I am using ws-lite to automate web service testing, and I want to have more flexible control over the xm l request generated.
Basically the request body is a groovy closure that will be passed to MarkupBuilder in order to create the SOAP message.
Here is an example of what I am trying to achieve (example taken from https://github.com/jwagenleitner/groovy-wslite):
#Grab(group='com.github.groovy-wslite', module='groovy-wslite', version='1.1.0')
import wslite.soap.*
def client = new SOAPClient('http://www.holidaywebservice.com/Holidays/US/Dates/USHolidayDates.asmx')
def month = ["Feb"]
def response = client.send(SOAPAction:'http://www.27seconds.com/Holidays/US/Dates/GetMothersDay') {
body {
GetMothersDay('xmlns':'http://www.27seconds.com/Holidays/US/Dates/') {
year(2011)
month.each{ a = null ->
if (a != null){
"month"(a)
}
}
}
}
}
assert "2011-05-08T00:00:00" == response.GetMothersDayResponse.GetMothersDayResult.text()
assert 200 == response.httpResponse.statusCode
assert "ASP.NET" == response.httpResponse.headers['X-Powered-By']
The above example, I can create month tag fine with value/values specified.
But if I change it to be:
#Grab(group='com.github.groovy-wslite', module='groovy-wslite', version='1.1.0')
import wslite.soap.*
def client = new SOAPClient('http://www.holidaywebservice.com/Holidays/US/Dates/USHolidayDates.asmx')
def month_cl = { a -> "month"(a) }
def response = client.send(SOAPAction:'http://www.27seconds.com/Holidays/US/Dates/GetMothersDay') {
body {
GetMothersDay('xmlns':'http://www.27seconds.com/Holidays/US/Dates/') {
year(2011)
month_cl("Feb")
}
}
}
assert "2011-05-08T00:00:00" == response.GetMothersDayResponse.GetMothersDayResult.text()
assert 200 == response.httpResponse.statusCode
assert "ASP.NET" == response.httpResponse.headers['X-Powered-By']
I will have a missing method exception.
I don't quite understand why I can't just invoke a groovy closure like that?
Delegate of month_cl closure has to be set to the current/parent delegate (in this case it is closure passed as param to GetMothersDay). Try with:
body {
GetMothersDay('xmlns':'http://www.27seconds.com/Holidays/US/Dates/') {
year(2011)
month_cl.delegate = delegate
month_cl("Feb")
}
}
It's quite normal to get MissingMethodException, because the closure month_cl is calling month method which does not exist. To do this (in your way), you should pass a Closure c to month_cl and call it on the argument a, like this:
def month_cl = { a, Closure c -> c(a) }
and using the new implementation, month_cl("Feb") becomes month_cl("Feb") { "month" } which results to "month"("Feb").
Here is a working example:
#Grab(group='com.github.groovy-wslite', module='groovy-wslite', version='1.1.0')
import wslite.soap.*
def client = new SOAPClient('http://www.holidaywebservice.com/Holidays/US/Dates/USHolidayDates.asmx')
def months = ["Feb"]
def month_cl = { m, Closure c -> return c(m) }
def response = client.send(SOAPAction:'http://www.27seconds.com/Holidays/US/Dates/GetMothersDay') {
body {
GetMothersDay('xmlns':'http://www.27seconds.com/Holidays/US/Dates/') {
year(2011)
month_cl("Feb") { "month" } // -> month("Feb")
}
}
}
assert "2011-05-08T00:00:00" != response.GetMothersDayResponse.GetMothersDayResult.text()
assert 200 == response.httpResponse.statusCode
assert "ASP.NET" == response.httpResponse.headers['X-Powered-By']
Related
I have the following code that iterates recursively and does something over the network. As it goes over the network, I would like to do some optimizations, where the very first optimization would be to avoid going over the network for certain elements that I have already tried.
For example., in the case below, I call a URL, extract the HREF's found in that URL and call those URL's and report the status. As it could be possible that certain URL's might be fetched again, for those URL's that failed, I would like to add them to a global state so that when I encounter this URL the next time, I will avoid those network calls.
