I would like to know how to restrict the possible values in a field in prisma.
My model looks like this currently
model FraudOrderCheck {
id Int #id #default(autoincrement())
brand_name String
retries Int #default(0)
validation_state String #default('processing')
}
How to restrict the possible values in validation_state to this
validation_state String #default('processing') // processed, errored
Prisma cannot restrict string values at the moment. You would need to handle this in your application logic.
Another workaround would be to use enums:
enum ValidationState {
PROCESSING
PROCESSED
ERROR
}
Related
I have the following value object code which validates CustCode by some expensive database operations.
public class CustCode : ValueObject<CustCode>
{
private CustCode(string code) { Value = code; }
public static Result<CustCode> Create(string code)
{
if (string.IsNullOrWhiteSpace(code))
return Result.Failure<CustCode>("Code should not be empty");
// validate if the value is still valid against the database. Expensive and slow
if (!ValidateDB(code)) // Or web api calls
return Result.Failure<CustCode>("Database validation failed.");
return Result.Success<CustCode>(new CustCode(code));
}
public string Value { get; }
// other methods omitted ...
}
public class MyEntity
{
CustCode CustCode { get; }
....
It works fine when there is only one or a few entity instances with the type. However, it becomes very slow for method like GetAll() which returns a lot of entities with the type.
public async IAsyncEnumerable<MyEntity> GetAll()
{
string line;
using var sr = File.OpenText(_config.FileName);
while ((line = await sr.ReadLineAsync()) != null)
{
yield return new MyEntity(CustCode.Create(line).Value); // CustCode.Create called many times
}
}
Since data in the file was already validated before saving so it's actually not necessary to be validated again. Should another Create function which doesn't validate the value to be created? What's the DDD idiomatically way to do this?
I generally attempt not to have the domain call out to retrieve any additional data. Everything the domain needs to do its job should be passed in.
Since value objects represent immutable state it stands to reason that once it has managed to be created the values are fine. To this end perhaps the initial database validation can be performed in the integration/application "layer" and then the CustCode is created using only the value(s) provided.
Just wanted to add an additional point to #Eben Roux answer:
In many cases the validation result from a database query is dependent on when you run the query.
For example when you want to check if a phone number exists or if some product is in stock. The answers to those querys can change any second, and though are not suited to allow or prevent the creation of a value object.
You may create a "valid" object, that is (unknowingly) becoming invalid in the very next second (or the other way around). So why bother running an expensive validation, if the validation result is not reliable.
The requirement is to store the hardcoded value for varchar which is in an entity file(.eti). I tried adding to the default option but it is not reflecting.
Default option works well with boolean values (true/false), typelists (you can choose a default typecode), monetary amounts too, but it looks like it is not allowed to specify a default varchar.
Therefore the easiest way would be to create a preupdate rule which inserts that default value every time when you create a new record in the database.
Preupdate rule example:
#gw.rules.RuleName("YourEntityAssignDefaultValue")
internal class YourEntityAssignDefaultValueRule {
static function doCondition(yourEntity : entity.YourEntity) : boolean {
return yourEntity.New
}
static function doAction(yourEntity : entity.YourEntity, actions : gw.rules.Action) {
yourEntity.yourColumn = "defaultValue"
}
}
you can achieve through getter and setter properties in an appropriate enhancement class.
public property get PolicyNumber(): String {
return this.PolicyNumber }
and somewhere class you must be assigned the value to the PolicyNumber field then it will reflect.
So, I'm working with ServiceStack, and know my way around a bit with it. I've used AutoQuery and find it indispensable when calling for straight 'GET' messages. I'm having an issue though, and I have been looking at this for a couple of hours. I hope it's just something I'm overlooking.
I have a simple class set up for my AutoQuery message:
public class QueryCamera : QueryDb<db_camera>
{
}
I have an OrmLite connection that is used to retrieve db_camera entires from the database. this all works just fine. I don't want to return a model from the database though as a result, I'd like to return a DTO, which I have defined as another class. So, using the version of QueryDb, my request message is now this:
public class QueryCamera : QueryDb<db_camera, Camera>
{
}
Where the Camera class is my DTO. The call still executes, but I get no results. I have a mapper extension method ToDto() set up on the db_camera class to return a Camera instance.
