Options parser improvement

src/app/cli_cmd.cpp

@@ -120,22 +120,22 @@ static std::optional<opt::OptionsResult> ParseCliCommandCommon(OrderedMap<std::s
 
 static opt::OptionsDescription DefaultDesc(const std::string &subCommand, const CmdEntry &entry)
 {
-    return {{}, {}, entry.descriptionText, {}, subCommand, {entry.usageText}, entry.helpIfEmpty, true};
+    return {{}, {}, entry.descriptionText, {}, subCommand, {entry.usageText}, {}, entry.helpIfEmpty, true};
 }
 
 static opt::OptionsDescription DescForPsEstablish(const std::string &subCommand, const CmdEntry &entry)
 {
-    std::string usage1 = "<session-type> [options]";
-    std::string usage2 = "IPv4 --sst 1 --sd 1 --dnn internet";
-    std::string usage3 = "IPv4 --emergency";
+    std::string example1 = "IPv4 --sst 1 --sd 1 --dnn internet";
+    std::string example2 = "IPv4 --emergency";
 
     auto res = opt::OptionsDescription{
-        {}, {}, entry.descriptionText, {}, subCommand, {usage1, usage2, usage3}, entry.helpIfEmpty, true};
+        {},  {}, entry.descriptionText, {}, subCommand, {entry.usageText}, {example1, example2}, entry.helpIfEmpty,
+        true};
 
-    res.items.emplace_back(std::nullopt, "sst", "SST value of the PDU session (Optional)", "value");
-    res.items.emplace_back(std::nullopt, "sd", "SD value of the PDU session (Optional)", "value");
-    res.items.emplace_back('n', "dnn", "DNN/APN value of the PDU session (Optional)", "apn");
-    res.items.emplace_back('e', "emergency", "Request as an emergency session (Optional)", std::nullopt);
+    res.items.emplace_back(std::nullopt, "sst", "SST value of the PDU session", "value");
+    res.items.emplace_back(std::nullopt, "sd", "SD value of the PDU session", "value");
+    res.items.emplace_back('n', "dnn", "DNN/APN value of the PDU session", "apn");
+    res.items.emplace_back('e', "emergency", "Request as an emergency session", std::nullopt);
 
     return res;
 }
@@ -158,7 +158,8 @@ static OrderedMap<std::string, CmdEntry> g_ueCmdEntries = {
     {"timers", {"Dump current status of the timers in the UE", "", DefaultDesc, false}},
     {"deregister",
      {"Perform a de-registration by the UE", "<normal|disable-5g|switch-off|remove-sim>", DefaultDesc, true}},
-    {"ps-establish", {"Trigger a PDU session establishment procedure", "", DescForPsEstablish, true}},
+    {"ps-establish",
+     {"Trigger a PDU session establishment procedure", "<session-type> [options]", DescForPsEstablish, true}},
     {"ps-release", {"Trigger a PDU session release procedure", "<pdu-session-id>...", DefaultDesc, true}},
     {"ps-release-all", {"Trigger PDU session release procedures for all active sessions", "", DefaultDesc, false}},
 };

src/cli.cpp

@@ -134,7 +134,7 @@ static void ReadOptions(int argc, char **argv)
 {
     opt::OptionsDescription desc{"UERANSIM",  cons::Tag, "Command Line Interface",
                                  cons::Owner, "nr-cli",  {"<node-name> [option...]", "--dump"},
-                                 true,        false};
+                                 {},          true,      false};
 
     opt::OptionItem itemDump = {'d', "dump", "List all UE and gNBs in the environment", std::nullopt};
     opt::OptionItem itemExec = {'e', "exec", "Execute the given command directly without an interactive shell",

src/gnb.cpp

@@ -78,9 +78,15 @@ static nr::gnb::GnbConfig *ReadConfigYaml()
 
 static void ReadOptions(int argc, char **argv)
 {
-    opt::OptionsDescription desc{cons::Project, cons::Tag, "5G-SA gNB implementation",
-                                 cons::Owner,   "nr-gnb",  {"-c <config-file> [option...]"},
-                                 true,          false};
+    opt::OptionsDescription desc{cons::Project,
+                                 cons::Tag,
+                                 "5G-SA gNB implementation",
+                                 cons::Owner,
+                                 "nr-gnb",
+                                 {"-c <config-file> [option...]"},
+                                 {},
+                                 true,
+                                 false};
 
     opt::OptionItem itemConfigFile = {'c', "config", "Use specified configuration file for gNB", "config-file"};
     opt::OptionItem itemDisableCmd = {'l', "disable-cmd", "Disable command line functionality for this instance",

src/ue.cpp

@@ -220,9 +220,9 @@ static nr::ue::UeConfig *ReadConfigYaml()
 
 static void ReadOptions(int argc, char **argv)
 {
-    opt::OptionsDescription desc{cons::Project, cons::Tag, "5G-SA UE implementation",
-                                 cons::Owner,   "nr-ue",   {"-c <config-file> [option...]"},
-                                 true,          false};
+    opt::OptionsDescription desc{
+        cons::Project, cons::Tag, "5G-SA UE implementation", cons::Owner, "nr-ue", {"-c <config-file> [option...]"}, {},
+        true,          false};
 
     opt::OptionItem itemConfigFile = {'c', "config", "Use specified configuration file for UE", "config-file"};
     opt::OptionItem itemImsi = {'i', "imsi", "Use specified IMSI number instead of provided one", "imsi"};

src/utils/options.cpp

@@ -264,10 +264,21 @@ void opt::OptionsResult::showHelp() const
 
     ostream << std::endl;
 
-    ostream << "Usage:" << std::endl;
-    for (auto &usage : m_description.usages)
-        ostream << "  " << m_description.programName << " " << usage << std::endl;
-    ostream << std::endl;
+    if (!m_description.usages.empty())
+    {
+        ostream << "Usage:" << std::endl;
+        for (auto &usage : m_description.usages)
+            ostream << "  " << m_description.programName << " " << usage << std::endl;
+        ostream << std::endl;
+    }
+
+    if (!m_description.examples.empty())
+    {
+        ostream << (m_description.examples.size() > 1 ? "Examples:" : "Example:") << std::endl;
+        for (auto &example : m_description.examples)
+            ostream << "  " << m_description.programName << " " << example << std::endl;
+        ostream << std::endl;
+    }
 
     std::vector<OptionItem> items = m_description.items;
     if (!m_description.hideDefaultOptionsInUsage)

src/utils/options.hpp

@@ -72,15 +72,16 @@ struct OptionsDescription
     std::string programName{};
     std::vector<OptionItem> items{};
     std::vector<std::string> usages{};
+    std::vector<std::string> examples{};
     bool helpIfEmpty{};
     bool hideDefaultOptionsInUsage{};
 
     OptionsDescription(std::string projectName, std::string version, std::string appDescription, std::string copyright,
-                       std::string programName, std::vector<std::string> usages, bool helpIfEmpty,
-                       bool hideDefaultOptionsInUsage)
+                       std::string programName, std::vector<std::string> usages, std::vector<std::string> examples,
+                       bool helpIfEmpty, bool hideDefaultOptionsInUsage)
         : projectName(std::move(projectName)), version(std::move(version)), appDescription(std::move(appDescription)),
           copyright(std::move(copyright)), programName(std::move(programName)), usages(std::move(usages)),
-          helpIfEmpty(helpIfEmpty), hideDefaultOptionsInUsage(hideDefaultOptionsInUsage)
+          examples(std::move(examples)), helpIfEmpty(helpIfEmpty), hideDefaultOptionsInUsage(hideDefaultOptionsInUsage)
     {
     }
 };