Here is the code:
def callURLWithCache(url: String): Task[HttpResult] = {
Task {
Http(url).timeout(connTimeoutMs = 1000, readTimeoutMs = 3000).asString
}.attempt.map {
case Left(err) =>
println(s"ERR happened ----------------- $url ************************ ${err.getMessage}")
// Add to the cache
val httpResult = HttpResult(source = url, isSuccess = false, statusCode = 1000, errorMessage = Some(err.getMessage))
val returnnnn: Try[Any] = httpResultErrorCache.put(url)(httpResult)
httpResult
case Right(doc) =>
if (doc.isError) {
HttpResult(source = url, isSuccess = doc.isSuccess, statusCode = doc.code)
} else {
val hrefs = (browser.parseString(doc.body) >> elementList("a[href]") >?> attr("href"))
.distinct.flatten.filter(_.startsWith("http"))
HttpResult(source = url, isSuccess = doc.isSuccess, statusCode = doc.code, elems = hrefs)
}
}
}
You can see in the case Left(....) block that I add the failed case class to the cache which I define globally on the enclosing class of this function as:
val underlyingCaffeineCache: cache.Cache[String, Entry[HttpResult]] = Caffeine.newBuilder().maximumSize(10000L).build[String, Entry[HttpResult]]
implicit val httpResultErrorCache: Cache[HttpResult] = CaffeineCache(underlyingCaffeineCache)
Here is the function that I do a recursive operation:
def parseSimpleWithFilter(filter: ParserFilter): Task[Seq[HttpResult]] = {
def parseInner(depth: Int, acc: HttpResult): Task[Seq[HttpResult]] = {
import cats.implicits._
if (depth > 0) {
val batched = acc.elems.collect {
case elem if httpResultErrorCache.get(elem).toOption.exists(_.isEmpty) =>
callURLWithCache(elem).flatMap(newElems => parseInner(depth - 1, newElems))
}.sliding(30).toSeq
.map(chunk => Task.parSequence(chunk))
Task.sequence(batched).map(_.flatten).map(_.flatten)
} else Task.pure(Seq(acc))
}
callURLWithCache(filter.url).map(elem => parseInner(filter.recursionDepth, elem)).flatten
}
It can be seen that I'm checking if the url that I have as my current elem is already in the cache, meaning that I have already tried it and failed, so I would like to avoid doing a HTTP call once again for it.
But what happens is that, the httpResultErrorCache turns up always empty. I'm not sure if the Task chunk is causing this behavior. Any ideas on how to get the cache to work?
I created a function that recieves input and compare it to a list, when find a match it return the match, in this case this match is the attribute of a class that i created.
I understand that the problem is with the return statement, so in the beginning of the function I declare the return as "Any", further more than that I'm kinda lost.
The error is this: A 'return' expression required in a function with a block body ('{...}')
class Class1(var self: String)
var test_class = Class1("")
fun giver(){
test_class.self = "Anything"
}
class Funciones(){
fun match_finder(texto: String): Any{
var lista = listOf<String>(test_class.self)
var lista_de_listas = listOf<String>("test_class.self")
var count = -1
for (i in lista_de_listas){
count = count + 1
if (texto == i){
lista_de_listas = lista
var variable = lista_de_listas[count]
return variable
}
}
}
}
fun main(){
giver()
var x = "test_class.self"
var funcion = Funciones()
var y = funcion.match_finder(x)
println(y)
}
To explain you what the problem is, let's consider the following code:
class MyClass {
fun doSomething(): String {
val numbers = listOf(1, 2, 3)
for (number in numbers) {
if (number % 2 == 0) {
return "There is at least one even number in the list"
}
}
}
}
If you try compiling it you'll get the same error message as in your question: A 'return' expression required in a function with a block body ('{...}'). Why is that?
Well, we defined a function doSomething returning a String (it could be any other type) but we're returning a result only if the list of numbers contains at least one even number. What should it return if there's no even number? The compiler doesn't know that (how could it know?), so it prompts us that message. We can fix the code by returning a value or by throwing an exception:
class MyClass {
fun doSomething(): String {
val numbers = listOf(1, 2, 3)
for (number in numbers) {
if (number % 2 == 0) {
return "There is at least one even number in the list"
}
}
// return something if the list doesn't contain any even number
return "There is no even number in the list"
}
}
The same logic applies to your original code: what should the function return if there is no i such that texto == i?
