1><A NAME="acknowledgements">ACKNOWLEDGEMENTS</A></H1>
234 <PRE>
235 Larry Wall for Perl, Tim Bunce for DBI, Jean-Louis Leroy for Tangram and Set::Object,
236 Sam Vilain for Class::Tangram, Jochen Wiedmann and Jeff Zucker for DBD::CSV &amp; Co.,
237 Adam Spiers for MySQL::Diff and all contributors.</PRE>
238 <P>
239 <HR>
240 <H1><A NAME="support / warranty">SUPPORT / WARRANTY</A></H1>
241 <PRE>
242 Data::Storage is free software. IT COMES WITHOUT WARRANTY OF ANY KIND.</PRE>
243 <P>
244 <HR>
245 <H1><A NAME="todo">TODO</A></H1>
246 <P>
247 <H2><A NAME="bugs">BUGS</A></H2>
248 <P>``DBI-Error [Tangram]: DBD::mysql::st execute failed: Unknown column 't1.requestdump' in 'field list'''</P>
249 <PRE>
250 ... occours when operating on object-attributes not introduced yet:
251 this should be detected and appended/replaced through:
252 &quot;Schema-Error detected, maybe (just) an inconsistency.
253 Please check if your declaration in schema-module &quot;a&quot; matches structure in database &quot;b&quot; or try to run&quot;
254 db_setup.pl --dbkey=import --action=deploy</PRE>
255 <P>Compare schema (structure diff) with database ...</P>
256 <PRE>
257 ... when issuing &quot;db_setup.pl --dbkey=import --action=deploy&quot;
258 on a database with an already deployed schema, use an additional &quot;--update&quot; then
259 to lift the schema inside the database to the current declared schema.
260 You will have to approve removals and changes on field-level while
261 new objects and new fields are introduced silently without any interaction needed.
262 In future versions there may be additional options to control silent processing of
263 removals and changes.
264 See this CRUD-table applying to the actions occouring on Classes and Class variables when deploying schemas,
265 don't mix this up with CRUD-actions on Objects, these are already handled by (e.g.) Tangram itself.
266 Classes:
267 C create -&gt; yes, handled automatically
268 R retrieve -&gt; no, not subject of this aspect since it is about deployment only
269 U update -&gt; yes, automatically for Class meta-attributes, yes/no for Class variables (look at the rules down here)
270 D delete -&gt; yes, just by user-interaction
271 Class variables:
272 C create -&gt; yes, handled automatically
273 R retrieve -&gt; no, not subject of this aspect since it is about deployment only
274 U update -&gt; yes, just by user-interaction; maybe automatically if it can be determined that data wouldn't be lost
275 D delete -&gt; yes, just by user-interaction
276 </PRE>
277 <PRE>
278
279 It's all about not to be able to loose data simply while this is in pre-alpha stage.
280 And loosing data by being able to modify and redeploy schemas easily is definitely quite easy.</PRE>
281 <PRE>
282
283 As we can see, creations of Classes and new Class variables is handled
284 automatically and this is believed to be the most common case under normal circumstances.</PRE>
285 <P>
286 <H2><A NAME="features">FEATURES</A></H2>
287 <PRE>
288 - Get this stuff together with UML (Unified Modeling Language) and/or standards from ODMG.
289 - Make it possible to load/save schemas in XMI (XML Metadata Interchange),
290 which seems to be most commonly used today, perhaps handle objects with OIFML.
291 Integrate/bundle this with a web-/html-based UML modeling tool or
292 some other interesting stuff like the &quot;Co-operative UML Editor&quot; from Uni Darmstadt. (web-/java-based)
293 - Enable Round Trip Engineering. Keep code and diagrams in sync. Don't annoy/bother the programmers.
294 - Add support for some more handlers/locators to be able to
295 access the following standards/protocols/interfaces/programs/apis transparently:
296 + DBD::CSV (via Data::Storage::Handler::DBI)
297 (-) Text::CSV, XML::CSV, XML::Excel
298 - MAPI
299 - LDAP
300 - DAV (look at PerlDAV: <A HREF="http://www.webdav.org/perldav/">http://www.webdav.org/perldav/</A>)
301 - Mbox (use formail for seperating/splitting entries/nodes)
302 - Cyrus (cyrdeliver - what about cyrretrieve (export)???)
303 - use File::DiffTree, use File::Compare
304 - Hibernate
305 - &quot;Win32::UserAccountDb&quot;
306 - &quot;*nix::UserAccountDb&quot;
307 - .wab - files (Windows Address Book)
308 - .pst - files (Outlook Post Storage?)
309 - XML (e.g. via XML::Simple?)
310 - Move to t3, look at InCASE
311 - some kind of security layer for methods/objects
312 - acls (stored via tangram/ldap?) for functions, methods and objects (entity- &amp; data!?)
313 - where are the hooks needed then?
314 - is Data::Storage &amp; Co. okay, or do we have to touch the innards of DBI and/or Tangram?
