Add environment variables to control daemon logging

src/scord-ctl/CMakeLists.txt

@@ -25,7 +25,7 @@
 # scord-ctl daemon
 add_executable(scord-ctl)
 
-target_sources(scord-ctl PRIVATE scord-ctl.cpp rpc_handlers.hpp rpc_handlers.cpp)
+target_sources(scord-ctl PRIVATE scord-ctl.cpp rpc_handlers.hpp rpc_handlers.cpp env.hpp)
 
 target_include_directories(
   scord-ctl

src/scord-ctl/env.hpp

+/******************************************************************************
+ * Copyright 2021-2022, Barcelona Supercomputing Center (BSC), Spain
+ *
+ * This software was partially supported by the EuroHPC-funded project ADMIRE
+ *   (Project ID: 956748, https://www.admire-eurohpc.eu).
+ *
+ * This file is part of scord.
+ *
+ * scord is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * scord is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with scord.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *****************************************************************************/
+
+#ifndef SCORD_CTL_ENV_HPP
+#define SCORD_CTL_ENV_HPP
+
+#define SCORD_ENV_PREFIX "SCORDCTL_"
+#define ADD_PREFIX(str)  SCORD_ENV_PREFIX str
+
+namespace scord_ctl::env {
+
+static constexpr auto LOG = ADD_PREFIX("LOG");
+static constexpr auto LOG_OUTPUT = ADD_PREFIX("LOG_OUTPUT");
+
+} // namespace scord_ctl::env
+
+
+#endif // SCORD_CTL_ENV_HPP

src/scord-ctl/scord-ctl.cpp

@@ -36,6 +36,7 @@
 #include <net/proto/rpc_types.h>
 #include <config/settings.hpp>
 #include "rpc_handlers.hpp"
+#include "env.hpp"
 
 namespace fs = std::filesystem;
 namespace bpo = boost::program_options;
@@ -52,6 +53,20 @@ print_help(const std::string& progname,
     fmt::print("{}", opt_desc);
 }
 
+std::unordered_map<std::string, std::string>
+load_envs() {
+
+    std::unordered_map<std::string, std::string> envs;
+
+    if(const auto p = std::getenv(scord_ctl::env::LOG);
+       p && !std::string{p}.empty() && std::string{p} != "0") {
+        if(const auto log_file = std::getenv(scord_ctl::env::LOG_OUTPUT)) {
+            envs.emplace(scord_ctl::env::LOG_OUTPUT, log_file);
+        }
+    }
+
+    return envs;
+}
 
 int
 main(int argc, char* argv[]) {
@@ -75,6 +90,7 @@ main(int argc, char* argv[]) {
                      ->implicit_value("")
                      ->zero_tokens()
                      ->notifier([&](const std::string&) {
+                         cfg.log_file(fs::path{});
                          cfg.use_console(true);
                      }),
              "override any logging options defined in configuration files and "
@@ -140,6 +156,15 @@ main(int argc, char* argv[]) {
             return EXIT_FAILURE;
         }
 
+        // override settings from the configuration file with settings
+        // from environment variables
+        const auto env_opts = load_envs();
+
+        if(const auto& it = env_opts.find(scord_ctl::env::LOG_OUTPUT);
+           it != env_opts.end()) {
+            cfg.log_file(it->second);
+        }
+
         // calling notify() here basically invokes all define notifiers, thus
         // overriding any configuration loaded from the global configuration
         // file with its command-line counterparts if provided (for those

src/scord/CMakeLists.txt

@@ -25,7 +25,7 @@
 # scord daemon
 add_executable(scord)
 
-target_sources(scord PRIVATE scord.cpp rpc_handlers.hpp rpc_handlers.cpp)
+target_sources(scord PRIVATE scord.cpp rpc_handlers.hpp rpc_handlers.cpp env.hpp)
 
 target_include_directories(
   scord

src/scord/env.hpp

+/******************************************************************************
+ * Copyright 2021-2022, Barcelona Supercomputing Center (BSC), Spain
+ *
+ * This software was partially supported by the EuroHPC-funded project ADMIRE
+ *   (Project ID: 956748, https://www.admire-eurohpc.eu).
+ *
+ * This file is part of scord.
+ *
+ * scord is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * scord is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with scord.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *****************************************************************************/
+
+#ifndef SCORD_ENV_HPP
+#define SCORD_ENV_HPP
+
+#define SCORD_ENV_PREFIX "SCORD_"
+#define ADD_PREFIX(str)  SCORD_ENV_PREFIX str
+
+namespace scord::env {
+
+static constexpr auto LOG = ADD_PREFIX("LOG");
+static constexpr auto LOG_OUTPUT = ADD_PREFIX("LOG_OUTPUT");
+
+} // namespace scord::env
+
+
+#endif // SCORD_ENV_HPP

src/scord/scord.cpp

@@ -36,6 +36,7 @@
 #include <net/proto/rpc_types.h>
 #include <config/settings.hpp>
 #include "rpc_handlers.hpp"
+#include "env.hpp"
 
 #include <agios.h>
 
@@ -54,6 +55,20 @@ print_help(const std::string& progname,
     fmt::print("{}", opt_desc);
 }
 
+std::unordered_map<std::string, std::string>
+load_envs() {
+
+    std::unordered_map<std::string, std::string> envs;
+
+    if(const auto p = std::getenv(scord::env::LOG);
+       p && !std::string{p}.empty() && std::string{p} != "0") {
+        if(const auto log_file = std::getenv(scord::env::LOG_OUTPUT)) {
+            envs.emplace(scord::env::LOG_OUTPUT, log_file);
+        }
+    }
+
+    return envs;
+}
 
 int
 main(int argc, char* argv[]) {
@@ -77,6 +92,7 @@ main(int argc, char* argv[]) {
                      ->implicit_value("")
                      ->zero_tokens()
                      ->notifier([&](const std::string&) {
+                         cfg.log_file(fs::path{});
                          cfg.use_console(true);
                      }),
              "override any logging options defined in configuration files and "
@@ -142,6 +158,15 @@ main(int argc, char* argv[]) {
             return EXIT_FAILURE;
         }
 
+        // override settings from the configuration file with settings
+        // from environment variables
+        const auto env_opts = load_envs();
+
+        if(const auto& it = env_opts.find(scord::env::LOG_OUTPUT);
+           it != env_opts.end()) {
+            cfg.log_file(it->second);
+        }
+
         // calling notify() here basically invokes all define notifiers, thus
         // overriding any configuration loaded from the global configuration
         // file with its command-line counterparts if provided (for those