bmcweb: /s/boost::string_view/std::string_view/g

With boost 1.69, we get the new option, BOOST_BEAST_USE_STD_STRING_VIEW
which allows us to use std::string for all beast interfaces, instead of
boost string_view.  This was originally intended to try to reduce the
binary size, but the comparison shows only a minor improvement.

boost::string_view: 7420780 bytes
std::string_view:   7419948 bytes

832 bytes saved ! ! ! ! !

So instead, we will use the argument that it's more standard and easier
for people to grok.

Tested By:
Pulled down some bmcweb endpoints, and observed no change.  Because the
two objects are essentially drop in replacements for one another, there
should be no change.

Change-Id: I001e8cf2a0124de4792a7154bf246e3c35ef3f97
Signed-off-by: Ed Tanous <ed.tanous@intel.com>
diff --git a/include/http_utility.hpp b/include/http_utility.hpp
index 0f5bb8c..e2b1a11 100644
--- a/include/http_utility.hpp
+++ b/include/http_utility.hpp
@@ -5,7 +5,7 @@
 {
 inline bool requestPrefersHtml(const crow::Request& req)
 {
-    boost::string_view header = req.getHeaderValue("accept");
+    std::string_view header = req.getHeaderValue("accept");
     std::vector<std::string> encodings;
     // chrome currently sends 6 accepts headers, firefox sends 4.
     encodings.reserve(6);
@@ -25,7 +25,7 @@
     return false;
 }
 
-inline std::string urlEncode(const boost::string_view value)
+inline std::string urlEncode(const std::string_view value)
 {
     std::ostringstream escaped;
     escaped.fill('0');
diff --git a/include/pam_authenticate.hpp b/include/pam_authenticate.hpp
index 7f2a33c..f211a29 100644
--- a/include/pam_authenticate.hpp
+++ b/include/pam_authenticate.hpp
@@ -17,7 +17,7 @@
     char* appPass = reinterpret_cast<char*>(appdataPtr);
     size_t appPassSize = std::strlen(appPass);
     char* pass = reinterpret_cast<char*>(malloc(appPassSize + 1));
-    if (!pass)
+    if (pass == nullptr)
     {
         return PAM_AUTH_ERR;
     }
@@ -27,7 +27,7 @@
     *resp = reinterpret_cast<pam_response*>(
         calloc(numMsg, sizeof(struct pam_response)));
 
-    if (resp == NULL)
+    if (resp == nullptr)
     {
         return PAM_AUTH_ERR;
     }
@@ -47,8 +47,8 @@
     return PAM_SUCCESS;
 }
 
-inline bool pamAuthenticateUser(const boost::string_view username,
-                                const boost::string_view password)
+inline bool pamAuthenticateUser(const std::string_view username,
+                                const std::string_view password)
 {
     std::string userStr(username);
     std::string passStr(password);
diff --git a/include/sessions.hpp b/include/sessions.hpp
index 510f566..6bc1c99 100644
--- a/include/sessions.hpp
+++ b/include/sessions.hpp
@@ -102,7 +102,7 @@
 {
   public:
     std::shared_ptr<UserSession> generateUserSession(
-        const boost::string_view username,
+        const std::string_view username,
         PersistenceType persistence = PersistenceType::TIMEOUT)
     {
         // TODO(ed) find a secure way to not generate session identifiers if
@@ -148,7 +148,7 @@
     }
 
     std::shared_ptr<UserSession>
-        loginSessionByToken(const boost::string_view token)
+        loginSessionByToken(const std::string_view token)
     {
         applySessionTimeouts();
         auto sessionIt = authTokens.find(std::string(token));
@@ -161,7 +161,7 @@
         return userSession;
     }
 
-    std::shared_ptr<UserSession> getSessionByUid(const boost::string_view uid)
+    std::shared_ptr<UserSession> getSessionByUid(const std::string_view uid)
     {
         applySessionTimeouts();
         // TODO(Ed) this is inefficient
diff --git a/include/token_authorization_middleware.hpp b/include/token_authorization_middleware.hpp
index b186a5f..c5c6523 100644
--- a/include/token_authorization_middleware.hpp
+++ b/include/token_authorization_middleware.hpp
@@ -39,7 +39,7 @@
         }
         if (ctx.session == nullptr)
         {
-            boost::string_view authHeader = req.getHeaderValue("Authorization");
+            std::string_view authHeader = req.getHeaderValue("Authorization");
             if (!authHeader.empty())
             {
                 // Reject any kind of auth other than basic or token
@@ -104,12 +104,12 @@
 
   private:
     const std::shared_ptr<crow::persistent_data::UserSession>
-        performBasicAuth(boost::string_view auth_header) const
+        performBasicAuth(std::string_view auth_header) const
     {
         BMCWEB_LOG_DEBUG << "[AuthMiddleware] Basic authentication";
 
         std::string authData;
-        boost::string_view param = auth_header.substr(strlen("Basic "));
+        std::string_view param = auth_header.substr(strlen("Basic "));
         if (!crow::utility::base64Decode(param, authData))
         {
             return nullptr;
@@ -146,11 +146,11 @@
     }
 
     const std::shared_ptr<crow::persistent_data::UserSession>
-        performTokenAuth(boost::string_view auth_header) const
+        performTokenAuth(std::string_view auth_header) const
     {
         BMCWEB_LOG_DEBUG << "[AuthMiddleware] Token authentication";
 
-        boost::string_view token = auth_header.substr(strlen("Token "));
+        std::string_view token = auth_header.substr(strlen("Token "));
         auto session =
             persistent_data::SessionStore::getInstance().loginSessionByToken(
                 token);
@@ -162,7 +162,7 @@
     {
         BMCWEB_LOG_DEBUG << "[AuthMiddleware] X-Auth-Token authentication";
 
-        boost::string_view token = req.getHeaderValue("X-Auth-Token");
+        std::string_view token = req.getHeaderValue("X-Auth-Token");
         if (token.empty())
         {
             return nullptr;
@@ -178,7 +178,7 @@
     {
         BMCWEB_LOG_DEBUG << "[AuthMiddleware] Cookie authentication";
 
-        boost::string_view cookieValue = req.getHeaderValue("Cookie");
+        std::string_view cookieValue = req.getHeaderValue("Cookie");
         if (cookieValue.empty())
         {
             return nullptr;
@@ -195,7 +195,7 @@
         {
             endIndex = cookieValue.size();
         }
-        boost::string_view authKey =
+        std::string_view authKey =
             cookieValue.substr(startIndex, endIndex - startIndex);
 
         const std::shared_ptr<crow::persistent_data::UserSession> session =
@@ -209,7 +209,7 @@
         // RFC7231 defines methods that need csrf protection
         if (req.method() != "GET"_method)
         {
-            boost::string_view csrf = req.getHeaderValue("X-XSRF-TOKEN");
+            std::string_view csrf = req.getHeaderValue("X-XSRF-TOKEN");
             // Make sure both tokens are filled
             if (csrf.empty() || session->csrfToken.empty())
             {
@@ -274,9 +274,9 @@
     BMCWEB_ROUTE(app, "/login")
         .methods(
             "POST"_method)([&](const crow::Request& req, crow::Response& res) {
-            boost::string_view contentType = req.getHeaderValue("content-type");
-            boost::string_view username;
-            boost::string_view password;
+            std::string_view contentType = req.getHeaderValue("content-type");
+            std::string_view username;
+            std::string_view password;
 
             bool looksLikeIbm = false;