API Platform custom IRI with value objects - symfony

I am currently trying to create a custom IRI for one of my entities in API Platform.
I know there is page in the documentation describing how to use a custom IRI (https://api-platform.com/docs/core/identifiers/), but I can't get it working.
My entity uses a value object for the id (currently used for IRI) and also for the name (should be used for IRI). But the values themself are priviate and scalar in the entity.
API Platform seems to get the information what should be used as the identifier, from my XML Doctrine mapping. I already tried to overwrite it by usung annotations, attributues and YAML definitions. Without luck.
The returned error reads:
preg_match(): Argument #2 ($subject) must be of type string
(at this point it receives the value object instead of the actual value)
best regards,
spigandromeda

I solved my problem.
To explain the solution, I have to dig a little into API Platform response generation.
API platform generates an IRI for every entity it returns (colelction and item operation)
it's using the Symfony router go generate the URI
all the necessary information can draw API Platform from different sources (YAML, XML, annotations, attributes)
the information include the identifier(s) defined for the entities resource
API Platform gets the value for the identifier via Symfony property accessor
because the property accessor is using getters before accessing private properties via reflection, it will return the VO
an ordinary VO cannot be used by the Symfony URL generator to create the URL
As I explained, I am using a VO for my Id as well. So I tried to figure out why it was working with the Id VO but not with the name VO.
Simple answer: the Id VO implemented the __toString method and the name VO didn't. So the solution was to let the name VO implement this method as well.
It was interesing to dig into the internal process of API Platform, but I also feel a little stupid :D

Related

oData v4 - ordering outer entity on property in related one-to-many entities

I have an oData model with a couple of one-to-many relationship, say person->addresses and person->driving-licences. I would like to be able to sort the result set based on properties in the address entity and driving licence entity. As there could be more than one address, I would initially select a single item from the addresses set, based on a property called IsPrimary. As there could be more that one driving licence, I would select the 'UK' driving licence. Is this possible?
I was hoping I could do something like:
/people?$expand=addresses($filter=isPrimary eq true),drivinglicences($filter=country eq 'UK')&$orderby=addresses/postcode,drivinglicences/active
Unfortunately I get the following error:
"The query specified in the URI is not valid. The parent value for a property access of a property 'isPrimary' is not a single value. Property access can only be applied to a single value."
Does anyone know if what I'm trying to do is supported by the spec? Or whether it is an issue with my query? Or whether it is an issue with the .NET library.
I'm using:
Microsoft.AspNet.OData - 7.2.3
Many Thanks.
What you see here is by design, or rather not supported by the specification, the error message even highlights the only type of expressions supported:
The query specified in the URI is not valid. The parent value for a property access of a property 'isPrimary' is not a single value. Property access can only be applied to a single value.
So the simplest solution is to modify the API either to include a Function bound to the people collection that applies the $filter or $order directly, or a Function that returns the data in a new shape, one that only has perhaps a singleton PrimaryAddress property. How you include driving license in this result is up to you, it could even be a parameter to the function, perhaps your people controller has a queryable function with this signature:
[EnableQuery]
public IHttpActionResult WithLicences(string countryCode)
However that is out of the scope of OPs question about specific syntax support
Although it seems like an important feature, we must remember that $select (Projection) and $filter are evaluated at different points in time, OData queries follow a similar execution sequence to SQL however the filter criteria and $orderby are evaluated separately, and the projection of the resultset is the last evaluation to be applied.
Due to $filter and $orderby being applied independently, neither concept is even aware of the other and as such neither can reference or assume to be applied before the other.
You can prove this by specifying a field in the $orderby and/or $filter that is not included in the $select, you can even reference singleton navigation fields that are not included in an $expand and the query will evaluate correctly.
The OData spec is similar to a law document, in that to properly understand and apply it we need to understand the original intent of the authors. We can get an initial understanding from the early listing of Addressing Entities
Addressing Entities describes functions that can be bound to collections or entities that return either a single entity or a collection of entities
By allowing special provision of custom functions to be applied the authors are encouraging API designers to provide natural extensions to their resource endpoints that can facilitate the execution of pre-determined queries that may be otherwise complex or problematic to express in pure OData query syntax.
In other words, we are encouraged to customise our APIs to make them easier for the end process to consume, and to guide the consuming developer to make the best use of the API, they shouldn't have to discover everything from first principals.
To achieve OPs type of query in pure SQL would still require either a nested lookup, CTE or self join... advanced syntax. In OData v4, the specification does not provide a syntax for targeting specific items within a collection for path expressions (of which $orderby derives from)
5.1.1.15 Path Expressions
Properties and navigation properties of the entity type of the set of resources that are addressed by the request URL can be used as operands or function parameters, as shown in the preceding examples.
Properties of complex properties can be used via the same syntax as in resource paths, i.e. by specifying the name of a complex property, followed by a forward slash (/) and the name of a property of the complex property, and so on,
Properties and navigation properties of entities related with a target cardinality 0..1 or 1 can be used by specifying the navigation property, followed by a forward slash (/) and the name of a property of the related entity, and so on.
If a complex property is null, or no entity is related (in case of target cardinality 0..1), its value, and the values of its components, are treated as null.
RE: I couldn't find anything explicit in the spec. :)
That is the very thing about the OData specification,the specification does not list what is not supported, only what should be supported. So by omission, if you cannot find a reference to how to do something, then that something is not required to be supported.
Introduction http://docs.oasis-open.org/odata/odata/v4.01/odata-v4.01-part2-url-conventions.html#sec_Introduction ... This specification defines a set of recommended (but not required) rules for constructing URLs to identify the data and metadata exposed by an OData service as well as a set of reserved URL query string operators, which if accepted by an OData service, MUST be implemented as required by this document.
This has been on ongoing discussion held in may threads, recently https://stackoverflow.com/a/55324393/1690217
Many people complain that this is surely a fundamental feature of a data access platform, however it is important to respect the original intent of the OData platform and keep our APIs simple by providing customised endpoints to suit our business domain.

