Using UUID for id on Pages - wagtail

Just getting started with Wagtail. To support interoperability with a legacy system, I'd like to have the id/pk of my Page objects be UUIDs instead of Integers. I tried just adding a id = models.UUIDField(primary_key=True, editable=False, default=uuid.uuid4) to my class that inherits from Page but I get an error Local field u'id' clashes with field of similar name from base class 'Page'
Is there a simple way to make id be a UUID? Or, do I just need to call it something besides id?

There won't be a simple way to do this, unfortunately - the assumption that IDs are numeric is baked in to the database schema, URL routes, rich text data representation and various other places in Wagtail's design.
Would it be an option to add your UUID column as a new field on your model (named something like legacy_id), and look up on that whenever you need to interoperate with the legacy system - but otherwise leave the primary key as numeric?

Related

Field Type of entity-query not working, correctly retrieves list of content-items but incorrectly stores them as 'Empty Slot"

I have an Authors App which has x amount of authors. I have another app and have configured an Field Input-Type entity-query in it which pulls from the Authors App. It does this correctly and I can select multiple authors. However upon save, when I go to retrieve a content item which should contain the selected authors, I am given "empty slot" for the place of each author
Real entity fields are Entity relations, and they enforce validity. So they only work with entities in the same app, as that's kind of a sealed scope. This is important that Apps can ensure export/import and still work for all standard use cases.
To reference entities of another app you must use strings instead. This can be done using the string-query field which has the same functionality.
The only downside is that your code will need to then look up the entity in the other app using the id or guid (whichever you store) in Razor.

How can the category and product fields in Shopizer be customized, if possible at all?

I am currently using Shopizer as a sort of headless CMS, leveraging its out of the box admin pages and REST API for the content. There is a page for editing products in the admin system but I would like to add and/or remove specific fields. Making changes to the base code seems to be the most obvious solution but it is taking me a significant amount of time to implement it successfully.
Is there some sort of a config file or an initialization process to customize the fields for creating categories and products using Shopizer's admin page? What is the best practice for this scenario if the former approach is not possible?
If you need to add fields the easiest way is to add them in model objects
com.salesmanager.core.model.*
Example of an annotated field
#Column (name ="IP_ADDRESS")
private String ipAddress;
Once you restart your instance the new field will be available.

app engine ndb - how to load entity by key using id?

I am trying to load an entity by key using the id it was assigned by the datastore but I don't see any api method to do this (using NDB). I thought I would be able to make a Key from an integer id and use key.get() to load the entity, but I don't see a way to make a key from just an id. I suspect I am missing something obvious here. How should I load an entity where I only know the id of it?
Another way: ndb.Key(YourModel, id).get().
YourModel.get_by_id() gets a model instance by id.
here the docs:
https://developers.google.com/appengine/docs/python/ndb/modelclass#Model_get_by_id
don't think you can't get an entity by id without knowing the kind because instances of different Model classes can have the same id/key_name
Models in NDB don't define their key type as part of the model. This is nifty in that you can have one given model type that is accessible through multiple different kinds of keys and parents, which makes them more flexible. But it's somewhat problematic because it isn't always clear what the key represents or where it comes from.
So in cases where there's only ever one kind of key for a given model (which is almost every model), I like to create a class method for generating that key, which adds a bit of semantic clarity:
class Book(ndb.Model):
title = ndb.StringProperty()
pages = ndb.IntegerProperty()
#classmethod
def make_key(cls, isbn):
return ndb.Key(cls, isbn)
b = Book.make_key('1234-5678').get()
Sure the added code is not strictly necessary, but it adds clarity and makes my models more long-term maintainable.
You can parse the id to key string:
key = ndb.Key(YourModel, id).urlsafe().
and then:
result = YourModel.query(YourModel.key== key).get().

How to use Yii with a multilingual database model?

