Developing Built-in Native Services

To create a built-in native service, you must write the source code and prepare the required configuration files.

For easier understanding, the process to create a built-in JS service is explained using using a sample service in Sample Code Repository. The sample service has the following features:

• Has a method named hello that responds with the string “Hello, Native Service!!”.
• Calls com.webos.service.systemservice/clock/getTime method and prints the UTC time on the log.

The directory structure of the sample service must be as follows:

native-services/built-in/
├── build-config/
│   ├── com.example.service.native.bb
│   └── webos-local.conf
└── com.example.service.native/
    ├── files/
    │   ├── sysbus/
    │   │   ├── com.example.service.native.api.json.in
    │   │   ├── com.example.service.native.groups.json.in
    │   │   ├── com.example.service.native.perm.json.in
    │   │   ├── com.example.service.native.role.json.in
    │   │   └── com.example.service.native.service.in
    │   └── systemd/
    │       └── com.example.service.native.service.in
    ├── CMakeLists.txt
    ├── main.cpp
    └── README.md

Developing a built-in native service requires the following steps:

• Prerequisites
• Step 1: Implementation
• Step 2: Configuration
• Step 3: Build
• Step 4: Verification
• Step 5: Deployment

Before you begin

• Build and flash the webOS OSE image. For detailed information, see Building webOS OSE and Flashing webOS OSE.

• Download the sample repository, and move into samples/native-services/built-in directory.

  $ git clone https://github.com/webosose/samples
  $ cd samples/native-services/built-in
  

Step 1: Implement the Native Service

Source Code

First, define the functionality of the native service on the source code.

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#include <glib.h>
#include <string>
#include <luna-service2/lunaservice.h>
#include <PmLog.h>
#include <pbnjson.hpp>

static PmLogContext getPmLogContext()
{
    static PmLogContext s_context = 0;
    if (0 == s_context)
    {
        PmLogGetContext("NativeService", &s_context);
    }
    return s_context;
}

static pbnjson::JValue convertStringToJson(const char *rawData)
{
    pbnjson::JInput input(rawData);
    pbnjson::JSchema schema = pbnjson::JSchemaFragment("{}");
    pbnjson::JDomParser parser;
    if (!parser.parse(input, schema))
    {
        return pbnjson::JValue();
    }
    return parser.getDom();
}

static std::string convertJsonToString(const pbnjson::JValue json)
{
    return pbnjson::JGenerator::serialize(json, pbnjson::JSchemaFragment("{}"));
}

static bool onHello(LSHandle *sh, LSMessage* message, void* ctx)
{
    PmLogInfo(getPmLogContext(), "HANDLE_HELLO", 0, "hello method called");

    pbnjson::JValue reply = pbnjson::Object();
    if (reply.isNull())
        return false;

    reply.put("returnValue", true);
    reply.put("answer", "Hello, Native Service!!");

    LSError lserror;
    LSErrorInit(&lserror);

    if (!LSMessageReply(sh, message, reply.stringify().c_str(), &lserror))
    {
        PmLogError(getPmLogContext(), "HANDLE_HELLO", 0, "Message reply error!!");
        LSErrorPrint(&lserror, stdout);

        return false;
    }
    return true;
}

static bool cbGetTime(LSHandle *sh, LSMessage *msg, void *user_data)
{
    LSError lserror;
    LSErrorInit(&lserror);

    PmLogInfo(getPmLogContext(), "GETTIME_CALLBACK", 1, PMLOGJSON("payload", LSMessageGetPayload(msg)),  " ");

    pbnjson::JValue response = convertStringToJson(LSMessageGetPayload(msg));
    bool successCallback = response["returnValue"].asBool();
    if (successCallback)
    {
        int64_t utc= response["utc"].asNumber<int64_t>();
        PmLogInfo(getPmLogContext(), "GETTIME_CALLBACK", 1, PMLOGKFV("UTC", "%lld", utc),  " ");
    }

    return true;
}

static LSMethod serviceMethods[] = {
    { "hello", onHello }
};

int main(int argc, char* argv[])
{
    PmLogInfo(getPmLogContext(), "SERVICE_MAIN", 0, "start com.example.service.native");

    LSError lserror;
    LSErrorInit(&lserror);

