Working on a project -flask/sqlalchemy/jinja. If I were to call a join, loop through the set acquire the data through a variable could I call upon that variable multiple layers deep? Example:
orders = Orders.query.join(Products, Orders.id==Products.order_id).all()
Loop through records and find the values:
data = []
for order in orders:
object= {
'id': order.id,
'products': []
}
for product in order.products:
product = {
'name': product.name,
'header':product.header
}
object['products'].append(product)
data.append(object)
Render template passing data as data.
return render_template('something.jinja2', data=data)
In jinja can I do this?:
{% for d in data %}
{{order.products.name}}
{% endfor %}
If I were to do more joins and more loops could I go deeper into relationships?
loop in a loop in jinja
{% for d in data%}
{{ order.id}}
{% for product in d.products %}
{{product.name}}
{% endfor %}
{% endfor%}
Related
i made i dictionary of querysets in one of my views :
list =[]
while(x<100 and i>0):
order_qs_1 = Order.objects.filter(timestamp__range=[start_date, end_date])
x = x+1
i=i-j
list.append(order_qs_1)
context= {
'list':list,
}
but now i don't know how to access the data inside the dictionary in my template
in my template i did something like this :
{% for item in list %}
{{ item }} </br>
{% endfor %}
this is what it renders:
the random numbers and characters are the order_id in my order model
the queryet is a list of orders coming from my order model
but this not what i want , i want the access the data inside each queryset
You can iterate over the querysets. For example:
{% for qs in list %}
<p>
{% for order in qs %}
{{ order }}
{% endfor %}
</p>
{% endfor %}
Here we thus iterate over the querysets qs, and for example render the order. You can thus render individual data of that order, for example {{ order.pk }} for the primary key.
I have line of code in Django template:
<h4>{{ totals.date.weekday }}</h4>
Totals is the Python list, how do i get item of this list by index stored in date.weekday?
This would look in Python like this:
totals[date.weekday]
Creating another variable, which stores date.weekday doesn't work
UPD:
I found a solution:
Just added element of totals list to template context in render
For example:
# ...
return render(request, 'template.html', context={'date_total'=totals[date.weekday()]})
You can access the array directly using
{{ totals.0.date.weekday}} where the 0 is the position that you want.
Also if you want to print all the elements in total you will need a for loop such as:
{% for d in totals %}
{{ d }}
{% endfor %}
about sorting, you can use the pipe order_by but I recommend you to pass the list already ordered from the views
You have to run the "for loop" for this.
{% with counts = 0 %}
{% while counts < totals.count %}
{% if counts == date.weekday %}
<h4>total.counts</h4>
{% endif %}
{% counts += 1 %}
{% endfor %}
I did not get your question completely but i think it might help.
I want to reduce the number of template filter calls in my_filter_function(). Because It's used inside two for-loops inside a template. Please see below for my code setup.
class ModelA(models.model):
models.ForeignKey(OtherModel1)
class ModelB(models.model):
models.ForeignKey(OtherModel2)
class ModelC(models.Model):
a = models.ForeignKey(ModelA)
b = models.ForeignKey(ModelB)
def my_views(request):
return render(request, 'my_template.html', {
'a_list': ModelA.objects.all(),
'b_list': ModelB.objects.all(),
})
and in my template, I have
{% for a in a_list %}
{% for b in b_list %}
{% with b|my_filter_function:a as my_val %}
Val: {{my_val}}
{% endwith %}
{% endfor %}
{% endfor %}
the above template will will call the my_filter_function filter function, I need to find another way to reduce the number of my_filter_function function calls, because the filter function is accessing the DBs several thousand times per template now.
#register.filter
def my_filter_function:(b, a):
z = ModelC.objects.filter(a=a, b=b)
if z.count() > 0:
return "OK"
else:
return "Not OK"
Here's a faster alternative.
Fetch all the ids of A and B in C at once:
z = ModelC.objects.values_list('a_id', 'b_id')
a_related, b_related = zip(*z) # split into a and b ids
Pass these to your context:
def my_views(request):
return render(request, 'my_template.html', {
'a_list': ModelA.objects.all(),
'b_list': ModelB.objects.all(),
'a_related': a_related,
'b_related': b_related,
})
And then use if...in in your template. The custom template filter can now be discarded:
{% for a in a_list %}
{% for b in b_list %}
{% if a.id in a_related and b.id in b_related %}
"OK"
{% else %}
"Not ok"
{% endif %}
{% endfor %}
{% endfor %}
That replaces all the multiple queries in your filter with just one.
Im trying to iterate over a nestled dict list. The first level works fine. But the second level is treated like a string not dict.
In my template I have this:
{% for product in Products %}
<li>
<p>{{ product }}</p>
{% for partType in product.parts %}
<p>{{ partType }}</p>
{% for part in partType %}
<p>{{ part }}</p>
{% endfor %}
{% endfor %}
</li>
{% endfor %}
It's the {{ part }} that just list 1 char at the time based on partType. And it seams that it's treated like a string. I can however via dot notation reach all dict but not with a for loop. The current output looks like this:
Color
C
o
l
o
r
Style
S
.....
