syz-cluster: separate global env from global config

Environment variables are convenient for storing values like DB or GCS
bucket names, but structured formats are more convenient for the actual
service configuration.

Separate global-config from global-config-env and add the functionality
that queries and parses the config options.

1 files changed, 61 insertions, 0 deletions

diff --git a/syz-cluster/pkg/app/config.go b/syz-cluster/pkg/app/config.go
new file mode 100644
index 000000000..b56d32dbd
--- /dev/null
+++ b/syz-cluster/pkg/app/config.go
@@ -0,0 +1,61 @@
+// Copyright 2025 syzkaller project authors. All rights reserved.
+// Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+package app
+
+import (
+	"fmt"
+	"os"
+	"sync"
+
+	"gopkg.in/yaml.v3"
+)
+
+type AppConfig struct {
+	// How many workflows are scheduled in parallel.
+	ParallelWorkflows int `yaml:"parallelWorkflows"`
+	// What Lore archives are to be polled for new patch series.
+	LoreArchives []string `yaml:"loreArchives"`
+}
+
+// The project configuration is expected to be mounted at /config/config.yaml.
+
+func Config() (*AppConfig, error) {
+	configLoadedOnce.Do(loadConfig)
+	return config, configErr
+}
+
+const configPath = `/config/config.yaml`
+
+var configLoadedOnce sync.Once
+var configErr error
+var config *AppConfig
+
+func loadConfig() {
+	data, err := os.ReadFile(configPath)
+	if err != nil {
+		configErr = fmt.Errorf("failed to read %q: %w", configPath, err)
+		return
+	}
+	obj := AppConfig{
+		ParallelWorkflows: 1,
+	}
+	err = yaml.Unmarshal(data, &obj)
+	if err != nil {
+		configErr = fmt.Errorf("failed to parse: %w", err)
+		return
+	}
+	err = obj.Validate()
+	if err != nil {
+		configErr = err
+		return
+	}
+	config = &obj
+}
+
+func (c AppConfig) Validate() error {
+	if c.ParallelWorkflows < 0 {
+		return fmt.Errorf("parallelWorkflows must be non-negative")
+	}
+	return nil
+}