wlan-cloud-tools/microservice_sample_cpp

OpenWifi hello world (ow_helloworld)

What is this?

This is a skeleton Micro Service that shows off all the basic facilities of the OW architecture.

Building

In order to build the hello_world micro service, you will need to install its dependencies, which includes the following:

• cmake
• POCO 1.12 from Arilia
• C++17 compiler
• openssl
• libpq-dev (PortgreSQL development libraries)
• mysql-client (MySQL client)
• librdkafka
• cppkafka

The build is done in 2 parts. The first part is to build a local copy of the framework tailored to your environment. This framework is called Poco. The version used in this project has a couple of fixes from the master copy needed for cmake. Please use the version of this Poco fix. Building Poco may take several minutes depending on the platform you are building on.

Ubuntu/Debian

These instructions have proven to work on Ubuntu 20.4.

sudo apt install git cmake g++ libssl-dev libmariadb-dev 
sudo apt install libpq-dev libaprutil1-dev apache2-dev libboost-all-dev
sudo apt install librdkafka-dev // default-libmysqlclient-dev
sudo apt install nlohmann-json-dev

cd ~
git clone https://github.com/AriliaWireless/poco --branch poco-tip-v1
cd poco
mkdir cmake-build
cd cmake-build
cmake ..
cmake --build . --config Release
sudo cmake --build . --target install

cd ~
git clone https://github.com/AriliaWireless/cppkafka --branch tip-v1
cd cppkafka
mkdir cmake-build
cd cmake-build
cmake ..
cmake --build . --config Release
sudo cmake --build . --target install

cd ~
git clone https://github.com/pboettch/json-schema-validator.git --branch 2.1.0
cd json-schema-validator
mkdir cmake-build
cd cmake-build
cmake ..
make -j
sudo make install

git clone https://github.com/fmtlib/fmt --branch 9.0.0 /fmtlib
cd fmtlib
mkdir cmake-build
cd cmake-build
cmake ..
make
make install

cd ~
git clone https://github.com/Telecominfraproject/wlan-cloud-tools
cd wlan-cloud-tools
cd microservice_sample
mkdir cmake-build
cd cmake-build
cmake ..
make -j

Expected directory layout

From the directory where your cloned source is, you will need to create the certs, data, and logs directories.

mkdir certs
mkdir logs
mkdir data

Certificates

Love'em of hate'em, we gotta use'em. So we tried to make this as easy as possible for you.

The certs directory

For all deployments, you will need the following certs directory, populated with the proper files.

certs ---+
         +--- restapi-ca.pem
         +--- restapi-cert.pem
         +--- restapi-key.pem

Configuration

The configuration for this service is kept in a properties file. This file is called ow_helloworld.properties. The file will be loaded from root the directory set by the environment variable OWHELLOWORLD_CONFIG. To use environment variables in the configuration, you must use $<varname>. Only path names support the use of environment variables. The sample configuration requires very little changes if you keep the suggested directory structure. For the sample configuration to work, you need to define 2 environment variables.

export $OWHELLOWORLD_ROOT=`pwd`
export $OWHELLOWORLD_CONFIG=`pwd`

If your current working directory is the root of the project, this will set the variables properly. Otherwise, you can set the variables to point to wherever is necessary.

Important config entries

This is the type of storage in use

storage.type = sqlite

This is the RESTAPI endpoint

openwifi.restapi.host.0.backlog = 100
openwifi.restapi.host.0.security = relaxed
openwifi.restapi.host.0.rootca = $OWHELLOWORLD_ROOT/certs/restapi-ca.pem
openwifi.restapi.host.0.address = *
openwifi.restapi.host.0.port = 16051
openwifi.restapi.host.0.cert = $OWHELLOWORLD_ROOT/certs/restapi-cert.pem
openwifi.restapi.host.0.key = $OWHELLOWORLD_ROOT/certs/restapi-key.pem
openwifi.restapi.host.0.key.password = mypassword

openwifi.internal.restapi.host.0.backlog = 100
openwifi.internal.restapi.host.0.security = relaxed
openwifi.internal.restapi.host.0.rootca = $OWHELLOWORLD_ROOT/certs/restapi-ca.pem
openwifi.internal.restapi.host.0.address = *
openwifi.internal.restapi.host.0.port = 17051
openwifi.internal.restapi.host.0.cert = $OWHELLOWORLD_ROOT/certs/restapi-cert.pem
openwifi.internal.restapi.host.0.key = $OWHELLOWORLD_ROOT/certs/restapi-key.pem
openwifi.internal.restapi.host.0.key.password = mypassword

