Implemented new datasources (modbus,scpi)
This commit is contained in:
Martino Ferrari
@@ -0,0 +1,75 @@
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package scpi
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import "github.com/uopi/uopi/internal/datasource"
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// Config is the [datasource.scpi] section. Each instrument is polled
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// independently over its own TCP socket.
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type Config struct {
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Enabled bool `toml:"enabled"`
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// PollIntervalMs is the default polling period for channels that do not
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// override it. Zero → 1000 ms.
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PollIntervalMs int `toml:"poll_interval_ms"`
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Instruments []Instrument `toml:"instruments"`
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}
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// Instrument is one SCPI device reachable over a raw TCP socket. Address is
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// "host:port"; the conventional SCPI-raw port 5025 is appended if absent.
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type Instrument struct {
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Name string `toml:"name"`
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// Transport selects the link type. "raw" (default) is line-based SCPI over
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// TCP. Reserved: "vxi11" (not yet implemented).
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Transport string `toml:"transport"`
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Address string `toml:"address"`
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TimeoutMs int `toml:"timeout_ms"`
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// Terminator is appended to every command. Empty → "\n".
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Terminator string `toml:"terminator"`
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Channels []Channel `toml:"channels"`
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}
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// Channel maps a SCPI query/command pair onto a signal named
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// "instrument:channel".
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type Channel struct {
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Name string `toml:"name"`
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// Query is the SCPI command whose response is the channel value,
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// e.g. "MEAS:VOLT?". Required.
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Query string `toml:"query"`
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// WriteCmd is a printf-style template used by Write; "%v" is replaced with
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// the value, e.g. "VOLT %v". Empty → channel is read-only.
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WriteCmd string `toml:"write_cmd"`
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// Type is the value type: "float" (default), "string", "int", or "bool".
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Type string `toml:"type"`
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Unit string `toml:"unit"`
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Min float64 `toml:"min"`
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Max float64 `toml:"max"`
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PollIntervalMs int `toml:"poll_interval_ms"`
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Description string `toml:"description"`
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}
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func (c Channel) dataType() datasource.DataType {
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switch c.Type {
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case "string":
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return datasource.TypeString
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case "int":
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return datasource.TypeInt64
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case "bool":
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return datasource.TypeBool
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default:
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return datasource.TypeFloat64
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}
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}
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func (c Channel) writable() bool { return c.WriteCmd != "" }
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func (c Channel) metadata(instrument string) datasource.Metadata {
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return datasource.Metadata{
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Name: instrument + ":" + c.Name,
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Type: c.dataType(),
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Unit: c.Unit,
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Description: c.Description,
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DisplayLow: c.Min,
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DisplayHigh: c.Max,
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DriveLow: c.Min,
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DriveHigh: c.Max,
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Writable: c.writable(),
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}
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}
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@@ -0,0 +1,237 @@
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// Package scpi implements a SCPI instrument data source. Each configured
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// instrument is reached over a raw TCP socket (line-based SCPI, the "SCPI raw" /
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// port 5025 convention); a VXI-11 transport is reserved for later. Channels are
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// exposed as signals named "instrument:channel" and polled at a configurable
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// interval. Channels with a write_cmd template accept Write.
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package scpi
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import (
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"context"
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"fmt"
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"strconv"
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"strings"
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"time"
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"github.com/uopi/uopi/internal/datasource"
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)
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const defaultPollInterval = time.Second
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type instrumentConn struct {
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inst Instrument
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tr transport
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}
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// Scpi is a datasource.DataSource backed by one or more SCPI instruments.
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type Scpi struct {
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pollInterval time.Duration
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instruments map[string]*instrumentConn
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signals map[string]signalRef // "instrument:channel" → ref
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}
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type signalRef struct {
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instrument string
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ch Channel
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}
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// New builds a SCPI source from config. It does not dial; connections are
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// established lazily on first poll/write.