    GMainLoop* mainLoop = g_main_loop_new(nullptr, false);
    LSHandle *m_handle = nullptr;

    if(!LSRegister("com.example.service.native", &m_handle, &lserror))
    {
        PmLogError(getPmLogContext(), "LS_REGISTER", 0, "Unable to register to luna-bus");
        LSErrorPrint(&lserror, stdout);

        return false;
    }

    if (!LSRegisterCategory(m_handle, "/", serviceMethods, NULL, NULL, &lserror))
    {
        PmLogError(getPmLogContext(), "LS_REGISTER", 0, "Unable to register category and method");
        LSErrorPrint(&lserror, stdout);

        return false;
    }

    if(!LSGmainAttach(m_handle, mainLoop, &lserror))
    {
        PmLogError(getPmLogContext(), "LS_REGISTER", 0, "Unable to attach service");
        LSErrorPrint(&lserror, stdout);

        return false;
    }

    if (!LSCall(m_handle,
                "luna://com.webos.service.systemservice/clock/getTime",
                "{}",
                cbGetTime,
                NULL,
                NULL,
                &lserror))
    {
        PmLogError(getPmLogContext(), "LSCALL_GETTIME", 0, "Cannot call getTime");
        LSErrorPrint(&lserror, stderr);
    }

    g_main_loop_run(mainLoop);

    if(!LSUnregister(m_handle, &lserror))
    {
        PmLogError(getPmLogContext(), "LS_REGISTER", 0, "Unable to unregister service");
        LSErrorPrint(&lserror, stdout);

        return false;
    }

    g_main_loop_unref(mainLoop);
    mainLoop = nullptr;

    return 0;
}

A brief explanation of the above file:

• Line(3~5) : Include header files to use LS2, PmLog, and pbnjson.
• Line(7~15) : A function that calls PmLogGetContext() in PmLog library to print logs. For more details, see Using PmLogLib in C/C++.
• Line(17~32) : Create pbnjson utility functions, which convert String to Json and Json to String based on pbnjson library. pbnjson is a JSON engine, implemented as a pair of libraries with APIs for easier C and C++ abstraction.
• Line(34~56) : Implement the onHello() callback function that is invoked when com.example.service.native/hello is called. The third argument of LSMessageReply() should be in JSON format.
• Line(58~74) : Implement the cbGetTime() callback function for systemservice’s getTime method call. When the UTC time is received in response, this function prints the time on the log.
• Line(76~78) : Register the hello method and the onHello() callback function in the LSMethod array.
• Line(84~85) : Declare and initialize LSError.
• Line(87~88) : Declare GMainLoop and LSHandle variables.
• Line(90~96) : Register the com.example.service.native service using LSRegister().
• Line(98~104) : Register the hello method and the onHello() callback function in LSHandle (m_handle).
• Line(106~112) : Attach the com.example.service.native service to GMainLoop.
• Line(114~124) : Call systemservice’s getTime method using LSCall().
• Line(126) : Run an iteration loop.
• Line(128~134) : After the iteration loop is stopped, unregister the service.
• Line(136~137) : Release GMainLoop.

README.md

This file provides general information of the native service.

Summary
-------
native service sample

Description
-----------
native service sample

How to Build on Linux
---------------------

## Dependencies

Below are the tools and libraries (and their minimum versions) required to build sample program:

* cmake (version required by cmake-modules-webos)
* gcc
* glib-2.0
* make
* cmake-modules-webos

## Building

    $ cd build-webos
    $ source oe-init-build-env
    $ bitbake com.example.service.native

Copyright and License Information
=================================
Unless otherwise specified, all content, including all source code files and
documentation files in this repository are:

Copyright (c) 2020 LG Electronics, Inc.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

SPDX-License-Identifier: Apache-2.0

Step 2: Configure the Native Service

This section describes how to prepare the configuration files required to build and test the native service.

LS2 Configuration Files

To register and execute a service through LS2, it is necessary to create a Service Configuration file, Role file, Permission file, and Groups file. You must create a files/sysbus directory in your project so that the configuration files are installed in the right place on the target.

Service Configuration File

This file contains description of the service type and launch command.

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[D-BUS Service]
Name=com.example.service.native
Exec=@WEBOS_INSTALL_SBINDIR@/com.example.service.native
Type=static

A brief explanation of the above file:

• Line(1) : Write “[D-BUS Service]” on the first line.
• Line(2) : Set com.example.service.native to service name.
• Line(3) : Write the full path of the executable file. @WEBOS_INSTALL_SBINDIR@ stands for ‘/usr/sbin’ directory.
• Line(4) : Type can be set to ‘static’ or ‘dynamic’. In this example, it is set as a static service.

