netdata/netdata

// SPDX-License-Identifier: GPL-3.0-or-later

package module

import (
    "errors"
    "fmt"
    "strings"
    "unicode"
)

type (
    ChartType string
    DimAlgo   string
)

const (
    // Line chart type.
    Line ChartType = "line"
    // Area chart type.
    Area ChartType = "area"
    // Stacked chart type.
    Stacked ChartType = "stacked"

    // Absolute dimension algorithm.
    // The value is to drawn as-is (interpolated to second boundary).
    Absolute DimAlgo = "absolute"
    // Incremental dimension algorithm.
    // The value increases over time, the difference from the last value is presented in the chart,
    // the server interpolates the value and calculates a per second figure.
    Incremental DimAlgo = "incremental"
    // PercentOfAbsolute dimension algorithm.
    // The percent of this value compared to the total of all dimensions.
    PercentOfAbsolute DimAlgo = "percentage-of-absolute-row"
    // PercentOfIncremental dimension algorithm.
    // The percent of this value compared to the incremental total of all dimensions
    PercentOfIncremental DimAlgo = "percentage-of-incremental-row"
)

const (
    // Not documented.
    // https://github.com/netdata/netdata/blob/cc2586de697702f86a3c34e60e23652dd4ddcb42/database/rrd.h#L204

    LabelSourceAuto = 1 << 0
    LabelSourceConf = 1 << 1
    LabelSourceK8s  = 1 << 2
)

func (d DimAlgo) String() string {
    switch d {
    case Absolute, Incremental, PercentOfAbsolute, PercentOfIncremental:
        return string(d)
    }
    return string(Absolute)
}

func (c ChartType) String() string {
    switch c {
    case Line, Area, Stacked:
        return string(c)
    }
    return string(Line)
}

type (
    // Charts is a collection of Charts.
    Charts []*Chart

    // Opts represents chart options.
    Opts struct {
        Obsolete   bool
        Detail     bool
        StoreFirst bool
        Hidden     bool
    }

    // Chart represents a chart.
    // For the full description please visit https://docs.netdata.cloud/collectors/plugins.d/#chart
    Chart struct {
        // typeID is the unique identification of the chart, if not specified,
        // the orchestrator will use job full name + chart ID as typeID (default behaviour).
        typ string
        id  string

        OverModule string
        IDSep      bool
        ID         string
        OverID     string
        Title      string
        Units      string
        Fam        string
        Ctx        string
        Type       ChartType
        Priority   int
        Opts

        Labels []Label
        Dims   Dims
        Vars   Vars

        Retries int

        remove bool
        // created flag is used to indicate whether the chart needs to be created by the orchestrator.
        created bool
        // updated flag is used to indicate whether the chart was updated on last data collection interval.
        updated bool

        // ignore flag is used to indicate that the chart shouldn't be sent to the netdata plugins.d
        ignore bool
    }

    Label struct {
        Key    string
        Value  string
        Source int
    }

    // DimOpts represents dimension options.
    DimOpts struct {
        Obsolete   bool
        Hidden     bool
        NoReset    bool
        NoOverflow bool
    }

    // Dim represents a chart dimension.
    // For detailed description please visit https://docs.netdata.cloud/collectors/plugins.d/#dimension.
    Dim struct {
        ID   string
        Name string
        Algo DimAlgo
        Mul  int
        Div  int
        DimOpts

        remove bool
    }

    // Var represents a chart variable.
    // For detailed description please visit https://docs.netdata.cloud/collectors/plugins.d/#variable
    Var struct {
        ID    string
        Name  string
        Value int64
    }

