Add config loading primitives

internal/core/config/env.go

@@ -0,0 +1,88 @@
+package config
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+
+	"gitea.maximumdirect.net/eric/notarius/internal/core/diagnostics"
+	"gitea.maximumdirect.net/eric/notarius/internal/framework/pipeline"
+)
+
+func LoadFromEnv() (Config, error) {
+	cfg := Default()
+	if err := cfg.applyEnvOverridesWithLookup(os.LookupEnv); err != nil {
+		return Config{}, err
+	}
+	return cfg, nil
+}
+
+func (c *Config) ApplyEnvOverrides() error {
+	return c.applyEnvOverridesWithLookup(os.LookupEnv)
+}
+
+func (c *Config) applyEnvOverridesWithLookup(lookup func(string) (string, bool)) error {
+	if c == nil {
+		return fmt.Errorf("config must not be nil")
+	}
+	if c.LLMProfiles == nil {
+		c.LLMProfiles = map[string]LLMProfile{}
+	}
+
+	defaultProfile := c.LLMProfiles[pipeline.DefaultLLMProfile]
+	if raw, ok := lookup("NOTARIUS_LLM_DEFAULT_API_KEY"); ok {
+		defaultProfile.APIKey = raw
+	}
+	if raw, ok := lookup("NOTARIUS_LLM_DEFAULT_BASE_URL"); ok {
+		defaultProfile.BaseURL = strings.TrimSpace(raw)
+	}
+	if raw, ok := lookup("NOTARIUS_LLM_DEFAULT_MODEL"); ok {
+		defaultProfile.Model = strings.TrimSpace(raw)
+	}
+	if raw, ok := lookup("NOTARIUS_LLM_DEFAULT_TIMEOUT_SECONDS"); ok {
+		value, err := parseIntEnv("NOTARIUS_LLM_DEFAULT_TIMEOUT_SECONDS", raw)
+		if err != nil {
+			return err
+		}
+		defaultProfile.TimeoutSeconds = value
+	}
+	if raw, ok := lookup("NOTARIUS_LLM_DEFAULT_MAX_RETRIES"); ok {
+		value, err := parseIntEnv("NOTARIUS_LLM_DEFAULT_MAX_RETRIES", raw)
+		if err != nil {
+			return err
+		}
+		defaultProfile.MaxRetries = value
+	}
+	if raw, ok := lookup("NOTARIUS_LLM_DEFAULT_MAX_CONCURRENCY"); ok {
+		value, err := parseIntEnv("NOTARIUS_LLM_DEFAULT_MAX_CONCURRENCY", raw)
+		if err != nil {
+			return err
+		}
+		defaultProfile.MaxConcurrency = value
+	}
+	c.LLMProfiles[pipeline.DefaultLLMProfile] = defaultProfile
+
+	if raw, ok := lookup("NOTARIUS_TOTAL_LLM_CONCURRENCY"); ok {
+		value, err := parseIntEnv("NOTARIUS_TOTAL_LLM_CONCURRENCY", raw)
+		if err != nil {
+			return err
+		}
+		c.Concurrency.TotalLLM = value
+	}
+	if raw, ok := lookup("NOTARIUS_WORK_DIR"); ok {
+		c.Diagnostics.WorkDir = strings.TrimSpace(raw)
+	}
+	if raw, ok := lookup("NOTARIUS_DIAGNOSTICS_RETENTION"); ok {
+		c.Diagnostics.Retention = diagnostics.RetentionMode(strings.TrimSpace(raw))
+	}
+	return nil
+}
+
+func parseIntEnv(name string, raw string) (int, error) {
+	value, err := strconv.Atoi(strings.TrimSpace(raw))
+	if err != nil {
+		return 0, fmt.Errorf("%s: must be an integer", name)
+	}
+	return value, nil
+}