Release 0.2

doc.go

@@ -12,13 +12,12 @@
 //
 // This allows you to Unmarshal JSON or YAML into:
 //
-//      type myConfig struct {
-//              Server    config.URL
-//              TLS       config.TLS
-//      }
+//	type myConfig struct {
+//	        Server    config.URL
+//	        TLS       config.TLS
+//	}
 //
 // and have a net/url url.URL value available as cfg.Server.URL, and
 // a TLS configuration as cfg.TLS.Config, with the config package taking
 // care of parsing and validation.
-//
 package config

env/env.go

@@ -14,10 +14,10 @@
 // Configuration can come from hardcoded defaults, environment, configuration
 // files, and command line flags. To implement the usual precedence of:
 //
-//      1) built-in defaults (lowest)
-//      2) environment parameters
-//      3) configuration file parameters
-//      4) command line parameters (highest)
+//  1. built-in defaults (lowest)
+//  2. environment parameters
+//  3. configuration file parameters
+//  4. command line parameters (highest)
 //
 // define defaults and command line bindings (with the flag package) first,
 // followed by environment bindings with this package. Then load values from
@@ -30,6 +30,7 @@
 package env
 
 import (
+	"fmt"
 	"os"
 	"strconv"
 	"time"
@@ -155,3 +156,67 @@ func (d *durationValue) Set(s string) error {
 func DurationVar(d *time.Duration, key string) error {
 	return Var((*durationValue)(d), key)
 }
+
+// ErrorHandling has advantage over bool as it can be extended
+// to handle additional cases whereas bool cannot
+type ErrorHandling int
+
+const (
+	ContinueOnError ErrorHandling = 0
+	ExitOnError                   = 1
+)
+
+type envConfig struct {
+	errorHandling ErrorHandling
+}
+
+// NewConfig creates an envConfig object which allows handling of env variable parsing error
+func NewConfig(errorHandling ErrorHandling) envConfig {
+	return envConfig{errorHandling: errorHandling}
+}
+
+// handleError handles envConfig on error behavior
+func (e *envConfig) handleError(key string, err error) error {
+	if err != nil && e.errorHandling == ExitOnError {
+		fmt.Fprintf(os.Stderr, "%s encountered parsing error: %v\n", key, err)
+		os.Exit(1)
+	}
+
+	return err
+}
+
+func (e *envConfig) StringVar(v *string, key string) error {
+	return e.handleError(key, StringVar(v, key))
+}
+
+func (e *envConfig) BoolVar(v *bool, key string) error {
+	return e.handleError(key, BoolVar(v, key))
+}
+
+func (e *envConfig) IntVar(v *int, key string) error {
+	return e.handleError(key, IntVar(v, key))
+}
+
+func (e *envConfig) Int64Var(v *int64, key string) error {
+	return e.handleError(key, Int64Var(v, key))
+}
+
+func (e *envConfig) UintVar(v *uint, key string) error {
+	return e.handleError(key, UintVar(v, key))
+}
+
+func (e *envConfig) Uint64Var(v *uint64, key string) error {
+	return e.handleError(key, Uint64Var(v, key))
+}
+
+func (e *envConfig) Float64Var(v *float64, key string) error {
+	return e.handleError(key, Float64Var(v, key))
+}
+
+func (e *envConfig) DurationVar(v *time.Duration, key string) error {
+	return e.handleError(key, DurationVar(v, key))
+}
+
+func (e *envConfig) Var(v Value, key string) error {
+	return e.handleError(key, Var(v, key))
+}

env/env_test.go

@@ -1,5 +1,5 @@
 /*
- * Copyright 2018 Farsight Security, Inc.
+ * Copyright 2023 Farsight Security, Inc.
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -9,6 +9,7 @@
 package env
 
 import (
+	"github.com/farsightsec/go-config"
 	"os"
 	"testing"
 	"time"
@@ -59,3 +60,32 @@ func TestEnvMissing(t *testing.T) {
 	checkOK(t, IntVar(&i, "TEST_MISSING"), i == 10)
 	checkOK(t, BoolVar(&b, "TEST_MISSING"), b)
 }
+
+func TestEnvConfig(t *testing.T) {
+	var i int = 0
+	var i64 int64 = 0
+	var u uint = 0
+	var u64 uint64 = 0
+	var f64 float64 = 0
+	var s string = ""
+	var b bool = false
+	var d time.Duration = time.Second
+	var ss = config.String{}
+
+	ec := NewConfig(ContinueOnError)
+
+	checkOK(t, ec.IntVar(&i, "TEST_NUM"), i == 1048576)
+	checkOK(t, ec.Int64Var(&i64, "TEST_NUM"), i64 == 1048576)
+	checkOK(t, ec.UintVar(&u, "TEST_NUM"), u == 1048576)
+	checkOK(t, ec.Uint64Var(&u64, "TEST_NUM"), u64 == 1048576)
+	checkOK(t, ec.Float64Var(&f64, "TEST_NUM"), f64 == 1048576)
+	checkOK(t, ec.StringVar(&s, "TEST_NUM"), s == "1048576")
+	checkOK(t, ec.Var(&ss, "TEST_NUM"), ss.String() == "1048576")
+	checkOK(t, ec.DurationVar(&d, "TEST_DURATION"), d == 100*time.Millisecond)
+	checkOK(t, ec.BoolVar(&b, "TEST_BOOL_TRUE"), b)
+	checkOK(t, ec.BoolVar(&b, "TEST_BOOL_FALSE"), !b)
+
+	if ec.BoolVar(&b, "TEST_BOOL_INVALID") == nil {
+		t.Error("Expected parse error")
+	}
+}

go.mod

@@ -0,0 +1,5 @@
+module github.com/farsightsec/go-config
+
+go 1.18
+
+require gopkg.in/yaml.v2 v2.4.0

go.sum

@@ -0,0 +1,4 @@
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
+gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=

tls.go

@@ -21,6 +21,7 @@ import (
 // conversion to and from string format.
 //
 // Supported string values are:
+//
 //	"none":           tls.NoClientCert  (default)
 //	"request":        tls.RequestClientCert
 //	"require":        tls.RequireAnyClientCert
@@ -49,13 +50,13 @@ func (auth *TLSClientAuth) String() string {
 type invalidClientAuthType string
 
 func (i invalidClientAuthType) Error() string {
-	return fmt.Sprintf(`Invalid ClientAuthType "%s".`, i)
+	return fmt.Sprintf(`Invalid ClientAuthType "%s".`, string(i))
 }
 
 type invalidClientAuthTypeValue tls.ClientAuthType
 
 func (i invalidClientAuthTypeValue) Error() string {
-	return fmt.Sprintf("Invalid ClientAuthType value %v", i)
+	return fmt.Sprintf("Invalid ClientAuthType value %v", int(i))
 }
 
 // Set satisfies the flag.Value interface.