It seems simple (everything is simple after you’ve seen the solution) but couldn’t find a post so here it goes:
This is a cross-post from SocialCaddy
The problem using Jetty (or Netty or Ring) is that after you start the process, your beloved REPL is “binded” to the server thus forcing you to kill the service, make a change, start the process again, refresh and do it again. Not fun at all. It’s easy to run the process “in the background” and have the REPL available to make changes.
Let’s create a new project (using lein).
> lein new TinyService
Now, we need a project.clj (so we can do a lein deps and have everything installed automagically)
> lein deps
Edit core.clj with this:
You can run the service in REPL by (boot) and then you’ll still have access to REPL. You can change stuff, C+c C+c, refresh and voila! You can even connect to web server (to a JVM to be more exact) and make changes without the need for compilation. And all this from your local emacs!
Enjoy!
I’ve searched around the net for a nice, clean implementation of activerecord in Python but I found none. There are many better libraries for database abstraction out there in Python but I think that Rails’ “activerecord” way is a breeze and a fun way to access a database.
So, my weekend project was to see whether I could hack together a small activerecord for Python.
The first thing I reeeeaally wanted to do, is to create dynamic queries. What dynamic queries are you ask.
Let’s say you have a database and a table with some fruits fields.
Table: People
Fields: id, name, sex
Using ActiveRecord you can do this:
user = People.find_by_name(“Robert”)
and you’ll get all the People with the name Robert. The magic thing is that you haven’t defined anywhere the function find_by_name. Activerecord has only the function find_by and depending on your search it creates automatically a new function called find_by_name (if the ‘name’ field exists on your table). This is all thanks to Ruby’s method_missing function.
Ruby’s method_missing is called automatically from ruby’s VM everytime a function you tried to call was not found. So, when you called find_by_name, ruby couldn’t find the function and after all the search it went to method_missing. From there, activerecord took control and done it’s magic.
That are many different ways to do it in Python but only one comes close to Rails’ implementation.
Behold: __getattr__
Everytime you call a class attribute, this function is called. So, in Python:
user = User.find_by_name(“Robert”)
calls __getatr__ and if the attribute does not exist, it throws an ‘AttributeError’ exception. That’s the place we are going to put our code and create the dynamic queries.
The most difficult part was this: The function __getattr__ gets one parameter (the attribute) so in this example it was the find_by_name. I had to find a way to pass to __getattr__ the query’s argument.
Behold: Lambda
I know a hobby project of mine is awesome when I have to use lambda (old habits from C and Lisp). Using
lambda value: do_smth(value),
you open up the way for another parameter to join the game (hint: value). So, we have this:
dynamic_query = {
“find_by_”: lambda value: self._find(field, value)
}[query]
This is a dictionary emulating a switch/case in Python with lambdas. If you want to add more functions (insert,update) or more logic (find_by_name_and_sex), this is the place to hack.
Check it online at my bitbucket account and push your changes.
I love Nimbuzz (loving it since I first learn about it when I was at the Erlang Factory in London and spoke with a guy from Nimbuzz) ‘cause it was running smoothly on my Symbian and allowing me to connect with Skype. So when I got my HTC Hero, it was the first app I was going to install. But Skype(to Skype) didn’t seem to work (couldn’t speak, couldn’t hear).
I tried Fring where everything seemed to be working smoothly and I noticed that a headphones icon was appering on my notification bar eventhough I had no headphones connected. So, I connected my slick HTC Hero headphones, fired up Nimbuzz and tadaaaa!
Maybe this solves the muted mic for the Droid on Nimbuzz. I hope for an update and video call!
Even though web2py has support for building facebook applications, we didn’t have a way to use Facebook Connect.
I’ve studied many ways (like Facebook’s Javascript API) and checked other frameworks (Rails and Django) and after 4 hours I made a patch to facebook.py that enables web2py (and I’m sure that other python frameworks can use - like webpy) to use Facebook Connect by doing this:
def index():
connected = facebook_connect(request, facebook_settings)
if connected:
user = get_facebook_user(request.facebook)
response.flash = "Hello ", user
return dict(api_key=facebook_settings.FACEBOOK_API_KEY)
Just one line of code and you are done!
You can check a live example here and grub the code from github
Sometimes I want to create a better administration panel for our clients. With this hack you can create an add/edit/delete panel for every table you like and extend it easily. in order to use it you just go inside the controllers and add:
@scaffold(None)
def authors():
pass
this will create an admin page (authors) that has all the properties from the table “authors”. if you have to “admin” a different table just put it’s name:
@scaffold("other_table")
def authors():
pass
Read the comments for more hacks. PS: I have also a new version that you can pass custom queries (I’ll keep you updated). PS2: Also a version with DataTables (http://datatables.net/)
You can also chain decorators in order to prevent unauthorized access:
@auth.requires_login()
@scaffold("other_table")
def authors():
pass
Now, the installation:
First, put this code inside a module (or in a separate file in models).