Please also note that the solution you proposed may be syntactically correct - meaning it compiles correctly - but will probably do something unexpected. The for loop is useless since the if/else statement will always cause the function to return during the first iteration, so the value "There is no match" could be returned even if a match actually exists later in the list.
I searched online, if someone has the same problem, the correct code is as follows:
class Funciones(){
fun match_finder(texto: String): Any{
var lista = listOf<String>(test_class.self)
var lista_de_listas = listOf<String>("test_class.self")
var count = -1
var variable = " "
for (i in lista_de_listas){
count = count + 1
if (texto == i){
lista_de_listas = lista
var variable = lista_de_listas[count]
return variable
} else {
return "There is no match"
}
}
return variable
}
}
I'm not seeing anything ever get returned by the scan. I know it's because the mutableList gets returned right away, but how do I block the return until the time expires?
Basically, all I want to do is fill up the mutable list for as long as the take() permits then return that mutableList to the calling function.
This is what I have tried.
private val timeoutScheduler: Scheduler = Schedulers.computation()
fun scanForAllDevicesStartingWith(devicePrefix: String): List<String> {
Log.d(TAG, "Scanning for devices starting with $devicePrefix")
val mutableList = mutableListOf<String>()
val result = scanForDevices()
.take(3, TimeUnit.SECONDS, timeoutScheduler)
.subscribe { scanResult ->
val name = scanResult.bleDevice.name
Logger.d(TAG, "Potential device named $name found")
if(name != null) {
if(name.startsWith(prefix = devicePrefix)) {
Logger.d(TAG, "Match found $name")
mutableList.plus(name)
}
}
}
return mutableList
}
private fun scanForDevices(): Observable<ScanResult>
= rxBleClient.scanBleDevices(
ScanSettings.Builder()
.setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY)
.setCallbackType(ScanSettings.CALLBACK_TYPE_ALL_MATCHES)
.build(),
ScanFilter.Builder()
.build())
}
OK, here it is boiled down for the next person who wants to do this kind of thing. In Rx, they have Singles which are Observables that just emit one value. In my case I needed a list of String values, so just need to use a Single of type List of type String. That gets just one element emitted that happens to be a list of Strings. The code looks like this...
fun returnAllDevicesStartingWith(devicePrefix: String): Single<List<String>> {
return scanForDevices()
.take(3, TimeUnit.SECONDS, timeoutScheduler)
.map { it.bleDevice.name }
.filter { it.startsWith(devicePrefix) }
.toList()
}
The function that calls it (written in Java instead of Kotlin) looks like this:
List<String> devices = bleUtility.returnAllDevicesStartingWith(prefix).blockingGet();
I tested it using a mocked function like this:
//Begin test code
var emittedList: List<String> = listOf("dev1-1", "dev1-2", "dev2-1", "dev2-2", "dev3-1", "dev3-2")
private fun scanForRoomDevices(): Observable<FoundDevice> = Observable
.intervalRange(0, emittedList.size.toLong(), 0, 1, TimeUnit.SECONDS, timeoutScheduler)
.map { index -> FoundDevice(emittedList[index.toInt()], BleDevice(emittedList[index.toInt()])) }
data class FoundDevice(val controllerId: String, val bleDevice: BleDevice)
data class BleDevice(val name: String)
Hope this helps others.
I'm getting frustrated trying to convert a small part of the Golang templating language to Scala.
Below are the key parts of the lex.go source code: https://github.com/golang/go/blob/master/src/text/template/parse/lex.go
The tests are here: https://github.com/golang/go/blob/master/src/text/template/parse/lex_test.go
Basically this "class" takes a string and returns an Array of "itemType". In the template string, the start and end of special tokens is using curly braces {{ and }}.
