github.com/gofiber/fiber/v2@v2.47.0/docs/api/middleware/envvar.md (about) 1 --- 2 id: envvar 3 title: EnvVar 4 --- 5 6 EnvVar middleware for [Fiber](https://github.com/gofiber/fiber) that can be used to expose environment variables with various options. 7 8 ## Signatures 9 10 ```go 11 func New(config ...Config) fiber.Handler 12 ``` 13 14 ## Examples 15 16 Import the middleware package that is part of the Fiber web framework 17 18 ```go 19 import ( 20 "github.com/gofiber/fiber/v2" 21 "github.com/gofiber/fiber/v2/middleware/envvar" 22 ) 23 ``` 24 25 After you initiate your Fiber app, you can use the following possibilities: 26 27 ```go 28 // Initialize default config 29 app.Use("/expose/envvars", envvar.New()) 30 31 // Or extend your config for customization 32 app.Use("/expose/envvars", envvar.New( 33 envvar.Config{ 34 ExportVars: map[string]string{"testKey": "", "testDefaultKey": "testDefaultVal"}, 35 ExcludeVars: map[string]string{"excludeKey": ""}, 36 }), 37 ) 38 ``` 39 40 :::note 41 You will need to provide a path to use the envvar middleware. 42 ::: 43 44 ## Response 45 46 Http response contract: 47 ``` 48 { 49 "vars": { 50 "someEnvVariable": "someValue", 51 "anotherEnvVariable": "anotherValue", 52 } 53 } 54 55 ``` 56 57 ## Config 58 59 ```go 60 // Config defines the config for middleware. 61 type Config struct { 62 // ExportVars specifies the environment variables that should export 63 ExportVars map[string]string 64 // ExcludeVars specifies the environment variables that should not export 65 ExcludeVars map[string]string 66 } 67 68 ``` 69 70 ## Default Config 71 72 ```go 73 Config{} 74 ```