github.com/m3db/m3@v1.5.0/src/cmd/services/m3comparator/main/parser/parser.go (about)

     1  // Copyright (c) 2020 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package parser
    22  
    23  import (
    24  	"encoding/json"
    25  	"fmt"
    26  	"sort"
    27  	"strconv"
    28  	"strings"
    29  	"time"
    30  )
    31  
    32  // Series is a flat JSON serializable representation of the series.
    33  type Series struct {
    34  	id string
    35  
    36  	Start      time.Time  `json:"start"`
    37  	End        time.Time  `json:"end"`
    38  	Tags       Tags       `json:"tags"`
    39  	Datapoints Datapoints `json:"datapoints"`
    40  }
    41  
    42  // Tag is a simple JSON serializable representation of a tag.
    43  type Tag [2]string
    44  
    45  // NewTag creates a new tag with a given name and value.
    46  func NewTag(name, value string) Tag {
    47  	return Tag{name, value}
    48  }
    49  
    50  // Name returns the tag name.
    51  func (t Tag) Name() string {
    52  	return t[0]
    53  }
    54  
    55  // Value returns the tag value.
    56  func (t Tag) Value() string {
    57  	return t[1]
    58  }
    59  
    60  // Tags is a simple JSON serializable representation of tags.
    61  type Tags []Tag
    62  
    63  // Get returns a list of tag values with the given name.
    64  func (t Tags) Get(name string) []string {
    65  	// NB: this is almost always going to be 0
    66  	values := make([]string, 0, 2)
    67  	// NB: This list isn't expected to get very long so it uses array lookup.
    68  	// If this is a problem in the future, `Tags` be converted to a map.
    69  	for _, t := range t {
    70  		if t.Name() == name {
    71  			values = append(values, t.Value())
    72  		}
    73  	}
    74  
    75  	return values
    76  }
    77  
    78  // Datapoints is a JSON serializeable list of values for the series.
    79  type Datapoints []Datapoint
    80  
    81  // Datapoint is a JSON serializeable datapoint for the series.
    82  type Datapoint struct {
    83  	Value     Value     `json:"val"`
    84  	Timestamp time.Time `json:"ts"`
    85  }
    86  
    87  // Value is a JSON serizlizable float64 that allows NaNs.
    88  type Value float64
    89  
    90  // MarshalJSON returns state as the JSON encoding of a Value.
    91  func (v Value) MarshalJSON() ([]byte, error) {
    92  	return json.Marshal(fmt.Sprintf("%g", float64(v)))
    93  }
    94  
    95  // UnmarshalJSON unmarshals JSON-encoded data into a Value.
    96  func (v *Value) UnmarshalJSON(data []byte) error {
    97  	var str string
    98  	err := json.Unmarshal(data, &str)
    99  	if err != nil {
   100  		return err
   101  	}
   102  
   103  	f, err := strconv.ParseFloat(str, 64)
   104  	if err != nil {
   105  		return err
   106  	}
   107  
   108  	*v = Value(f)
   109  	return nil
   110  }
   111  
   112  // IDOrGenID gets the ID for this result.
   113  func (r *Series) IDOrGenID() string {
   114  	if len(r.id) == 0 {
   115  		tags := make(sort.StringSlice, len(r.Tags))
   116  		for _, v := range r.Tags {
   117  			tags = append(tags, fmt.Sprintf("%s:%s,", v[0], v[1]))
   118  		}
   119  
   120  		sort.Sort(tags)
   121  		var sb strings.Builder
   122  		for _, t := range tags {
   123  			sb.WriteString(t)
   124  		}
   125  
   126  		r.id = sb.String()
   127  	}
   128  
   129  	return r.id
   130  }