I'm using HOCON to configure log messages and I'm looking for a way to substitute placeholder values dynamically.
I know that ${?PLACEHOLDER} will read an environment variable and returns an empty string when the PLACEHOLDER environment variable doesn't exist.
Example
This is an example of what I had in mind:
(I'm using config4k to load HOCON )
data class LogMessage(val message: String, val code: String)
fun getMessage(key: String, placeholderValues: Array<String> = arrayOf()): LogMessage {
val config = ConfigFactory.parseString("MY_LOG_MESSAGE {code = ABC-123456, message = My log message with dynamic value %0% and another dynamic value %1% }")
val messageObject = config.extract<LogMessage>(key)
var message = messageObject.message
placeholderValues.forEachIndexed { placeholderIndex, value ->
message = message.replace("%$placeholderIndex%", value)
}
return messageObject.copy(message = message)
}
fun main(args: Array<String>) {
println(getMessage("MY_LOG_MESSAGE", arrayOf("value 1", "value 2")))
// prints: LogMessage(message=My log message with dynamic value value 1 and another dynamic value value 2, code=ABC-123456)
}
Even though this works, it doesn't look like the best solution and I assume there already is a solution for this.
Could someone tell me if there is a built-in solution?
First things first.
HOCON is just a glorified JSON format.
config4k is just a wrapper.
All your work is being done by Typesafe Config, as you've probably noticed.
And judging by their documentation and code, they support placeholders only from withing the file, or from the environment:
This library limits itself to config files. If you want to load config
from a database or something, you would need to write some custom
code.
But for what you're doing, simple String.format() should be enough:
fun interpolate(message: String, vararg args: Any) = String.format(message, *args)
println(interpolate("My message was %s %s %s %s", "a", 1, 3.32, true))
// My message was a 1 3.32 true
Notice that you can use * to destructure your array.
Related
How to populate the value of this variable:
private val _urlList = MutableLiveData<List<Url>>()
of type Url:
data class Url(
val imgSrcUrl: String
)
with the incoming list of url strings from a firebase call?
Here is where the magic happens:
private fun getData(){
viewModelScope.launch {
try {
getImagesUrl {
"Here where I need to set the value of the variable to a listOf(it) with it being strings
of urls retrieved from firebase storage"
}
}catch (e: Exception){
"Handling the error"
}
}
}
Edit
The map function #dominicoder provided solved my problem, answer accepted.
Thank you all for your help
Your question is unclear because you're showing a live data of a single Url object but asking to stuff it with a list of strings. So first, your live data object needs to change to a list of Urls:
private val _urlList = MutableLiveData<List<Url>>()
Then, assuming getImagesUrl yields a list of strings, if I understood you correctly, then you would map that to a list of Urls:
getImagesUrl { listOfImageUrlStrings ->
_urlList.value = listOfImageUrlStrings.map { imageUrlString -> Url(imageUrlString) }
}
If that does not answer your question, you really need to review it and clarify.
You can set values on the MutableLiveDataObject in two ways (depends on what you're doing).
Setting the value as normal from the UI thread can be done with:
myLiveData.value = myobject
If you're setting it from a background thread like you might in a coroutine with a suspended function or async task etc then use:
myLiveData.postValue(myObject)
It's not clear from your question whether the LiveData is meant to hold a list as you mention both lists and single values. But your LiveData holds a set the values as a collection like a list, set or map. It's can be treated as a whole object so adding a value later needs to have the whole collection set again like:
myLiveData.value = mutableListOf<Url>()
//Response received and object created
myLiveData.value = myLiveData.value.apply {
add(myObject)
}
Or if the value is mutable updating the existing value (preferred as it's cleaner):
myLiveData.value.add(myObject)
The problem with that approach is you're exposing the map as a mutable/writeable object. Allowing accessors to change the values which you might not want.
I have following code
val getContent = registerForActivityResult(ActivityResultContracts.GetContent()) { uri: Uri? ->
//Some code here..
}
and somewhere else ,
getContent.launch("application/vnd.openxmlformats-officedocument.wordprocessingml.document")
I can successfully select the docx file . I need to select either pdf or doc or text or docx rather just to be able to select one kind(here docx).