Role File

This file contains allowed service names for each component and individual security settings for each service name.

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{
    "exeName":"@WEBOS_INSTALL_SBINDIR@/com.example.service.native",
    "type": "regular",
    "trustLevel": "oem",
    "allowedNames": [
        "com.example.service.native"
    ],
    "permissions": [
        {
            "service":"com.example.service.native",
            "outbound":[
                "*"
            ]
        }
    ]
}

A brief explanation of the above file:

• Line(2) : exeName - Specify the full path to the binary for a native service. Must be of the form: “/path/to/binary”
• Line(3) : type - Indicate whether the app is privileged (can change its role) or regular. Possible values are privileged or regular.
• Line(4) : Set the trust level of the service.
• Line(5~7) : allowedNames - Names that this service is allowed to register. It can be an array of any valid service name strings, empty array [] for none, and empty string "" for an unnamed service.
• Line(8~15) : The permissions for the service.
  • outbound - Array of services that this service is allowed to send requests to. It can include strings of any valid service names. Use “*” for all, empty array [] for none, and empty string "" for unnamed services. It’s possible to use a wildcard (*) at the end of a string.

Client Permission File

This file defines what groups are required for this component to function properly.

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{
    "com.example.service.native": [
        "time.query"
    ]
}

A brief explanation of the above file:

• Line(3) : Since com.example.service.native calls systemservice’s getTime method, add the method’s group name “time.query” to the client permission file.

API Permission File

This file defines ACG values of the service and methods those ACG values contain.

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{
    "examplenativeservice.acgvalue": [
        "com.example.service.native/hello"
    ]
}

A brief explanation of the above file:

• Line(3) : Set an ACG value and specify the methods that belong to the ACG value. In this example, the ACG value is “examplenativeservice.acgvalue”, and the com.example.service.native/hello method is added to this value.

Groups File

This file defines the trust levels of each ACG value.

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{
    "allowedNames": [ "com.example.service.js" ],
    "examplenativeservice.acgvalue": [ "oem" ]
}

A brief explanation of the above file:

• Line(3) : Set the trust level for examplenativeservice.acgvalue as oem. So the APIs in examplenativeservice.acgvalue have the oem trust level.

Systemd Configuration File

This file is required to run the services provided by systemd.

This file will be installed to the target as com.example.service.native.

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[Unit]
Description=webos - "%n"
Requires=ls-hubd.service
After=ls-hubd.service

[Service]
Type=simple
OOMScoreAdjust=-500
EnvironmentFile=-/var/systemd/system/env/com.example.service.native.env
Environment=CHARSET=UTF-8
ExecStart=/usr/sbin/com.example.service.native
Restart=on-failure

A brief explanation of the above file:

• Line(3) : Describe the dependency of service execution. If the dependent unit is normal, the unit is started. The example allows the ls-hubd.service unit to run and then run the service.
• Line(11) : Set the path to the executable file.

For more details, see systemd official site.

CMakeLists.txt

This file is required to build the source code using CMake.

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cmake_minimum_required(VERSION 2.8.7)
project(com.example.service.native CXX)
set(CMAKE_BUILD_TYPE Debug)

include(webOS/webOS)
webos_modules_init(1 6 3)
webos_component(0 0 1)

include(FindPkgConfig)

pkg_check_modules(GLIB2 REQUIRED glib-2.0)
include_directories(${GLIB2_INCLUDE_DIRS})
webos_add_compiler_flags(ALL ${GLIB2_CFLAGS_OTHER})

pkg_check_modules(LUNASERVICE2 REQUIRED luna-service2)
include_directories(${LUNASERVICE2_INCLUDE_DIRS})
webos_add_compiler_flags(ALL ${LUNASERVICE2_CFLAGS_OTHER})

pkg_check_modules(PMLOG REQUIRED PmLogLib)
include_directories(${PMLOG_INCLUDE_DIRS})
webos_add_compiler_flags(ALL ${PMLOG_CFLAGS_OTHER})

pkg_check_modules(PBNJSON_CPP REQUIRED pbnjson_cpp)
include_directories(${PBNJSON_CPP_INCLUDE_DIRS})
webos_add_compiler_flags(ALL ${PBNJSON_CPP_CFLAGS_OTHER})

set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
set(SRCS main.cpp)

add_executable(${PROJECT_NAME} ${SRCS})

