feat: Add notification templates (#2)

Signed-off-by: Julien Riou <julien@riou.xyz>

README.md

@@ -78,6 +78,33 @@ Reference:
     * `token`: token of the Telegram bot
     * `chat-id` (optional if `channel-name` is present): chat identifier to send Telegram notifications
     * `channel-name` (optional if `chat-id` is present): channel name to send Telegram notifications
+* `notification-templates` (optional): path to [template](https://pkg.go.dev/text/template) files for each notification type
+    * `balance` (optional): path to template file to format balance notifications
+    * `payment` (optional): path to template file to format payment notifications
+    * `block` (optional): path to template file to format block notifications
+    * `offline-worker` (optional): path to template file to format offline worker notifications
+
+## Templating
+
+Notifications can be customized with [templating](https://pkg.go.dev/text/template).
+
+The following **functions** are available to templates:
+* `upper(str string)`: convert string to upper case
+* `lower(str string)`: convert string to lower case
+* `convertCurrency(coin string, value int64)`: convert the smallest unit of a coin to a human readable unit
+* `convertAction(coin string)`: return "Farmed" word for Chia coin or "Mined" for other coins
+* `formatBlockURL(coin string, hash string)`: return the URL on the explorer website of the coin of the block identified by its hash
+* `formatTransactionURL(coin string, hash string)`: return the URL on the explorer website of the coin of the transaction identified by its hash
+
+The following **data** is available to templates:
+* balance: `.Miner`
+* payment: `.Miner`, `.Payment`
+* block: `.Pool`, `.Block`
+* offline-worker: `.Worker`
+
+Default templates are available in the [templates](templates) directory.
+
+Custom template files can be used with the `notification-templates` settings (see _Configuration_ section).
 
 ## Usage
 

config.go

@@ -8,12 +8,13 @@ import (
 
 // Config to receive settings from the configuration file
 type Config struct {
-	DatabaseFile   string         `yaml:"database-file"`
+	DatabaseFile          string                      `yaml:"database-file"`
-	MaxBlocks      int            `yaml:"max-blocks"`
+	MaxBlocks             int                         `yaml:"max-blocks"`
-	MaxPayments    int            `yaml:"max-payments"`
+	MaxPayments           int                         `yaml:"max-payments"`
-	Pools          []PoolConfig   `yaml:"pools"`
+	Pools                 []PoolConfig                `yaml:"pools"`
-	Miners         []MinerConfig  `yaml:"miners"`
+	Miners                []MinerConfig               `yaml:"miners"`
-	TelegramConfig TelegramConfig `yaml:"telegram"`
+	TelegramConfig        TelegramConfig              `yaml:"telegram"`
+	NotificationTemplates NotificationTemplatesConfig `yaml:"notification-templates"`
 }
 
 // PoolConfig to store Pool configuration
@@ -37,6 +38,14 @@ type TelegramConfig struct {
 	ChannelName string `yaml:"channel-name"`
 }
 
+// NotificationTemplatesConfig to store notifications templates configuration
+type NotificationTemplatesConfig struct {
+	Balance       string `yaml:"balance"`
+	Payment       string `yaml:"payment"`
+	Block         string `yaml:"block"`
+	OfflineWorker string `yaml:"offline-worker"`
+}
+
 // NewConfig creates a Config with default values
 func NewConfig() *Config {
 	return &Config{

flexassistant.yaml.example

@@ -20,3 +20,8 @@ telegram:
   chat-id: 000000000
   channel-name: MyTelegramChannel
   token: 0000000000000000000000000000000000000000000000
+notification-templates:
+  balance: balance.tmpl
+  block: block.tmpl
+  offline-worker; offline-worker.tmpl
+  payment: payment.tmpl

go.mod

@@ -4,7 +4,6 @@ go 1.16
 
 require (
 	github.com/go-telegram-bot-api/telegram-bot-api/v5 v5.0.0-rc1
-	github.com/leekchan/accounting v1.0.0 // indirect
 	github.com/sirupsen/logrus v1.8.1
 	gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b
 	gorm.io/driver/sqlite v1.1.5

