I would like to dynamically decide what's the type of the object JMS Serializer is just about to serialize.
For example, I have two properties, one for storing the discount value, and another one for discount type. If discount type is 0, then discount value is just number (meaning "this number of percent you receive as disocunt"). For discount_type = 1, you will have Money object in the discount_value (Money object is amount and currency).
The output should be following:
{
...
discounts: [
{
value: 10,
type: 0
},
{
value: {
money_value: 50,
money_currency: EUR
},
type: 1
}
]
}
Is there a way to do that? I need defined type in Entity.Class.yml as I need to do some deserialization later.
For this case you could try using #Discrimantor annotation.
So that you could have some abstract discount value class and two descendants of it with different fields and mapping.
Related
Introduction
Let's say I have a Kotlin enum class:
enum class Type {
ONE,
TWO,
THREE,
FOUR
}
and a following data class:
data class Item(
val name: String,
val type: Type
)
Then I have a Single that emits a list of Items – can by anything but for example purposes, let's say it looks like that:
val itemsSingle = Single.just(listOf(
Item("A", Type.ONE),
Item("B", Type.ONE),
Item("C", Type.TWO),
Item("D", Type.THREE),
))
Problem
What I'd like to achieve is to have an RxJava stream that will output a map where keys come from Type and values are lists of Items matching a given Type value (where an undetermined, unsorted list of Items is provided by some other Single stream). The signature would be:
Single<Map<Type, List<Item>> // or Observable<Map<Type, List<Item>>
One additional requirement is that the map's keys should always exhaust all values from Type enum even if the itemsSingle stream contains no items for some Type values (or no items at all). So, for the provided itemsSingle example stream the returned map should look like this:
{
ONE: [ Item(name: "A", type: ONE), Item(name: "B", type: ONE) ],
TWO: [ Item(name: "C", type: TWO) ],
THREE: [ Item(name: "D", type: THREE) ],
FOUR: []
}
Attempt
With all the above, I've kinda achieved the desired result with following steps:
To satisfy the requirement of exhausting all Type enum values I first create a map that has an empty list for all possible Type values:
val typeValuesMap = Type.values().associate { it to emptyList<Item>() }
val typeValuesMapSingle = Single.just(typeValuesMap)
// result: {ONE=[], TWO=[], THREE=[], FOUR=[]}
I can get a map that contains items from itemsSingle grouped under respective Type value keys:
val groupedItemsMapSingle = itemsSingle.flattenAsObservable { it }
.groupBy { it.type }
.flatMapSingle { it.toList() }
.toMap { list -> list[0].type } // the list is guaranteed to have at least one item
// result: {ONE=[Item(name=A, type=ONE), Item(name=B, type=ONE)], THREE=[Item(name=D, type=THREE)], TWO=[Item(name=C, type=TWO)]}
finally I can combine both lists using the combineLatest operator and overwriting initial empty list of items for a given Type value if itemsSingle contained any Items for this Type value:
Observable.combineLatest(
typeValuesMapSingle.flattenAsObservable { it.entries },
groupedItemsMapSingle.flattenAsObservable { it.entries }
) { a, b -> listOf(a, b) }
.defaultIfEmpty(typeValuesMap.entries.toList()) // in case itemsSingle is empty
.flatMapIterable { it }
.collect({mutableMapOf<Type, List<Item>>()}, { a, b -> a[b.key] = b.value})
// result: {FOUR=[], ONE=[Item(name=A, type=ONE), Item(name=B, type=ONE)], THREE=[Item(name=D, type=THREE)], TWO=[Item(name=C, type=TWO)]}
Summary
As you can see, it's quite a lot of code for a seemingly simple operation. So my question is – is there a simpler way to achieve the result I'm after?
Just merge a map of empty lists with a map of filled lists
val result = itemsSingle.map { items->
Type.values().associateWith { listOf<Item>() } + items.groupBy { it.type }
}
I am using Karate version 0.8.0.1 and I want to perform following steps to test some responses.
I make a Get to web service 1
find the value for currencies from the response of web service 1 using jsonpath: $.currencies
Step 2 gives me following result: ["USD","HKD","SGD","INR","GBP"]
Now I use Get method for web service 2
From the response of web service 2 I want to get the value of price field with json-path something like below(passing the values from step 3 above):
$.holding[?(#.currency=='USD')].price
$.holding[?(#.currency=='HKD')].price
$.holding[?(#.currency=='SGD')].price
$.holding[?(#.currency=='INR')].price
$.holding[?(#.currency=='GBP')].price
So there are so many currencies but I want to verify price for only the currencies returned by web service 1(which will be always random) and pass it on to the the output of web service 2 to get the price.
Once i get the price I will match each price value with the value returned from DB.
I am not sure if there is any simple way in which I can pass the values returned by service 1 into the json-path of service 2 one by one and get the results required. Any suggestions for doing this will be helpful As this will be the case for most of the web services I will be automating.
There are multiple ways to do this in Karate. The below should give you a few pointers. Note how there is a magic variable _$ when you use match each. And since you can reference any other JSON in scope, you have some very powerful options.
