I have an internal function
function _somefunction() internal {
if (address(attr) != address(0)) {
try attr.maybedoesntexist() {
} catch Error(string memory message) {
emit SomethingFailed();
} catch {
emit SomethingFailed();
}
}
}
When I test this in hardhat I set attr to be a non-contract, but somehow the error function call to a non-contract account goes through the first catch and the whole thing reverts.
No other function uses attr and the error is completely dependent on whether attr is a contract account. Can catch actually not handle some errors?
Exceptions from calls to non-contracts are currently (v0.8) not caught by try/catch.
You can validate whether the address is a contract, and only invoke calls on contracts:
// length of attr's bytecode is 0, it's not a contract
if (address(attr).code.length == 0) {
return;
}
try attr.maybedoesntexist() {
Related
How to call run-local (without sending a message) function of another contract from debot? For example, for getting a public variable.
This was useful for me.
In debot:
Create interface for function of another contract with function (if public variable too).
interface IOther {
function funcName()
external returns(uint);
}
Build the message and send it.
function runLocal() public{
optional(uint256) pubkey = 0;
address remoteContract = address.makeAddrStd(0, 0xceaa3bc6b00cf2b1e750dae2dd94d246a126a989009a3fb3bb73bea1a48b3b);
TvmCell message = tvm.buildExtMsg({
abiVer: 2,
callbackId: tvm.functionId(onSuccessFuncName),
onErrorId: tvm.functionId(onErrorFuncName),
time: uint64(now),
dest: remoteContract,
call: {
IOther.funcName
}
});
tvm.sendrawmsg(message, 1);
}
function onSuccessFuncName(uint response) public{
/* working with response from remote contract */
}
function onErrorFuncName() public{
/* catch error */
}
I need to verify that a certain call is not made, when a previous method call throws an Exception.
// GIVEN
every { relaxedMock.eats() }.throws(NotHungryException())
// WHEN
sut.live()
// THEN
verify (exactly = 0) { relaxedMock2.sleeps() }
Problem with this code, it fails because of the Exception thrown and not because of the failed verification.
I understand that your WHEN block will always throw an exception.
In that case you have multiple options from my point of view:
Simple plain Kotlin. Wrap the WHEN block with a try-catch block, e.g. like this:
// GIVEN
every { relaxedMock.eats() }.throws(NotHungryException())
// WHEN
var exceptionThrown: Boolean = false
try {
sut.live()
} catch(exception: NotHungryException) {
// Maybe put some assertions on the exception here.
exceptionThrown = true
}
assertTrue(exceptionThrown)
// THEN
verify (exactly = 0) { relaxedMock2.sleeps() }
For a bit nicer code, you can use JUnit5 API's Assertions. assertThrows will expect an exception being thrown by a specific piece of code. It will fail the test, if no exception is thrown. Also it will return the thrown exception, for you to inspect it.
import org.junit.jupiter.api.Assertions
// GIVEN
every { relaxedMock.eats() }.throws(NotHungryException())
// WHEN
val exception = Assertions.assertThrows(NotHungryException::class.java) { sut.live() }
// THEN
verify (exactly = 0) { relaxedMock2.sleeps() }
If you're using Kotest you can use the shouldThrow assertion. Which also allows you to retrieve the thrown exception and validate its type.
import io.kotest.assertions.throwables.shouldThrow
// GIVEN
every { relaxedMock.eats() }.throws(NotHungryException())
// WHEN
val exception = shouldThrow<NotHungryException> { sut.live() }
// THEN
verify (exactly = 0) { relaxedMock2.sleeps() }
I had similar issue and found that my method is not surrounded by try catch. This mean the method will always throw exception.
Test
The unit test to verify the result when the following method is called while stubbing it with predefine Exception
#Test
fun returnSearchError() {
every { searchService.search(query) }.throws(BadSearchException())
val result = searchRepository.search(query)
assertEquals(SearchStates.SearchError, result)
}
Faulty code
fun search(query: String): SearchStates {
val result = searchService.search(query) // No try catch for the thrown exception
return try {
SearchStates.MatchingResult(result)
} catch (badSearchException: BadSearchException) {
SearchStates.SearchError
}
}
Refactored it to
fun search(query: String): SearchStates {
return try {
val result = searchService.search(query)
SearchStates.MatchingResult(result)
} catch (badSearchException: BadSearchException) {
SearchStates.SearchError
}
}
I'm probably overlooking something simple, but I do not expect the below code to fail. It is behaving as if I wrote die instead of fail in the catch block.