SET (EXT_LIBS
    ${GLIB2_LDFLAGS}
    ${LUNASERVICE2_LDFLAGS}
    ${PMLOG_LDFLAGS}
    ${PBNJSON_CPP_LDFLAGS}
)

target_link_libraries(${PROJECT_NAME} ${EXT_LIBS})

install(TARGETS ${PROJECT_NAME} DESTINATION ${WEBOS_INSTALL_SBINDIR})

webos_build_system_bus_files()
webos_build_configured_file(files/systemd/com.example.service.native.service SYSCONFDIR systemd/system)

A brief explanation of the above file:

• Line(2) : Specify the project name and the file extension type. In this tutorial, we use “com.example.service.native” as the project name for indicating various filenames and pathnames. The file extension type allows CMake to skip unnecessary compiler checks.
• Line(5) : Include webOS OSE modules for the build.
• Line(6) : Specify the “cmake-modules-webos” version.
• Line(7) : Specify webos_component with the component version to use webOS variables for the standard system paths. It commonly follows three digit versioning scheme.
• Line(9~39) : Add GLib, LS2, PmLogLib, and pbnjson dependencies, and add options to use C++11.
• Line(41) : Install the executable in /usr/sbin.
• Line(43) : Install the LS2 configuration files (/files/sysbus) to the target.
• Line(44) : Install the systemd configuration file on the target (etc/systemd/system).

Step 3: Build the Native Service

After implementing and configuring the Native service, you must build the service.

Add the Recipe File

webOS OSE uses OpenEmbedded of Yocto Project to build its components. OpenEmbedded needs a recipe file that configures the build environment. For more details about the recipe, see Yocto Project Reference Manual.

You must move the recipe file into webOS OSE project directory.

• Recipe file: samples/native-services/built-in/build-config/com.example.service.native.bb
• Destination directory: build-webos/meta-webosose/meta-webos/recipes-webos/<native service name>

where <native service name> is the name of the native service. For the sample native service, <native service name> must be replaced by ‘com.example.service.native’.

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SUMMARY = "Native service sample"
AUTHOR = "Author's name <Author's e-mail>"
LICENSE = "Apache-2.0"
LIC_FILES_CHKSUM = "file://${COMMON_LICENSE_DIR}/Apache-2.0;md5=89aea4e17d99a7cacdbeed46a0096b10"

DEPENDS= "glib-2.0 luna-service2 pmloglib libpbnjson"

WEBOS_VERSION = "0.0.1"
PR = "r0"

inherit webos_component
inherit webos_submissions
inherit webos_daemon
inherit webos_cmake
inherit webos_system_bus

A brief explanation of the above file:

• Lines(1~4) : Basic descriptions of the component.
• Line(6) : Add GLib, LS2, PmLog, and pbnjson as dependencies.
• Line(8) : Version of the component. For the webOS OSE component, this field is mandatory.
• Line(9) : Revision version of the recipe. Each recipe requires a counter to track its modification history. Make sure that you increment the version when you edit the recipe, unless you only change the value of the WEBOS_VERSION field or comments.
• Line(11) : Inherit common functions of webOS OSE. For all components of webOS OSE, this entry is required.
• Line(12) : Instruct OpenEmbedded to use the WEBOS_VERSION value as the component version number. If you develop your component on a local repository, this entry is required.
• Line(13) : Every component that installs a daemon inherits webos_daemon.
• Line(14) : Instruct OpenEmbedded that the component uses CMake for configuration, which is the preferred choice for webOS components.
• Line(15) : To register component as a service and install LS2 configuration files, inherit webos_system_bus.

Configure the Local Source Directory

To build a component that is located on the local system, you must specify the directory information.

You must move the configuration file into webOS OSE project directory.

• Configuration file: samples/native-services/built-in/build-config/webos-local.conf
• Destination directory: build-webos

For the sample native service (com.example.service.native), you must provide the local path where the source exists.

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INHERIT += "externalsrc"
EXTERNALSRC:pn-com.example.service.native = "/home/username/project/com.example.service.native/"
EXTERNALSRC_BUILD:pn-com.example.service.native = "/home/username/project/com.example.service.native/build/"
PR:append:pn-com.example.service.native =".local0"

A brief explanation of the above file:

• Line(1) : Inherit “externalsrc” bbclass file.
• Line(2) : The local source directory. The syntax of the property is EXTERNALSRC:pn-<component>. For the value, input "<absolute path of the project directory>"
• Line(3) : The local build directory. The syntax of the property is EXTERNALSRC_BUILD:pn-<component>. For the value, input "<absolute path of the project directory>/build/"
• Line(4) : The appended revision version (PR) for building local source files. The syntax of the property is PR:append:pn-<component>. This property is optional.

