Add CLI with root command that uses embedded dataset (#14)

* Add main.go as entrypoint for CLI

* Add CLI with root command and embed Ember 2021 data

* Add unit test coverage

* Add data section to README for Ember

README.md

@@ -13,3 +13,8 @@ We call this the fuel mix, and this fuel mix can impact on the carbon intensity
 ## Move your code through time and space
 
 Because the fuel mix will be different depending when and where you run your code, you can influence the carbon intensity of the code you write by moving it through time and space - either by making it run when the grid is greener, or making it run where it's greener, like a CDN running on green power.
+
+## Data
+
+Carbon intensity data from [Ember](https://ember-climate.org/), in accordance of their licensing - [CC-BY-SA 4.0](https://ember-climate.org/creative-commons/
+)

errors.go → api/errors.go

@@ -1,4 +1,4 @@
-package gridintensity
+package api
 
 import "errors"
 

multi.go → api/multi.go

@@ -1,4 +1,4 @@
-package gridintensity
+package api
 
 import (
 	"context"

multi_test.go → api/multi_test.go

@@ -1,11 +1,11 @@
-package gridintensity_test
+package api_test
 
 import (
 	"context"
 	"errors"
 	"testing"
 
-	gridintensity "github.com/thegreenwebfoundation/grid-intensity-go"
+	gridintensity "github.com/thegreenwebfoundation/grid-intensity-go/api"
 )
 
 var responseTable = map[string]float64{

provider.go → api/provider.go

@@ -1,4 +1,4 @@
-package gridintensity
+package api
 
 import (
 	"context"

carbonintensity/client.go

@@ -6,7 +6,7 @@ import (
 	"net/http"
 	"time"
 
-	gridintensity "github.com/thegreenwebfoundation/grid-intensity-go"
+	gridintensity "github.com/thegreenwebfoundation/grid-intensity-go/api"
 )
 
 type ApiOption func(*ApiClient) error

cmd/root.go

@@ -0,0 +1,79 @@
+package cmd
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"os"
+
+	"github.com/Xuanwo/go-locale"
+	"github.com/spf13/cobra"
+
+	"github.com/thegreenwebfoundation/grid-intensity-go/data"
+)
+
+const (
+	countryCode = "country-code"
+)
+
+// rootCmd represents the base command when called without any subcommands
+var rootCmd = &cobra.Command{
+	Use:   "grid-intensity",
+	Short: "Get carbon intensity data for electricity grids",
+	Long: `A tool for getting the carbon intensity data for electricity grids.
+
+This can be used to make your sofware carbon aware so it runs at times when the
+grid is greener or at locations where carbon intensity is lower.
+
+	grid-intensity --country-code ARG
+	grid-intensity -c BOL`,
+
+	Run: func(cmd *cobra.Command, args []string) {
+		country, err := cmd.Flags().GetString(countryCode)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		err = getGridIntensityForCountry(country)
+		if err != nil {
+			log.Fatal(err)
+		}
+	},
+}
+
+func Execute() {
+	err := rootCmd.Execute()
+	if err != nil {
+		os.Exit(1)
+	}
+}
+
+func init() {
+	rootCmd.Flags().StringP(countryCode, "c", "", "Country code in ISO 3 character format")
+}
+
+func getGridIntensityForCountry(countryCode string) error {
+	if countryCode == "" {
+		// No country code provided so try to detect it from the user's locale.
+		tag, err := locale.Detect()
+		if err != nil {
+			return err
+		}
+
+		region, _ := tag.Region()
+		countryCode = region.ISO3()
+	}
+
+	result, err := data.GetGridIntensityForCountry(countryCode)
+	if err != nil {
+		return err
+	}
+
+	bytes, err := json.MarshalIndent(result, "", "\t")
+	if err != nil {
+		return err
+	}
+
+	fmt.Println(string(bytes))
+	return nil
+}