For for example:
"{{for}}"
returns an array of 4 items:
item{itemLeftDelim, 0, "{{" } // scala case class would be Item(ItemLeftDelim, 0, "")
item{itemIdentifier, 0, "for"}
item{itemRightDelim, 0, "}}"}
item{itemEOF, 0, ""}
The actual call would look like:
l := lex("for", `{{for}}`, "{{", "}}") // you pass in the start and end delimeters {{ and }}
for {
item := l.nextItem()
items = append(items, item)
if item.typ == itemEOF || item.typ == itemError {
break
}
}
return
The key parts of the source code are below:
// itemType identifies the type of lex items.
type itemType int
const (
itemError itemType = iota // error occurred; value is text of error
itemEOF
itemLeftDelim // left action delimiter
// .............. skipped
)
const (
leftDelim = "{{"
rightDelim = "}}"
leftComment = "/*"
rightComment = "*/"
)
// item represents a token or text string returned from the scanner.
type item struct {
typ itemType // The type of this item.
pos Pos // The starting position, in bytes, of this item in the input string.
val string // The value of this item.
}
// stateFn represents the state of the scanner as a function that returns the next state.
type stateFn func(*lexer) stateFn
// lexer holds the state of the scanner.
type lexer struct {
name string // the name of the input; used only for error reports
input string // the string being scanned
leftDelim string // start of action
rightDelim string // end of action
state stateFn // the next lexing function to enter
pos Pos // current position in the input
start Pos // start position of this item
width Pos // width of last rune read from input
lastPos Pos // position of most recent item returned by nextItem
items chan item // channel of scanned items
parenDepth int // nesting depth of ( ) exprs
}
// lex creates a new scanner for the input string.
func lex(name, input, left, right string) *lexer {
if left == "" {
left = leftDelim
}
if right == "" {
right = rightDelim
}
l := &lexer{
name: name,
input: input,
leftDelim: left,
rightDelim: right,
items: make(chan item),
}
go l.run()
return l
}
// run runs the state machine for the lexer.
func (l *lexer) run() {
for l.state = lexText; l.state != nil; {
l.state = l.state(l)
}
}
// nextItem returns the next item from the input.
func (l *lexer) nextItem() item {
item := <-l.items
l.lastPos = item.pos
return item
}
// emit passes an item back to the client.
func (l *lexer) emit(t itemType) {
l.items <- item{t, l.start, l.input[l.start:l.pos]}
l.start = l.pos
}
// lexText scans until an opening action delimiter, "{{".
func lexText(l *lexer) stateFn {
for {
if strings.HasPrefix(l.input[l.pos:], l.leftDelim) {
if l.pos > l.start {
l.emit(itemText)
}
return lexLeftDelim
}
if l.next() == eof {
break
}
}
// Correctly reached EOF.
if l.pos > l.start {
l.emit(itemText)
}
l.emit(itemEOF)
return nil
}
// next returns the next rune in the input.
func (l *lexer) next() rune {
if int(l.pos) >= len(l.input) {
l.width = 0
return eof
}
r, w := utf8.DecodeRuneInString(l.input[l.pos:])
l.width = Pos(w)
l.pos += l.width
return r
}
// lexLeftDelim scans the left delimiter, which is known to be present.
func lexLeftDelim(l *lexer) stateFn {
l.pos += Pos(len(l.leftDelim))
if strings.HasPrefix(l.input[l.pos:], leftComment) {
return lexComment
}
l.emit(itemLeftDelim)
l.parenDepth = 0
return lexInsideAction
}
// lexRightDelim scans the right delimiter, which is known to be present.
func lexRightDelim(l *lexer) stateFn {
l.pos += Pos(len(l.rightDelim))
l.emit(itemRightDelim)
return lexText
}
// there are more stateFn
So I was able to write the item and itemType:
case class Item(typ: ItemType, pos: Int, v: String)
sealed trait ItemType
case object ItemError extends ItemType
case object ItemEOF extends ItemType
case object ItemLeftDelim extends ItemType
...
..
.
The stateFn and Lex definitions:
trait StateFn extends (Lexer => StateFn) {
}
I'm basically really stuck on the main parts here. So things seem to be kicked of like this:
A Lex is created, then "go l.run()" is called.
Run is a loop, which keeps looping until EOF or an error is found.
