[fix][auth] Generate correct well-known OpenID configuration URL

[gaoran10]

Motivation

Currently, the well-known OpenID configuration URL generated by issuer_url and suffix (/.well-known/openid-configuration), if the issurer_url end with a slash, the well-known OpenID configuration URL will be not correct.

Demo

issuer_url: https://dev-kt-aa9ne.us.auth0.com/
openid_url: https://dev-kt-aa9ne.us.auth0.com//.well-known/openid-configuration

Making the issuer_url as below could work well.

issuer_url: https://dev-kt-aa9ne.us.auth0.com/
issuer_url: https://dev-kt-aa9ne.us.auth0.com

Modifications

Trim the slash if the issuer_url end with a slash.

Verifying this change

Add a unit test to verify the method ClientCredentialFlow::initialize.

Does this pull request potentially affect one of the following parts:

If yes was chosen, please highlight the changes

• Dependencies (does it add or upgrade a dependency): (no)
• The public API: (no)
• The schema: (no)
• The default values of configurations: (no)
• The wire protocol: (no)
• The rest endpoints: (no)
• The admin cli options: (no)
• Anything that affects deployment: (no)

Documentation

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[michaeljmarshall]

LTGM

[BewareMyPower]

In C++, returning a const object is meaningless. I think you want to make the method const to ensure the internal state doesn't change in the implementation.

[BewareMyPower]

Please apply the following patch to fix the code format.

diff --git a/pulsar-client-cpp/lib/auth/AuthOauth2.cc b/pulsar-client-cpp/lib/auth/AuthOauth2.cc
index 4bc5e8c814b2..c7f944da75b1 100644
--- a/pulsar-client-cpp/lib/auth/AuthOauth2.cc
+++ b/pulsar-client-cpp/lib/auth/AuthOauth2.cc
@@ -143,9 +143,7 @@ ClientCredentialFlow::ClientCredentialFlow(ParamMap& params)
       audience_(params["audience"]),
       scope_(params["scope"]) {}
 
-std::string ClientCredentialFlow::getTokenEndPoint() const {
-    return tokenEndPoint_;
-}
+std::string ClientCredentialFlow::getTokenEndPoint() const { return tokenEndPoint_; }
 
 static size_t curlWriteCallback(void* contents, size_t size, size_t nmemb, void* responseDataPtr) {
     ((std::string*)responseDataPtr)->append((char*)contents, size * nmemb);
@@ -177,7 +175,7 @@ void ClientCredentialFlow::initialize() {
         wellKnownUrl.pop_back();
     }
     wellKnownUrl.append("/.well-known/openid-configuration");
-    curl_easy_setopt(handle, CURLOPT_URL,wellKnownUrl.c_str());
+    curl_easy_setopt(handle, CURLOPT_URL, wellKnownUrl.c_str());
 
     // Write callback
     curl_easy_setopt(handle, CURLOPT_WRITEFUNCTION, curlWriteCallback);