huge refactoring

app/config/config.go

@@ -0,0 +1,170 @@
+package config
+
+import (
+	"io/ioutil"
+	"text/template"
+
+	"github.com/gulien/gotenberg/app/logger"
+
+	"github.com/satori/go.uuid"
+	"github.com/sirupsen/logrus"
+	"gopkg.in/yaml.v2"
+)
+
+type (
+	AppConfig struct {
+		Port string
+		Logs struct {
+			Level     logrus.Level
+			Formatter logrus.Formatter
+		}
+		CommandsConfig *CommandsConfig
+	}
+
+	CommandsConfig struct {
+		HTML   *CommandConfig
+		Office *CommandConfig
+		Merge  *CommandConfig
+	}
+
+	CommandConfig struct {
+		Timeout  int
+		Template *template.Template
+	}
+)
+
+func NewAppConfig() (*AppConfig, error) {
+	fileConfig, err := loadFileConfig()
+	if err != nil {
+		logger.Error(err)
+		return nil, &fileConfigError{}
+	}
+
+	c := &AppConfig{}
+	c.Port = fileConfig.Port
+	c.Logs.Level = getLoggingLevelFromFileConfig(fileConfig)
+	c.Logs.Formatter = getLoggingFormatterFromFileConfig(fileConfig)
+
+	if c.Logs.Level == 999 {
+		return nil, &wrongLoggingLevelError{}
+	}
+
+	if c.Logs.Formatter == nil {
+		return nil, &wrongLoggingFormatError{}
+	}
+
+	c.CommandsConfig = &CommandsConfig{}
+	c.CommandsConfig.HTML = &CommandConfig{}
+	c.CommandsConfig.Office = &CommandConfig{}
+	c.CommandsConfig.Merge = &CommandConfig{}
+	c.CommandsConfig.HTML.Timeout = fileConfig.Commands.HTML.Timeout
+	c.CommandsConfig.Office.Timeout = fileConfig.Commands.Office.Timeout
+	c.CommandsConfig.Merge.Timeout = fileConfig.Commands.Merge.Timeout
+
+	tmplHTML, err := getCommandTemplate(fileConfig.Commands.HTML.Template)
+	if err != nil {
+		logger.Error(err)
+		return nil, &wrongHTMLCommandTemplate{}
+	}
+
+	tmplOffice, err := getCommandTemplate(fileConfig.Commands.Office.Template)
+	if err != nil {
+		logger.Error(err)
+		return nil, &wrongOfficeCommandTemplate{}
+	}
+
+	tmplMerge, err := getCommandTemplate(fileConfig.Commands.Merge.Template)
+	if err != nil {
+		logger.Error(err)
+		return nil, &wrongMergeCommandTemplate{}
+	}
+
+	c.CommandsConfig.HTML.Template = tmplHTML
+	c.CommandsConfig.Office.Template = tmplOffice
+	c.CommandsConfig.Merge.Template = tmplMerge
+
+	return c, nil
+}
+
+type fileConfig struct {
+	Port string `yaml:"port"`
+	Logs struct {
+		Level  string `yaml:"level"`
+		Format string `yaml:"format"`
+	} `yaml:"logs"`
+	Commands struct {
+		HTML struct {
+			Timeout  int
+			Template string
+		} `yaml:"html"`
+		Office struct {
+			Timeout  int    `yaml:"timeout"`
+			Template string `yaml:"template"`
+		} `yaml:"office"`
+		Merge struct {
+			Timeout  int    `yaml:"timeout"`
+			Template string `yaml:"template"`
+		} `yaml:"merge"`
+	} `yaml:"commands"`
+}
+
+// configurationFilePath is our default configuration file to parse.
+const configurationFilePath = "gotenberg.yml"
+
+func loadFileConfig() (*fileConfig, error) {
+	c := &fileConfig{}
+
+	data, err := ioutil.ReadFile(configurationFilePath)
+	if err != nil {
+		logger.Error(err)
+		return nil, &readFileError{}
+	}
+
+	if err := yaml.Unmarshal(data, &c); err != nil {
+		logger.Error(err)
+		return nil, &unmarshalError{}
+	}
+
+	return c, nil
+}
+
+var levels = map[string]logrus.Level{
+	"DEBUG": logrus.DebugLevel,
+	"INFO":  logrus.InfoLevel,
+	"WARN":  logrus.WarnLevel,
+	"ERROR": logrus.ErrorLevel,
+	"FATAL": logrus.FatalLevel,
+	"PANIC": logrus.PanicLevel,
+}
+
+func getLoggingLevelFromFileConfig(c *fileConfig) logrus.Level {
+	l, ok := levels[c.Logs.Level]
+	if !ok {
+		return 999
+	}
+
+	return l
+}
+
+var formatters = map[string]logrus.Formatter{
+	"text": &logrus.TextFormatter{},
+	"json": &logrus.JSONFormatter{},
+}
+
+func getLoggingFormatterFromFileConfig(c *fileConfig) logrus.Formatter {
+	f, ok := formatters[c.Logs.Format]
+	if !ok {
+		return nil
+	}
+
+	return f
+}
+
+func getCommandTemplate(command string) (*template.Template, error) {
+	t, err := template.New(uuid.NewV4().String()).Parse(command)
+	if err != nil {
+		return nil, err
+	}
+
+	return t, nil
+}

app/config/errors.go

@@ -0,0 +1,49 @@
+package config
+
+type fileConfigError struct{}
+
+func (e *fileConfigError) Error() string {
+	return "An error occured while trying to load the configuration file"
+}
+
+type wrongLoggingLevelError struct{}
+
+func (e *wrongLoggingLevelError) Error() string {
+	return "Accepted values for logging level: DEBUG, INFO, WARN, ERROR, FATAL, PANIC"
+}
+
+type wrongLoggingFormatError struct{}
+
+func (e *wrongLoggingFormatError) Error() string {
+	return "Accepted value for logging format: text, json"
+}
+
+type wrongHTMLCommandTemplate struct{}
+
+func (e *wrongHTMLCommandTemplate) Error() string {
+	return "An error occured while trying to parse the HTML command's template"
+}
+
+type wrongOfficeCommandTemplate struct{}
+
+func (e *wrongOfficeCommandTemplate) Error() string {
+	return "An error occured while trying to parse the Office command's template"
+}
+
+type wrongMergeCommandTemplate struct{}
+
+func (e *wrongMergeCommandTemplate) Error() string {
+	return "An error occured while trying to parse the merge command's template"
+}
+
+type readFileError struct{}
+
+func (e *readFileError) Error() string {
+	return "An error occured while trying to read the configuration file"
+}
+
+type unmarshalError struct{}
+
+func (e *unmarshalError) Error() string {
+	return "An error occured while trying to decode the configuration file as YAML"
+}