The Failure does not get properly handled and the code dies.
sub foo()
{
try {
say 1 / 0;
CATCH { default { fail "FAIL" } }
}
return True;
}
with foo() {
say "done";
}
else
{
say "handled {.exception.message}"
}
Output:
FAIL
in block at d:\tmp\x.pl line 5
in any at d:\tmp\x.pl line 5
in sub foo at d:\tmp\x.pl line 4
in block <unit> at d:\tmp\x.pl line 11
To bring home to later readers the full force of what Yoda said in their comment, the simplest solution is to unlearn the notion that you have to try in order to CATCH. You don't:
sub foo()
{
say 1 / 0;
CATCH { default { fail "FAIL" } }
return True;
}
with foo() {
say "done";
}
else
{
say "handled {.exception.message}"
}
correctly displays:
handled FAIL
According to the Failure documentation this seems to be the defined behavior.
Sink (void) context causes a Failure to throw, i.e. turn into a normal exception. The use fatal pragma causes this to happen in all contexts within the pragma's scope. Inside try blocks, use fatal is automatically set, and you can disable it with no fatal.
You can try to use the no fatal pragma.
sub foo() {
try {
no fatal;
say 1 / 0;
CATCH { default { fail "FAIL" } }
}
}
unless foo() {
say "handled"
}
I have written a common validator as part of Ninject interceptor. My requirement is that I have to return a response object, just like how any service method in my project returns, for consistency sake. By returning a response object also helps me to send back an appropriate validation message when the validator fails. How do I do that in the interceptor? I understood that the Intercept() returns nothing. I tried throwing an exception but I don't know where to catch it. Can someone help me?
public void Intercept(IInvocation invocation)
{
var validationFails = false;
if (validationFails)
{
// return an object
// response.ErrorMessage = "Validation Error"
// Or throw exception, but where should I catch it
throw new Exception(statusMessage);
}
else
{
invocation.Proceed();
}
}
Assign the ReturnValue and don't call Proceed when validation fails.
public class MyRequestHandler
{
Response ProcessRequest(string input) { return new Response(); }
}
public MyValidationInterceptor : IInterceptor
{
public void Intercept( IInvocation invocation )
{
if (NeedsValidation(invocation.Method) &&
!IsValidRequest((string)invocation.Arguments[0]))
{
invocation.ReturnValue =
new Response { ErrorMessage = "Validation Error" };
return;
}
invocation.Proceed();
}
}
I had to hook up my interceptor to business layer methods, instead of service methods, and am able to return proper return value as part of my response.
I'm implementing a custom Authentication Handler for wso2-am following this guide https://docs.wso2.com/display/AM190/Writing+Custom+Handlers
But it's not clear how to handle the case when my authentication handler returns false. The sample code of the handleRequest is
public boolean handleRequest(MessageContext messageContext) {
try {
if (authenticate(messageContext)) {
return true;
}
} catch (APISecurityException e) {
e.printStackTrace();
}
return false;
}
If I try calling an API with valid credentials everything goes well (the method returns true) and I get an "HTTP 200 OK" response. If I try with invalid credentials the method returns false but I get an HTTP 202 ACCEPTED" response. I would like to receive another response code (for example 400). How do I handle this authentication failure path?
Thank you.
Ideally you need to call handleAuthFaliure method with message context.
private void handleAuthFailure(MessageContext messageContext, APISecurityException e)
When you call that method please create APISecurityException object(as listed below) and pass it. Then error code and error messages will be picked from there and automatically send error to client(by default we return 401 for security exceptions and if defined then send defined error code and message).
public class APISecurityException extends Exception {
private int errorCode;
public APISecurityException(int errorCode, String message) {
super(message);
this.errorCode = errorCode;
}
public APISecurityException(int errorCode, String message, Throwable cause) {
super(message, cause);
this.errorCode = errorCode;
}
public int getErrorCode() {
return errorCode;
}
}
Hope this will work for you.
Thanks
sanjeewa.