Add model into an existing model RDF - merge

I tried to merge 2 existing RDF/XML models. I tried different solutions:
model1.union(model2)
model1.add(model2) //adding a complete model
model1.add(model2.listStatements())
I'm using Jena in Java.
I removed enveloping tags (like Equipment) from the second model, but I always have the same problem: the resulting model is not really merged: it contains an envelopment for each added model. E.g., I have 2 documents, but different endpoints. They should be merged to have one document which contains all data:
bookid123 in endpointA
<rdf:RDF
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:si="http://www.w3schools.com/rdf/">
<rdf:Description rdf:about="http://endpointA/bookid123">
<si:title>W3Schools.com</si:title>
</rdf:Description>
</rdf:RDF>
bookid123 in endpointB
<rdf:RDF
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:si="http://www.w3schools.com/rdf/">
<rdf:Description rdf:about="http://endpointB/bookid123">
<si:author>Jan Egil Refsnes</si:author>
</rdf:Description>
</rdf:RDF>
As result, I something like this:
<rdf:RDF
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:si="http://www.w3schools.com/rdf/">
<rdf:Description rdf:about="http://endpointA/bookid123">
<si:title>W3Schools.com</si:title>
</rdf:Description>
<rdf:Description rdf:about="http://endpointB/bookid123">
<si:author>Jan Egil Refsnes</si:author>
</rdf:Description>
</rdf:RDF>
but I need something like this:
<rdf:RDF
xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:si="http://www.w3schools.com/rdf/">
<rdf:Description rdf:about="http://couldbeanything/bookid123">
<si:title>W3Schools.com</si:title>
<si:author>Jan Egil Refsnes</si:author>
</rdf:Description>
</rdf:RDF>
Is there a smarter way than getting every statement of model1, adding them to model2, except statements which are different because of the source-uri?

In RDF, the identifiers are complete URI's and they are not considered part of any document you happen to find them in. So in your example,
http://endpointA/bookid123
http://endpointB/bookid123
are unique and independent names for things. So it is quite correct from an RDF perspective that merge will not combine triples with those subjects together.
In your case, you are wanting to assert that, by some means outside of the RDF model, you know that http://endpointA/bookid123 and http://endpointB/bookid123 are actually the same resource and that therefore statements about one can be considered to be also statements about the other.
There are two ways to handle this. Firstly, you could use OWL to express that the two resources denote the same individual (I'll use Turtle syntax for brevity, it doesn't change the meaning):
<http://endpointA/bookid123> owl:sameAs <http://endpointB/bookid123> .
In order for this to work, you'll need to use a model with an OWL reasoner (such as OWL_MEM_MICRO_RULE_INF) attached.
The second way is more brute force: for each two resources resource1 and resource2 that you want to merge, run a loop to copy the statements of one to also be statement of the other:
for (StmtIterator i = resource1.listStatements(); i.hasNext(); ) {
Statement s = i.next();
resource2.addProperty( s.getPredicate(), s.getObject() );
}

Related

How to copy/clone DbContextOptions<AContext> to a DbContextOptions<BContext>?

Setting:
One db with many tables, grouped by modules. The moduleTableGroups are independent, there are no relationships in between.
Design:
1: The modules have each there own Context, to keep them small and clear.
2: Because it is an very old Database with manual administration of PKeys and sequences it must be possible to nest SaveChanges, when handling those things in the context.
E.G. AContext has a table with an entity which has a ValueGenerator which reads an incremented value from a table. Because it should be finished before AContext.SaveChanges(), is called, it must be done in an seperate SeqContext in the same db which can handle the concurency issues which might occur.
The SeqContext depends on the DbOptionsContext of AContext.
Wishes:
1: Instead of create Options for each Context which is currently needed, becaus a context seems only to accept context specific options, I'd like to either use the same DbContextOptions for many context or copy or cast the options to a new .
DbContextOptions<AContext> aContextOptions = new DbContextOptionsBuilder<AContext>(). . .Options;
// casting:
DbContextOptions<BContext> bContextOptions = (DbContextOptions<BContext>) aContextOptions;
// copy construction:
DbContextOptions<BContext> bContextOptions = new DbContextOptionsBuilder<BContext>(aContextOption).Options;
2: Because of the dependency of SeqContext to AContext especially in testing scenarios it would be useful to do something from within a AContext like:
SeqContext = new SeqContext((DbContextOptions<SeqContext>) this.getOptions());
You might get the idea. How can I archive to share options between different TContext right now?

v2.ODataModel: which API is more preferred? "bindElement" or "read"?

