Changes for new version of esplora image (#62)

* changes for new version of esplora image

* add electrs port and esplora url env vars in compose yaml files

* wrap viper methods into Config type and use constants package

* add controller to interact with nigiri resources:
 * .env for docker-compose
 * docker daemon
 * json config file

* add use of constants and config packages and change start flag from --port to --env

* add package for global constants and variables

* add use of controller and constants packages instead of local methods and vars

* bump version

* use contants in logs command tests

cli/controller/env.go

@@ -0,0 +1,124 @@
+package controller
+
+import (
+	"bufio"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/vulpemventures/nigiri/cli/constants"
+)
+
+// Env implements functions for interacting with the environment file used by
+// docker-compose to dynamically set service ports and variables
+type Env struct{}
+
+func (e *Env) writeEnvForCompose(path, strJSON string) error {
+	var env map[string]interface{}
+	err := json.Unmarshal([]byte(strJSON), &env)
+	if err != nil {
+		return constants.ErrMalformedJSON
+	}
+
+	fileContent := ""
+	for chain, services := range env["ports"].(map[string]interface{}) {
+		for k, v := range services.(map[string]interface{}) {
+			fileContent += fmt.Sprintf("%s_%s_PORT=%d\n", strings.ToUpper(chain), strings.ToUpper(k), int(v.(float64)))
+		}
+	}
+	for hostname, url := range env["urls"].(map[string]interface{}) {
+		fileContent += fmt.Sprintf("%s_URL=%s\n", strings.ToUpper(hostname), url.(string))
+	}
+
+	return ioutil.WriteFile(path, []byte(fileContent), os.ModePerm)
+}
+
+func (e *Env) readEnvForCompose(path string) (map[string]interface{}, error) {
+	file, err := os.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	scanner := bufio.NewScanner(file)
+	scanner.Split(bufio.ScanLines)
+
+	ports := map[string]map[string]int{
+		"bitcoin": map[string]int{},
+		"liquid":  map[string]int{},
+	}
+	urls := map[string]string{}
+	// Each line is in the format PREFIX_SERVICE_NAME_SUFFIX=value
+	// PREFIX is either 'BITCOIN' or 'LIQUID', while SUFFIX is either 'PORT' or 'URL'
+	for scanner.Scan() {
+		line := scanner.Text()
+		splitLine := strings.Split(line, "=")
+		key := splitLine[0]
+
+		if strings.Contains(key, "PORT") {
+			value, _ := strconv.Atoi(splitLine[1])
+			chain := "bitcoin"
+			if strings.HasPrefix(key, strings.ToUpper("liquid")) {
+				chain = "liquid"
+			}
+			prefix := strings.ToUpper(fmt.Sprintf("%s_", chain))
+			suffix := "_PORT"
+			trimmedKey := strings.ToLower(
+				strings.TrimSuffix(strings.TrimPrefix(key, prefix), suffix),
+			)
+			ports[chain][trimmedKey] = value
+		} else {
+			// Here the prefix is not trimmed
+			value := splitLine[1]
+			suffix := "_URL"
+			trimmedKey := strings.ToLower(strings.TrimSuffix(key, suffix))
+			urls[trimmedKey] = value
+		}
+	}
+
+	return map[string]interface{}{"ports": ports, "urls": urls}, nil
+}
+
+func (e *Env) load(path string) []string {
+	content, _ := ioutil.ReadFile(path)
+	lines := strings.Split(string(content), "\n")
+	env := os.Environ()
+	for _, line := range lines {
+		if line != "" {
+			env = append(env, line)
+		}
+	}
+
+	return env
+}
+
+type envPortsData struct {
+	Node       int `json:"node,omitempty"`
+	Esplora    int `json:"esplora,omitempty"`
+	Electrs    int `json:"electrs,omitempty"`
+	ElectrsRPC int `json:"electrs_rpc,omitempty"`
+	Chopsticks int `json:"chopsticks,omitempty"`
+}
+type envPorts struct {
+	Bitcoin *envPortsData `json:"bitcoin,omitempty"`
+	Liquid  *envPortsData `json:"liquid,omitempty"`
+}
+type envUrls struct {
+	BitcoinEsplora string `json:"bitcoin_esplora,omitempty"`
+	LiquidEsplora  string `json:"liquid_esplora,omitempty"`
+}
+type envJSON struct {
+	Ports *envPorts `json:"ports,omitempty"`
+	Urls  *envUrls  `json:"urls,omitempty"`
+}
+
+func (e envJSON) copy() envJSON {
+	var v envJSON
+	bytes, _ := json.Marshal(e)
+	json.Unmarshal(bytes, &v)
+
+	return v
+}