taka-wang / psmb

Proactive service for modbusd written in Golang.

psmb

Proactive service library for modbusd

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Continuous Integration

I do continuous integration and deploy docker images after git push by self-hosted drone.io server, circleci service, codecov service and dockerhub service.

CI Server	Target	Status
CircleCI	x86
Travis	x86
Drone	armhf

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Environment variables

Why environment variable? Refer to the 12 factors

• CONF_PSMBTCP: config file path
• EP_BACKEND: endpoint of remote service discovery server (optional)

Contracts (Interfaces)

• IProactiveService: proactive service
• IReaderTaskDataStore: read/poll task data store
• IWriterTaskDataStore: write task data store
• IHistoryDataStore: history data store
• IFilterDataStore: filter data store
• IConfig: config management

Golang package management

• I adopted glide as package management system for this repository.

Worker Pool Model

Request from upstream

Response from downstream

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Up and Running

Docker Compose

docker-compose build --pull
docker-compose up

Manually

Install libzmq (3.2.5)

wget https://github.com/zeromq/zeromq3-x/releases/download/v3.2.5/zeromq-3.2.5.tar.gz
tar xvzf zeromq-3.2.5.tar.gz
cd zeromq-3.2.5
./configure
make
sudo make install
sudo ldconfig

Build

# install glide
curl https://glide.sh/get | sh

# install dependencies
glide up

# build
cd tcp-srv
go build -o psmbtcp-srv

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Deployment Diagram

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Unit tests

• binary
• types

Test cases

Binary

• Bytes to 16-bit integer array tests
  • BytesToUInt16s in big endian order - (1/4)
  • BytesToUInt16s in little endian order - (2/4)
  • BytesToInt16s in big endian order - (3/4)
  • BytesToInt16s in little endian order - (4/4)
• Bytes to 32-bit integer array tests
  • BytesToUInt32s in (ABCD) Big Endian order - (1/4)
  • BytesToUInt32s in (DCBA) Little Endian order - (2/4)
  • BytesToUInt32s in (BADC) Mid-Big Endian order - (3/4)
  • BytesToUInt32s in (CDAB) Mid-Little Endian order - (4/4)
  • BytesToInt32s in (ABCD) Big Endian order - (1/4)
  • BytesToInt32s in (DCBA) Little Endian order - (2/4)
  • BytesToInt32s in (BADC) Mid-Big Endian order - (3/4)
  • BytesToInt32s in (CDAB) Mid-Little Endian order - (4/4)
• Bytes to 32-bit float array tests
  • BytesToFloat32s in (ABCD) Big Endian order - (1/4)
  • BytesToFloat32s in (DCBA) Little Endian order - (2/4)
  • BytesToFloat32s in (BADC) Mid-Big Endian order - (3/4)
  • BytesToFloat32s in (CDAB) Mid-Little Endian order - (4/4)
• Bytes/registers utility tests
  • BitStringToUInt8s test
  • BitStringToUInt8s test - left comma
  • BitStringToUInt8s test - right comma
  • BitStringToUInt8s test - left, right comma
  • RegistersToBytes test
  • BytesToHexString test
  • DecimalStringToRegisters test
  • DecimalStringToRegisters test - left comma
  • DecimalStringToRegisters test - right comma
  • DecimalStringToRegisters test - left, right comma
  • HexStringToRegisters test
  • HexStringToRegisters test - wrong length
  • LinearScalingRegisters test
  • LinearScalingRegisters test - (0,0,0,0)
  • LinearScalingRegisters test - reverse

Types

Upstream structure test

• One-off modbus tcp struct tests
  • mbtcp.once.read request test
  • mbtcp.once.read response test
• get/set modbus tcp timeout struct tests
  • mbtcp.timeout.read request test
  • mbtcp.timeout.read response test
  • mbtcp.timeout.update request test
  • mbtcp.timeout.update response test
  • mbtcp.once.write request test
  • mbtcp.once.write response test

Downstream structure test

• modbus tcp downstreamstruct tests
  • read request test
  • single read response test
  • multiple read response test
  • single write request test
  • multiple write request test
  • set timeout request test
  • get timeout response test

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UML

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License

MIT