go.sum

@@ -1,5 +1,3 @@
-github.com/cockroachdb/apd v1.1.0 h1:3LFP3629v+1aKXU5Q37mxmRxX/pIu1nijXydLShEq5I=
-github.com/cockroachdb/apd v1.1.0/go.mod h1:8Sl8LxpKi29FqWXR16WEFZRNSz3SoPzUzeMeY4+DwBQ=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/go-telegram-bot-api/telegram-bot-api/v5 v5.0.0-rc1 h1:Mr8jIV7wDfLw5Fw6BPupm0aduTFdLjhI3wFuIIZKvO4=
@@ -8,17 +6,10 @@ github.com/jinzhu/inflection v1.0.0 h1:K317FqzuhWc8YvSVlFMCCUb36O/S9MCKRDI7QkRKD
 github.com/jinzhu/inflection v1.0.0/go.mod h1:h+uFLlag+Qp1Va5pdKtLDYj+kHp5pxUVkryuEj+Srlc=
 github.com/jinzhu/now v1.1.2 h1:eVKgfIdy9b6zbWBMgFpfDPoAMifwSZagU9HmEU6zgiI=
 github.com/jinzhu/now v1.1.2/go.mod h1:d3SSVoowX0Lcu0IBviAWJpolVfI5UJVZZ7cO71lE/z8=
-github.com/leekchan/accounting v1.0.0 h1:+Wd7dJ//dFPa28rc1hjyy+qzCbXPMR91Fb6F1VGTQHg=
-github.com/leekchan/accounting v1.0.0/go.mod h1:3timm6YPhY3YDaGxl0q3eaflX0eoSx3FXn7ckHe4tO0=
-github.com/lib/pq v1.0.0/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
 github.com/mattn/go-sqlite3 v1.14.8 h1:gDp86IdQsN/xWjIEmr9MF6o9mpksUgh0fu+9ByFxzIU=
 github.com/mattn/go-sqlite3 v1.14.8/go.mod h1:NyWgC/yNuGj7Q9rpYnZvas74GogHl5/Z4A/KQRfk6bU=
-github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
-github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/shopspring/decimal v0.0.0-20180709203117-cd690d0c9e24 h1:pntxY8Ary0t43dCZ5dqY4YTJCObLY1kIXl0uzMv+7DE=
-github.com/shopspring/decimal v0.0.0-20180709203117-cd690d0c9e24/go.mod h1:M+9NzErvs504Cn4c5DxATwIqPbtswREoFCre64PpcG4=
 github.com/sirupsen/logrus v1.8.1 h1:dJKuHgqk1NNQlqoA6BTlM1Wf9DOH3NBjQyu0h9+AZZE=
 github.com/sirupsen/logrus v1.8.1/go.mod h1:yWOB1SBYBC5VeMP7gHvWumXLIWorT60ONWic61uBYv0=
 github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=

main.go

@@ -84,7 +84,7 @@ func main() {
 	client := NewFlexpoolClient()
 
 	// Notifications
-	notifier, err := NewTelegramNotifier(&config.TelegramConfig)
+	notifier, err := NewTelegramNotifier(&config.TelegramConfig, &config.NotificationTemplates)
 	if err != nil {
 		log.Fatalf("Could not create notifier: %v", err)
 	}

notification.go

@@ -1,15 +1,30 @@
 package main
 
 import (
+	"bytes"
+	"embed"
 	"fmt"
+	"os"
+	"path"
 	"strings"
-
+	"text/template"
-	"github.com/leekchan/accounting"
 
 	telegram "github.com/go-telegram-bot-api/telegram-bot-api/v5"
 	log "github.com/sirupsen/logrus"
 )
 
+//go:embed templates
+var templateFiles embed.FS
+
+// Attachment is used to attach objects to templates
+type Attachment struct {
+	Miner   Miner
+	Payment Payment
+	Pool    Pool
+	Block   Block
+	Worker  Worker
+}
+
 // Notifier interface to define how to send all kind of notifications
 type Notifier interface {
 	NotifyBalance(miner Miner, difference float64) error
@@ -21,13 +36,14 @@ type Notifier interface {
 // TelegramNotifier to send notifications using Telegram
 // Implements the Notifier interface
 type TelegramNotifier struct {
-	bot         *telegram.BotAPI
+	bot             *telegram.BotAPI
-	chatID      int64
+	chatID          int64
-	channelName string
+	channelName     string
+	templatesConfig *NotificationTemplatesConfig
 }
 
