Refactor of command line argument parsing to single file (#388)

Now command line parsing is broken down into a shared module so
it can be reused across samples. This makes samples smaller and
reduces bloat.

Commit log:
* Initial work on simplifying command line parsing
* Continued work on simplifying command line parsing
* Reformatted samples with, hopefully, the correct clang format setting this times
* Another attempt at fixing clang format issues
* Adjustments to CommandLineUtils and samples to allow building on Windows and Linux
* Adjusted secure_tunnel sample to use AWS String instead of std string
* Remove commented out namespace usage in secure_tunnel sample
* Adjusted samples command line parser to show input type for commands
* Minor command line parsing format fixes
* Adjusted based on review feedback
* Minor formatting fix
* Removed const in main function in samples
* Clang format fixes
* Added additional command groups
* Renamed AddCommonX509Commands utility function

Author: TwistedTwigleg

samples/greengrass/basic_discovery/CMakeLists.txt

@@ -4,6 +4,8 @@ project(basic-discovery CXX)
 
 file(GLOB SRC_FILES
        "*.cpp"
+       "../../utils/CommandLineUtils.cpp"
+       "../../utils/CommandLineUtils.h"
 )
 
 add_executable(${PROJECT_NAME} ${SRC_FILES})

samples/greengrass/basic_discovery/main.cpp

@@ -14,47 +14,11 @@
 #include <iostream>
 #include <mutex>
 
+#include "../../utils/CommandLineUtils.h"
+
 using namespace Aws::Crt;
 using namespace Aws::Discovery;
 
-static void s_printHelp()
-{
-    fprintf(stdout, "Usage:\n");
-    fprintf(
-        stdout,
-        "basic-discovery --region <optional: region> --cert <path to cert>"
-        " --key <path to key> --ca_file <optional: path to custom ca>"
-        " --thing_name <thing name> --topic <optional: topic> "
-        " --mode <optional: both|publish|subscribe> --message <optional: message to publish>"
-        " --proxy-host <optional: proxy host name> --proxy-port <optional: proxy port>\n\n");
-    fprintf(stdout, "region: the region for your green grass groups, default us-east-1\n");
-    fprintf(stdout, "cert: path to your client certificate in PEM format\n");
-    fprintf(stdout, "key: path to your key in PEM format\n");
-    fprintf(stdout, "ca_file: ca file to use in verifying TLS connections.\n");
-    fprintf(stdout, "\tIt's the path to a CA file in PEM format\n");
-    fprintf(stdout, "thing_name: the name of your IOT thing\n");
-    fprintf(stdout, "topic: targeted topic. Default is test/topic\n");
-    fprintf(stdout, "mode: default both\n");
-    fprintf(stdout, "message: message to publish. default 'Hello World'\n");
-    fprintf(stdout, "proxy-host: proxy host to use for discovery call. Default is to not use a proxy.\n");
-    fprintf(stdout, "proxy-port: proxy port to use for discovery call.\n");
-}
-
-bool s_cmdOptionExists(char **begin, char **end, const String &option)
-{
-    return std::find(begin, end, option) != end;
-}
-
-char *s_getCmdOption(char **begin, char **end, const String &option)
-{
-    char **itr = std::find(begin, end, option);
-    if (itr != end && ++itr != end)
-    {
-        return *itr;
-    }
-    return 0;
-}
-
 int main(int argc, char *argv[])
 {
     /************************ Setup the Lib ****************************/
@@ -75,50 +39,37 @@ int main(int argc, char *argv[])
     String message("Hello World");
 
