Mainflux.mainflux/docs/dev-guide.md

Getting Mainflux

Mainflux can be fetched from official Mainflux GitHub repository:

mkdir -p $GOPATH/src/github.com/mainflux
cd $GOPATH/src/github.com/mainflux
git clone https://github.com/mainflux/mainflux.git
cd mainflux

Building

Prerequisites

Make sure that you have Protocol Buffers compiler (protoc) installed.

Go Protobuf installation instructions are here. Go Protobuf uses C bindings, so you will need to install C++ protobuf as a prerequisite.

Build All Services

Use GNU Make tool to build all mainflux services:

make

Build artefacts will be put in the build directory.

N.B. All Mainflux services are built as a statically linked binaries. This way they can be portable (transfered to any platform just by placing them there and running them) as they contain all needed libraries and do not relay on system shared libs. This helps creating FROM scratch dockers.

Build Individual Microservice

Individual microservices can be built with command:

make <microservice_name>

For example:

make http

will build HTTP Adapter microservice.

Building Dockers

Dockers can be built with:

make dockers

or individually with

make docker_<microservice_name>

For example:

make docker_http

N.B. Mainflux creates FROM scratch docker containers which as compact and small in size.

MQTT Microservice

MQTT Microservice in Mainflux is special, as it is currently the only microservice written in NodeJS. It is not compiled, but node modules need to be downloaded in order to start the service:

cd mqtt
npm install

Note that there is a shorthand for doing these commands with make tool:

make mqtt

After that MQTT Adapter can be started from top directory (as it needs to find *.proto files) with:

node mqtt/mqtt.js

Protobuf

Aforementioned make (which is an alias for make all target) is calling protoc command prior to compiling individual microservices.

To do this by hand, execute:

protoc --go_out=plugins=grpc:. *.proto

A shorthand to do this via make tool is:

make proto

N.B. This must be done one time in the beginning in order to generate protobuf Go structures needed for the build.

Cross-compiling for ARM

Mainflux can be compiled for ARM platform and run on Raspberry Pi or other similar IoT gateways.

Following the instructions here or here as well as information found here, environment variables GOARCH=arm and GOARM=7 must be set for the compilation.

Cross-compilation for ARM with Mainflux make:

GOOS=linux GOARCH=arm GOARM=7 make

Installing

Installing Go binaries is simple: just move them from build to $GOBIN (do not fortget to add $GOBIN to your $PATH).

You can execute:

make install

which will do this copy of binaries.

N.B. Only Go binaries will be installed this way. MQTT adapter is NodeJS script and will stay in mqtt dir.

Deployment

Prerequisites

Mainflux depends on several infrastructureal services, notably NATS broker and PostgreSQL database.

NATS

Mainflux uses NATS as it's central message bus. For development purposes (when not run via Docker), it expects that NATS is installed on the local system.

To do this execute:

go get github.com/nats-io/go-nats

This will install gnatsd binary that can be simply run by invoking

gnatsd

PostgreSQL

Mainflux uses PostgreSQL to store metadata (users, things and channels entities alongside with authorization tokens). It expects that PostgreSQL DB is installed, setu-up and running on the local system.

Inflormation how to set-up (prepare) PostgreSQL database can be found here, and it is done by executing following commands:

# Create `users` and `things` databases
sudo -u postgres createdb users
sudo -u postgres createdb things

# Set-up Postgres roles
sudo su - postgres
psql -U postgres
postgres=# CREATE ROLE mainflux WITH LOGIN ENCRYPTED PASSWORD 'mainflux';
postgres=# ALTER USER mainflux WITH LOGIN ENCRYPTED PASSWORD 'mainflux';

Mainflux Services

Running of the Mainflux microservices can be tricky, as there is a lot of them and each demand config in the form of environment variables.

Whole system (set of microservices) can be run with one command:

make run

which will properly configure and run all microservices.

Please assure that MQTT microservice has node_modules installed, as explained in MQTT Microservice chapter.

N.B. make run actually calls helper script scripts/run.sh, so you can inspect this script for the details.