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func New(cfg Config) (*Scpi, error) {
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poll := time.Duration(cfg.PollIntervalMs) * time.Millisecond
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if poll <= 0 {
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poll = defaultPollInterval
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}
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s := &Scpi{
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pollInterval: poll,
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instruments: make(map[string]*instrumentConn),
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signals: make(map[string]signalRef),
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}
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for _, inst := range cfg.Instruments {
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if inst.Name == "" || inst.Address == "" {
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return nil, fmt.Errorf("scpi: instrument needs name and address")
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}
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if _, dup := s.instruments[inst.Name]; dup {
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return nil, fmt.Errorf("scpi: duplicate instrument %q", inst.Name)
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}
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tr, err := newTransport(inst)
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if err != nil {
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return nil, err
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}
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ic := &instrumentConn{inst: inst, tr: tr}
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for _, ch := range inst.Channels {
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if ch.Name == "" || ch.Query == "" {
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return nil, fmt.Errorf("scpi: instrument %q channel needs name and query", inst.Name)
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}
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key := inst.Name + ":" + ch.Name
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if _, dup := s.signals[key]; dup {
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return nil, fmt.Errorf("scpi: instrument %q duplicate channel %q", inst.Name, ch.Name)
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}
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s.signals[key] = signalRef{instrument: inst.Name, ch: ch}
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}
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s.instruments[inst.Name] = ic
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}
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return s, nil
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}
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// newTransport selects the transport implementation for an instrument.
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func newTransport(inst Instrument) (transport, error) {
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addr := inst.Address
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switch strings.ToLower(inst.Transport) {
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case "", "raw":
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if !strings.Contains(addr, ":") {
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addr += ":5025"
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}
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return newRawSocket(addr, time.Duration(inst.TimeoutMs)*time.Millisecond, inst.Terminator), nil
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case "vxi11":
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return nil, fmt.Errorf("scpi: vxi11 transport not yet implemented")
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default:
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return nil, fmt.Errorf("scpi: unknown transport %q", inst.Transport)
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}
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}
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// Name implements datasource.DataSource.
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func (s *Scpi) Name() string { return "scpi" }
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// Connect is a no-op; connections are dialled lazily per instrument.
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func (s *Scpi) Connect(_ context.Context) error { return nil }
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// ListSignals returns metadata for every configured channel.
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func (s *Scpi) ListSignals(_ context.Context) ([]datasource.Metadata, error) {
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out := make([]datasource.Metadata, 0, len(s.signals))
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for _, ref := range s.signals {
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out = append(out, ref.ch.metadata(ref.instrument))
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}
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return out, nil
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}
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// GetMetadata returns metadata for one signal.
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func (s *Scpi) GetMetadata(_ context.Context, signal string) (datasource.Metadata, error) {
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ref, ok := s.signals[signal]
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if !ok {
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return datasource.Metadata{}, datasource.ErrNotFound
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}
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return ref.ch.metadata(ref.instrument), nil
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}
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// readSignal performs one synchronous query of a channel.
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func (s *Scpi) readSignal(ref signalRef) (datasource.Value, error) {
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ic := s.instruments[ref.instrument]
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resp, err := ic.tr.query(ref.ch.Query)
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if err != nil {
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return datasource.Value{}, err
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}
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data, err := parseValue(ref.ch.dataType(), resp)
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if err != nil {
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return datasource.Value{}, err
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}
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return datasource.Value{Timestamp: time.Now(), Data: data, Quality: datasource.QualityGood}, nil
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}
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// Subscribe polls the channel at its configured interval (falling back to the
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// source default) and pushes values into ch. A query error emits QualityBad and
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// polling continues.
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func (s *Scpi) Subscribe(ctx context.Context, signal string, ch chan<- datasource.Value) (datasource.CancelFunc, error) {
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ref, ok := s.signals[signal]
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if !ok {
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return nil, datasource.ErrNotFound
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}
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interval := s.pollInterval
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if ref.ch.PollIntervalMs > 0 {
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interval = time.Duration(ref.ch.PollIntervalMs) * time.Millisecond
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}
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ctx, cancel := context.WithCancel(ctx)
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go func() {
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ticker := time.NewTicker(interval)
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defer ticker.Stop()
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emit := func() {
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v, err := s.readSignal(ref)
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if err != nil {
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v = datasource.Value{Timestamp: time.Now(), Quality: datasource.QualityBad}
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}
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select {
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case ch <- v:
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case <-ctx.Done():
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}
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}
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emit()
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for {
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select {
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case <-ticker.C:
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emit()
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case <-ctx.Done():
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return
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}
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}
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}()
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return datasource.CancelFunc(cancel), nil
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}
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// Write sends the channel's write_cmd template with the value substituted.