     /*********************** Parse Arguments ***************************/
-    if (!(s_cmdOptionExists(argv, argv + argc, "--cert") && s_cmdOptionExists(argv, argv + argc, "--key") &&
-          s_cmdOptionExists(argv, argv + argc, "--thing_name")))
-    {
-        s_printHelp();
-        return 0;
-    }
-
-    certificatePath = s_getCmdOption(argv, argv + argc, "--cert");
-    keyPath = s_getCmdOption(argv, argv + argc, "--key");
-    thingName = s_getCmdOption(argv, argv + argc, "--thing_name");
-
-    if (s_cmdOptionExists(argv, argv + argc, "--ca_file"))
+    Utils::CommandLineUtils cmdUtils = Utils::CommandLineUtils();
+    cmdUtils.RegisterProgramName("basic-discovery");
+    cmdUtils.AddCommonMQTTCommands();
+    cmdUtils.AddCommonProxyCommands();
+    cmdUtils.AddCommonTopicMessageCommands();
+    cmdUtils.RemoveCommand("endpoint");
+    cmdUtils.RegisterCommand(
+        "region", "<str>", "The region for your Greengrass groups (optional, default='us-east-1').");
+    cmdUtils.RegisterCommand("thing_name", "<str>", "The name of your IOT thing");
+    cmdUtils.RegisterCommand(
+        "mode", "<str>", "Mode options: 'both', 'publish', or 'subscribe' (optional, default='both').");
+    const char **const_argv = (const char **)argv;
+    cmdUtils.SendArguments(const_argv, const_argv + argc);
+
+    if (cmdUtils.HasCommand("help"))
     {
-        caFile = s_getCmdOption(argv, argv + argc, "--ca_file");
-    }
-
-    if (s_cmdOptionExists(argv, argv + argc, "--region"))
-    {
-        region = s_getCmdOption(argv, argv + argc, "--region");
-    }
-
-    if (s_cmdOptionExists(argv, argv + argc, "--topic"))
-    {
-        topic = s_getCmdOption(argv, argv + argc, "--topic");
-    }
-
-    if (s_cmdOptionExists(argv, argv + argc, "--mode"))
-    {
-        mode = s_getCmdOption(argv, argv + argc, "--mode");
-    }
-
-    if (s_cmdOptionExists(argv, argv + argc, "--message"))
-    {
-        message = s_getCmdOption(argv, argv + argc, "--message");
-    }
-
-    if (s_cmdOptionExists(argv, argv + argc, "--proxy-host"))
-    {
-        proxyHost = s_getCmdOption(argv, argv + argc, "--proxy-host");
+        cmdUtils.PrintHelp();
+        exit(-1);
     }
-
-    if (s_cmdOptionExists(argv, argv + argc, "--proxy-port"))
+    certificatePath = cmdUtils.GetCommandRequired("cert");
+    keyPath = cmdUtils.GetCommandRequired("key");
+    thingName = cmdUtils.GetCommandRequired("thing_name");
+    caFile = cmdUtils.GetCommandOrDefault("ca_file", caFile);
+    region = cmdUtils.GetCommandOrDefault("region", region);
+    topic = cmdUtils.GetCommandOrDefault("topic", topic);
+    mode = cmdUtils.GetCommandOrDefault("mode", mode);
+    message = cmdUtils.GetCommandOrDefault("message", message);
+    proxyHost = cmdUtils.GetCommandOrDefault("proxy_host", proxyHost);
+    if (cmdUtils.HasCommand("proxy_port"))
     {
-        String portString = s_getCmdOption(argv, argv + argc, "--proxy-port");
+        String portString = cmdUtils.GetCommand("proxy_port");
         proxyPort = static_cast<uint16_t>(atoi(portString.c_str()));
     }
 

samples/greengrass/ipc/CMakeLists.txt

@@ -4,6 +4,8 @@ project(greengrass-ipc CXX)
 
 file(GLOB SRC_FILES
        "*.cpp"
+       "../../utils/CommandLineUtils.cpp"
+       "../../utils/CommandLineUtils.h"
 )
 
 add_executable(${PROJECT_NAME} ${SRC_FILES})

samples/greengrass/ipc/main.cpp

@@ -7,35 +7,14 @@
 
 #include <aws/greengrass/GreengrassCoreIpcClient.h>
 
+#include "../../utils/CommandLineUtils.h"
+
 using namespace Aws::Crt;
 using namespace Aws::Greengrass;
 
