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Flask Admin: Format the way relationships are displayed

I would like to change the way the relationships are displayed in the Flask-Admin Index view of a Model. I do have two models connected through a many-to-many relationship which get displayed in the admin index view as well. Unfortunately, the relationships are just separated using a comma, which thus the user might lose the overview quickly. Ideally, I would like to convert the relationships entries into a simple list (e.g. like with li in HTML).
Is there an easy way of achieving this?
Thanks a lot!

Instead of the comma, you can use a <br> tag as the separator.
see column_type_formatters.
Define default formatter and update a list type.
def lineby_list_formatter(view, values):
html = u'<br/> '.join(str(v) for v in values)
return Markup(html)
MY_DEFAULT_FORMATTERS = dict(typefmt.BASE_FORMATTERS)
MY_DEFAULT_FORMATTERS.update({
list: lineby_list_formatter
})
class EventView(ModelView):
...
column_type_formatters = MY_DEFAULT_FORMATTERS

Ok... I figured it out myself: You can manipulate the way the data is rendered with overwriting the function _get_list_value(). see code below
def _get_list_value(self, context, model, name, column_formatters,
column_type_formatters):
"""
Returns the value to be displayed.
:param context:
:py:class:`jinja2.runtime.Context` if available
:param model:
Model instance
:param name:
Field name
:param column_formatters:
column_formatters to be used.
:param column_type_formatters:
column_type_formatters to be used.
"""
column_fmt = column_formatters.get(name)
if column_fmt is not None:
value = column_fmt(self, context, model, name)
else:
value = self._get_field_value(model, name)
choices_map = self._column_choices_map.get(name, {})
if choices_map:
return choices_map.get(value) or value
type_fmt = None
for typeobj, formatter in column_type_formatters.items():
if isinstance(value, typeobj):
type_fmt = formatter
break
if type_fmt is not None:
value = type_fmt(self, value)
### overwritten here
if name == 'items':
html_string = '<ul>'
for item in value.split(','):
html_string += '<li> {} </li>'.format(item)
html_string += '</ul>'
value = Markup(html_string)
return value

Is there a dynamic query builder for Flask using Sqlalchemy?

A simple query looks like this
User.query.filter(User.name == 'admin')
In my code, I need to check the parameters that are being passed and then filter the results from the database based on the parameter.
For example, if the User table contains columns like username, location and email, the request parameter can contain either one of them or can have combination of columns. Instead of checking each parameter as shown below and chaining the filter, I'd like to create one dynamic query string which can be passed to one filter and can get the results back. I'd like to create a separate function which will evaluate all parameters and will generate a query string. Once the query string is generated, I can pass that query string object and get the desired result. I want to avoid using RAW SQL query as it defeats the purpose of using ORM.
if location:
User.query.filter(User.name == 'admin', User.location == location)
elif email:
User.query.filter(User.email == email)

You can apply filter to the query repeatedly:
query = User.query
if location:
query = query.filter(User.location == location)
if email:
query = query.filter(User.email == email)
If you only need exact matches, there’s also filter_by:
criteria = {}
# If you already have a dict, there are easier ways to get a subset of its keys
if location: criteria['location'] = location
if email: criteria['email'] = email
query = User.query.filter_by(**criteria)
If you don’t like those for some reason, the best I can offer is this:
from sqlalchemy.sql.expression import and_
def get_query(table, lookups, form_data):
conditions = [
getattr(table, field_name) == form_data[field_name]
for field_name in lookups if form_data[field_name]
]
return table.query.filter(and_(*conditions))
get_query(User, ['location', 'email', ...], form_data)

Late to write an answer but if anyone is looking for the answer then sqlalchemy-json-querybuilder can be useful. It can be installed as -
pip install sqlalchemy-json-querybuilder
e.g.
filter_by = [{
"field_name": "SomeModel.field1",
"field_value": "somevalue",
"operator": "contains"
}]
order_by = ['-SomeModel.field2']
results = Search(session, "pkg.models", (SomeModel,), filter_by=filter_by,order_by=order_by, page=1, per_page=5).results

https://github.com/kolypto/py-mongosql/
MongoSQL is a query builder that uses JSON as the input.
Capable of:
Choosing which columns to load
Loading relationships
Filtering using complex conditions
Ordering
Pagination
Example:
{
project: ['id', 'name'], // Only fetch these columns
sort: ['age+'], // Sort by age, ascending
filter: {
// Filter condition
sex: 'female', // Girls
age: { $gte: 18 }, // Age >= 18
},
join: ['user_profile'], // Load the 'user_profile' relationship
limit: 100, // Display 100 per page
skip: 10, // Skip first 10 rows
}

How to set group = true in couchdb

I am trying to use map/reduce to find the duplication of the data in couchDB
the map function is like this:
function(doc) {
if(doc.coordinates) {
emit({
twitter_id: doc.id_str,
text: doc.text,
coordinates: doc.coordinates
},1)};
}
}
and the reduce function is:
function(keys,values,rereduce){return sum(values)}
I want to find the sum of the data in the same key, but it just add everything together and I get the result:
<Row key=None, value=1035>
Is that a problem of group? How can I set it to true?