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func (s *Scpi) Write(_ context.Context, signal string, value any) error {
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ref, ok := s.signals[signal]
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if !ok {
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return datasource.ErrNotFound
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}
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if !ref.ch.writable() {
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return datasource.ErrNotWritable
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}
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ic := s.instruments[ref.instrument]
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cmd := formatWrite(ref.ch.WriteCmd, value)
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return ic.tr.write(cmd)
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}
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// History is unavailable for SCPI instruments.
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func (s *Scpi) History(_ context.Context, _ string, _, _ time.Time, _ int) ([]datasource.Value, error) {
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return nil, datasource.ErrHistoryUnavailable
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}
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// Close tears down every instrument connection.
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func (s *Scpi) Close() {
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for _, ic := range s.instruments {
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ic.tr.close()
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}
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}
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// formatWrite substitutes value into the write template. A "%" in the template
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// is treated as a printf verb; otherwise the value is appended after a space.
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func formatWrite(tmpl string, value any) string {
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if strings.Contains(tmpl, "%") {
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return fmt.Sprintf(tmpl, value)
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}
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return fmt.Sprintf("%s %v", tmpl, value)
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}
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// parseValue converts a raw SCPI response string into the channel's data type.
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func parseValue(t datasource.DataType, resp string) (any, error) {
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resp = strings.TrimSpace(resp)
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switch t {
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case datasource.TypeString:
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return resp, nil
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case datasource.TypeInt64:
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// Accept "12", "12.0", or scientific notation by going through float.
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f, err := strconv.ParseFloat(resp, 64)
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if err != nil {
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return nil, fmt.Errorf("scpi: parse int %q: %w", resp, err)
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}
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return int64(f), nil
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case datasource.TypeBool:
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switch strings.ToUpper(resp) {
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case "1", "ON", "TRUE":
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return true, nil
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case "0", "OFF", "FALSE":
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return false, nil
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}
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f, err := strconv.ParseFloat(resp, 64)
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if err != nil {
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return nil, fmt.Errorf("scpi: parse bool %q: %w", resp, err)
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}
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return f != 0, nil
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default:
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f, err := strconv.ParseFloat(resp, 64)
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if err != nil {
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return nil, fmt.Errorf("scpi: parse float %q: %w", resp, err)
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}
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return f, nil
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}
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}
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@@ -0,0 +1,267 @@
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package scpi
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import (
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"bufio"
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"context"
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"net"
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"strings"
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"sync"
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"testing"
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"time"
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"github.com/uopi/uopi/internal/datasource"
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)
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// mockInstrument is an in-process line-based SCPI server. It answers queries
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// from a fixed table and records commands that produce no response (writes).
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type mockInstrument struct {
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ln net.Listener
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mu sync.Mutex
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answers map[string]string // query → response
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writes []string
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}
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func newMockInstrument(t *testing.T) *mockInstrument {
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t.Helper()
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ln, err := net.Listen("tcp", "127.0.0.1:0")
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if err != nil {
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t.Fatalf("listen: %v", err)
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}
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m := &mockInstrument{ln: ln, answers: map[string]string{}}
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go m.serve()
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t.Cleanup(func() { ln.Close() })
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return m
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}
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func (m *mockInstrument) addr() string { return m.ln.Addr().String() }
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func (m *mockInstrument) setAnswer(q, a string) {
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m.mu.Lock()
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m.answers[q] = a
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m.mu.Unlock()
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}
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func (m *mockInstrument) writeLog() []string {
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m.mu.Lock()
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defer m.mu.Unlock()
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return append([]string(nil), m.writes...)