    // Dims is a collection of dims.
    Dims []*Dim
    // Vars is a collection of vars.
    Vars []*Var
)

func (o Opts) String() string {
    var b strings.Builder
    if o.Detail {
        b.WriteString(" detail")
    }
    if o.Hidden {
        b.WriteString(" hidden")
    }
    if o.Obsolete {
        b.WriteString(" obsolete")
    }
    if o.StoreFirst {
        b.WriteString(" store_first")
    }

    if len(b.String()) == 0 {
        return ""
    }
    return b.String()[1:]
}

func (o DimOpts) String() string {
    var b strings.Builder
    if o.Hidden {
        b.WriteString(" hidden")
    }
    if o.NoOverflow {
        b.WriteString(" nooverflow")
    }
    if o.NoReset {
        b.WriteString(" noreset")
    }
    if o.Obsolete {
        b.WriteString(" obsolete")
    }

    if len(b.String()) == 0 {
        return ""
    }
    return b.String()[1:]
}

// Add adds (appends) a variable number of Charts.
func (c *Charts) Add(charts ...*Chart) error {
    for _, chart := range charts {
        err := checkChart(chart)
        if err != nil {
            return fmt.Errorf("error on adding chart '%s' : %s", chart.ID, err)
        }
        if chart := c.Get(chart.ID); chart != nil && !chart.remove {
            return fmt.Errorf("error on adding chart : '%s' is already in charts", chart.ID)
        }
        *c = append(*c, chart)
    }

    return nil
}

// Get returns the chart by ID.
func (c Charts) Get(chartID string) *Chart {
    idx := c.index(chartID)
    if idx == -1 {
        return nil
    }
    return c[idx]
}

// Has returns true if ChartsFunc contain the chart with the given ID, false otherwise.
func (c Charts) Has(chartID string) bool {
    return c.index(chartID) != -1
}

// Remove removes the chart from Charts by ID.
// Avoid to use it in runtime.
func (c *Charts) Remove(chartID string) error {
    idx := c.index(chartID)
    if idx == -1 {
        return fmt.Errorf("error on removing chart : '%s' is not in charts", chartID)
    }
    copy((*c)[idx:], (*c)[idx+1:])
    (*c)[len(*c)-1] = nil
    *c = (*c)[:len(*c)-1]
    return nil
}

// Copy returns a deep copy of ChartsFunc.
func (c Charts) Copy() *Charts {
    charts := Charts{}
    for idx := range c {
        charts = append(charts, c[idx].Copy())
    }
    return &charts
}

func (c Charts) index(chartID string) int {
    for idx := range c {
        if c[idx].ID == chartID {
            return idx
        }
    }
    return -1
}

// MarkNotCreated changes 'created' chart flag to false.
// Use it to add dimension in runtime.
func (c *Chart) MarkNotCreated() {
    c.created = false
}

// MarkRemove sets 'remove' flag and Obsolete option to true.
// Use it to remove chart in runtime.
func (c *Chart) MarkRemove() {
    c.Obsolete = true
    c.remove = true
}

// MarkDimRemove sets 'remove' flag, Obsolete and optionally Hidden options to true.
// Use it to remove dimension in runtime.
func (c *Chart) MarkDimRemove(dimID string, hide bool) error {
    if !c.HasDim(dimID) {
        return fmt.Errorf("chart '%s' has no '%s' dimension", c.ID, dimID)
    }
    dim := c.GetDim(dimID)
    dim.Obsolete = true
    if hide {
        dim.Hidden = true
    }
    dim.remove = true
    return nil
}

// AddDim adds new dimension to the chart dimensions.
func (c *Chart) AddDim(newDim *Dim) error {
    err := checkDim(newDim)
    if err != nil {
        return fmt.Errorf("error on adding dim to chart '%s' : %s", c.ID, err)
    }
    if c.HasDim(newDim.ID) {
        return fmt.Errorf("error on adding dim : '%s' is already in chart '%s' dims", newDim.ID, c.ID)
    }
    c.Dims = append(c.Dims, newDim)

    return nil
}

// AddVar adds new variable to the chart variables.
func (c *Chart) AddVar(newVar *Var) error {
    err := checkVar(newVar)
    if err != nil {
        return fmt.Errorf("error on adding var to chart '%s' : %s", c.ID, err)
    }
    if c.indexVar(newVar.ID) != -1 {
        return fmt.Errorf("error on adding var : '%s' is already in chart '%s' vars", newVar.ID, c.ID)
    }
    c.Vars = append(c.Vars, newVar)

    return nil
}

// GetDim returns dimension by ID.
func (c *Chart) GetDim(dimID string) *Dim {
    idx := c.indexDim(dimID)
    if idx == -1 {
        return nil
    }
    return c.Dims[idx]
}

