1 files changed, 126 insertions, 0 deletions
diff --git a/internal/configuration/sources.go b/internal/configuration/sources.go
new file mode 100644
index 000000000..90510ee2d
--- /dev/null
+++ b/internal/configuration/sources.go
@@ -0,0 +1,126 @@
+package configuration
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/knadh/koanf"
+	"github.com/knadh/koanf/parsers/yaml"
+	"github.com/knadh/koanf/providers/env"
+	"github.com/knadh/koanf/providers/file"
+
+	"github.com/authelia/authelia/internal/configuration/schema"
+	"github.com/authelia/authelia/internal/configuration/validator"
+)
+
+// NewYAMLFileSource returns a Source configured to load from a specified YAML path. If there is an issue accessing this
+// path it also returns an error.
+func NewYAMLFileSource(path string) (source *YAMLFileSource) {
+	return &YAMLFileSource{
+		koanf: koanf.New(constDelimiter),
+		path:  path,
+	}
+}
+
+// NewYAMLFileSources returns a slice of Source configured to load from specified YAML files.
+func NewYAMLFileSources(paths []string) (sources []*YAMLFileSource) {
+	for _, path := range paths {
+		source := NewYAMLFileSource(path)
+
+		sources = append(sources, source)
+	}
+
+	return sources
+}
+
+// Name of the Source.
+func (s YAMLFileSource) Name() (name string) {
+	return fmt.Sprintf("yaml file(%s)", s.path)
+}
+
+// Merge the YAMLFileSource koanf.Koanf into the provided one.
+func (s *YAMLFileSource) Merge(ko *koanf.Koanf, _ *schema.StructValidator) (err error) {
+	return ko.Merge(s.koanf)
+}
+
+// Load the Source into the YAMLFileSource koanf.Koanf.
+func (s *YAMLFileSource) Load(_ *schema.StructValidator) (err error) {
+	if s.path == "" {
+		return errors.New("invalid yaml path source configuration")
+	}
+
+	return s.koanf.Load(file.Provider(s.path), yaml.Parser())
+}
+
+// NewEnvironmentSource returns a Source configured to load from environment variables.
+func NewEnvironmentSource(prefix, delimiter string) (source *EnvironmentSource) {
+	return &EnvironmentSource{
+		koanf:     koanf.New(constDelimiter),
+		prefix:    prefix,
+		delimiter: delimiter,
+	}
+}
+
+// Name of the Source.
+func (s EnvironmentSource) Name() (name string) {
+	return "environment"
+}
+
+// Merge the EnvironmentSource koanf.Koanf into the provided one.
+func (s *EnvironmentSource) Merge(ko *koanf.Koanf, _ *schema.StructValidator) (err error) {
+	return ko.Merge(s.koanf)
+}
+
+// Load the Source into the EnvironmentSource koanf.Koanf.
+func (s *EnvironmentSource) Load(_ *schema.StructValidator) (err error) {
+	keyMap, ignoredKeys := getEnvConfigMap(validator.ValidKeys, s.prefix, s.delimiter)
+
+	return s.koanf.Load(env.ProviderWithValue(s.prefix, constDelimiter, koanfEnvironmentCallback(keyMap, ignoredKeys, s.prefix, s.delimiter)), nil)
+}
+
+// NewSecretsSource returns a Source configured to load from secrets.
+func NewSecretsSource(prefix, delimiter string) (source *SecretsSource) {
+	return &SecretsSource{
+		koanf:     koanf.New(constDelimiter),
+		prefix:    prefix,
+		delimiter: delimiter,
+	}
+}
+
+// Name of the Source.
+func (s SecretsSource) Name() (name string) {
+	return "secrets"
+}
+
+// Merge the SecretsSource koanf.Koanf into the provided one.
+func (s *SecretsSource) Merge(ko *koanf.Koanf, val *schema.StructValidator) (err error) {
+	for _, key := range s.koanf.Keys() {
+		value, ok := ko.Get(key).(string)
+
+		if ok && value != "" {
+			val.Push(fmt.Errorf(errFmtSecretAlreadyDefined, key))
+		}
+	}
+
+	return ko.Merge(s.koanf)
+}
+
+// Load the Source into the SecretsSource koanf.Koanf.
+func (s *SecretsSource) Load(val *schema.StructValidator) (err error) {
+	keyMap := getSecretConfigMap(validator.ValidKeys, s.prefix, s.delimiter)
+
+	return s.koanf.Load(env.ProviderWithValue(s.prefix, constDelimiter, koanfEnvironmentSecretsCallback(keyMap, val)), nil)
+}
+
+// NewDefaultSources returns a slice of Source configured to load from specified YAML files.
+func NewDefaultSources(filePaths []string, prefix, delimiter string) (sources []Source) {
+	fileSources := NewYAMLFileSources(filePaths)
+	for _, source := range fileSources {
+		sources = append(sources, source)
+	}
+
+	sources = append(sources, NewEnvironmentSource(prefix, delimiter))
+	sources = append(sources, NewSecretsSource(prefix, delimiter))
+
+	return sources
+}