From LAMP to DARC
October 19, 2005 § Leave a comment
You’ve heard of LAMP?
Meet
its 21st-century cousin: DARC
? Darwin
? Apache
? Rails
?
CoreData
CoreData
This is especially cool when
combined with microformats. Click [Read more] for a very rough
demo script. You can also download the DARCdemo source code.
On Mac OS X
10.4:
10.4:
A.
Setup
1. Install Xcode Developer Tools
2. Install Ruby on Rails.
1. In Xcode, create a new Core Data Document-based Cocoa project,
“DARCedit”
“DARCedit”
5. Optionally, create a many-to-many relationship
between them
between them
6. Open MyDocument.nib, and add a Tab view with
“Users” and “Events” panes
“Users” and “Events” panes
7. Select, then option-drag each entity from the
model view into its respective tab pane
model view into its respective tab pane
8. Build. run, and
test
test
C. Create
Project
1. From an appropriate
directory, type:
a. $ rails DARCdemo
b. $ cd
DARCdemo
DARCdemo
2. From
DARCedit.app:
a. Populate a few database entries in each
table
table
b. Save as “DARCdemo/db/darc.sql” (an SQLite3
database)
database)
3. Edit config/database.yml
(e.g., using TextMate)
? development:?ÊÊadapter:
sqlite3?ÊÊdbfile: db/darc.sql
sqlite3?ÊÊdbfile: db/darc.sql
? Trim other fields
? Note: “dbfile” not
“database”
“database”
4. Here’s where you’d edit
Apache to setup a fastcgi connection, but we’ll ignore that for
now.
D. Create
Objects
1. Create model objects
(note initial Capital)
a. $ ./script/generate model User
b. $ ./script/generate model Event
c.
2. Map to
CoreData’s weird naming scheme. In
app/models/{event,user}.rb,
add:
2. Map to
CoreData’s weird naming scheme. In
app/models/{event,user}.rb,
add:
a. set_table_name “ZEVENTS” # or
ZUSERS
ZUSERS
b. set_primary_key
“Z_PK”
“Z_PK”
3. Generate scaffold
code
a. $ ./script/generate scaffold
User
User
b. $ ./script/generate scaffold Event # can
overwrite stylesheet (‘Y’)
overwrite stylesheet (‘Y’)
c. Note: does
not
generate Edit/New scaffolds, due to unconventional primary key (fixed in
download)
not
generate Edit/New scaffolds, due to unconventional primary key (fixed in
download)
4. Run project
a. $ (./script/server&)
&&
&&
b. > sleep 10 &&
c. > open -a FireFox
http://localhost:3000/users
http://localhost:3000/users
d. Click “show” to see detailed list
view
view
e. $ killall
ruby to stop (often not needed; just refresh
to pick up changes)
ruby to stop (often not needed; just refresh
to pick up changes)
f. WARNING: “Edit” and “New” don’t work (by
default) and will corrupt the
database
default) and will corrupt the
database
E. Add
Microformats
1. Patch
ActiveRecord to restore original column names
a. Add “require ‘active_record_patch’ ” to
config/environment.rb
config/environment.rb
b. Create file “config/active_record_patch.rb”
containing:
containing:
? class
ActiveRecord::ConnectionAdapters::Column
ActiveRecord::ConnectionAdapters::Column
? def css_name
? human_name[1..-1].gsub(/
/,’-‘)
/,’-‘)
? end
?
end
end
2. Edit
app/views/users/list.rhtml
?
Change: <% for user in @users
%>\n<tr >
Change: <% for user in @users
%>\n<tr >
? ->
To: <% for user in @users %>\n<tr
class=”vcard”>
To: <% for user in @users %>\n<tr
class=”vcard”>
?
Change: <td><%=h
user.send(column.name)
%></td>
Change: <td><%=h
user.send(column.name)
%></td>
? ->
To:
<td class=”<%= column.css_name
%>”><%=h
user.send(column.name)
%></td>
To:
<td class=”<%= column.css_name
%>”><%=h
user.send(column.name)
%></td>
? Repeat for
app/views/events/list.rhtml
using
“class=vevent”
app/views/events/list.rhtml
using
“class=vevent”
3.
Edit
app/views/users/show.rhtml
? Wrap the for loop in: <dl class=”xoxo
vcard“>
# ‘vevent’ for events
vcard“>
# ‘vevent’ for events
? Replace the <p> with <dt> and
a <dd> containing the class:
a <dd> containing the class:
? <dt><%= column.human_name
%>:</dt>
%>:</dt>
? <dd class=”<%= column.human_name
%>”><%=h
@user.send(column.name)
%></dd>
%>”><%=h
@user.send(column.name)
%></dd>
? Repeat for
app/views/events/list.rhtml
using
@event
and
“class=vevent”
app/views/events/list.rhtml
using
@event
and
“class=vevent”
4.
Display in Firefox (if GreaseMonkey installed)
a. $ open -a FireFox
http://localhost:3000/users
http://localhost:3000/users
b. Click on the “>>>hcard”
graphic
graphic
c. Select “show vcard as text”
d. Go back then click “Show” link
e. Click on this “>>>hcard”
graphic
graphic
f. Now select “home” under “Show in Google
Maps”
Maps”
g. Go back and repeat using “Add to Address
Book”
Book”
? Extract and save xoxo.py from microformats.org
? To see the internal data structures,
uncomment this line (near the end): #print
>>sys.stderr, structs
uncomment this line (near the end): #print
>>sys.stderr, structs
? $ python xoxo.py
http://localhost:3000/users/show/1 > test.html
http://localhost:3000/users/show/1 > test.html
? $ open -e test.html # data was extracted
into Python then re-constituted as HTML
into Python then re-constituted as HTML
? This technique can be used to get
XML-like parsing out of ‘mere’ HTML
XML-like parsing out of ‘mere’ HTML
iHack, therefore iBlog 
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