I set the view.setModel(model), get the model for the view, and request for model.read("/entitySet('10000')").
The model is then filled up with /entitySet('10000')/properties.
But it is difficult to assign them to view fields, as now in the view, <Text text="{property}"> doesn't work. It has to be <Text text="{/entitySet('10000')/property}">.
On the other hand, if I set view's context binding to "/entitySet('10000')", then <Text text="{property}"> would start working.
Which one is the preferred method? When to use .read?
I almost never use .read if I want to use the results from an OData call directly in a binding context. The only time I use .read is if I want to manipulate the results before doing anything with them.
Look at this example from the sdk for instance: https://ui5.sap.com/#/entity/sap.ui.table.Table/sample/sap.ui.table.sample.OData
Syntax on this kind of binding is similar to read but with a few differences in events, and a few different types of methods depending on what you want to bind. Binding to a view for instance uses bindElement:
this.getView().bindElement("/entitySet('1000')");
After this, fields on that particular entity can be accessed as <Text text="{property}" />.
Here's an example from one of my current apps with events and some other call parameters:
this.getView().bindElement({
path: `/Orders('${currentOrderNumber}')`,
parameters: {
expand: 'Texts'
},
events: {
dataRequested: _ => this.getView().setBusy(true),
dataReceived: data => {
if (!this.getView().getBindingContext()) {
// navigate to `Not Found` view
}
},
change: _ => this.getView().setBusy(false)
}
});
For a table, it's slightly different, since it depends on the aggregation you wish to bind, such as
oTable.bindRows({
path: "properties"
});
Which is the same as:
<Table rows="{properties}" />
It's always important to be more expressive. Use the API that is specifically designed to do that one task.
Comparing the two variants:
myModel.read(sPath) with text="{/path/property}"
myControl.bindElement(sPath) with text="{property}"
I'd be perplexed about the 1st call whereas in the 2nd call, I'd know exactly what you want to achieve (You want to bind element. Alternatively, bindObject can be also used).
The same applies to the framework. Since you're telling exactly what you want to achieve, the framework can improve its behavior based on your intent. E.g.: in (route)PatternMatched handler when the user navigates to the same page, .bindElement with the same path won't trigger another request since the model already stored the entity from the previous call. It can show the result immediately.
With .read, however, the framework doesn't know what you want to achieve, so it sends the request right away regardless of the application state.
Additionally, the 1st variant is anything but future-proof. It relies on the cached results. It's almost a side-effect that it works at all. The problem is that there is no guarantee that this behavior will continue to work in later versions. Also there won't be read method in V4 ODataModel.
TL;DR
v2.ODataModel#read
Does not create context from the response. Repeating .read("<same path>") always sends a new request.
Less expressive. Encourages app developers to work with a client-side model (e.g. JSONModel).
Application loses context awareness, increasing TCO, less future-proof.
bindElement or bindObject
Creates context from the response and stores it internally so that the same request can return the data immediately.
Clearly expresses the intent; application as well as framework can work with the existing APIs.
More future-proof: v4.ODataModel does not support manual read. Imagine you've built your applications with the v2ODataModel.read-jsonModel.setData approach, and you need to migrate to v4. Have fun. :)
I honestly think that v2.ODataModel#read should have never become a public method. I wouldn't encourage anyone to use .read except of when reading the $count value manually.
If the entity values need to be formatted, there are formatters and binding types out of the box which are also easy to extend.
If the application needs to restructure the response body, usually it's a sign of a poor design of the data model or the service not conforming to the OData spec.
I almost agree with Jorg, but not entirely:
It really depends on what are you trying to achieve. If looking to display data from backend then the easiest way to go is with this.getView().bindElement()
but if you are in need to manipulate data before displaying (like formatting text, displaying images from base64 strings, etc) OR if you would like to create new entity using some of existing data, OR update the existing data - the this.getModel(sName).read() is the way to go - as you can set read entity with all its deep entities to JSONModel in successCallback and manipulate it from the localModel.
If using localModel the dataBinding is pretty much the same in the view - except you have to additionally give model name to take data from. So for example, if in successCallback of your Model.read() you set your data to Model named "localModel":
this.getModel().read(sObjectPath, {
urlParameters: {
$expand: ""
},
success: function (oData) {
// "localModel" is name you gave in onInit function to your new JSONMOdel, when setting it to View e.g. this.getView().setModel(oJSONMOdel, "localModel")
this.getModel("localModel").setData(oData);
}
})
then in XML view you would indicate that
<Text text="{localModel>/mainPropertyName}"/>
// for displaying deep entities as List items or in Table
<List items="{localModel>/deepEntityName}">
<StandardListItem title="{localModel>propertyNamefromDeepEntity}" />
</List>
From my experience working with more complex apps that Read-Only - I always use Model.read().