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}
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func (m *mockInstrument) serve() {
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for {
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conn, err := m.ln.Accept()
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if err != nil {
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return
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}
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go m.handle(conn)
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}
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}
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func (m *mockInstrument) handle(conn net.Conn) {
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defer conn.Close()
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br := bufio.NewReader(conn)
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for {
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line, err := br.ReadString('\n')
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if err != nil {
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return
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}
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cmd := strings.TrimRight(line, "\r\n")
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m.mu.Lock()
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if strings.HasSuffix(cmd, "?") {
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resp, ok := m.answers[cmd]
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if !ok {
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resp = "0"
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}
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m.mu.Unlock()
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conn.Write([]byte(resp + "\n"))
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continue
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}
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m.writes = append(m.writes, cmd)
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m.mu.Unlock()
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}
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}
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func testCfg(addr string) Config {
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return Config{
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Enabled: true,
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PollIntervalMs: 20,
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Instruments: []Instrument{{
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Name: "dmm",
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Address: addr,
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Channels: []Channel{
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{Name: "volt", Query: "MEAS:VOLT?", WriteCmd: "VOLT %v", Type: "float", Unit: "V"},
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{Name: "id", Query: "*IDN?", Type: "string"},
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{Name: "n", Query: "COUNT?", Type: "int"},
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{Name: "out", Query: "OUTP?", WriteCmd: "OUTP", Type: "bool"},
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},
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}},
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}
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}
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func TestQueryTypes(t *testing.T) {
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srv := newMockInstrument(t)
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srv.setAnswer("MEAS:VOLT?", "12.34")
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srv.setAnswer("*IDN?", "ACME,DMM,1,2.0")
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srv.setAnswer("COUNT?", "7")
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srv.setAnswer("OUTP?", "ON")
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s, err := New(testCfg(srv.addr()))
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if err != nil {
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t.Fatalf("New: %v", err)
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}
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defer s.Close()
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v, err := s.readSignal(s.signals["dmm:volt"])
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if err != nil {
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t.Fatalf("read volt: %v", err)
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}
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if f, ok := v.Data.(float64); !ok || f < 12.33 || f > 12.35 {
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t.Errorf("volt = %v (%T), want 12.34", v.Data, v.Data)
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}
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id, _ := s.readSignal(s.signals["dmm:id"])
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if id.Data != "ACME,DMM,1,2.0" {
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t.Errorf("id = %v", id.Data)
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}
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n, _ := s.readSignal(s.signals["dmm:n"])
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if iv, ok := n.Data.(int64); !ok || iv != 7 {
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t.Errorf("n = %v (%T), want 7", n.Data, n.Data)
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}
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out, _ := s.readSignal(s.signals["dmm:out"])
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if b, ok := out.Data.(bool); !ok || !b {
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t.Errorf("out = %v, want true", out.Data)
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}
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}
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func TestWrite(t *testing.T) {
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srv := newMockInstrument(t)
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s, _ := New(testCfg(srv.addr()))
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defer s.Close()
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ctx := context.Background()
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if err := s.Write(ctx, "dmm:volt", 3.3); err != nil {
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t.Fatalf("write volt: %v", err)
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}
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// bool write uses a template with no verb → "OUTP <val>".
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if err := s.Write(ctx, "dmm:out", true); err != nil {
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t.Fatalf("write out: %v", err)
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}
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// Give the server a moment to record both writes.