I would recommend using OpenDocument instead of GetContent.
val documentPick =
registerForActivityResult(ActivityResultContracts.OpenDocument()) { result ->
// do something
}
While launching the intent just add the mime types you want to get
documentPick.launch(
arrayOf(
"application/pdf",
"application/msword",
"application/ms-doc",
"application/doc",
"application/vnd.openxmlformats-officedocument.wordprocessingml.document",
"text/plain"
)
)
Using array doesn't work in my case. Instead, the following worked correctly.
Here custom class of ActivityResultContracts.GetContent is used. fun "createIntent" is overrided to customize method to make intent from the input.
// custom class of GetContent: input string has multiple mime types divided by ";"
// Here multiple mime type are divided and stored in array to pass to putExtra.
// super.createIntent creates ordinary intent, then add the extra.
class GetContentWithMultiFilter:ActivityResultContracts.GetContent() {
override fun createIntent(context:Context, input:String):Intent {
val inputArray = input.split(";").toTypedArray()
val myIntent = super.createIntent(context, "*/*")
myIntent.putExtra(Intent.EXTRA_MIME_TYPES, inputArray)
return myIntent
}
}
// define ActivityResultLauncher to launch : using custom GetContent
val getContent=registerForActivityResult(GetContentWithMultiFilter()){uri ->
... // do something
}
// launch it
// multiple mime types are separated by ";".
val inputString="audio/mpeg;audio/x-wav;audio/wav"
getContent.launch(inputString)
I'm trying to generate a YAML file from an input Map I'm using Jackson and the YamlFactory utility provided by Jackson to do so. I'm attempting to configure the indentation property for the YAML output, but it doesn't seem like that's being respected at all.
Here's how my code looks like:
fun getSdkResultAsGenericObject(sdkResult: Any?): Any? {
if (sdkResult == null) {
return null
}
var genericObj: Any?
val stringified = genericSdkObjectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(sdkResult)
.replace("\n", "")
val isArray = stringified.startsWith("[")
genericObj = if (isArray) {
genericSdkObjectMapper.readValue(stringified, List::class.java)
} else {
genericSdkObjectMapper.readValue(stringified, LinkedHashMap::class.java)
}
val defaultYaml = resultYamlMapper.writerWithDefaultPrettyPrinter().writeValueAsString(genericObj )
}
The declaration of the resultYamlMapper is like this:
val yamlFactory = YAMLFactory()
.configure(YAMLGenerator.Feature.SPLIT_LINES, false)
.configure(YAMLGenerator.Feature.INDENT_ARRAYS, true)
val resultYamlMapper = ObjectMapper(YamlFactory())
The documentation says that the INDENT_ARRAYS feature uses 2 spaces by default. I'm trying to understand how I can configure that? I need 4 spaces in the resultant YAML. I tried setting a pretty print writer:
val yamlFactory = YAMLFactory()
.configure(YAMLGenerator.Feature.SPLIT_LINES, false)
.configure(YAMLGenerator.Feature.INDENT_ARRAYS, true)
val resultYamlMapper = ObjectMapper(YamlFactory())
val arrayIndenter = DefaultIndenter(" ", DefaultIndenter.SYS_LF)
val objectIndenter = DefaultIndenter(" ", DefaultIndenter.SYS_LF)
resultYamlMapper.setDefaultPrettyPrinter(DefaultPrettyPrinter().withObjectIndenter(objectIndenter).withArrayIndenter(arrayIndenter))
But this doesn't seem to be respected at all. Any thoughts? Or does Jackson not let you configure the indentation at all?
The docs show that the PrettyPrinter interface is only for the JsonGenerator.
If you want to customize your YAML output, you have to use the SnakeYAML API directly (which is used by Jackson for YAML processing). SnakeYAML has similar features to Jackson and there is little reason to use Jackson if you only want to process YAML. Most importantly, it lets you configure YAML formatting.
I'd like to be able to use Micronaut's declarative client to hit an a different endpoint based on whether I'm in a local development environment vs a production environment.