Django Tastypie, Remove Elements From ManyToMany Fields

I am using Tastypie, Django for my project.
To Update a many to many field I have used save_m2m hook.
def save_m2m(self, bundle):
for field_name, field_object in self.fields.items():
if not getattr(field_object, 'is_m2m', False):
continue
if not field_object.attribute:
continue
if field_object.readonly:
continue
related_mngr = getattr(bundle.obj, field_object.attribute)
related_objs = []
print bundle.data[field_name]
for related_bundle in bundle.data[field_name]:
try:
stock = Stock.objects.get(nse_symbol = related_bundle.obj.nse_symbol)
print stock.__dict__
except Stock.DoesNotExist as e:
dataa = {"error_message": e}
raise ImmediateHttpResponse(response=HttpBadRequest(content=json.dumps(dataa), content_type="application/json; charset=UTF-8"))
related_objs.append(stock)
related_mngr.add(*related_objs)
Now I want to remove elements from the same many to many field.
How should I achieve this. Do I have to send a patch request or delete request and how to handle this.
I am begineer in tastypie. I googled it some time and I couldn't find a proper way. Please guide me how to complete this.
Thanks.
I've thought a lot about handing m2m relationships, since most of our app depends on m2m links.
I've settled for the approach of an update method. Pass in the all the references of the relationships you want changed (add and remove), then update the db accordingly. We only pass in the changed values, since if you have a paginated list, you only want to update the items the user has identified. Generally I use a custom hook for this defined in override_urls.
I used to have a separate add and remove method, which worked well until we changed the gui and allowed users simply to change checkboxes. In that approach having an update method was much more useful. You'll have to decide on which method suits your application the best.

Plone 4 - History for second workflow won't show in ##historyview

I have a dexterity content type in Plone 4.2.4. The versioning works fine with the default workflow for this content type, although it is not a workflow shipped with plone, but a custom made.
However, when I enable a second workflow for the same type, everything but the versioning works fine.
additional permissions managed by the second workflow are working
The state changes are working
The difference:
I used different state_variable names for the workflows, which seems to make sense, to have a catalogable field for the state of the second workflow.
I've tried to use the same state variable name, but that didn't help. I have the workflow variable review_history also set in the 2nd workflow and sufficient permissions in the context.
I am (mostly) shure, that I got the permission concept, but I have no clou, how permissions get calculated, when multiple workflows are involved.
Any idea, why the second workflow does not leave a trace in my content types history?
Thanks very much in advance.
Udate
I've reordered the workflows as Ida Ebkes suggested and did see, that all transitions from the 2nd workflow get stored properly. So it seems to be an issue with the historyview.
Since these workflows indeed describe concurrent behaviors of a content type, I really would like to stick with separate workflows and ideally different workflow state variables and catalog indexes.
What I now think needs to be done, is to tweak the historyview.
Here is how I did it. It works for plone 4.2.4 at least.
Since the problem was a display problem, I just had to tweak my historyviewlet. Therefore, I created a folder named viewlets in my product root and created a __init__.py and a configure.zcml file. Then i copied content_history.pt, history_view.pt, review_history.pt and content.py from plone/app/layout/viewlets/ (omelette) to the newly created folder.
The configure.zcml contains two view registrations:
<browser:view
for="*"
name="my-contenthistory"
class=".content.ContentHistoryView"
permission="zope2.View"
/>
<browser:page
for="*"
name="my-historyview"
template="history_view.pt"
permission="zope2.View"
/>
Furthermore, I copied the whole WorkflowHistoryViewlet class from content.py to a different class name. TransferHistory in this case. Then I changed mostly the part that corresponds to the workflow state variable, which was not review_state, but transfer_state. I further found that the initial usage of the 2nd workflow creates also a created entry in the history of the 2nd workflow, that I just filtered .
transfer_history = [x for x in transfer_history if x['action'] != None]
The I corrected the view name in history_view.pt to my new view name.
<div tal:replace="structure here/##my-contenthistory">Content History</div>
Finally, I added my class as parent to the ContentHistoryViewlet class in content.py
class ContentHistoryViewlet(WorkflowHistoryViewlet, TransferHistoryViewlet):
index = ViewPageTemplateFile("content_history.pt")
#memoize
def getUserInfo(self, userid):
[...]
def fullHistory(self):
history = self.workflowHistory() + self.revisionHistory() + self.transferHistory()
if len(history) == 0:
return None
history.sort(key=lambda x: x["time"], reverse=True)
return history
and registered the .zcml in the products configure.zcml
<include package=".viewlets" />
Then I modified content_history.pt and also changed the definition of action_id in the upper part of the file.
[...]
action_id python:item['action'] or item.get('review_state', False) or item.get('transfer_state', False);
[...]
After rebooting the monster and a product reinstall, all state changes from both workflows are shown in the my-historyview.