I’m having a problem getting the data from my database which I created to be completely multilingual, and I hope someone here can help me.
I’ve split up all my tables in 2 parts; the “universal” table (does not contain any text that needs to be translated) and the table which contains all the fields that need to be translated with their translations.
Example tables:
base_material
id
picture
base_material_i18n
base_material_id
localization_id
name
description
review_status
review_notes
localization
id
language_name
Query to get the translations (using English (en) as a fall-back language if there is no translation available):
SELECT o.id
, o.type
, o.code
, o.position
, ifnull(t.name,d.name) name
, ifnull(t.description,d.description) description
FROM base_material o
INNER JOIN base_material_i18n d
ON ( o.id=d.base_material_id)
LEFT OUTER JOIN base_material_i18n t
ON ( d.base_material_id=t.base_material_id AND t.localization_id='nl' )
WHERE d.localization_id='en'
My question is how I can automatically get those translations (with the fall-back language as in this query) attached to my model in Yii when I’m searching for the base_material objects? (This is only 1 example table, but almost all my tables (20+) are built in this way, so if possible I would be needing something flexible)
An example of an existing system using what I would need is Propel: http://propel.posterous.com/propel-gets-i18n-behavior-and-why-it-matters
Any ideas how to go about doing that? I’ve checked the existing Yii extensions regarding multilingual sites (like Multilingual Active Record), but they all use a different database design (general information+fall-back language in the main table, translations in the i18n table), and I’m not sure how to change those extensions to use my kind of DB model.
If someone knows of a way to change that existing extension so it can use my kind of DB scheme, then that would be absolutely brilliant and probably the best way to do this.
Edit: I've added a bounty because I still can't find anything on how to let Propel work with Yii (there does exist an extension for Doctrine, but Doctrine doesn't support this kind of DB model with translations either), nor any more information as to how to deal with this using an existing Yii extension or with scopes.
Edit: 98 times viewed but only 3 upvotes and 1 comment. I can't help feeling like I'm doing something wrong here, be it in my question or application/database design; either that or my problem is just very unique (which would surprise me, as I don't think my multilingual database design is that absurd ;-). So, if anyone knows of a better all-round solution for multilingual sites with Yii and/or Propel (apart from the current extensions which I really don't like due to the duplication of text fields) or something similar, please let me know as well.
Thanks in advance!
Have you tried http://www.yiiframework.com/extension/i18n-columns/ (based on http://www.yiiframework.com/extension/stranslateablebehavior/)?
It is an alternate, simpler, approach by adding new table fields in the style of {field}_{language code}, and then setting the translated field in the original model to the current language's translation on afterFind.
In essence, it will get you up and running with translatable fields with the translated content being fetched "automatically", for good and bad :). Adding and removing languages (=columns) is done using migrations.
I am also looking for a generic solution to implement i18n into Yii models.
Recently I chose a very similar database schema for a project like you.
The only difference is, that I am not using a separate language table, I store the language information in the i18n table.
The following solution is without a custom SQL statement, but I think this could be implemented with relation params, anyway, if you're working with foreign key in your database (eg. MySQL InnoDB) gii will create relations between your base_material and base_material_i18n table, like
class BaseMaterial extends CActiveRecord
public function relations()
{
return array(
'baseMaterialI18ns' => array(self::HAS_MANY, 'base_material_i18n', 'id'),
);
}
class BaseMaterialI18n extends CActiveRecord
public function relations()
{
return array(
'baseMaterial' => array(self::BELONGS_TO, 'base_material', 'id'),
);
}
Now you'd be able to access your translations by using the object notation for relations.
$model = BaseMaterial::model()->with('baseMaterialI18ns')->findByPk(1);
foreach($model->baseMaterialI18ns AS $translation) {
if ($translation->language != "the language I need") continue:
// do something with translation data ...
}
I thought about creating a behavior or base class for those models which would act a as helper for managing the translations - pseudo code:
I18nActiveRecord extends CActiveRecord
protected $_attributesI18n;
// populate _attributesI18n on query ...
public function __get($name) {
if(isset($this->_attributesI18n['language_I_need'][$name]))
return $this->_attributesI18n[$name];
else if(isset($this->_attributesI18n['fallback_language'][$name]))
return $this->_attributesI18n[$name];
else
parent::__get();
}
CActiveRecord __get() source
There is more work to be done to find the needed i18n record, also you could further limit the with() option to improve performance and reduce parsing on the PHP side.
But there may be different use cases how to determine the value, e.g. all translations, translation or fallback, no fallback (empty value).
Scenarios could be helpful here.
PS: I would be up for a github project!
You can try to use a simple multilingual CRUD extension.
it is very simple to use and modificate. you just need to add language field to your table.
just watch description here: http://all-of.me/yii-multilingual-crud/
it is in alpha state, but tried on a few projects. you can easily modificate it or contact author to fix or add features

DRY unique objects in Django

I want to ensure an object is unique, and to throw an error when a user tries to save it (e.g. via the admin) if not? By unique, I mean that some of the object's attributes might hold the same values as those of other objects, but they can't ALL be identical to another object's values.
If I'm not mistaken, I can do this like so:
class Animal(models.Model):
common_name = models.CharField(max_length=150)
latin_name = models.CharField(max_length=150)
class Meta:
unique_together = ("common_name", "latin_name")
But then each time I refactor the model (e.g. to add a new field, or to change the name of an existing field), I also have to edit the list of fields in the parenthesis assigned to unique_together. With a simple model, that's OK, but with a substantial one, it becomes a real hassle during refactoring.
How can I avoid having to repeat typing out the list of field names in the unique_together parenthesis? Is there some way to pass the list of the model's fields to a variable and to assign that variable to unique_together instead?
Refactoring models is a rather expensive thing to do:
You will need to change all code using your models since field names correspond to object properties
You will have to change your database manually since Django cannot do this for you (at least the version I used the last time when I worked with Django couldn't)
Therefore I think updating the list of unique field names in the model meta class is the least issue you should worry about.
EDIT: If you really want to do this and all of your fields must be "unique together", then the guy at freenode is right and you'll have to write a custom metaclass. This is quite complicated and errorprone, plus it might render your code incompatible to future releases of Django.
Django's ORM "magic" is controlled by the metaclass ModelBase (django.db.models.base.ModelBase) of the generic base class Model. This class is responsible to take your class definition with all fields and Meta information and construct the class you will be using in your code later.
Here is a recipe on how you could achieve your goal:
Subclass ModelBase to use your own metaclass.
Override the method __new__(cls, name, bases, dict)
Inspect dict to gather the Meta member (dict["Meta"]) as well as all field members
Set meta.unique_together based on the names of the fields you gathered.
Call the super implementation (ModelBase.__new__)
Use the custom metaclass for all your unique models using the magic member __metaclass__ = MyMetaclass (or derive an abstract base class extending Model and overriding the metaclass)

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