import "github.com/lensesio/lenses-go"

// Prepare authentication using raw Username and Password.
//
// Use it when Lenses setup with "BASIC" or "LDAP" authentication.
auth := lenses.BasicAuthentication{Username: "user", Password: "pass"}

auth := lenses.KerberosAuthentication{
    ConfFile: "/etc/krb5.conf",
    Method:   lenses.KerberosWithPassword{
        Realm: "my.realm or default if empty",
        Username: "user",
        Password: "pass",
    },
}

auth := lenses.KerberosAuthentication{
    ConfFile: "/etc/krb5.conf",
    Method:   lenses.KerberosWithKeytab{KeytabFile: "/home/me/krb5_my_keytab.txt"},
}

auth := lenses.KerberosAuthentication{
    ConfFile: "/etc/krb5.conf",
    Method:   lenses.KerberosFromCCache{CCacheFile: "/tmp/krb5_my_cache_file.conf"},
}

// Prepare the client's configuration based on the host and the authentication above.
currentConfig := lenses.ClientConfig{Host: "domain.com", Authentication: auth, Timeout: "15s", Debug: true}

// Creating the client using the configuration.
client, err := lenses.OpenConnection(currentConfig)
if err != nil {
    // handle error.
}

// ReadConfig reads and decodes Config from an io.Reader based on a custom unmarshaler.
// This can be useful to read configuration via network or files (see `ReadConfigFromFile`).
// Sets the `outPtr`. Retruns a non-nil error on any unmarshaler's errors.
ReadConfig(r io.Reader, unmarshaler UnmarshalFunc, outPtr *Config) error

// ReadConfigFromFile reads and decodes Config from a file based on a custom unmarshaler,
// `ReadConfigFromJSON` and `ReadConfigFromYAML` are the internal users,
// but the end-developer can use any custom type of decoder to read a configuration file
// with ease using this function, but keep note that the default behavior of the fields
// depend on the existing unmarshalers, use these tag names to map your decoder's properties.
//
// Accepts the absolute or the relative path of the configuration file.
// Sets the `outPtr`. Retruns a non-nil error if parsing or decoding the file failed or file doesn't exist.
ReadConfigFromFile(filename string, unmarshaler UnmarshalFunc, outPtr *Config) error

// TryReadConfigFromFile will try to read a specific file and unmarshal to `Config`.
// It will try to read it with one of these built'n formats:
// 1. JSON
// 2. YAML
TryReadConfigFromFile(filename string, outPtr *Config) error

// TryReadConfigFromHome will try to read the `Config`
// from the current user's home directory/.lenses, the lookup is based on
// the common configuration filename pattern:
// lenses-cli.json, lenses-cli.yml or lenses.json and lenses.yml.
TryReadConfigFromHome(outPtr *Config) bool

// TryReadConfigFromExecutable will try to read the `Config`
// from the (client's caller's) executable path that started the current process.
// The lookup is based on the common configuration filename pattern:
// lenses-cli.json, lenses-cli.yml or lenses.json and lenses.yml.
TryReadConfigFromExecutable(outPtr *Config) bool

// TryReadConfigFromCurrentWorkingDir will try to read the `Config`
// from the current working directory, note that it may differs from the executable path.
// The lookup is based on the common configuration filename pattern:
// lenses-cli.json, lenses-cli.yml or lenses.json and lenses.yml.
TryReadConfigFromCurrentWorkingDir(outPtr *Config) bool

// ReadConfigFromJSON reads and decodes Config from a json file, i.e `configuration.json`.
//
// Accepts the absolute or the relative path of the configuration file.
// Error may occur when the file doesn't exists or is not formatted correctly.
ReadConfigFromJSON(filename string, outPtr *Config) error

// ReadConfigFromYAML reads and decodes Config from a yaml file, i.e `configuration.yml`.
//
// Accepts the absolute or the relative path of the configuration file.
// Error may occur when the file doesn't exists or is not formatted correctly.
ReadConfigFromYAML(filename string, outPtr *Config) error

var config lenses.Config
err := lenses.ReadConfigFromYAML("./lenses.yml", &config)
if err != nil {
    // handle error.
}

client, err := lenses.OpenConnection(*config.GetCurrent())

topics, err := client.GetTopics()
if err != nil {
    // handle error.
}

// Print the length of the topics we've just received from our Lenses Box.
print(len(topics))

topics[0].ConsumersGroup[0].Coordinator.Host