data/co2-intensities-ember-2021.csv

@@ -0,0 +1,87 @@
+country_code,country_or_region,year,latest_year,emissions_intensity_gco2_per_kwh
+,Africa,2021,2021,489.26
+ARG,Argentina,2021,2021,365.292
+ARM,Armenia,2021,2021,206.522
+,Asia,2021,2021,543.57
+AUS,Australia,2021,2021,526.876
+AUT,Austria,2021,2021,145.083
+AZE,Azerbaijan,2021,2021,536.585
+BGD,Bangladesh,2021,2021,559.606
+BLR,Belarus,2021,2021,472.727
+BEL,Belgium,2021,2021,156.063
+BOL,Bolivia,2021,2021,311.475
+BIH,Bosnia Herzegovina,2021,2021,470.982
+BRA,Brazil,2021,2021,144.677
+BGR,Bulgaria,2021,2021,364.136
+BDI,Burundi,2021,2021,275.862
+CAN,Canada,2021,2021,123.859
+CHL,Chile,2021,2021,395.565
+CHN,China,2021,2021,549.288
+CRI,Costa Rica,2021,2021,30.903
+HRV,Croatia,2021,2021,212.161
+CYP,Cyprus,2021,2021,601.19
+CZE,Czechia,2021,2021,401.272
+DNK,Denmark,2021,2021,240.419
+ECU,Ecuador,2021,2021,132.964
+EGY,Egypt,2021,2021,470.879
+SLV,El Salvador,2021,2021,180.87
+EST,Estonia,2021,2021,488.529
+,EU,2021,2021,261.43
+,Europe,2021,2021,277.64
+FIN,Finland,2021,2021,152.651
+FRA,France,2021,2021,67.781
+,G20,2021,2021,445.9
+,G7,2021,2021,338.04
+GEO,Georgia,2021,2021,105.685
+DEU,Germany,2021,2021,363.982
+GRC,Greece,2021,2021,363.388
+HUN,Hungary,2021,2021,236.271
+IND,India,2021,2021,632.656
+IRL,Ireland,2021,2021,361.274
+ITA,Italy,2021,2021,340.937
+JPN,Japan,2021,2021,460.647
+KAZ,Kazakhstan,2021,2021,656.097
+KEN,Kenya,2021,2021,104.0
+,Latin America and Caribbean,2021,2021,261.51
+LVA,Latvia,2021,2021,226.351
+LTU,Lithuania,2021,2021,247.475
+LUX,Luxembourg,2021,2021,183.824
+MLT,Malta,2021,2021,452.055
+MEX,Mexico,2021,2021,391.582
+MDA,Moldova,2021,2021,642.512
+MNG,Mongolia,2021,2021,725.26
+MNE,Montenegro,2021,2021,335.958
+NLD,Netherlands,2021,2021,386.189
+,North America,2021,2021,345.38
+MKD,North Macedonia,2021,2021,444.191
+NOR,Norway,2021,2021,26.131
+,Oceania,2021,2021,479.98
+,OECD,2021,2021,338.24
+PAK,Pakistan,2021,2021,363.065
+PER,Peru,2021,2021,241.492
+PHL,Philippines (the),2021,2021,579.689
+POL,Poland,2021,2021,657.138
+PRT,Portugal,2021,2021,222.632
+ROU,Romania,2021,2021,255.718
+RUS,Russian Federation (the),2021,2021,355.431
+SAU,Saudi Arabia,2021,2021,568.967
+SEN,Senegal,2021,2021,540.098
+SRB,Serbia,2021,2021,549.083
+SGP,Singapore,2021,2021,488.21
+SVK,Slovakia,2021,2021,173.854
+SVN,Slovenia,2021,2021,241.956
+ZAF,South Africa,2021,2021,706.991
+KOR,South Korea,2021,2021,442.389
+ESP,Spain,2021,2021,193.737
+SWE,Sweden,2021,2021,43.9
+CHE,Switzerland,2021,2021,58.952
+TWN,Taiwan (Province of China),2021,2021,565.629
+TJK,Tajikistan,2021,2021,72.823
+THA,Thailand,2021,2021,503.034
+TUN,Tunisia,2021,2021,470.848
+TUR,Turkey,2021,2021,432.293
+UKR,Ukraine,2021,2021,240.28
+GBR,United Kingdom,2021,2021,268.255
+USA,United States of America,2021,2021,378.625
+VNM,Viet Nam,2021,2021,491.192
+,World,2021,2021,442.3

