instance

Documentation

Index

• type Config
• type Datum
• type Instance
  • func New(config Config) (*Instance, error)
  • func (i *Instance) GetLabelValues(ctx context.Context, searchTerm string) ([]string, error)
  • func (i *Instance) GetMetrics(ctx context.Context, queries []Query, resolution string, ...) (*Metrics, error)
  • func (i *Instance) GetTableData(ctx context.Context, queries []Query, timeEnd int64) (map[string]map[string]string, error)
  • func (i *Instance) GetVariable(ctx context.Context, label, query, queryType string, timeStart, timeEnd int64) ([]string, error)
• type Metric
• type Metrics
• type Query

Types

type Config

type Config struct {
	Name        string `json:"name"`
	DisplayName string `json:"displayName"`
	Description string `json:"description"`
	Home        bool   `json:"home"`
	Address     string `json:"address"`
	Username    string `json:"username"`
	Password    string `json:"password"`
	Token       string `json:"token"`
}

Config is the structure of the configuration for a single Prometheus instance.

type Datum

type Datum struct {
	X int64    `json:"x"`
	Y *float64 `json:"y"`
}

Datum is the structure of a single data point of a metric. The y value must be a pointer, because when the value is NaN we can not set the value (NaN in the JSON representation will throw an error). For that NaN values will always be null.

type Instance

type Instance struct {
	Name string
	// contains filtered or unexported fields
}

Instance represents a single Prometheus instance, which can be added via the configuration file.

func New

func New(config Config) (*Instance, error)

New returns a new Prometheus instance for the given configuration.

func (*Instance) GetLabelValues

func (i *Instance) GetLabelValues(ctx context.Context, searchTerm string) ([]string, error)

GetLabelValues returns all label values for a configured Prometheus instance. These labels are used to show the user a list of suggestions for his entered query. The returned label values from the Prometheus API are cached for one hour.

func (*Instance) GetMetrics

func (i *Instance) GetMetrics(ctx context.Context, queries []Query, resolution string, timeStart, timeEnd int64) (*Metrics, error)

GetMetrics returns all metrics for all given queries. For each given query we have to make one call to the Prometheus API. Then we have to loop through the returned time series and transform them into a format, which can be processed by out React UI.

func (*Instance) GetTableData

func (i *Instance) GetTableData(ctx context.Context, queries []Query, timeEnd int64) (map[string]map[string]string, error)

GetTableData returns the data, when the user selected the table view for the Prometheus plugin. To get the data we are running all prodived queries and join the results by the value for a label of a query. The value for a query is added as value-N column. We are also adding all other labels as fields to a single row.

func (*Instance) GetVariable

func (i *Instance) GetVariable(ctx context.Context, label, query, queryType string, timeStart, timeEnd int64) ([]string, error)

GetVariable returns all values for a label from the given query. For that we have to retrive the label sets from the Prometheus instance and so that we can add the values for the specified label to the values slice.

type Metric

type Metric struct {
	ID    string  `json:"id"`
	Label string  `json:"label"`
	Min   float64 `json:"min"`
	Max   float64 `json:"max"`
	Avg   float64 `json:"avg"`
	Data  []Datum `json:"data"`
}

Metric is the response format for a single metric. Each metric must have an ID and label. We also add the min, max and average for the returned data.

type Metrics

type Metrics struct {
	StartTime int64    `json:"startTime"`
	EndTime   int64    `json:"endTime"`
	Min       float64  `json:"min"`
	Max       float64  `json:"max"`
	Metrics   []Metric `json:"metrics"`
}

Metrics is the structure for the returned metrics from the Prometheus metrics API endpoint. It contains a list of metrics, the start and end time for the query and the min and max value accross all time series.

type Query

type Query struct {
	Query string `json:"query"`
	Label string `json:"label"`
}

Query is the structure of a query. Each query consists of the PromQL query and an optional label, which can be displayed in the legend of a chart.