Add github action entrypoint.

entrypoint.sh

@@ -1,5 +1,29 @@
 #!/bin/sh -l
+set -o pipefail
 
-echo "Hello $1"
+FLAGS=""
 
-echo "::set-output name=semver::$time"
+if [[ -z "$INPUT_CONFIG_FILE" ]]; then
+  echo "Set the configuration file path."
+  exit 1
+else
+  FLAGS+=" -c $INPUT_CONFIG_FILE"
+fi
+
+if [[ -z "$INPUT_REPOSITORY_URL" ]] && [[ -z "$INPUT_REPOSITORY_LOCAL" ]];
+then
+  echo "You need to set either remote repository or repository local flags."
+  exit 1
+fi
+
+if [[ ! -z "$INPUT_REPOSITORY_URL" ]]; then
+  FLAGS+=" -r $INPUT_REPOSITORY_URL"
+fi
+
+if [[ ! -z "$INPUT_REPOSITORY_LOCAL" ]]; then
+  FLAGS+=" -l"
+fi
+
+OUT_SEMVER_GEN=$(./semver-gen generate generate $FLAGS)
+OUT_SEMVER=$(echo $OUT_SEMVER_GEN | sed -e 's|SEMVER ||g')
+echo "::set-output name=semver::$OUT_SEMVER"