data/data.go

@@ -0,0 +1,58 @@
+package data
+
+import (
+	"bytes"
+	_ "embed"
+	"encoding/csv"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+type GridIntensity struct {
+	CountryCode                  string  `json:"country_code"`
+	CountryOrRegion              string  `json:"country_or_region"`
+	Year                         int     `json:"year"`
+	LatestYear                   int     `json:"latest_year"`
+	EmissionsIntensityGCO2PerKWH float64 `json:"emissions_intensity_gco2_per_kwh"`
+}
+
+//go:embed co2-intensities-ember-2021.csv
+var data []byte
+
+func GetGridIntensityForCountry(countryCode string) (*GridIntensity, error) {
+	reader := bytes.NewReader(data)
+	rows, err := csv.NewReader(reader).ReadAll()
+	if err != nil {
+		return nil, err
+	}
+
+	for _, row := range rows {
+		if strings.EqualFold(row[0], countryCode) {
+			year, err := strconv.Atoi(row[2])
+			if err != nil {
+				return nil, err
+			}
+
+			latestYear, err := strconv.Atoi(row[3])
+			if err != nil {
+				return nil, err
+			}
+
+			intensity, err := strconv.ParseFloat(row[4], 64)
+			if err != nil {
+				return nil, err
+			}
+
+			return &GridIntensity{
+				CountryCode:                  row[0],
+				CountryOrRegion:              row[1],
+				Year:                         year,
+				LatestYear:                   latestYear,
+				EmissionsIntensityGCO2PerKWH: intensity,
+			}, nil
+		}
+	}
+
+	return nil, fmt.Errorf("country code %q not found", countryCode)
+}

data/data_test.go

@@ -0,0 +1,62 @@
+package data
+
+import (
+	"reflect"
+	"testing"
+)
+
+func Test_GetGridIntensityForCountry(t *testing.T) {
+	tests := []struct {
+		name        string
+		countryCode string
+		result      *GridIntensity
+		expectedErr string
+	}{
+		{
+			name:        "country exists",
+			countryCode: "ESP",
+			result: &GridIntensity{
+				CountryCode:                  "ESP",
+				CountryOrRegion:              "Spain",
+				Year:                         2021,
+				LatestYear:                   2021,
+				EmissionsIntensityGCO2PerKWH: 193.737,
+			},
+		},
+		{
+			name:        "lower case country code",
+			countryCode: "gbr",
+			result: &GridIntensity{
+				CountryCode:                  "GBR",
+				CountryOrRegion:              "United Kingdom",
+				Year:                         2021,
+				LatestYear:                   2021,
+				EmissionsIntensityGCO2PerKWH: 268.255,
+			},
+		},
+		{
+			name:        "invalid country code",
+			countryCode: "AAA",
+			expectedErr: "country code \"AAA\" not found",
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			result, err := GetGridIntensityForCountry(tc.countryCode)
+			switch {
+			case err != nil && tc.expectedErr == "":
+				t.Fatalf("error == %#v want nil", err)
+			case err == nil && tc.expectedErr != "":
+				t.Fatalf("error == nil want non-nil")
+			}
+
+			if !reflect.DeepEqual(tc.result, result) {
+				t.Fatalf("expected %#v got %#v", tc.result, result)
+			}
+			if tc.expectedErr != "" && tc.expectedErr != err.Error() {
+				t.Fatalf("expected error %q got %q", tc.expectedErr, err.Error())
+			}
+		})
+	}
+}

electricitymap/client.go

@@ -7,7 +7,7 @@ import (
 	"net/http"
 	"time"
 
-	gridintensity "github.com/thegreenwebfoundation/grid-intensity-go"
+	gridintensity "github.com/thegreenwebfoundation/grid-intensity-go/api"
 )
 
 type ApiOption func(*ApiClient) error

electricitymap/client_test.go

@@ -9,7 +9,7 @@ import (
 	"testing"
 	"time"
 
-	gridintensity "github.com/thegreenwebfoundation/grid-intensity-go"
+	gridintensity "github.com/thegreenwebfoundation/grid-intensity-go/api"
 	"github.com/thegreenwebfoundation/grid-intensity-go/electricitymap"
 )
 

examples/electricitymap/main.go

@@ -5,7 +5,7 @@ import (
 	"log"
 	"os"
 
-	gridintensity "github.com/thegreenwebfoundation/grid-intensity-go"
+	gridintensity "github.com/thegreenwebfoundation/grid-intensity-go/api"
 	"github.com/thegreenwebfoundation/grid-intensity-go/electricitymap"
 )
 

go.mod

@@ -1,3 +1,15 @@
 module github.com/thegreenwebfoundation/grid-intensity-go
 
-go 1.15
+go 1.18
+
+require (
+	github.com/Xuanwo/go-locale v1.1.0
+	github.com/spf13/cobra v1.4.0
+)
+
+require (
+	github.com/inconshreveable/mousetrap v1.0.0 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
+	golang.org/x/sys v0.0.0-20211023085530-d6a326fbbf70 // indirect
+	golang.org/x/text v0.3.7 // indirect
+)