Zend Framework / Form Element is rendering as a text box rather than a dropdown box

I have the following in a config.ini file: (Zend_Form_Element)
site_status.name = "site_status"
site_status.type = "select"
site_status.label = "Status"
site_status.options.multiOptions.active.key = "Active"
site_status.options.multiOptions.active.value = "Active"
site_status.options.multiOptions.active.key = "Inactive"
site_status.options.multiOptions.active.value = "Inactive"
As you can see this is supposed to be a dropdown (select) box, however it is being rendered as a standard text box. What am I doing wrong?
--> Edit
Rather than tying the elements to a form, I am trying to tie them to a database: In my code it would look something like this:
[{tablename}] // the table name would represent a section in the ini
{column}.name = "{column_name/form_field_id}";
{column}.type = "{form_element_type}"
{column}.label = "{form_element_label}"
...
From there I would pull in the database table(s) that the form would represent data for (one or more tables as necessary). As far as the reasoning for this approach is that (down the road), I want to define (either by ini or some other storage method), a configuration file that would be a list of fields/elements that belong to a specific form (that a non-programmer type could easily edit), that the 'generic' form class would read, pull in the element info, and create the form on the fly.
I do realize however this poses another problem which I haven't yet figured out, and that is how to use table lookups for select elements (without coding the database retrieval of the lookup into the form, so that a non-user could easily just define it without any programming, purely configuration, but that is a whole other topic not part of my question here. (and I think I have viable ideas/solutions to that part of the problem anyhow) -- extra config entries and a generic routine pretty much.
I hope that clarifies my thought process and reason why I am doing it the way I am in the example above.
I have not yet played with using a Zend_Config to construct an instance of Zend_Form.
But a look at the code suggests that Zend_Form::addElement() doesn't directly take a Zend_Config instance as a param. Rather, it looks like you need pass your Zend_Config instance to the form constructor. It also seems that the config format needs to be a little deeper in order to map config keys to setXXX() calls.
In path/to/config/myForm.ini:
[myForm]
myForm.elements.site_status.name = "site_status"
myForm.elements.site_status.type = "select"
myForm.elements.site_status.label = "Status"
myForm.elements.site_status.options.multiOptions.active.key = "Active"
myForm.elements.site_status.options.multiOptions.active.value = "Active"
myForm.elements.site_status.options.multiOptions.inactive.key = "Inactive"
myForm.elements.site_status.options.multiOptions.inactive.value = "Inactive"
Then instantiating:
$formConfig = new Zend_Config_Ini('path/to/config/myForm.ini', 'myForm');
$form = new Zend_Form($formConfig);
Not tested, but looking at this example:
Using Zend_Form with Zend_Config - Andrew Vayanis
it feels like it should go something like the above.
Update
In view of the comments/feedback from #Aaron, two more approaches.
We could extend Zend_Form, implementing a method called something like addElementByConfig in which we would pass the shallow Zend_Config instance that describes the element itself. In fact, we could even just override addElement(), taking a recursive approach: if the first param is an instance of Zend_Config, then call addElement() using the component data.
If the atomicity and re-usability are the primary benefits we seek in using Zend_Config to describe an element, then perhaps we just make a custom element extending Zend_Form_Element. Then we could use these elements in any forms we wish.