The loop initializes with lexText, which scans until it finds an {{, and then it sends a message to a channel with all the preceding text of type 'itemText', passing it an 'item'. It then returns the function lexLeftDelim. lexLeftDelim does the same sort of thing, it sends a message 'item' of type itemLeftDelim.
It keeps parsing the string until it reaches EOF basically.
I can't think in scala that well, but I know I can use an Actor here to pass it a message 'Item'.
The part of returning a function, I asked I got some good ideas here: How to model recursive function types?
Even after this, I am really frustrated and I can seem to glue these concepts together.
I'm not looking for someone to implement the entire thing for me, but if someone could write just enough code to parse a simple string like "{{}}" that would be awesome. And if they could explain why they did a certain design that would be great.
I created a case class for Lex:
case class Lex(
name: String,
input: String,
leftDelim: String,
rightDelim: String,
state: StateFn,
var pos: Int = 0,
var start: Int = 0,
var width: Int = 0,
var lastPos: Int = 0,
var parenDepth: Int = 0
) {
def next(): Option[String] = {
if (this.pos >= this.input.length) {
this.width = 0
return None
}
this.width = 1
val nextChar = this.input.drop(this.pos).take(1)
this.pos += 1
Some(nextChar)
}
}
The first stateFn is LexText and so far I have:
object LexText extends StateFn {
def apply(l: Lexer) = {
while {
if (l.input.startsWith(l.leftDelim)) {
if (l.pos > l.start) {
// ????????? emit itemText using an actor?
}
return LexLeftDelim
}
if (l.next() == None) {
break
}
}
if(l.pos > l.start) {
// emit itemText
}
// emit EOF
return None // ?? nil? how can I support an Option[StateFn]
}
}
I need guidance on getting the Actor's setup, along with the main run loop:
func (l *lexer) run() {
for l.state = lexText; l.state != nil; {
l.state = l.state(l)
}
}
This is an interesting problem domain that I tried to tackle using Scala, and so far I am a bit confused hoping some else finds it interesting and can work with what little I have so far and provide some code and critique if I am doing it correctly or not.
I know deep down I shouldn't be mutating, but I'm still on the first few pages of the functional book :)
If you translate the go code literally into Scala, you'll get very unidiomatic piece of code. You'll probably get much more maintainable (and shorter!) Scala version by using parser combinators. There are plenty of resources about them on the internet.
import scala.util.parsing.combinator._
sealed trait ItemType
case object LeftDelim extends ItemType
case object RightDelim extends ItemType
case object Identifier extends ItemType
case class Item(ty: ItemType, token: String)
object ItemParser extends RegexParsers {
def left: Parser[Item] = """\{\{""".r ^^ { _ => Item(LeftDelim, "{{") }
def right: Parser[Item] = """\}\}""".r ^^ { _ => Item(RightDelim, "}}") }
def ident: Parser[Item] = """[a-z]+""".r ^^ { x => Item(Identifier, x) }
def item: Parser[Item] = left | right | ident
def items: Parser[List[Item]] = rep(item)
}
// ItemParser.parse(ItemParser.items, "{{foo}}")
// res5: ItemParser.ParseResult[List[Item]] =
// [1.8] parsed: List(Item(LeftDelim,{{), Item(Identifier,foo), Item(RightDelim,}}))
Adding whitespace skipping, or configurable left and right delimiters is trivial.
I'm following a tutorial on how to validate form fields, but it only demonstrates it for one field. How can I validate, and display errors for multiple fields?
I tried the following - but it always succeeds and does a redirect - no matter the errors:
def process() = {
if (patientName == "Joe") {
S.error("patientName", "Joe not allowed!")
}
if (birthdate == "22/22/2222") {
S.error("birthdate", "Invalid date!")
}
S.notice("Success! You entered Patient name: " + patientName); S.redirectTo("/")
}
Ha! I figured it out. Beautiful.
def process() = {
if (patientName == "Joe") {
S.error("Joe not allowed!")
}
if (birthdate == "22/22/2222") {
S.error("birthdate", "Invalid birthdate!")
}
S.errors match {
case Nil =>S.notice("Patient name: " + patientName); S.redirectTo("/")
case _ =>
}
}