-static void s_printHelp()
-{
-    fprintf(stdout, "Usage:\n");
-    fprintf(stdout, "greengrass-ipc --topic <optional: topic> --message <optional: message to publish>\n\n");
-    fprintf(stdout, "topic: targeted topic. Default is test/topic\n");
-    fprintf(stdout, "message: message to publish. default 'Hello World'\n");
-}
-
 /* Used to check that the publish has been received so that the demo can exit successfully. */
 static std::atomic_bool s_publishReceived(false);
 
-bool s_cmdOptionExists(char **begin, char **end, const String &option)
-{
-    return std::find(begin, end, option) != end;
-}
-
-char *s_getCmdOption(char **begin, char **end, const String &option)
-{
-    char **itr = std::find(begin, end, option);
-    if (itr != end && ++itr != end)
-    {
-        return *itr;
-    }
-    return 0;
-}
-
 int main(int argc, char *argv[])
 {
     /************************ Setup the Lib ****************************/
@@ -48,21 +27,19 @@ int main(int argc, char *argv[])
     String message("Hello World");
 
     /*********************** Parse Arguments ***************************/
-    if (s_cmdOptionExists(argv, argv + argc, "--help"))
-    {
-        s_printHelp();
-        return 0;
-    }
+    Utils::CommandLineUtils cmdUtils = Utils::CommandLineUtils();
+    cmdUtils.RegisterProgramName("greengrass-ipc");
+    cmdUtils.AddCommonTopicMessageCommands();
+    const char **const_argv = (const char **)argv;
+    cmdUtils.SendArguments(const_argv, const_argv + argc);
 
-    if (s_cmdOptionExists(argv, argv + argc, "--topic"))
+    if (cmdUtils.HasCommand("help"))
     {
-        topic = s_getCmdOption(argv, argv + argc, "--topic");
-    }
-
-    if (s_cmdOptionExists(argv, argv + argc, "--message"))
-    {
-        message = s_getCmdOption(argv, argv + argc, "--message");
+        cmdUtils.PrintHelp();
+        exit(-1);
     }
+    topic = cmdUtils.GetCommandOrDefault("topic", topic);
+    message = cmdUtils.GetCommandOrDefault("message", message);
 
     /**
      * Create the default ClientBootstrap, which will create the default

samples/identity/fleet_provisioning/CMakeLists.txt

@@ -4,6 +4,8 @@ project(fleet-provisioning CXX)
 
 file(GLOB SRC_FILES
        "*.cpp"
+       "../../utils/CommandLineUtils.cpp"
+       "../../utils/CommandLineUtils.h"
 )
 
 add_executable(${PROJECT_NAME} ${SRC_FILES})

samples/identity/fleet_provisioning/main.cpp

@@ -32,47 +32,13 @@
 #include <string>
 #include <thread>
 
+#include "../../utils/CommandLineUtils.h"
+
 using namespace Aws::Crt;
 using namespace Aws::Iotidentity;
 using namespace std::this_thread; // sleep_for, sleep_until
 using namespace std::chrono;      // nanoseconds, system_clock, seconds
 
-static void s_printHelp()
-{
-    fprintf(stdout, "Usage:\n");
-    fprintf(
-        stdout,
-        "fleet-provisioning --endpoint <endpoint> --ca_file <optional: path to custom ca> --cert <path to cert>"
-        " --key <path to key> --templateName <template name> --templateParameters <template parameters> --csr "
-        "<optional: path to csr> \n\n");
-    fprintf(stdout, "endpoint: the endpoint of the mqtt server not including a port\n");
-    fprintf(stdout, "cert: path to your client certificate in PEM format\n");
-    fprintf(stdout, "csr: path to CSR in PEM format\n");
-    fprintf(stdout, "key: path to your key in PEM format\n");
-    fprintf(
-        stdout,
-        "ca_file: Optional, if the mqtt server uses a certificate that's not already"
-        " in your trust store, set this.\n");
-    fprintf(stdout, "\tIt's the path to a CA file in PEM format\n");
-    fprintf(stdout, "template_name: the name of your provisioning template\n");
-    fprintf(stdout, "template_parameters: template parameters json\n");
-}
-
-static bool s_cmdOptionExists(char **begin, char **end, const String &option)
-{
-    return std::find(begin, end, option) != end;
-}
-
-static char *s_getCmdOption(char **begin, char **end, const String &option)
-{
-    char **itr = std::find(begin, end, option);
-    if (itr != end && ++itr != end)
-    {
-        return *itr;
-    }
-    return 0;
-}
-
 static void sleep(int sleeptime)
 {
     std::cout << "Sleeping for " << sleeptime << " seconds..." << std::endl;
@@ -110,29 +76,29 @@ int main(int argc, char *argv[])
     apiHandle.InitializeLogging(Aws::Crt::LogLevel::Trace, stderr);
 