// RemoveDim removes dimension by ID.
// Avoid to use it in runtime.
func (c *Chart) RemoveDim(dimID string) error {
    idx := c.indexDim(dimID)
    if idx == -1 {
        return fmt.Errorf("error on removing dim : '%s' isn't in chart '%s'", dimID, c.ID)
    }
    c.Dims = append(c.Dims[:idx], c.Dims[idx+1:]...)

    return nil
}

// HasDim returns true if the chart contains dimension with the given ID, false otherwise.
func (c Chart) HasDim(dimID string) bool {
    return c.indexDim(dimID) != -1
}

// Copy returns a deep copy of the chart.
func (c Chart) Copy() *Chart {
    chart := c
    chart.Dims = Dims{}
    chart.Vars = Vars{}

    for idx := range c.Dims {
        chart.Dims = append(chart.Dims, c.Dims[idx].copy())
    }
    for idx := range c.Vars {
        chart.Vars = append(chart.Vars, c.Vars[idx].copy())
    }

    return &chart
}

func (c Chart) indexDim(dimID string) int {
    for idx := range c.Dims {
        if c.Dims[idx].ID == dimID {
            return idx
        }
    }
    return -1
}

func (c Chart) indexVar(varID string) int {
    for idx := range c.Vars {
        if c.Vars[idx].ID == varID {
            return idx
        }
    }
    return -1
}

func (d Dim) copy() *Dim {
    return &d
}

func (v Var) copy() *Var {
    return &v
}

func checkCharts(charts ...*Chart) error {
    for _, chart := range charts {
        err := checkChart(chart)
        if err != nil {
            return fmt.Errorf("chart '%s' : %v", chart.ID, err)
        }
    }
    return nil
}

func checkChart(chart *Chart) error {
    if chart.ID == "" {
        return errors.New("empty ID")
    }

    if chart.Title == "" {
        return errors.New("empty Title")
    }

    if chart.Units == "" {
        return errors.New("empty Units")
    }

    if id := checkID(chart.ID); id != -1 {
        return fmt.Errorf("unacceptable symbol in ID : '%c'", id)
    }

    set := make(map[string]bool)

    for _, d := range chart.Dims {
        err := checkDim(d)
        if err != nil {
            return err
        }
        if set[d.ID] {
            return fmt.Errorf("duplicate dim '%s'", d.ID)
        }
        set[d.ID] = true
    }

    set = make(map[string]bool)

    for _, v := range chart.Vars {
        if err := checkVar(v); err != nil {
            return err
        }
        if set[v.ID] {
            return fmt.Errorf("duplicate var '%s'", v.ID)
        }
        set[v.ID] = true
    }
    return nil
}

func checkDim(d *Dim) error {
    if d.ID == "" {
        return errors.New("empty dim ID")
    }
    if id := checkID(d.ID); id != -1 {
        return fmt.Errorf("unacceptable symbol in dim ID '%s' : '%c'", d.ID, id)
    }
    return nil
}

func checkVar(v *Var) error {
    if v.ID == "" {
        return errors.New("empty var ID")
    }
    if id := checkID(v.ID); id != -1 {
        return fmt.Errorf("unacceptable symbol in var ID '%s' : '%c'", v.ID, id)
    }
    return nil
}

func checkID(id string) int {
    for _, r := range id {
        if unicode.IsSpace(r) {
            return int(r)
        }
    }
    return -1
}