The Products object looks like this in the log:
[{'product': <models.Products.Product object at 0x1076ac9d0>, 'parts': {u'Color': {'default': u'Red', 'optional': [u'Red', u'Blue']}, u'Style': {'default': u'Nice', 'optional': [u'Nice']}, u'Size': {'default': u'8', 'optional': [u'8', u'8.5']}}}]
What I trying to do is to pair together a dict/list for a product from a number of different SQL queries.
The web handler looks like this:
typeData = Products.ProductPartTypes.all()
productData = Products.Product.all()
langCode = 'en'
productList = []
for product in productData:
typeDict = {}
productDict = {}
for type in typeData:
typeDict[type.typeId] = { 'default' : '', 'optional' : [] }
productDict['product'] = product
productDict['parts'] = typeDict
defaultPartsData = Products.ProductParts.gql('WHERE __key__ IN :key', key = product.defaultParts)
optionalPartsData = Products.ProductParts.gql('WHERE __key__ IN :key', key = product.optionalParts)
for defaultPart in defaultPartsData:
label = Products.ProductPartLabels.gql('WHERE __key__ IN :key AND partLangCode = :langCode', key = defaultPart.partLabelList, langCode = langCode).get()
productDict['parts'][defaultPart.type.typeId]['default'] = label.partLangLabel
for optionalPart in optionalPartsData:
label = Products.ProductPartLabels.gql('WHERE __key__ IN :key AND partLangCode = :langCode', key = optionalPart.partLabelList, langCode = langCode).get()
productDict['parts'][optionalPart.type.typeId]['optional'].append(label.partLangLabel)
productList.append(productDict)
logging.info(productList)
templateData = { 'Languages' : Settings.Languges.all().order('langCode'), 'ProductPartTypes' : typeData, 'Products' : productList }
I've tried making the dict in a number of different ways. Like first making a list, then a dict, used tulpes anything I could think of.
Any help is welcome!
Bouns: If someone have an other approach to the SQL quires, that is more then welcome. I feel that it kinda stupid to run that amount of quires. What is happening that each product part has a different label base on langCode.
..fredrik
Iterating over a dict yields the keys. You want either the iteritems() or itervalues() method.
{% for partName, partType in product.parts.iteritems %}
<p>{{ partName }}</p>
{% for part in partType %}
<p>{{ part }}</p>
{% endfor %}
....
In my views.py, I'm building a list of two-tuples, where the second item in the tuple is another list, like this:
[ Product_Type_1, [ product_1, product_2 ],
Product_Type_2, [ product_3, product_4 ]]
In plain old Python, I could iteration the list like this:
for product_type, products in list:
print product_type
for product in products:
print product
I can't seem to do the same thing in my Django template:
{% for product_type, products in product_list %}
print product_type
{% for product in products %}
print product
{% endfor %}
{% endfor %}
I get this error from Django:
Caught an exception while rendering: zip argument #2 must support iteration
Of course, there is some HTML markup in the template, not print statements. Is tuple unpacking not supported in the Django template language? Or am I going about this the wrong way? All I am trying to do is display a simple hierarchy of objects - there are several product types, each with several products (in models.py, Product has a foreign key to Product_type, a simple one-to-many relationship).
Obviously, I am quite new to Django, so any input would be appreciated.
Another way is as follows.
If one has a list of tuples say:
mylst = [(a, b, c), (x, y, z), (l, m, n)]
then one can unpack this list in the template file in the following manner.
In my case I had a list of tuples which contained the URL, title, and summary of a document.
{% for item in mylst %}
{{ item.0 }} {{ item.1}} {{ item.2 }}
{% endfor %}
it would be best if you construct your data like {note the '(' and ')' can be exchanged for '[' and ']' repectively, one being for tuples, one for lists}
[ (Product_Type_1, ( product_1, product_2 )),
(Product_Type_2, ( product_3, product_4 )) ]
and have the template do this:
{% for product_type, products in product_type_list %}
{{ product_type }}
{% for product in products %}
{{ product }}
{% endfor %}
{% endfor %}
the way tuples/lists are unpacked in for loops is based on the item returned by the list iterator.
each iteration only one item was returned. the first time around the loop, Product_Type_1, the second your list of products...
You must used this way:
{% for product_type, products in product_list.items %}
{{ product_type }}
{% for product in products %}
{{ product }}
{% endfor %}
{% endfor %}
Don't forget the variable items in the dictionary data
If you have a fixed number in your tuples, you could just use indexing. I needed to mix a dictionary and the values were tuples, so I did this:
In the view:
my_dict = {'parrot': ('dead', 'stone'), 'lumberjack': ('sleep_all_night', 'work_all_day')}
In the template:
<select>
{% for key, tuple in my_dict.items %}
<option value="{{ key }}" important-attr="{{ tuple.0 }}">{{ tuple.1 }}</option>
{% endfor %}
</select>
Just send the template a list of product types and do something like:
{% for product_type in product_type_list %}
{{ product_type }}
{% for product in product_type.products.all %}
{{ product }}
{% endfor %}
{% endfor %}
It's been a little while so I can't remember exactly what the syntax is, let me know if that works. Check the documentation.