hello_world example expanded with library option

WORKSPACE

@@ -205,7 +205,7 @@ new_local_repository(
     # For local MacOS builds, the path should point to an opencv@3 installation.
     # If you edit the path here, you will also need to update the corresponding
     # prefix in "opencv_macos.BUILD".
-    path = "/usr/local",
+    path = "/opt/homebrew",
 )
 
 new_local_repository(

mediapipe/examples/desktop/hello_world/BUILD

@@ -16,9 +16,10 @@ licenses(["notice"])
 
 package(default_visibility = ["//mediapipe/examples:__subpackages__"])
 
-cc_binary(
-    name = "hello_world",
+cc_library(
+    name = "hello_world_library",
     srcs = ["hello_world.cc"],
+    hdrs = ["hello_world.hh"],
     visibility = ["//visibility:public"],
     deps = [
         "//mediapipe/calculators/core:pass_through_calculator",
@@ -28,3 +29,11 @@ cc_binary(
         "//mediapipe/framework/port:status",
     ],
 )
+
+cc_binary(
+    name = "hello-world-binary",
+    srcs = ["hello-world-main.cc"],
+    deps = [
+        ":hello_world_library",
+    ],
+)

mediapipe/examples/desktop/hello_world/hello-world-main.cc

@@ -0,0 +1,7 @@
+#include "hello_world.hh"
+
+int main(int argc, char **argv)
+{
+    theFunctionToCall(argv[0]);
+    return 0;
+}

mediapipe/examples/desktop/hello_world/hello_world.cc

@@ -14,17 +14,18 @@
 //
 // A simple example to print out "Hello World!" from a MediaPipe graph.
 
+#include "hello_world.hh"
+
 #include "mediapipe/framework/calculator_graph.h"
 #include "mediapipe/framework/port/logging.h"
 #include "mediapipe/framework/port/parse_text_proto.h"
 #include "mediapipe/framework/port/status.h"
 
-namespace mediapipe {
-
-absl::Status PrintHelloWorld() {
+absl::Status PrintHelloWorld()
+{
   // Configures a simple graph, which concatenates 2 PassThroughCalculators.
-  CalculatorGraphConfig config =
-      ParseTextProtoOrDie<CalculatorGraphConfig>(R"pb(
+  mediapipe::CalculatorGraphConfig config =
+      mediapipe::ParseTextProtoOrDie<mediapipe::CalculatorGraphConfig>(R"pb(
         input_stream: "in"
         output_stream: "out"
         node {
@@ -39,29 +40,32 @@ absl::Status PrintHelloWorld() {
         }
       )pb");
 
-  CalculatorGraph graph;
+  mediapipe::CalculatorGraph graph;
   MP_RETURN_IF_ERROR(graph.Initialize(config));
-  ASSIGN_OR_RETURN(OutputStreamPoller poller,
+  ASSIGN_OR_RETURN(mediapipe::OutputStreamPoller poller,
                    graph.AddOutputStreamPoller("out"));
   MP_RETURN_IF_ERROR(graph.StartRun({}));
   // Give 10 input packets that contains the same string "Hello World!".
-  for (int i = 0; i < 10; ++i) {
+  for (int i = 0; i < 10; ++i)
+  {
     MP_RETURN_IF_ERROR(graph.AddPacketToInputStream(
-        "in", MakePacket<std::string>("Hello World!").At(Timestamp(i))));
+        "in", mediapipe::MakePacket<std::string>("Hello World!").At(mediapipe::Timestamp(i))));
   }
   // Close the input stream "in".
   MP_RETURN_IF_ERROR(graph.CloseInputStream("in"));
   mediapipe::Packet packet;
   // Get the output packets string.
-  while (poller.Next(&packet)) {
+  while (poller.Next(&packet))
+  {
     LOG(INFO) << packet.Get<std::string>();
   }
   return graph.WaitUntilDone();
 }
-}  // namespace mediapipe
 
-int main(int argc, char** argv) {
-  google::InitGoogleLogging(argv[0]);
-  CHECK(mediapipe::PrintHelloWorld().ok());
-  return 0;
+void theFunctionToCall(const char* argv0)
+{
+  google::InitGoogleLogging(argv0);
+  CHECK(PrintHelloWorld().ok());
 }
+
+

mediapipe/examples/desktop/hello_world/hello_world.hh

@@ -0,0 +1,3 @@
+#pragma once
+
+void theFunctionToCall(const char* argv0);