Build the Service

To build the component on the OpenEmbedded environment, enter the following commands on the shell.

build-webos$ source oe-init-build-env
build-webos$ bitbake com.example.service.native

Step 4: Run and Verify the Native Service

After building the service, you must verify its functionality.

1. Copy the IPK to the target.

   When the build is successful, oe-related directories are created under the project root directory. These directories are linked to the directory where the build output is generated from the actual build-webos sub-directory.

   com.example.service.native
   ├── CMakeLists.txt
   ├── README.md
   ├── files
   │   ├── sysbus
   │   │   ├── com.example.service.native.api.json.in
   │   │   ├── com.example.service.native.groups.json.in
   │   │   ├── com.example.service.native.perm.json.in
   │   │   ├── com.example.service.native.role.json.in
   │   │   └── com.example.service.native.service.in
   │   └── systemd
   │       └── com.example.service.native.service.in
   ├── main.cpp
   ├── oe-logs -> /home/username/build/build-webos/BUILD/work/raspberrypi4_64-webos-linux/com.example.service.native/0.0.1-r0.local0/temp
   ├── oe-workdir -> /home/username/build/build-webos/BUILD/work/raspberrypi4_64-webos-linux/com.example.service.native/0.0.1-r0.local0
   

   If you go to oe-workdir/deploy-ipks/raspberrypi4_64, you can see com.example.service.native_0.0.1-r0.local0_raspberrypi4_64.ipk file.

   com.example.service.native/oe-workdir/deploy-ipks/raspberrypi4_64
   └── com.example.service.native_0.0.1-r0.local0_raspberrypi4_64.ipk
   

   Copy the IPK file to the target device using the scp command.

   com.example.service.native/oe-workdir/deploy-ipks/raspberrypi4_64$ scp com.example.service.native_0.0.1-r0.local0_raspberrypi4_64.ipk root@<target IP address>:/media/internal/downloads
   

2. Install the service on the target.

   Connect to the target using the ssh command and install com.example.service.native_0.0.1-r0.local0_raspberrypi4_64.ipk.

   $ ssh root@<target IP address>
   root@raspberrypi4-64:/sysroot/home/root# cd /media/internal/downloads/
   root@raspberrypi4-64:/media/internal/downloads# opkg install com.example.service.native_0.0.1-r0.local0_raspberrypi4_64.ipk
   
   Installing com.example.service.native (0.0.1) on root.
   Configuring com.example.service.native.
   

3. Discover the LS2 configuration files.

   To make LS2 daemon scan the LS2 configuration files of the service, use the ls-control command as follows.

   root@raspberrypi4-64:/media/internal/downloads# ls-control scan-services
   
   telling hub to reload setting and rescan all directories
   

4. Run the service.

   You can run the com.example.service.native using the systemctl command.

   root@raspberrypi4-64:/# systemctl start com.example.service.native
   

5. Verify the execution of the service.

   • Using systemctl

     You can check the PID and attribute of the executed process using the command systemctl status.

     [[0;1;32m●[[0m com.example.service.native.service - webos - "com.example.service.native.service"
        Loaded: loaded (/etc/systemd/system/com.example.service.native.service; static; vendor preset: enabled)
        Active: [[0;1;32mactive (running)[[0m since Sun 2019-05-26 19:19:38 PDT; 2min 35s ago
     Main PID: 3264 (com.example.ser)
        CGroup: /system.slice/com.example.service.native.service
                └─3264 /usr/sbin/com.example.service.native
     

   • Using the log file

     You can use the journalctl command on the target for debugging the native service. For details on how to use the command, see Viewing Logs.

     root@raspberrypi4-64:/# journalctl -f | grep NativeService
     
     Nov 22 15:56:50 raspberrypi4-64 com.example.service.native[1767]: [] [pmlog] NativeService SERVICE_MAIN {} start com.example.service.native
     Nov 22 15:56:50 raspberrypi4-64 com.example.service.native[1767]: [] [pmlog] NativeService GETTIME_CALLBACK {"payload":{"source":"system","returnValue":true,"offset":{"source":"system","value":0},"utc":1637625410,"systemTimeSource":"ntp","timestamp":{"source":"monotonic","sec":10844,"nsec":109477350}}}
     Nov 22 15:56:50 raspberrypi4-64 com.example.service.native[1767]: [] [pmlog] NativeService GETTIME_CALLBACK {"UTC":1637625410}
     

6. Verify the Output.

   Verify the output of the hello Method. You can call a method by using the luna-send command:

   root@raspberrypi4-64:/# luna-send -n 1 -f luna://com.example.service.native/hello '{}'
   {
       "answer": "Hello, Native Service!!",
       "returnValue": true
   }
   

   For more details, see Introduction to LS2 API.