How to have a Symfony API GET call return an embedded json object instead of an IRI

I have been working on a Symfony API with Api Platform and have autogenerated all the endpoints which works fine. Except for one thing, when GETting a entity with a child entity, the child entity is not given in json but in an IRI format so this means that we get "/api/locations/1" instead of a JSON Object. I have been trying for hours but can't figure out how to change this. We are using annotations for the routes and the database relations.
You can use some nice tool like POSTMAN.
Then you can see the JSON response pretty printed.
You have to use the same, common normalization group for all embeded entities as desribed in docs.
The same is required for GraphQL when you need embeded fields other than id - asking for more than available results "Internal server error" "Cannot return null for non-nullable field XXX.YYY" - using GraphiQL helps with debugging more than POSTMAN (great tool) - when GraphQL will be working as expected, REST should be OK, too.
Unfortunatelly standard admin-on-rest doesn't like 'already fetched' values, expecting strings/IRIs only, not objects.
You can choose the response content type:

API-PLATFORM - model with object serialized to string at endpoint

I faced the problem with generating React components with api-platform-generate-crud.
Model has property that is object email.
I have serializer that make my email object a string.
API endpoint is serving string.
It works for GET & POST.
When I try to generate React components error message is
TypeError: Cannot read property '0' of undefined
Looking deeper into it, looks like that generator still see my email as object not a string.
Any idea how I can force API to 'see' email property as string not object ?
The data model you define is authoritative. Types in the Hydra documentation reflect the ones in PHP classes.
Here, the email property is of type object. If you set the related data as a string somewhere, you don't respect this contract anymore. The Hydra documentation is not in sync with the returned data.
You can change the type of the email property in the Hydra documentation by decorating the api_platform.hydra.normalizer.documentation service.
But I would recommend to keep the PHP classes' structure of your entities as close as possible of the structure exposed through the API.
Your classes should reflect the output of the API. You can use custom data providers to deal with more complex data structure (ex: ORM entities) before hydrating the structure to expose.

