config: refactor into multiple files (#782)

lib/config/aws.go

@@ -0,0 +1,33 @@
+package config
+
+import (
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/credentials"
+	"github.com/aws/aws-sdk-go/aws/session"
+)
+
+// AWS configures credentials for access to Amazon Web Services.
+// It is intended to be used in composition rather than a key.
+type AWS struct {
+	AccessKeyID     string `json:"access_key_id"`
+	AccessKeySecret string `json:"access_key_secret"`
+
+	Region string `json:"region,omitempty"`
+}
+
+// Credentials returns a configured set of AWS credentials.
+func (a AWS) Credentials() *credentials.Credentials {
+	if a.AccessKeyID != "" && a.AccessKeySecret != "" {
+		return credentials.NewStaticCredentials(a.AccessKeyID, a.AccessKeySecret, "")
+	}
+
+	return nil
+}
+
+// Session returns an AWS Session configured with region and credentials.
+func (a AWS) Session() (*session.Session, error) {
+	return session.NewSession(&aws.Config{
+		Region:      aws.String(a.Region),
+		Credentials: a.Credentials(),
+	})
+}

lib/config/context.go

@@ -0,0 +1,24 @@
+package config
+
+import (
+	"context"
+	"os"
+	"os/signal"
+	"syscall"
+)
+
+func ContextWithCancelOnSignal(ctx context.Context) context.Context {
+	ctx, cancel := context.WithCancel(ctx)
+	stop := make(chan os.Signal, 1)
+	signal.Notify(stop, os.Interrupt, syscall.SIGTERM, syscall.SIGINT)
+
+	go func() {
+		defer cancel()
+		select {
+		case <-stop:
+		case <-ctx.Done():
+		}
+	}()
+
+	return ctx
+}

lib/config/jwt.go

@@ -0,0 +1,9 @@
+package config
+
+// JWT configures public (and optionally private) keys and issuer for
+// JSON Web Tokens. It is intended to be used in composition rather than a key.
+type JWT struct {
+	Issuer  string `json:"issuer"`
+	Public  string `json:"public"`
+	Private string `json:"private,omitempty"`
+}