[C++] Fix wrong unit of Access Token Response's expires_in field (a…

…pache#14554)

### Motivation

The `expires_in` field of Access Token Response is in seconds. See
https://datatracker.ietf.org/doc/html/rfc6749#section-4.2.2. However,
C++ client treats it as milliseconds currently. It will leads to an
earlier expiration of the token.

### Modifications

Record the time point via the `std::time_point` class, which supports
add operations with a `std::duration` object. Then converts the
`expires_in` field via `std::chrono::second` function and calculate the
expired time point.

It also removes the usage of Boost time functions and makes code more clear.

(cherry picked from commit 95c1581)
(cherry picked from commit 669ce98)

pulsar-client-cpp/lib/auth/AuthOauth2.cc

@@ -23,7 +23,6 @@
 #include <stdexcept>
 #include <boost/property_tree/json_parser.hpp>
 #include <boost/property_tree/ptree.hpp>
-#include <boost/date_time/posix_time/posix_time.hpp>
 
 #include <lib/LogUtils.h>
 DECLARE_LOG_OBJECT()
@@ -86,22 +85,12 @@ CachedToken::~CachedToken() {}
 
 // Oauth2CachedToken
 
-static int64_t currentTimeMillis() {
-    using namespace boost::posix_time;
-    using boost::posix_time::milliseconds;
-    using boost::posix_time::seconds;
-    static ptime time_t_epoch(boost::gregorian::date(1970, 1, 1));
-
-    time_duration diff = microsec_clock::universal_time() - time_t_epoch;
-    return diff.total_milliseconds();
-}
-
 Oauth2CachedToken::Oauth2CachedToken(Oauth2TokenResultPtr token) {
     latest_ = token;
 
     int64_t expiredIn = token->getExpiresIn();
     if (expiredIn > 0) {
-        expiresAt_ = expiredIn + currentTimeMillis();
+        expiresAt_ = Clock::now() + std::chrono::seconds(expiredIn);
     } else {
         throw std::runtime_error("ExpiresIn in Oauth2TokenResult invalid value: " +
                                  std::to_string(expiredIn));
@@ -113,7 +102,7 @@ AuthenticationDataPtr Oauth2CachedToken::getAuthData() { return authData_; }
 
 Oauth2CachedToken::~Oauth2CachedToken() {}
 
-bool Oauth2CachedToken::isExpired() { return expiresAt_ < currentTimeMillis(); }
+bool Oauth2CachedToken::isExpired() { return expiresAt_ < Clock::now(); }
 
 // OauthFlow
 

pulsar-client-cpp/lib/auth/AuthOauth2.h

@@ -20,6 +20,7 @@
 #pragma once
 
 #include <pulsar/Authentication.h>
+#include <chrono>
 #include <mutex>
 #include <string>
 
@@ -69,13 +70,15 @@ class ClientCredentialFlow : public Oauth2Flow {
 
 class Oauth2CachedToken : public CachedToken {
    public:
+    using Clock = std::chrono::high_resolution_clock;
+
     Oauth2CachedToken(Oauth2TokenResultPtr token);
     ~Oauth2CachedToken();
     bool isExpired();
     AuthenticationDataPtr getAuthData();
 
    private:
-    int64_t expiresAt_;
+    std::chrono::time_point<Clock> expiresAt_;
     Oauth2TokenResultPtr latest_;
     AuthenticationDataPtr authData_;
 };