315 - an attempt to start could be:
316 - 'sub getACLByObjectId($id, $context)'
317 - 'sub getACLByMethodname($id, $context)'
318 - 'sub getACLByName($id, $context)'
319 ( would require a kinda registry to look up these very names pointing to arbitrary locations (code, data, ...) )
320 - add more hooks and various levels
321 - better integrate introduced 'getObjectByGuid'-mechanism from Data::Storage::Handler::Tangram</PRE>
322 <P>
323 <H3><A NAME="links / references">LINKS / REFERENCES</A></H3>
324 <PRE>
325 Specs:
326 UML 1.3 Spec: <A HREF="http://cgi.omg.org/cgi-bin/doc?ad/99-06-08.pdf">http://cgi.omg.org/cgi-bin/doc?ad/99-06-08.pdf</A>
327 XMI 1.1 Spec: <A HREF="http://cgi.omg.org/cgi-bin/doc?ad/99-10-02.pdf">http://cgi.omg.org/cgi-bin/doc?ad/99-10-02.pdf</A>
328 XMI 2.0 Spec: <A HREF="http://cgi.omg.org/docs/ad/01-06-12.pdf">http://cgi.omg.org/docs/ad/01-06-12.pdf</A>
329 ODMG: <A HREF="http://odmg.org/">http://odmg.org/</A>
330 OIFML: <A HREF="http://odmg.org/library/readingroom/oifml.pdf">http://odmg.org/library/readingroom/oifml.pdf</A></PRE>
331 <PRE>
332 CASE Tools:
333 Rational Rose (commercial): <A HREF="http://www.rational.com/products/rose/">http://www.rational.com/products/rose/</A>
334 Together (commercial): <A HREF="http://www.oi.com/products/controlcenter/index.jsp">http://www.oi.com/products/controlcenter/index.jsp</A>
335 InCASE - Tangram-based Universal Object Editor
336 Sybase PowerDesigner: <A HREF="http://www.sybase.com/powerdesigner">http://www.sybase.com/powerdesigner</A>
337 </PRE>
338 <PRE>
339
340 UML Editors:
341 Fujaba (free, university): <A HREF="http://www.fujaba.de/">http://www.fujaba.de/</A>
342 ArgoUML (free): <A HREF="http://argouml.tigris.org/">http://argouml.tigris.org/</A>
343 Poseidon (commercial): <A HREF="http://www.gentleware.com/products/poseidonDE.php3">http://www.gentleware.com/products/poseidonDE.php3</A>
344 Co-operative UML Editor (research): <A HREF="http://www.darmstadt.gmd.de/concert/activities/internal/umledit.html">http://www.darmstadt.gmd.de/concert/activities/internal/umledit.html</A>
345 Metamill (commercial): <A HREF="http://www.metamill.com/">http://www.metamill.com/</A>
346 Violet (university, research, education): <A HREF="http://www.horstmann.com/violet/">http://www.horstmann.com/violet/</A>
347 PyUt (free): <A HREF="http://pyut.sourceforge.net/">http://pyut.sourceforge.net/</A>
348 (Dia (free): <A HREF="http://www.lysator.liu.se/~alla/dia/">http://www.lysator.liu.se/~alla/dia/</A>)
349 UMLet (free, university): <A HREF="http://www.swt.tuwien.ac.at/umlet/index.html">http://www.swt.tuwien.ac.at/umlet/index.html</A>
350 Voodoo (free): <A HREF="http://voodoo.sourceforge.net/">http://voodoo.sourceforge.net/</A>
351 Umbrello UML Modeller: <A HREF="http://uml.sourceforge.net/">http://uml.sourceforge.net/</A></PRE>
352 <PRE>
353 UML Tools:
354 <A HREF="http://www.objectsbydesign.com/tools/umltools_byPrice.html">http://www.objectsbydesign.com/tools/umltools_byPrice.html</A></PRE>
355 <PRE>
356 Further readings:
357 <A HREF="http://www.google.com/search?q=web+based+uml+editor&amp">http://www.google.com/search?q=web+based+uml+editor&amp</A>;hl=en&amp;lr=&amp;ie=UTF-8&amp;oe=UTF-8&amp;start=10&amp;sa=N
358 <A HREF="http://www.fernuni-hagen.de/DVT/Aktuelles/01FHHeidelberg.pdf">http://www.fernuni-hagen.de/DVT/Aktuelles/01FHHeidelberg.pdf</A>
359 <A HREF="http://www.enhyper.com/src/documentation/">http://www.enhyper.com/src/documentation/</A>
360 <A HREF="http://cis.cs.tu-berlin.de/Dokumente/Diplomarbeiten/2001/skinner.pdf">http://cis.cs.tu-berlin.de/Dokumente/Diplomarbeiten/2001/skinner.pdf</A>
361 <A HREF="http://citeseer.nj.nec.com/vilain00diagrammatic.html">http://citeseer.nj.nec.com/vilain00diagrammatic.html</A>
362 <A HREF="http://archive.devx.com/uml/articles/Smith01/Smith01-3.asp">http://archive.devx.com/uml/articles/Smith01/Smith01-3.asp</A></PRE>
363
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