2 files changed, 123 insertions, 0 deletions
diff --git a/internal/config/config.go b/internal/config/config.go
new file mode 100644
index 0000000..2df7d98
--- /dev/null
+++ b/internal/config/config.go
@@ -0,0 +1,52 @@
+package config
+
+import (
+	"fmt"
+	"gopkg.in/yaml.v3"
+	"io/ioutil"
+)
+
+type Map map[string]interface{}
+type Feeds map[string]*Feed
+
+type config struct {
+	GlobalConfig Map `yaml:",inline"`
+	Feeds        []configGroupFeed
+}
+
+type Config struct {
+	GlobalConfig Map `yaml:",inline"`
+	Feeds        Feeds
+}
+
+type Feed struct {
+	Name    string
+	Target  string
+	Url     string
+	MinFreq int
+	Config  Map
+}
+
+func Load(path string) (*Config, error) {
+	buf, err := ioutil.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("while reading '%s': %w", path, err)
+	}
+
+	var parsedCfg config
+	if err := yaml.Unmarshal(buf, &parsedCfg); err != nil {
+		return nil, fmt.Errorf("while unmarshalling: %w", err)
+	}
+	fmt.Printf("--- parsedCfg:\n%+v\n\n", parsedCfg)
+
+	var finishedCfg = Config{
+		GlobalConfig: parsedCfg.GlobalConfig,
+		Feeds:        make(Feeds),
+	}
+
+	if err := buildFeeds(parsedCfg.Feeds, "", finishedCfg.Feeds); err != nil {
+		return nil, fmt.Errorf("while parsing: %w", err)
+	}
+
+	return &finishedCfg, nil
+}
diff --git a/internal/config/yaml.go b/internal/config/yaml.go
new file mode 100644
index 0000000..335dede
--- /dev/null
+++ b/internal/config/yaml.go
@@ -0,0 +1,71 @@
+package config
+
+import "fmt"
+
+type Group struct {
+	Group string
+	Feeds []configGroupFeed
+}
+
+type configGroupFeed struct {
+	Target *string
+	Feed   `yaml:",inline"`
+	Group  `yaml:",inline"`
+}
+
+func (grpFeed *configGroupFeed) isGroup() bool {
+	return grpFeed.Group.Group != ""
+}
+
+func (grpFeed *configGroupFeed) isFeed() bool {
+	return grpFeed.Name != ""
+}
+
+func (grpFeed *configGroupFeed) target() string {
+	if grpFeed.Target != nil {
+		return *grpFeed.Target
+	}
+	if grpFeed.Name != "" {
+		return grpFeed.Name
+	}
+
+	return grpFeed.Group.Group
+}
+
+func appTarget(target, app string) string {
+	if target == "" {
+		return app
+	}
+
+	if app == "" {
+		return target
+	}
+
+	return target + "/" + app
+}
+
+// Parse the group structure and populate the `Target` fields in the feeds
+func buildFeeds(cfg []configGroupFeed, target string, feeds Feeds) error {
+	for _, f := range cfg {
+		target := appTarget(target, f.target())
+		switch {
+		case f.isFeed() && f.isGroup():
+			return fmt.Errorf("Entry with Target %s is both a Feed and a group", target)
+
+		case f.isFeed():
+			name := f.Feed.Name
+			if _, ok := feeds[name]; !ok {
+				return fmt.Errorf("Duplicate Feed Name '%s'", name)
+			}
+			f.Feed.Target = target
+			feeds[name] = &f.Feed
+
+		case f.isGroup():
+			if err := buildFeeds(f.Group.Feeds, target, feeds); err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}