huge refactoring

internal/pkg/xassert/xassert.go

@@ -0,0 +1,185 @@
+package xassert
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+
+	"github.com/thecodingmachine/gotenberg/internal/pkg/xerror"
+)
+
+/*
+String applies validation on a string.
+
+If string is empty or validation fails,
+returns the default value.
+
+The key is used to identify the value.
+*/
+func String(key, value, defaultValue string, rules ...RuleString) (string, error) {
+	const op string = "xassert.String"
+	result := defaultValue
+	if value != "" {
+		result = value
+	}
+	for _, rule := range rules {
+		rule.with(key, result)
+		if err := rule.validate(); err != nil {
+			return defaultValue, xerror.New(op, err)
+		}
+	}
+	return result, nil
+}
+
+/*
+StringFromEnv returns the value of given environment
+variable or the default value if not found or
+validation fails.
+*/
+func StringFromEnv(envVar, defaultValue string, rules ...RuleString) (string, error) {
+	const op string = "xassert.StringFromEnv"
+	value := os.Getenv(envVar)
+	result, err := String(envVar, value, defaultValue, rules...)
+	if err != nil {
+		return result, xerror.New(op, err)
+	}
+	return result, nil
+}
+
+/*
+Int64 tries to convert a string to an int64.
+
+If string is empty, conversion or validation fails,
+returns the default value.
+
+The key is used to identify the value.
+*/
+func Int64(key, value string, defaultValue int64, rules ...RuleInt64) (int64, error) {
+	const op string = "xassert.Int64"
+	result := defaultValue
+	if value != "" {
+		parsedValue, err := strconv.ParseInt(value, 10, 64)
+		if err != nil {
+			return defaultValue, xerror.Invalid(
+				op,
+				fmt.Sprintf("'%s' is not an integer, got '%s'", key, value),
+				err,
+			)
+		}
+		result = parsedValue
+	}
+	for _, rule := range rules {
+		rule.with(key, result)
+		if err := rule.validate(); err != nil {
+			return defaultValue, xerror.New(op, err)
+		}
+	}
+	return result, nil
+}
+
+/*
+Int64FromEnv returns the int64 representation of the
+value of given environment variable.
+
+If not found, empty, conversion or validation fails,
+returns the default value.
+*/
+func Int64FromEnv(envVar string, defaultValue int64, rules ...RuleInt64) (int64, error) {
+	const op string = "xassert.Int64FromEnv"
+	value := os.Getenv(envVar)
+	result, err := Int64(envVar, value, defaultValue, rules...)
+	if err != nil {
+		return result, xerror.New(op, err)
+	}
+	return result, nil
+}
+
+/*
+Float64 tries to convert a string to a float64.
+
+If string is empty, conversion or validation fails,
+returns the default value.
+
+The key is used to identify the value.
+*/
+func Float64(key, value string, defaultValue float64, rules ...RuleFloat64) (float64, error) {
+	const op string = "xassert.Float64"
+	result := defaultValue
+	if value != "" {
+		parsedValue, err := strconv.ParseFloat(value, 64)
+		if err != nil {
+			return defaultValue, xerror.Invalid(
+				op,
+				fmt.Sprintf("'%s' is not a float, got '%s'", key, value),
+				err,
+			)
+		}
+		result = parsedValue
+	}
+	for _, rule := range rules {
+		rule.with(key, result)
+		if err := rule.validate(); err != nil {
+			return defaultValue, xerror.New(op, err)
+		}
+	}
+	return result, nil
+}
+
+/*
+Float64FromEnv returns the float64 representation of the
+value of given environment variable.
+
+If not found, empty, conversion or validation fails,
+returns the default value.
+*/
+func Float64FromEnv(envVar string, defaultValue float64, rules ...RuleFloat64) (float64, error) {
+	const op string = "xassert.Float64FromEnv"
+	value := os.Getenv(envVar)
+	result, err := Float64(envVar, value, defaultValue, rules...)
+	if err != nil {
+		return result, xerror.New(op, err)
+	}
+	return result, nil
+}
+
+/*
+Bool tries to convert a string to a boolean.
+
+If string is empty or conversion fails, returns the
+default value.
+
+The key is used to identify the value.
+*/
+func Bool(key, value string, defaultValue bool) (bool, error) {
+	const op string = "xassert.Bool"
+	result := defaultValue
+	if value != "" {
+		parsedValue, err := strconv.ParseBool(value)
+		if err != nil {
+			return defaultValue, xerror.Invalid(
+				op,
+				fmt.Sprintf("'%s' is not a boolean, got '%s'", key, value),
+				err,
+			)
+		}
+		result = parsedValue
+	}
+	return result, nil
+}
+
+/*
+BoolFromEnv returns the boolean representation of the
+value of given environment variable.
+
+If not found, empty or conversion fails, returns the
+default value.
+*/
+func BoolFromEnv(envVar string, defaultValue bool) (bool, error) {
+	const op string = "xassert.BoolFromEnv"
+	value := os.Getenv(envVar)
+	result, err := Bool(envVar, value, defaultValue)
+	if err != nil {
+		return result, xerror.New(op, err)
+	}
+	return result, nil
+}