 // NewTelegramNotifier to create a TelegramNotifier
-func NewTelegramNotifier(config *TelegramConfig) (*TelegramNotifier, error) {
+func NewTelegramNotifier(config *TelegramConfig, templatesConfig *NotificationTemplatesConfig) (*TelegramNotifier, error) {
 	bot, err := telegram.NewBotAPI(config.Token)
 	if err != nil {
 		return nil, err
@@ -35,9 +51,10 @@ func NewTelegramNotifier(config *TelegramConfig) (*TelegramNotifier, error) {
 	log.Debugf("Connected to Telegram as %s", bot.Self.UserName)
 
 	return &TelegramNotifier{
-		bot:         bot,
+		bot:             bot,
-		chatID:      config.ChatID,
+		chatID:          config.ChatID,
-		channelName: config.ChannelName,
+		channelName:     config.ChannelName,
+		templatesConfig: templatesConfig,
 	}, nil
 }
 
@@ -60,77 +77,103 @@ func (t *TelegramNotifier) sendMessage(message string) error {
 	return nil
 }
 
+// formatMessage to create a message with a template file name (either embeded or on disk)
+func (t *TelegramNotifier) formatMessage(templateFileName string, attachment interface{}) (message string, err error) {
+	// Deduce if template file is embeded or is a file on disk
+	embeded := true
+	if _, err = os.Stat(templateFileName); os.IsExist(err) {
+		embeded = false
+	}
+	// Reinitialize the error because it was only used for the test
+	err = nil
+
+	// Create template
+	templateName := path.Base(templateFileName)
+	templateFunctions := template.FuncMap{
+		"upper":                strings.ToUpper,
+		"lower":                strings.ToLower,
+		"convertCurrency":      ConvertCurrency,
+		"convertAction":        ConvertAction,
+		"formatBlockURL":       FormatBlockURL,
+		"formatTransactionURL": FormatTransactionURL,
+	}
+	tmpl := template.New(templateName).Funcs(templateFunctions)
+
+	// Parse template
+	if embeded {
+		log.Debugf("Parsing embeded template file %s", templateFileName)
+		tmpl, err = tmpl.ParseFS(templateFiles, templateFileName)
+	} else {
+		log.Debugf("Parsing template file %s", templateFileName)
+		tmpl, err = tmpl.ParseFiles(templateFileName)
+	}
+	if err != nil {
+		return "", fmt.Errorf("parse failed: %v", err)
+	}
+
+	// Execute template
+	var buffer bytes.Buffer
+	err = tmpl.Execute(&buffer, attachment)
+	if err != nil {
+		return "", fmt.Errorf("execute failed: %v", err)
+	}
+
+	// Extract and return the formatted message
+	message = buffer.String()
+	return message, nil
+}
+
 // NotifyBalance to format and send a notification when the unpaid balance has changed
 // Implements the Notifier interface
-func (t *TelegramNotifier) NotifyBalance(miner Miner) error {
+func (t *TelegramNotifier) NotifyBalance(miner Miner) (err error) {
-	ac := accounting.Accounting{
+	templateName := "templates/balance.tmpl"
-		Symbol:    strings.ToUpper(miner.Coin),
+	if t.templatesConfig.Balance != "" {
-		Precision: 6,
+		templateName = t.templatesConfig.Balance
-		Format:    "%v %s",
 	}
-	convertedBalance, err := ConvertCurrency(miner.Coin, miner.Balance)
+	message, err := t.formatMessage(templateName, Attachment{Miner: miner})
 	if err != nil {
 		return err
 	}
-	message := fmt.Sprintf("💰 *Balance* _%s_", ac.FormatMoney(convertedBalance))
 	return t.sendMessage(message)
 }
 