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deadline := time.Now().Add(time.Second)
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for time.Now().Before(deadline) {
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if len(srv.writeLog()) >= 2 {
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break
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}
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time.Sleep(5 * time.Millisecond)
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}
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got := srv.writeLog()
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if len(got) != 2 || got[0] != "VOLT 3.3" || got[1] != "OUTP true" {
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t.Errorf("writes = %v, want [VOLT 3.3, OUTP true]", got)
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}
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}
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func TestWriteErrors(t *testing.T) {
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srv := newMockInstrument(t)
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s, _ := New(testCfg(srv.addr()))
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defer s.Close()
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||||
ctx := context.Background()
|
||||
|
||||
if err := s.Write(ctx, "dmm:missing", 1); err != datasource.ErrNotFound {
|
||||
t.Errorf("missing = %v, want ErrNotFound", err)
|
||||
}
|
||||
if err := s.Write(ctx, "dmm:id", 1); err != datasource.ErrNotWritable {
|
||||
t.Errorf("read-only = %v, want ErrNotWritable", err)
|
||||
}
|
||||
}
|
||||
|
||||
func TestSubscribe(t *testing.T) {
|
||||
srv := newMockInstrument(t)
|
||||
srv.setAnswer("MEAS:VOLT?", "5.0")
|
||||
s, _ := New(testCfg(srv.addr()))
|
||||
defer s.Close()
|
||||
|
||||
ctx, cancel := context.WithCancel(context.Background())
|
||||
defer cancel()
|
||||
ch := make(chan datasource.Value, 4)
|
||||
stop, err := s.Subscribe(ctx, "dmm:volt", ch)
|
||||
if err != nil {
|
||||
t.Fatalf("subscribe: %v", err)
|
||||
}
|
||||
defer stop()
|
||||
|
||||
select {
|
||||
case v := <-ch:
|
||||
if v.Quality != datasource.QualityGood {
|
||||
t.Errorf("quality = %v", v.Quality)
|
||||
}
|
||||
if f, ok := v.Data.(float64); !ok || f != 5.0 {
|
||||
t.Errorf("value = %v, want 5.0", v.Data)
|
||||
}
|
||||
case <-time.After(2 * time.Second):
|
||||
t.Fatal("timed out")
|
||||
}
|
||||
}
|
||||
|
||||
func TestSubscribeBadQuality(t *testing.T) {
|
||||
cfg := testCfg("127.0.0.1:1") // refused
|
||||
s, _ := New(cfg)
|
||||
defer s.Close()
|
||||
|
||||
ctx, cancel := context.WithCancel(context.Background())
|
||||
defer cancel()
|
||||
ch := make(chan datasource.Value, 1)
|
||||
stop, _ := s.Subscribe(ctx, "dmm:volt", ch)
|
||||
defer stop()
|
||||
|
||||
select {
|
||||
case v := <-ch:
|
||||
if v.Quality != datasource.QualityBad {
|
||||
t.Errorf("quality = %v, want bad", v.Quality)
|
||||
}
|
||||
case <-time.After(2 * time.Second):
|
||||
t.Fatal("timed out")
|
||||
}
|
||||
}
|
||||
|
||||
func TestValidation(t *testing.T) {
|
||||
if _, err := New(Config{Instruments: []Instrument{{Name: "", Address: "x"}}}); err == nil {
|
||||
t.Error("want error for missing name")
|
||||
}
|
||||
if _, err := New(Config{Instruments: []Instrument{{Name: "a", Address: "x"}, {Name: "a", Address: "y"}}}); err == nil {
|
||||
t.Error("want error for duplicate instrument")
|
||||
}
|
||||
if _, err := New(Config{Instruments: []Instrument{{Name: "a", Address: "x", Transport: "vxi11"}}}); err == nil {
|
||||
t.Error("want error for unimplemented vxi11 transport")
|
||||
}
|
||||
if _, err := New(Config{Instruments: []Instrument{{Name: "a", Address: "x", Transport: "bogus"}}}); err == nil {
|
||||
t.Error("want error for unknown transport")
|
||||
}
|
||||
if _, err := New(Config{Instruments: []Instrument{{Name: "a", Address: "x", Channels: []Channel{{Name: "c"}}}}}); err == nil {
|
||||
t.Error("want error for channel without query")
|
||||
}
|
||||
}
|
||||
|
||||
func TestFormatWrite(t *testing.T) {
|
||||
if got := formatWrite("VOLT %v", 3.3); got != "VOLT 3.3" {
|
||||
t.Errorf("verb template = %q", got)
|
||||
}
|
||||
if got := formatWrite("OUTP", true); got != "OUTP true" {
|
||||
t.Errorf("plain template = %q", got)
|
||||
}
|
||||
}
|
||||
|
||||
func TestParseValue(t *testing.T) {
|
||||
if v, _ := parseValue(datasource.TypeBool, "OFF"); v != false {
|
||||
t.Errorf("OFF = %v, want false", v)
|
||||
}
|
||||
if v, _ := parseValue(datasource.TypeBool, "2.0"); v != true {
|
||||
t.Errorf("2.0 bool = %v, want true", v)
|
||||
}
|
||||
if _, err := parseValue(datasource.TypeFloat64, "notnum"); err == nil {
|
||||
t.Error("want parse error for non-numeric float")
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,107 @@
|
||||
package scpi
|
||||
|
||||
import (
|
||||
"bufio"
|
||||
"fmt"
|
||||
"net"
|
||||
"strings"
|
||||
"sync"
|
||||
"time"
|
||||
)
|
||||
|
||||
// transport is the request/response channel to an instrument. The raw-socket
|
||||
// implementation below speaks line-oriented SCPI over TCP (the common
|
||||
// "SCPI raw" / port 5025 convention). The interface is kept narrow so a VXI-11
|
||||
// (ONC-RPC) transport can be added later without touching the data source.
