Fix segmentation fault when use token auth

[shibd]

Motivation

#395 Introduce a regression on node:20-alpine env. if use a token to connect to pulsar, will get a segmentation fault when client closes.

[INFO][ClientConnection:282] [10.88.0.2:51556 -> 34.28.200.175:6651] Destroyed connection to **** [INFO][ClientConnection:282] [10.88.0.2:51544 -> 34.28.200.175:6651] Destroyed connection to **** Bus error (core dumped) 

Happend here:

pulsar-client-node/src/Authentication.cc

Lines 181 to 183 in c52bd1b

	if (this->tokenSupplier != nullptr) {
	this->tokenSupplier->callback.Release();
	}

Modifications

• We need to explicitly set tokenSupplier to nullptr, as uninitialized pointers in C++ have undefined default values.

Verifying this change

• Verified on my local test.

Documentation

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[klaatu01]

I randomly get a segmentation fault on startup when using 1.13.0 with promise-based tokenSupplier. Is this related?

[shibd]

I randomly get a segmentation fault on startup when using 1.13.0 with promise-based tokenSupplier. Is this related?

@klaatu01 I think so. Could you help verify if the issue still exists in version v1.13.1? You can use the following cmd to install it:

npm i pulsar-client@1.13.1-rc.1 --pulsar_binary_host_mirror=https://dist.apache.org/repos/dist/dev/pulsar/pulsar-client-node/ 

[doug8679]

@shibd what is the testing / release process and timing for an update to this in npm? We had this issue crop up in on of our services under active development and we have had to lock our pulsar-client version at 1.12.0 until a fix is available. I tried testing the RC.1 package locally but have not been successful getting that package installed in a Docker image for a full test of the situation we ran into.

[shibd]

@doug8679 The v1.13.1 has been released, you can try it.