 // NotifyPayment to format and send a notification when a new payment has been detected
 // Implements the Notifier interface
 func (t *TelegramNotifier) NotifyPayment(miner Miner, payment Payment) error {
-	ac := accounting.Accounting{
+	templateName := "templates/payment.tmpl"
-		Symbol:    strings.ToUpper(miner.Coin),
+	if t.templatesConfig.Payment != "" {
-		Precision: 6,
+		templateName = t.templatesConfig.Payment
-		Format:    "%v %s",
 	}
-	convertedValue, err := ConvertCurrency(miner.Coin, payment.Value)
+	message, err := t.formatMessage(templateName, Attachment{Miner: miner, Payment: payment})
 	if err != nil {
 		return err
 	}
-
-	message := fmt.Sprintf("💵 *Payment* _%s_", ac.FormatMoney(convertedValue))
 	return t.sendMessage(message)
 }
 
 // NotifyBlock to format and send a notification when a new block has been detected
 // Implements the Notifier interface
 func (t *TelegramNotifier) NotifyBlock(pool Pool, block Block) error {
-	precision := 6
+	templateName := "templates/block.tmpl"
-	if pool.Coin == "xch" {
+	if t.templatesConfig.Block != "" {
-		precision = 2
+		templateName = t.templatesConfig.Block
 	}
-	ac := accounting.Accounting{
+	message, err := t.formatMessage(templateName, Attachment{Pool: pool, Block: block})
-		Symbol:    strings.ToUpper(pool.Coin),
-		Precision: precision,
-		Format:    "%v %s",
-	}
-
-	convertedValue, err := ConvertCurrency(pool.Coin, block.Reward)
 	if err != nil {
 		return err
 	}
-	verb, err := ConvertAction(pool.Coin)
-	if err != nil {
-		return err
-	}
-	url, err := FormatBlockURL(pool.Coin, block.Hash)
-	if err != nil {
-		return err
-	}
-
-	message := fmt.Sprintf("🎉 *%s* [#%d](%s) _%s_", verb, block.Number, url, ac.FormatMoney(convertedValue))
 	return t.sendMessage(message)
 }
 
 // NotifyOfflineWorker sends a message when a worker is online or offline
 func (t *TelegramNotifier) NotifyOfflineWorker(worker Worker) error {
-	stateIcon := "🟢"
+	templateName := "templates/offline-worker.tmpl"
-	stateMessage := "online"
+	if t.templatesConfig.OfflineWorker != "" {
-	if !worker.IsOnline {
+		templateName = t.templatesConfig.OfflineWorker
-		stateIcon = "🔴"
+	}
-		stateMessage = "offline"
+	message, err := t.formatMessage(templateName, Attachment{Worker: worker})
+	if err != nil {
+		return err
 	}
-	message := fmt.Sprintf("%s *Worker* _%s_ is %s", stateIcon, worker.Name, stateMessage)
 	return t.sendMessage(message)
 }

templates/balance.tmpl

@@ -0,0 +1 @@
+💰 *Balance* _{{ printf "%.6f" (convertCurrency .Miner.Coin .Miner.Balance) }} {{ upper .Miner.Coin }}_

templates/block.tmpl

@@ -0,0 +1,6 @@
+🎉 *{{ convertAction .Pool.Coin }}* [#{{ .Block.Number }}]({{ formatBlockURL .Pool.Coin .Block.Hash }}) _
+{{- if (eq .Pool.Coin "xch") -}}
+        {{ printf "%.2f" (convertCurrency .Pool.Coin .Block.Reward) }}
+    {{- else -}}
+        {{ printf "%.6f" (convertCurrency .Pool.Coin .Block.Reward) }}
+    {{- end }} {{ upper .Pool.Coin }}_

templates/offline-worker.tmpl

@@ -0,0 +1,5 @@
+{{ if .Worker.IsOnline -}}
+🟢 *Worker* _{{ .Worker.Name }}_ is online
+{{- else -}}
+🔴 *Worker* _{{ .Worker.Name }}_ is offline
+{{- end -}}

templates/payment.tmpl

@@ -0,0 +1 @@
+💵 *Payment* _{{ printf "%.6f" (convertCurrency .Miner.Coin .Payment.Value) }} {{ upper .Miner.Coin }}_