Assuming you're using the couchdb package from pypi, you'll need to pass a dictionary with all of the options you require to the view.
for example:
import couchdb
# the design doc and view name of the view you want to use
ddoc = "my_design_document"
view_name = "my_view"
#your server
server = couchdb.server("http://localhost:5984")
db = server["aCouchDatabase"]
#naming convention when passing a ddoc and view to the view method
view_string = ddoc +"/" + view_name
#query options
view_options = {"reduce": True,
"group" : True,
"group_level" : 2}
#call the view
results = db.view(view_string, view_options)
for row in results:
#do something
pass

Return JSON object to View with Flask and Ajax

I am trying to return a python dictionary to the view with AJAX and reading from a JSON file, but so far I am only returning [object Object],[object Object]...
and if I inspect the network traffic, I can indeed see the correct data.
So here is how my code looks like. I have a class and a method which based on the selected ID (request argument method), will print specific data. Its getting the data from a python discretionary. the problem is not here, have already just tested it. But just in case I will link it.
# method to create the directionary - just in case #
def getCourselist_byClass(self, classid):
"""
Getting the courselist by the class id, joining the two tables.
Will only get data if both of them exist in their main tables.
Returning as a list.
"""
connection = db.session.connection()
querylist = []
raw_sql = text("""
SELECT
course.course_id,
course.course_name
FROM
course
WHERE
EXISTS(
SELECT 1
FROM
class_course_identifier
WHERE
course.course_id = class_course_identifier.course_id
AND EXISTS(
SELECT 1
FROM
class
WHERE
class_course_identifier.class_id = class.class_id
AND class.class_id = :classid
)
)""")
query = connection.engine.execute(raw_sql, {'classid': classid})
for column in query:
dict = {
'course_id' : column['course_id'],
'course_name' : column['course_name']
}
querylist.append(dict)
return querylist
my jsonify route method
#main.route('/task/create_test')
def get_courselist():
#objects
course = CourseClass()
class_id = request.args.get('a', type=int)
#methods
results = course.getCourselist_byClass(class_id)
return jsonify(result=results)
HTML
and here is how the input field and where it should link the data looks like.
<input type="text" size="5" name="a">
<span id="result">?</span>
<p>click me
and then I am calling it like this
<script type=text/javascript>
$(function() {
$('a#link').bind('click', function() {
$.getJSON("{{ url_for('main.get_courselist') }}", {
a: $('input[name="a"]').val()
}, function(data) {
$("#result").text(data.result);
});
return false;
});
});
</script>
but every time I enter a id number in the field, i am getting the correct data. but it is not formatted correctly. It is instead printing it like [object Object]
source, followed this guide as inspiration: flask ajax example

The data return by your server is like: {result: [{course_id: 'xxx', course_name: 'xxx'}]}, in which data.result is a JS Array.
when you set it to $("#result").text(), JS convert a array to string, so the result is [object Object].
You should iterate over the array to construct a string, then set the string in DOM, like:
courseStr = data.result.map(function(course) {return course.course_id + '-' + course.course_name; }).join(',');
$("#result").text(courseStr);

The API description for flask.json.jsonify indicates it's expecting keyword parameters. What you actually want to do seems to be serialize a list object containing dictionaries, have you tried flask.json.dumps instead? Assuming you've got the dumps symbol imported, instead of your jsonify call you can try:
return dumps(results)

Django get url regex by name

I have a case where I have defined some Django url patterns and now I want to retrieve the regular expression associated with a given pattern. I want that because I want to pass these regular expressions to the client so I can check urls in client as well ( I'm talking about browser side history manipulation ) and fire appropriate handlers ( in JavaScript ) when there is a match.
For example if I have:
# urls.py
urlpatterns = patterns("",
url(r"^$", Index.as_view(), name="index"),
url(r"^user/", include("User.urls", namespace="User")),
)
# User/urls.py
urlpatterns = patterns("",
url(r"^profile/(?P<slug>.*)$", GetProfile.as_view(), name="get_profile")
)
then I need the following function:
>>> get_regex("User:get_profile")
'^user/profile/(?P<slug>.*)$'
( or however Django translates it ). Note that I'm using namespaces. Any ideas? Django1.5.
Also I've managed to write a function that returns the urlpattern object associated with a passed name, however doing url.regex.pattern returns '^profile/(?P<slug>.*)$. So as you can see there is no leading ^user/.