* def expected = { HKD: 1, INR: 2, USD: 3}
* def response1 = ['USD', 'HKD', 'INR']
* def response2 = [{ currency: 'INR', price: 2 }, { currency: 'USD', price: 3 }, { currency: 'HKD', price: 1 }]
* match response2[*].currency contains only response1
* match each response2 contains { price: '#(expected[_$.currency])' }
You probably already have seen how you can call a second feature file in a loop which may be needed for your particular use case. One more piece of the puzzle may be this - it is very easy to transform any JSON array into the form Karate expects for calling a feature file in a loop:
* def response = ['USD', 'HKD', 'INR']
* def data = karate.map(response, function(x){ return { code: x } })
* match data == [{code: 'USD'}, {code: 'HKD'}, {code: 'INR'}]
EDIT - there is a short-cut to convert an array of primitives to an array of objects now: https://stackoverflow.com/a/58985917/143475
Also see this answer: https://stackoverflow.com/a/52845718/143475
I have a use case where my data store has an array of products, each with a price and quantity.
What I would like to do is calculate the 'total' for each product (price x quantity). I can do so by created a new computed property which re-calculates the entire array, appending a new property with the total.
The issue is, this requires recalculating every item in the array every time a single item changes.
I could use a component to calculate and display, but I also need to calculate a total (which is the sum of all computed prices on each product).
Is there a more efficient way to do this?
[
{
"Product ID": 1,
"Price": 10,
"Quantity": 5,
"Calculated Total": 50
},
{
"Product ID": 2,
"Price": 12,
"Quantity": 10,
"Calculated Total": 120
}
]
You can use a computed value to map through the original array and sum the values. e.g say the original array is named originalArray, do:
computed: {
computedTotal() {
let sum = 0
originalArray.map(item => sum += item["Calculated Total"])
return sum
}
}
I have a problem when querying mongoDB with nested objects notation:
db.messages.find( { headers : { From: "reservations#marriott.com" } } ).count()
0
db.messages.find( { 'headers.From': "reservations#marriott.com" } ).count()
5
I can't see what I am doing wrong. I am expecting nested object notation to return the same result as the dot notation query. Where am I wrong?
db.messages.find( { headers : { From: "reservations#marriott.com" } } )
This queries for documents where headers equals { From: ... }, i.e. contains no other fields.
db.messages.find( { 'headers.From': "reservations#marriott.com" } )
This only looks at the headers.From field, not affected by other fields contained in, or missing from, headers.
Dot-notation docs
Since there is a lot of confusion about queries MongoDB collection with sub-documents, I thought its worth to explain the above answers with examples:
First I have inserted only two objects in the collection namely: message as:
> db.messages.find().pretty()
{
"_id" : ObjectId("5cce8e417d2e7b3fe9c93c32"),
"headers" : {
"From" : "reservations#marriott.com"
}
}
{
"_id" : ObjectId("5cce8eb97d2e7b3fe9c93c33"),
"headers" : {
"From" : "reservations#marriott.com",
"To" : "kprasad.iitd#gmail.com"
}
}
>
So what is the result of query: db.messages.find({headers: {From: "reservations#marriott.com"} }).count()
It should be one because these queries for documents where headers equal to the object {From: "reservations#marriott.com"}, only i.e. contains no other fields or we should specify the entire sub-document as the value of a field.
So as per the answer from #Edmondo1984
Equality matches within sub-documents select documents if the subdocument matches exactly the specified sub-document, including the field order.
From the above statements, what is the below query result should be?
> db.messages.find({headers: {To: "kprasad.iitd#gmail.com", From: "reservations#marriott.com"} }).count()
0
And what if we will change the order of From and To i.e same as sub-documents of second documents?
> db.messages.find({headers: {From: "reservations#marriott.com", To: "kprasad.iitd#gmail.com"} }).count()
1
so, it matches exactly the specified sub-document, including the field order.
For using dot operator, I think it is very clear for every one. Let's see the result of below query:
> db.messages.find( { 'headers.From': "reservations#marriott.com" } ).count()
2
I hope these explanations with the above example will make someone more clarity on find query with sub-documents.
The two query mechanism work in different ways, as suggested in the docs at the section Subdocuments:
When the field holds an embedded document (i.e, subdocument), you can either specify the entire subdocument as the value of a field, or “reach into” the subdocument using dot notation, to specify values for individual fields in the subdocument:
Equality matches within subdocuments select documents if the subdocument matches exactly the specified subdocument, including the field order.
In the following example, the query matches all documents where the value of the field producer is a subdocument that contains only the field company with the value 'ABC123' and the field address with the value '123 Street', in the exact order:
db.inventory.find( {
producer: {
company: 'ABC123',
address: '123 Street'
}
});
Basically, without knowing before hand what the resulting structure of a query might be, I'd like to query the database, and return a structure like this (json-y)
// Rows
[
// Row 1
[
{ ColumnName: "id", Value: 1, Type: int },
{ ColumnName: "name", Value: "batman", Type: string },
...
],
// Row 2
[
{ ColumnName: "id", Value: 2, Type: int },
{ ColumnName: "name", Value: "superman", Type: string },
...
]
]
Is there a way to get the Type for a Column using package database/sql in golang?
I'm suspecting that what I want to do is
make an array of interface{} the size of Column(),
then for each column determine it's type,
then fill the array with a pointer to that type,
and then pass the array to Scan()
Which is a little like this code example from sqlx, but without first knowing the Struct that the data would be populating.
You should be able to do it this way:
func printRows(rows *sql.Rows){
colTypes, err := rows.ColumnTypes()
for _,s := range colTypes {
log.Println("cols type:", s.DatabaseTypeName());
}
}
Using database/sql? No (as far as I know).
But you can use this code for arbitrary queries. And json.Marshall() from the json package will use reflection to determine the right way to print a value, so you could have a structure like this:
type Column struct {
ColumnName string
ColumnValue interface{}
ColumnType string
}
And then use reflect.TypeOf(someVariable).String() to get the type for ColumnType.