Alfresco Java backed web-script lookup by cmis:objectId

I am writing my first java-backed webscript for Alfresco community edition. I am implementing document properties / preview service, and I take a parameter which is the cmis:objectId of the document in question. I'm having trouble getting started because I haven't been able to access the document based on the cmis id.
What is the best way to get a document (NodeRef?) based on the cmis:objectId when operating server-side in a web-script controller? I see Jeff Potts' great examples on how to implement web scripts, but the mixing of the Java API and CMIS concepts has me stuck. Should I just use the search service and find the object based on the cmis:objectId property? Any pointers appreciated.
Well, the answer is a little ugly, but hopefully this helps someone...
A good way to look up the NodeRef using an 'opaque' objectId should be to use CMISServices, obtained from the registry in your java backed web script, i.e.
docRef = registry.getCMISService().getLatestVersion(docIdStr, false);
Unfortunately, there's a bug in the Alfresco code (or so it seems to me, admittedly a bit of a newbie). The alfresco CMISServicesImpl.getLatestVersion() uses a getObject() method under the covers. That method takes an objectId String as a parameter, but then strips off the version information at the end (i.e. the ";1.0" part of the objectId) and then checks to see if the remaining string is a valid NodeRef. In doing so, it checks it against this pattern (in NodeRef.java):
private static final Pattern nodeRefPattern = Pattern.compile(".+://.+/.+");
If the validation fails, you get a CMISInvalidArgumentException, with a message that xxxxx "is not an object ID".
So, to make a long story short, when I call the web script using a parameter for the objectId like this:
29ea5a16-12a8-497d-aad3-f43969e8a672;1.0
I get the CMIS exception. But, if I call the method with an objectId parameter that looks like this:
workspace://SpacesStore/29ea5a16-12a8-497d-aad3-f43969e8a672;1.0
... then, the "CMIS" lookup succeeds and I get my desired NodeRef back. Of course, all that the CMIS services are doing under the covers is stripping off the ";1.0" from the object ID, treating it as a NodeRef string, and doing the lookup using that.
In other words, you can't do it the right way in 4.2. The best thing to do is as #Gagravarr says and tweak your own objectId string to turn it into a NodeRef. Hopefully it's fixed in 5.x.

Creating custom objects for wcf

I have an existing web application that uses EF and POCO objects. I want to improve the client experience by exposing some of my objects through WCF(JSON). I have this working fine but where I am unsure is how to handle derived objects(not sure if that is the correct term) or IEnumerable anonymous objects if you will.
Let's say I have 3 tables structured like so:
Templates
ID
Template
Groups
ID
Group
Instances
ID
TemplateID
GroupID
This is obviously a one-to-many type relationship. I have my navigation properties setup correctly and getting strongly typed object properties works great. However, how do I send serialized anonymous type object(s) over the wire. Like an object that sends all instances that are equal to groupid=1 and include the names of the template and the object.
Am I missing something or do I have to create another class object for WCF that would look like this:
WCF Object
InstanceID
TemplateID
TemplateName
GroupID
GroupName
I guess I could alter my tables to account for this but that seems wrong too. I know that IEnumerable objects can't be serialized and I know that throw away objects are probably not the way to go either. I want to do this the right way but I am not sure how to go about it.
Your suggestions are appreciated.
Regards
Based on what you're doing, I'd suggest looking at OData with WCF Data Services. You state that you want to be able to send all instances where the groupid=1 - OData is great at this type of filtering.
If you're want to stick with your current approach and not use OData, then my first question is why are you sending back anonymous types at all? You can do what you are seeking (all instances with a groupid=1) without sending back an anonymous type. In your select clause you just create new instances of your concrete objects rather than newing up anonymous types. If your query is really just filtering and not executing any meaningful projection with the selct to anonymous type, then I don't see any reason to send back your anonymous type at all.

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