This is the end point for the devices to connect with

2 types of endpoints: restapi and internal.

restapi

This is the public side of the API. This should always be secured and exposed through your container or a firewall. This should be protected. The IP address use by this interface should have an FQDN matching its certificate. That certificate and key are in openwifi.restapi.host.0.cert and openwifi.restapi.host.0.key. The port you specify under openwifi.restapi.host.0.port is the one you will use in your URIs to get into the micro service. This should be open in your firewall or docker container.

internal

This is the private side of the API. This should never be exposed through your container or a firewall. This should be protected. That certificate and key are in openwifi.restapi.host.0.cert and openwifi.restapi.host.0.key. The port you specify under openwifi.restapi.host.0.port is the one you will use in your URIs to get into the micro service behind the firewall or using docker networking. This port is assumed secured. Never expose it.

Command line options

The current implementation supports the following. If you use the built-in configuration file, you do not need to use any command-line options. However, you may decide to use the --daemon or umask options.

./ow_helloworld --help
usage: ow_helloworld OPTIONS
A ow_helloworld implementation for TIP.

--daemon        Run application as a daemon.
--umask=mask    Set the daemon's umask (octal, e.g. 027).
--pidfile=path  Write the process ID of the application to given file.
--help          display help information on command line arguments
--file=file     specify the configuration file
--debug         to run in debug, set to true
--logs=dir      specify the log directory and file (i.e. dir/file.log)

file

This allows you to point to another file without specifying the OWHELLOWORLD_CONFIG variable. The file name must end in .properties.

daemon

Run this as a UNIX service

pidfile

When running as a daemon, the pid of the running service will be set in the specified file

debug

Run the service in debug mode.

logs

Specify where logs should be kept. You must include an existing directory and a file name. For example /var/ucentral/logs/log.0.

umask

Set the umask for the running service.

ALB Support

Support for AWS ALB is provided through the following configuration elements. This is the built-in AWS Application Load Balancer

alb.enable = true
alb.port = 16102

Kafka integration

So what about Kafka? Well, the micro service framework has basic integration with Kafka. It is turned off by default, to turn it on, in the configuration:

openwifi.kafka.group.id = hello_world
openwifi.kafka.client.id = hello_world1
openwifi.kafka.enable = false
openwifi.kafka.brokerlist = kafka:9092
openwifi.kafka.commit = false
openwifi.kafka.queue.buffering.max.ms = 50
openwifi.kafka.ssl.ca.location =
openwifi.kafka.ssl.certificate.location =
openwifi.kafka.ssl.key.location =
openwifi.kafka.ssl.key.password =

openwifi.kafka.group.id

This must be set to your service's name and should be unique

openwifi.kafka.client.id

This must be set to your service's name and should be unique

openwifi.kafka.enable

Kind of obvious but hey, set true or false. Default is false

openwifi.kafka.brokerlist

This is a comma separator list of the brokers in your kafka deployment. If you are using Docker, this will usually be something like kafka:9092. If you are using an external Kafka cluster, kafka-cluster.domain.com:9092.

Kafka topics

To read more about Kafka, follow the document

Securing kafka

This is beyond the scope of this document. As it stands today, the communication between the gateway and kafka is expected to be behind a firewall. However, the framework also allows secure Kafka access. To use secured access, you must fill the fields that start with openwifi.kafka.ssl.

Make it into a docker container

Do be easily deployed, your micro service should be dockerrised. The sample included here has all the basic templates to be dockerized and fit into the other micro services that make up TIPOpenWifi 2.0. Here ate the files you should look at

Dockerfile

This is the basic Dockerfile that includes building all the dependencies for a micro service. You will find all the information towards the end of the file. You should look for ow_helloworld and replace by you own micro srvice name. Replace also allo the default ports

docker-entrypoint.sh

This is the docker entry point file. It uses several environment varialbles set up in the Dockerfile itself.

ow_helloworld.properties.tmpl

This is a template file used to deploy your micro service. It is used to create a default properties file.

More docker

This is how Docker is currently done in TIP OpenWifi 2.0. For more information, please look at the other micro services.

Running as compiled source

If you want to run as compile source while debugging, the file ow_hwlloworld.service is a Linux systemd service file. Replace the obvious directories and names with your information. Follow the standard way of installing and enabling this file using systemctl.

Contributors

We love ya! We need more of ya! If you want to contribute, make sure you review the coding style document. Feel free to ask questions and post issues.