   Note
   

   If com.example.service.native is not registered successfully, you will see a return message as below.

   root@raspberrypi4-64:/# luna-send -n 1 -f luna://com.example.service.native/hello '{}'
   {
       "errorCode": -1,
       "returnValue": false,
       "errorText": "Service does not exist: com.example.service.native."
   }
   

7. Specify the Order of Execution on the Target

   To verify that the service can run automatically after rebooting, add the service to the systemd’s start execution list. This ensures that the service runs automatically without the systemctl start command.

   • Update the file: webos-bd.target
   • Directory: /etc/systemd/system (on the target device)

   [Unit]
   Description="%n"
   Wants=nyx-utils.service \
         second-screen-gateway.service \
         com.example.service.native.service
   

Step 5: Deploy the Native Service

Now you are ready to package the native service in the webOS image.

Add the Service to Build Recipe

Add the service to the package recipe file.

• Update the file: packagegroup-webos-extended.bb

• Directory: build-webos/meta-webosose/meta-webos/recipes-core/packagegroups

• Updates to be made: Add the service name to RDEPENDS:${PN} =

...
RDEPENDS:${PN} = " \
    activitymanager \
    audiod \
    ...
    com.example.service.native \
    ${VIRTUAL-RUNTIME_appinstalld} \
    ...

For more details, see Yocto Project Reference Manual.

Modify Systemd Execution List on webos-initscripts

Modify the webos-initscripts component which is responsible for systemd configuration in webOS. Through this process, you can learn how to modify a built-in component in webOS.

1. Download the webos-initscripts component source from GitHub repository to your local system.

   In this document, we download the webos-initscripts component to ~/project/webOS/webos-initscripts.

   ~/project/webOS$ git clone https://github.com/webosose/webos-initscripts.git
   

2. Specify the order of execution of the newly created native service.

   In this example, adding the service to the last line ensures that it is executed last.

   • Update the file: webos-bd.target

   • Directory: ~/project/webOS/webos-initscripts/files/systemd/targets

   • Updates: Add the service name (com.example.service.native.service) to the last line.

   [Unit]
   Description="%n"
   Wants=nyx-utils.service \
               second-screen-gateway.service \
               com.example.service.native.service
   

3. Specify the path of the webos-initscripts local source directory in the build.

   • Update the file: webos-local.conf

   • Directory: build-webos

   INHERIT += "externalsrc"
   EXTERNALSRC:pn-com.example.service.native = "/home/username/project/webOS/com.example.service.native/"
   EXTERNALSRC_BUILD:pn-com.example.service.native = "/home/username/project/webOS/com.example.service.native/build/"
   PR:append:pn-com.example.service.native =".local0"
   EXTERNALSRC:pn-webos-initscripts = "/home/username/project/webOS/webos-initscripts/"
   EXTERNALSRC_BUILD:pn-webos-initscripts = "/home/username/project/webOS/webos-initscripts/build"
   PR:append:pn-webos-initscripts =".local0"
   

4. Build webos-initscripts on build-webos.

   We can check webos-initscripts on local directory if built successfully.

   build-webos$ source oe-init-build-env
   build-webos$ bitbake webos-initscripts
   

Build the webOS OSE Image and Flash to the Target

1. Build the webos-image.

   build-webos$ source oe-init-build-env
   build-webos$ bitbake webos-image
   

2. Flash the generated webos-image to SD card.

   build-webos/BUILD/deploy/images/raspberrypi4-64$ sudo dd bs=4M if=webos-image-raspberrypi4-64.rootfs.wic of=/dev/sdc
   

   For more details, see the Flashing webOS OSE page.

3. After booting, connect to the target with SSH.

   If you check the service list with ls-monitor, you can see com.example.service.native is executed as static type.

   $ ssh root@<target IP address>
   root@raspberrypi4-64:/sysroot/home/root# ls-monitor -l | grep example
   542           com.example.service.native        /usr/sbin/com.example.service.native    static                  4dTPKKQI