I'm setting my client's base uri in application.dev.yml:
myserviceclient:
baseUri: http://localhost:1080/endpoint
Reading the docs from Micronaut, they have the developer jumping through quite a few hoops to get a dynamic value piped into the actual client. They're actually quite confusing. So I've created a configuration like this:
#ConfigurationProperties(PREFIX)
class MyServiceClientConfig {
companion object {
const val PREFIX = "myserviceclient"
const val BASE_URL = "http://localhost:1080/endpoint"
}
var baseUri: String? = null
fun toMap(): MutableMap<String, Any> {
val m = HashMap<String, Any>()
if (baseUri != null) {
m["baseUri"] = baseUri!!
}
return m
}
}
But as you can see, that's not actually reading any values from application.yml, it's simply setting a const value as a static on the class. I'd like that BASE_URL value to be dynamic based on which environment I'm in.
To use this class, I've created a declarative client like this:
#Client(MyServiceClientConfig.BASE_URL)
interface MyServiceClient {
#Post("/user/kfc")
#Produces("application/json")
fun sendUserKfc(transactionDto: TransactionDto)
}
The docs show an example where they're interpolating values from the config map that's built like this:
#Get("/api/\${bintray.apiversion}/repos/\${bintray.organization}/\${bintray.repository}/packages")
But how would I make this work in the #Client() annotation?
Nowhere in that example do they show how bintray is getting defined/injected/etc. This appears to be the same syntax that's used with the #Value() annotation. I've tried using that as well, but every value I try to use ends up being null.
This is very frustrating, but I'm sure I'm missing a key piece that will make this all work.
I'm setting my client's base uri in application.dev.yml
You probably want application-dev.yml.
But how would I make this work in the #Client() annotation?
You can put a config key in the #Client value using something like #Client("${myserviceclient.baseUri}").
If you want the url somewhere in your code use this:
#Value("${micronaut.http.services.occupancy.urls}")
private String occupancyUrl;
first, I create empty Array(Kotlin) instance in companion object.
companion object {
var strarray: Array<String> = arrayOf()
var objectarray: LinkedHashMap<Int, List<Any>> = LinkedHashMap<Int, List<Any>>()
}
and I expected that I use empty array instance when read textString from CSV File.
fun csvFileToString():String {
val inputStream = File(Paths.get("").toAbsolutePath().toString()
.plus("/src/main/SampleCSVFile_2kb.csv")).inputStream()
val reader = inputStream.bufferedReader()
var iterator = reader.lineSequence().iterator()
var index:Int = 1;
while (iterator.hasNext()){
var lineText:String = iterator.next()
strarray.set(index, lineText)
index++
}
return ""
}
but when I run that source code
a.csvFileToString()
println(CsvParser.strarray)
occured exception
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 1
strarray.set(index, lineText) <<<<<<<<< because of this line
can I use Array(from kotlin collection) like ArrayList(from java collection)?
You can add a new item to an array using +=, for example: item += item
private var songs: Array<String> = arrayOf()
fun add(input: String) {
songs += input
}
Size of Array is defined at its creation and cannot be modified - in your example it equals 0.
If you want to create Array with dynamic size you should use ArrayList.
arrayOf gives you an array. Arrays have fixed length even in Java.
listOf gives you an immutable list. You cannot add or remove items in this list.
What you're looking for is mutableListOf<String>.
In your current approach, reusing a member property, don't forget to clear the list before every use.
Your code can be further simplified (and improved) like so:
out.clear()
inputStream.bufferedReader().use { reader -> // Use takes care of closing reader.
val lines = reader.lineSequence()
out.addAll(lines) // MutableList can add all from sequence.
}
Now imagine you wanted to consume the output list but needed to parse another file at the same time.
Consider working towards a pure function (no side effects, for now no accessing member properties) and simplifying it even further:
fun csvFileToString(): String { // Now method returns something useful.
val inputStream = File(Paths.get("").toAbsolutePath().toString()
.plus("/src/main/SampleCSVFile_2kb.csv")).inputStream()
inputStream.bufferedReader().use {
return it.lineSequence().joinToString("\n")
}
}
In this case we can totally skip the lists and arrays and just read the text:
inputStream.bufferedReader().use {
return it.readText()
}
I'm assuming that's what you wanted in the first place.
Kotlin has a lot of useful extension functions built-in. Look for them first.