There are several javascript reverse implementations out there.
http://djangojs.readthedocs.org/en/latest/djangojs.html#reverse-urls
https://github.com/version2/django-js-reverse
It's not the regex, but you could test the urls in your client code just like you do in the server, so it's even better in my opinion.
EDIT: Since you need to ignore URL arguments, you could get an idea from the source of django-js here. It already removes optional URL arguments, so it's probably very similar to what you describe.
The code iterates over every pattern removing the ?P from each argument subregex so you could just replace them with .*.
The point is you have in that source every regex you could possibly need to do your implementation. See the global patterns in lines 24-29.

So I've tried few things and finally I came up with my own solution. First I convert urlpatterns into a form which JavaScript understands:
import re
converter = re.compile(r"\?P<.*?>")
def recursive_parse(urlpatterns, lst):
for pattern in urlpatterns:
obj = {
"pattern": converter.sub("", pattern.regex.pattern)
}
if hasattr(pattern, "name") and pattern.name is not None:
obj["name"] = pattern.name
if hasattr(pattern, "namespace"):
obj["namespace"] = pattern.namespace
if hasattr(pattern, "url_patterns"):
if "urls" not in obj:
obj["urls"] = []
recursive_parse(pattern.url_patterns, obj["urls"])
lst.append(obj)
def generate_paths(urlpatterns):
paths = []
recursive_parse(urlpatterns, paths)
return paths
Then I call generate_paths(urlpatterns), JSON-stringify the result and pass it to JavaScript (note that in JavaScript I have to convert regular expressions as strings to RegExp objects). In JavaScript I have
var recursive_check = function(url, patterns, names, args) {
var l = patterns.length;
for (var i = 0; i < l; i++) {
var pat = patterns[i],
match = pat.pattern.exec(url);
pat.lastIndex = 0;
if (match) {
names.push(pat.namespace || pat.name);
var f = match.shift(),
url = url.replace(f, ""),
ml = match.length;
for (var j = 0; j < ml; j++) {
args.push(match[j]);
}
if (pat.urls) {
recursive_check(url, pat.urls, names, args);
}
break;
}
}
};
var fire_handler = function(url) {
var names = [], args = [];
recursive_check(url, patterns, names, args);
// do something...
};
Now in // do something... I can do something with names and args. For example I can keep a dictionary of named handlers, I can search for a handler (based on names) and call it with args.
That's the solution that works for me. Converting urlpatterns to JavaScript patterns might not be perfect (since converter seems to be a bit too simplified) but it works in most simple cases.

Try this:
from django.core.urlresolvers import get_resolver
resolver = get_resolver(None)
url = resolver.reversed_dict.getlist('get_profile')
if url:
pattern = url[0][1]

Not an answer but might be useful to someone else looking at this.
The following generates a list of all, complete url patterns in the Django project, including for nested URLRegexResolvers, based on #Freakish's code.
import re
from django.core.urlresolvers import get_resolver
converter = re.compile(r"\?P<.*?>")
def trim_leading_caret(s):
return s[1:] if s.startswith('^') else s
def recursive_parse(urlpatterns, lst, prefix=None):
for pattern in urlpatterns:
path = (prefix or '') + trim_leading_caret(converter.sub("", pattern.regex.pattern))
if hasattr(pattern, "url_patterns"):
recursive_parse(pattern.url_patterns, lst, path)
else:
lst.append('^' + path)
def generate_paths(urlpatterns):
paths = []
recursive_parse(urlpatterns, paths)
return paths
generate_paths(get_resolver(None))

As far as I understood, you want to be able to return the regex expression (and not the url) of a given view.
This is my sketch of solution:
The function url returns an instance of RegexURLResolver. This class does store the regex, because it calls LocaleRegexProvider on __init__ (in this line and this line).
So, I think that you can
reverse search the view plus namespace
get the tuple of that view from the tuple of tuples urlpatterns
return _regex of the first argument, LocaleRegexProvider._regex (or regex()), of the tuple respective to the view.
I'm not sure this works (didn't tested), neither that it is the best solution, but at least you have some links on where Django stores the regex.