Merge pull request #2 from john-peterson-g17/add-comma-list

Add functionality for parsing comma list value into a slice of strings
syntaqx · Jul 15, 2024 · 6a9ce90 · 6a9ce90
2 parents 97fb6d3 + b6e3d42
commit 6a9ce90
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Showing 5 changed files with 96 additions and 0 deletions.
diff --git a/README.md b/README.md
@@ -26,6 +26,11 @@ func main() {
 
     port := env.GetWithFallback("PORT", "8080")
     fmt.Printf("Port: %s\n", port)
+
+    // Assuming the value of HOSTS is a comma separated list of strings
+    // Example: some-host:8000,another-host:8000
+    hosts := env.GetSliceWithFallback("HOSTS", []string{"fallback-host-1:8000", "fallback-host-2:8000"})
+    fmt.Printf("Hosts: %v\n", hosts)
 }
 ```
 

diff --git a/env.go b/env.go
@@ -2,6 +2,7 @@ package env
 
 import (
 	"os"
+	"strings"
 
 	"github.com/joho/godotenv"
 )
@@ -31,6 +32,15 @@ func GetWithFallback(key string, fallback string) string {
 	return fallback
 }
 
+// GetSliceWithFallback returns the value of a comma separated environment variable as a slice
+// of strings or a fallback value if the environment variable is not set.
+func GetSliceWithFallback(key string, fallback []string) []string {
+	if value, ok := Lookup(key); ok {
+		return strings.Split(value, ",")
+	}
+	return fallback
+}
+
 // GetBool returns the value of an environment variable as a boolean.
 func GetBool(key string) bool {
 	return Get(key) == "true"

diff --git a/env_test.go b/env_test.go
@@ -3,6 +3,8 @@ package env
 import (
 	"os"
 	"testing"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestGetWithFallback(t *testing.T) {
@@ -103,3 +105,66 @@ func TestGetBoolWithFallback(t *testing.T) {
 		})
 	}
 }
+func TestGetSliceWithFallback(t *testing.T) {
+	tests := []struct {
+		setValue  bool
+		key       string
+		fallback  []string
+		envValue  string
+		wantValue []string
+	}{
+		{
+			setValue:  true,
+			key:       "EXISTING_KEY_SLICE_ONE_VALUE",
+			fallback:  []string{"fallback_value_1"},
+			envValue:  "existing_value",
+			wantValue: []string{"existing_value"},
+		},
+		{
+			setValue:  false,
+			key:       "NON_EXISTING_KEY_SLICE",
+			fallback:  []string{"fallback_value"},
+			envValue:  "",
+			wantValue: []string{"fallback_value"},
+		},
+		{
+			setValue:  true,
+			key:       "EMPTY_VALUE_KEY_SLICE",
+			fallback:  []string{"fallback_value"},
+			envValue:  "",
+			wantValue: []string{""},
+		},
+		{
+			setValue:  true,
+			key:       "EXISTING_KEY_SLICE_MULTI_VALUE",
+			fallback:  []string{"fallback_value_1", "fallback_value_2"},
+			envValue:  "existing_value_1,existing_value_2",
+			wantValue: []string{"existing_value_1", "existing_value_2"},
+		},
+		{
+			setValue:  false,
+			key:       "NON_EXISTING_KEY_SLICE_MULTI_VALUE",
+			fallback:  []string{"fallback_value_1", "fallback_value_2"},
+			envValue:  "",
+			wantValue: []string{"fallback_value_1", "fallback_value_2"},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.key, func(t *testing.T) {
+			// Set the environment variable
+			if tt.setValue {
+				os.Setenv(tt.key, tt.envValue)
+			}
+
+			// Call the function under test
+			got := GetSliceWithFallback(tt.key, tt.fallback)
+
+			// Check if the returned value matches the expected value
+			assert.ElementsMatch(t, tt.wantValue, got, "GetSliceWithFallback(%q, %q) should return expected slice elements, order ignored", tt.key, tt.fallback)
+
+			// Unset the environment variable
+			os.Unsetenv(tt.key)
+		})
+	}
+}
diff --git a/go.mod b/go.mod
@@ -3,3 +3,10 @@ module github.com/syntaqx/env
 go 1.22.3
 
 require github.com/joho/godotenv v1.5.1
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/stretchr/testify v1.9.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)
diff --git a/go.sum b/go.sum
@@ -1,2 +1,11 @@
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/joho/godotenv v1.5.1 h1:7eLL/+HRGLY0ldzfGMeQkb7vMd0as4CfYvUVzLqw0N0=
 github.com/joho/godotenv v1.5.1/go.mod h1:f4LDr5Voq0i2e/R5DDNOoa2zzDfwtkZa6DnEwAbqwq4=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
+github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=