Maybe I'm just used to ServiceStack making things so easy... but how do I get the AutoQuery request above to perform the mapping for my request? Is the data retrieval now a manual operation for me since I'm specifying the conversion I want? Where's the value in this type being offered then? Is it now my responsibility to query the database, then call .ToDto() on my data model records to return DTO objects?
EDIT: something else I just observed... I'm still getting the row count from the returned dataset in AutoQueryViewer, but the field names are of the data model class db_camera and not Camera.
The QueryDb<From, Into> isn't able to use your Custom DTO extension method, it's used to select a curated set of columns from the executed AutoQuery which can also be used to reference columns on joined tables.
If you want to have different names on the DTO than on your Data Model, you can use an [Alias] attribute to map back to your DB column name which will let you name your DTO Property anything you like. On the other side you can change what property the DTO property is serialized as, e.g:
[DataContract]
public class Camera
{
[DataMember(Name = "Id")] // serialized as `Id`
public camera_id { get; set; } // populated with db_camera.camera_id
[DataMember]
[Alias("model")] // populated with db_camera.model
public CameraModel { get; set; } // serialized as `CameraModel`
}
I have a rule that looks like this:
INTEGER : [0-9]+;
myFields : uno=INTEGER COMMA dos=INTEGER
Right now to access uno I need to code:
Integer i = Integer.parseInt(myFields.uno.getText())
It would be much cleaner if I could tell antler to do that conversion for me; then I would just need to code:
Integer i = myFields.uno
What are my options?
You could write the code as action, but it would still be explicit conversion (eventually). The parser (like every parser) parses the text and then it's up to "parsing events" (achieved by listener or visitor or actions in ANTLR4) to create meaningful structures/objects.
Of course you could extend some of the generated or built-in classes and then get the type directly, but as mentioned before, at some point you'll always need to convert text to some type needed.
A standard way of handling custom operations on tokens is to embed them in a custom token class:
public class MyToken extends CommonToken {
....
public Integer getInt() {
return Integer.parseInt(getText()); // TODO: error handling
}
}
Also create
public class MyTokenFactory extends TokenFactory { .... }
to source the custom tokens. Add the factory to the lexer using Lexer#setTokenFactory().
Within the custom TokenFactory, override the method
Symbol create(int type, String text); // (typically override both factory methods)
to construct and return a new MyToken.
Given that the signature includes the target token type type, custom type-specific token subclasses could be returned, each with their own custom methods.
Couple of issues with this, though. First, in practice, it is not typically needed: the assignment var is statically typed, so as in the the OP example,
options { TokenLabelType = "MyToken"; }
Integer i = myFields.uno.getInt(); // no cast required
If Integer is desired & expected, use getInt(). If Boolean ....
Second, ANTLR options allows setting a TokenLabelType to preclude the requirement to manually cast custom tokens. Use of only one token label type is supported. So, to use multiple token types, manual casting is required.
In jcouchdb I used to extend BaseDocument and then, in a transparent manner, mix Annotations and not declared fields.
Example:
import org.jcouchdb.document.BaseDocument;
public class SiteDocument extends BaseDocument {
private String site;
#org.svenson.JSONProperty(value = "site", ignoreIfNull = true)
public String getSite() {
return site;
}
public void setSite(String name) {
site = name;
}
}
and then use it:
// Create a SiteDocument
SiteDocument site2 = new SiteDocument();
site2.setProperty("site", "http://www.starckoverflow.com/index.html");
// Set value using setSite
site2.setSite("www.stackoverflow.com");
// and using setProperty
site2.setProperty("description", "Questions & Answers");
db.createOrUpdateDocument(site2);
Where I use both a document field (site) that is defined via annotation and a property field (description) not defined, both get serialized when I save document.
This is convenient for me since I can work with semi-structured documents.
When I try to do the same with Ektorp I have documents using annotations and Documents using HashMap BUT I couldn't find an easy way of getting the mix of both (I've tried using my own serializers but this seems to much work for something that I get for free in jcouchdb). Also tried to annotate a HashMap field but then is serialized as an object and I get the fields automatically saved BUT inside an object with the name of the HashMap field.
Is it possible to do (easily/for free) using Ektorp?
It is definitely possible. You have two options:
Base your class on org.ektorp.support.OpenCouchDbDocument
Annotate the you class with #JsonAnySetter and #JsonAnyGetter. Red more here: http://wiki.fasterxml.com/JacksonFeatureAnyGetter