     /*********************** Parse Arguments ***************************/
-    if (!(s_cmdOptionExists(argv, argv + argc, "--endpoint") && s_cmdOptionExists(argv, argv + argc, "--cert") &&
-          s_cmdOptionExists(argv, argv + argc, "--key") && s_cmdOptionExists(argv, argv + argc, "--template_name") &&
-          s_cmdOptionExists(argv, argv + argc, "--template_parameters")))
+    Utils::CommandLineUtils cmdUtils = Utils::CommandLineUtils();
+    cmdUtils.RegisterProgramName("fleet-provisioning");
+    cmdUtils.AddCommonMQTTCommands();
+    cmdUtils.RegisterCommand("template_name", "<str>", "The name of your provisioning template");
+    cmdUtils.RegisterCommand("template_parameters", "<json>", "Template parameters json");
+    cmdUtils.RegisterCommand("csr", "<path>", "Path to CSR in PEM format (optional)");
+    const char **const_argv = (const char **)argv;
+    cmdUtils.SendArguments(const_argv, const_argv + argc);
+
+    if (cmdUtils.HasCommand("help"))
     {
-        s_printHelp();
-        return 0;
-    }
-
-    endpoint = s_getCmdOption(argv, argv + argc, "--endpoint");
-    certificatePath = s_getCmdOption(argv, argv + argc, "--cert");
-    keyPath = s_getCmdOption(argv, argv + argc, "--key");
-    templateName = s_getCmdOption(argv, argv + argc, "--template_name");
-    templateParameters = s_getCmdOption(argv, argv + argc, "--template_parameters");
-
-    if (s_cmdOptionExists(argv, argv + argc, "--ca_file"))
-    {
-        caFile = s_getCmdOption(argv, argv + argc, "--ca_file");
+        cmdUtils.PrintHelp();
+        exit(-1);
     }
-
-    // if CSRFile provided
-    if (s_cmdOptionExists(argv, argv + argc, "--csr"))
+    endpoint = cmdUtils.GetCommandRequired("endpoint");
+    certificatePath = cmdUtils.GetCommandRequired("cert");
+    keyPath = cmdUtils.GetCommandRequired("key");
+    templateName = cmdUtils.GetCommandRequired("template_name");
+    templateParameters = cmdUtils.GetCommandRequired("template_parameters");
+    caFile = cmdUtils.GetCommandOrDefault("ca_file", caFile);
+    if (cmdUtils.HasCommand("csr"))
     {
-        csrFile = getFileData(s_getCmdOption(argv, argv + argc, "--csr")).c_str();
+        csrFile = getFileData(cmdUtils.GetCommand("csr").c_str()).c_str();
     }
 
     /********************** Now Setup an Mqtt Client ******************/

samples/jobs/describe_job_execution/CMakeLists.txt

@@ -4,6 +4,8 @@ project(describe-job-execution CXX)
 
 file(GLOB SRC_FILES
        "*.cpp"
+       "../../utils/CommandLineUtils.cpp"
+       "../../utils/CommandLineUtils.h"
 )
 
 add_executable(${PROJECT_NAME} ${SRC_FILES})