[#17] wrap env loading inside library implementation with unit tests

parse.go

@@ -0,0 +1,36 @@
+package goconf
+
+import "github.com/caarlos0/env/v11"
+
+// ParseEnv parse the env values to given struct fields
+// env variables are defined using struct tags. It utilizes the "github.com/caarlos0/env/v11"
+// package for parse.
+//
+// Parameters:
+//   - config (interface{}): The struct to be populated by env variables. The struct should have
+//     env variables defined using tags such as `env:"USERNAME"`.
+//
+// Returns:
+//   - error: Returns nil if the struct created using env variables. if fails, it returns an error
+//     which provides details information about the error
+//
+// Usage Example:
+//
+//		type Config struct {
+//		    Name string `env:"MY_NAME"`
+//		    Age  int    `env:"MY_AGE"`
+//	     Team string `env:"MY_TEAM" envDefault:"Backend"`
+//		}
+//
+//		var conf Config
+//		if err := Register(&conf); err != nil {
+//		    // Handle env pass error, e.g., log or return
+//		}
+//
+// Note:
+//   - The function will panic if the `config` parameter is not a pointer to struct
+//
+// More env package information https://github.com/caarlos0/env/v11
+func ParseEnv(config interface{}) error {
+	return env.Parse(config)
+}

parse_test.go

@@ -0,0 +1,81 @@
+package goconf
+
+import (
+	"github.com/stretchr/testify/assert"
+	"os"
+	"testing"
+)
+
+type Conf struct {
+	Name string `env:"MY_NAME"`
+	Age  int    `env:"MY_AGE"`
+	Team string `env:"MY_TEAM"`
+}
+
+func TestParseEnv_Success(t *testing.T) {
+	updateEnv()
+	tests := []struct {
+		name           string
+		input          Conf
+		expectedOutput Conf
+		errorExpected  bool
+	}{
+		{
+			name:  "Successfully parsed the configs",
+			input: Conf{},
+			expectedOutput: Conf{
+				Name: "coderx",
+				Age:  99,
+				Team: "backend",
+			},
+			errorExpected: false,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			err := ParseEnv(&test.input)
+			if !test.errorExpected {
+				assert.NoError(t, err)
+				assert.Equal(t, test.expectedOutput, test.input)
+			} else {
+				assert.Error(t, err)
+			}
+		})
+	}
+}
+
+func TestParseEnv_Failure(t *testing.T) {
+	updateEnv()
+	tests := []struct {
+		name           string
+		input          *Conf
+		expectedOutput *Conf
+		errorExpected  bool
+	}{
+		{
+			name:           "config parse failure scenario",
+			input:          &Conf{},
+			expectedOutput: &Conf{},
+			errorExpected:  true,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			err := ParseEnv(&test.input)
+			if !test.errorExpected {
+				assert.NoError(t, err)
+				assert.Equal(t, test.expectedOutput, test.input)
+			} else {
+				assert.Error(t, err)
+			}
+		})
+	}
+}
+
+func updateEnv() {
+	_ = os.Setenv("MY_NAME", "coderx")
+	_ = os.Setenv("MY_AGE", "99")
+	_ = os.Setenv("MY_TEAM", "backend")
+}