def scaffold(tblname=None, fieldid=None): “”” Decorator that exposes show/add/edit/delete for admin purposes
You can specify a table name else it will use the
name of the function as table name
You can specify a field id that will be displayed for the record
else it will use the first field value
"""
def decorator_outside(func):
def decorator_inside(*args):
db_name = db # we could get the database name from globals
table_name = func.__name__ if tbl_name == None else tbl_name
if table_name not in db_name.tables:
raise Exception("No table with name '%s' found" % table_name)
form = None
if len(request.args) > 1:
action = request.args[0]
record_id = request.args[1]
if action == 'create':
form = crud.create(db_name[table_name])
elif action == 'show':
form = crud.read(db_name[table_name], record_id)
elif action == 'edit':
form = crud.update(db_name[table_name], record_id)
elif request.args[0] == 'delete':
form = crud.delete(db_name[table_name], record_id)
result = db_name(db_name[table_name].id > 0).select()
func()
return dict(rows=result, cntr_name=table_name, form=form, field_id=field_id)
return decorator_inside
return decorator_outside
The do the action in the controller @scaffold(“other_table”) def authors(): pass
Finally create a view file:
{{extend 'layout.html'}}
{{ include 'scaffold.html' }}
and paste this into your views folder:
{{= form if form != None else "" }}
<br />
<table>
{{ i = 0 }}
{{ for row in rows: }}
{{ i += 1 }}
<tr class="{{='even' if i%2 else 'odd'}}">
<td class='main'><a href="{{= URL(r=request, f=cntr_name+'/show',
args=row.id) }}">{{= row.values()[field_id] }}</a></td>
<td><a href="{{= URL(r=request, f=cntr_name+'/edit',
args=row.id) }}">Edit</a></td>
<td><a href="{{= URL(r=request, f=cntr_name+'/delete',
args=row.id) }}">Delete</a></td>
</tr>
{{ pass }}
</table>
{{ if not len(rows): }}
No records found
{{ pass }}
<br />
<a href="{{= URL(r=request, f=cntr_name+'/create/new') }}">Add new</a>
This is the second part of integrating CKEditor in web2py. I should warn you that quotes are messed up in the blog so you can check at web2pyslices for the updated (and ready for copy-paste) version.
What it needs to be done in order to have ckeditor uploading works. First, it needs a “file browser” url. That’s just a form with an upload field where we can use to find and upload files. The think is that we must return the path of the uploaded file BACK to the parent form. The most difficult part is activating the Upload button. That is done by specifying the “filebrowserBrowseUrl”. So, here it goes!
Let’s add a new table that will hold our files:
import datetime;
timestamp = datetime.datetime.today()
db.define_table('files',
Field('title', 'string'),
Field('uploaded_data', 'upload'),
Field('created_on','datetime',default=timestamp))
db.files.title.requires = IS_NOT_EMPTY()
db.files.uploaded_data.requires = IS_NOT_EMPTY()
Now, lets add an action the our controller
def upload_file():
url = ""
form = SQLFORM(db.files, showid=False)
if form.accepts(request.vars, session):
response.flash = T('File uploaded successfully!')
url = URL(r=request, f="download",
args = db(db.files.title == request.vars.title).select(orderby=~db.files.created_on)[0].uploaded_data)
return dict(form=form, cknum=request.vars.CKEditorFuncNum, url=url)
and a view upload_file.html:
{{extend 'layout.html'}}
<h2>Upload file</h2>
{{=form}}
{{ if url != "": }}
<script type="text/javascript">
window.opener.CKEDITOR.tools.callFunction({{=cknum}}, '{{=url}}');
</script>
{{ pass }}
Then, lets add the javascript files to our layout AFTER web2py_ajax.html:
<script type="text/javascript" src="{{=URL(request.application,'static','js/ckeditor/ckeditor.js')}}"></script>
Finally, lets create a test page:
{{extend 'layout.html'}}
{{=form}}
<script type="text/javascript">
var ckeditor = CKEDITOR.replace('page_body', {
filebrowserBrowseUrl : "{{=URL(request.application, c='default', f='upload_file')}}",
//filebrowserUploadUrl : "{{=URL(request.application, c='default', f='upload_file')}}",
});
</script>
We are ready!
Optimizing this blog post, which shows you how to create a greek to greeklish “translator”, I’ve created a permalink function that creates urls from greek titles (but you can use your language).
Enjoy!
def create_permalink(s):
“”“
Create greeklish permalinks.
Also works for english.
“”“
import string
import re
input_string = s.lower().decode(‘utf-8’).encode(‘iso-8859-7’, ‘replace’)
from_chars = ‘αβγδεζηθικλμνξοπρσςτυφχψωάήέίόύώϊ’.decode(‘utf-8’).encode(‘iso-8859-7’, ‘replace’)
to_chars = ‘abgdezh8iklmn3oprsstufxywaheiouwi’
translation_table = string.maketrans(from_chars, to_chars)
input_string = string.translate(input_string, translation_table)
return re.compile(“\W+”, re.UNICODE).sub(“_”, input_string)
Although web2py comes with an integrated editor, I really like ckeditor and using it for a text field is trivial using widgets!
First, install ckeditor (put the ckeditor inside a js/ckeditor file in your static folder and include it) :
<script type=”text/javascript” src=”{{=URL(request.application,’static’,’js/ckeditor/ckeditor.js’)}}”></script>
After that, we define a ‘body’ text field (or whatever name you like):
db.define_table(‘page’,
# more Fields …
Field(‘body’, ‘text’))
Then, inside your db.py (or to another file in your models directory) put the widget:
def advanced_editor(field, value):
return TEXTAREA(_id = str(field).replace(‘.’,’_’), _name=field.name, _class=’text ckeditor’, value=value, _cols=80, _rows=10)
and use the widget
db.page.body.widget = advanced_editor
From now, SQLFORM will use ckeditor to show/edit/save data!