|
||||
type transport interface {
|
||||
// query sends cmd and returns the instrument's single-line response.
|
||||
query(cmd string) (string, error)
|
||||
// write sends cmd and does not wait for a response.
|
||||
write(cmd string) error
|
||||
close()
|
||||
}
|
||||
|
||||
// rawSocket is a line-based SCPI transport over a single TCP connection. The
|
||||
// connection is dialled lazily and dropped on any I/O error so the next call
|
||||
// reconnects. Calls are serialised by mu because SCPI is request/response.
|
||||
type rawSocket struct {
|
||||
addr string
|
||||
timeout time.Duration
|
||||
terminator string
|
||||
|
||||
mu sync.Mutex
|
||||
conn net.Conn
|
||||
br *bufio.Reader
|
||||
}
|
||||
|
||||
func newRawSocket(addr string, timeout time.Duration, terminator string) *rawSocket {
|
||||
if timeout <= 0 {
|
||||
timeout = 3 * time.Second
|
||||
}
|
||||
if terminator == "" {
|
||||
terminator = "\n"
|
||||
}
|
||||
return &rawSocket{addr: addr, timeout: timeout, terminator: terminator}
|
||||
}
|
||||
|
||||
func (s *rawSocket) dialLocked() error {
|
||||
if s.conn != nil {
|
||||
return nil
|
||||
}
|
||||
conn, err := net.DialTimeout("tcp", s.addr, s.timeout)
|
||||
if err != nil {
|
||||
return fmt.Errorf("scpi: dial %s: %w", s.addr, err)
|
||||
}
|
||||
s.conn = conn
|
||||
s.br = bufio.NewReader(conn)
|
||||
return nil
|
||||
}
|
||||
|
||||
func (s *rawSocket) closeLocked() {
|
||||
if s.conn != nil {
|
||||
_ = s.conn.Close()
|
||||
s.conn = nil
|
||||
s.br = nil
|
||||
}
|
||||
}
|
||||
|
||||
func (s *rawSocket) close() {
|
||||
s.mu.Lock()
|
||||
s.closeLocked()
|
||||
s.mu.Unlock()
|
||||
}
|
||||
|
||||
func (s *rawSocket) sendLocked(cmd string) error {
|
||||
_ = s.conn.SetDeadline(time.Now().Add(s.timeout))
|
||||
if _, err := s.conn.Write([]byte(cmd + s.terminator)); err != nil {
|
||||
s.closeLocked()
|
||||
return fmt.Errorf("scpi: write: %w", err)
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func (s *rawSocket) write(cmd string) error {
|
||||
s.mu.Lock()
|
||||
defer s.mu.Unlock()
|
||||
if err := s.dialLocked(); err != nil {
|
||||
return err
|
||||
}
|
||||
return s.sendLocked(cmd)
|
||||
}
|
||||
|
||||
func (s *rawSocket) query(cmd string) (string, error) {
|
||||
s.mu.Lock()
|
||||
defer s.mu.Unlock()
|
||||
if err := s.dialLocked(); err != nil {
|
||||
return "", err
|
||||
}
|
||||
if err := s.sendLocked(cmd); err != nil {
|
||||
return "", err
|
||||
}
|
||||
line, err := s.br.ReadString('\n')
|
||||
if err != nil {
|
||||
s.closeLocked()
|
||||
return "", fmt.Errorf("scpi: read: %w", err)
|
||||
}
|
||||
return strings.TrimRight(line, "\r\n"), nil
|
||||
}
|
||||
Reference in New Issue
Block a user