From 9e7732899d3462495f2d6e8b67d534eedc0091cb Mon Sep 17 00:00:00 2001
From: Christoph Hartmann <chris@lollyrock.com>
Date: Fri, 23 Sep 2022 15:58:36 +0200
Subject: [PATCH] =?UTF-8?q?=E2=AD=90=EF=B8=8F=20request=20scope=20plugin?=
 =?UTF-8?q?=20(#21)?=
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Signed-off-by: Christoph Hartmann <chris@lollyrock.com>
---
 go.mod                              |  1 +
 go.sum                              |  2 ++
 plugins/scope/request_scope.go      | 49 +++++++++++++++++++++++++++++
 plugins/scope/request_scope_test.go | 40 +++++++++++++++++++++++
 4 files changed, 92 insertions(+)
 create mode 100644 plugins/scope/request_scope.go
 create mode 100644 plugins/scope/request_scope_test.go

diff --git a/go.mod b/go.mod
index 868feb5..b0f0970 100644
--- a/go.mod
+++ b/go.mod
@@ -6,6 +6,7 @@ require (
 	github.com/cockroachdb/errors v1.9.0
 	github.com/go-openapi/spec v0.20.6
 	github.com/google/go-cmp v0.5.8
+	github.com/google/uuid v1.3.0
 	github.com/lyft/protoc-gen-star v0.6.1
 	github.com/rs/zerolog v1.27.0
 	github.com/stretchr/testify v1.8.0
diff --git a/go.sum b/go.sum
index efc4f40..bf75a2d 100644
--- a/go.sum
+++ b/go.sum
@@ -198,6 +198,8 @@ github.com/google/pprof v0.0.0-20201203190320-1bf35d6f28c2/go.mod h1:kpwsk12EmLe
 github.com/google/pprof v0.0.0-20201218002935-b9804c9f04c2/go.mod h1:kpwsk12EmLew5upagYY7GY0pfYCcupk39gWOCRROcvE=
 github.com/google/renameio v0.1.0/go.mod h1:KWCgfxg9yswjAJkECMjeO8J8rahYeXnNhOm40UhjYkI=
 github.com/google/uuid v1.1.2/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
+github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/googleapis/gax-go/v2 v2.0.4/go.mod h1:0Wqv26UfaUD9n4G6kQubkQ+KchISgw+vpHVxEJEs9eg=
 github.com/googleapis/gax-go/v2 v2.0.5/go.mod h1:DWXyrwAJ9X0FpwwEdw+IPEYBICEFu5mhpdKc/us6bOk=
 github.com/googleapis/google-cloud-go-testing v0.0.0-20200911160855-bcd43fbb19e8/go.mod h1:dvDLG8qkwmyD9a/MJJN3XJcT3xFxOKAvTZGvuZmac9g=
diff --git a/plugins/scope/request_scope.go b/plugins/scope/request_scope.go
new file mode 100644
index 0000000..464a410
--- /dev/null
+++ b/plugins/scope/request_scope.go
@@ -0,0 +1,49 @@
+package scope
+
+import (
+	"net/http"
+
+	"github.com/google/uuid"
+	"go.mondoo.com/ranger-rpc"
+)
+
+const XRequestID = "X-Request-ID"
+
+type RequestIdOption func(s *requestIdPlugin)
+
+func WithUuid(requestId string) RequestIdOption {
+	return func(s *requestIdPlugin) {
+		s.requestID = requestId
+	}
+}
+
+// NewRequestIDPlugin creates a RangerPlugin that adds the
+// X-Request-ID header to outgoing requests. All RPCs
+// that share the same RangerPlugin will get the same ID
+func NewRequestIDRangerPlugin(opts ...RequestIdOption) ranger.ClientPlugin {
+	p := &requestIdPlugin{}
+
+	for i := range opts {
+		opts[i](p)
+	}
+
+	if p.requestID == "" {
+		p.requestID = uuid.New().String()
+	}
+
+	return p
+}
+
+type requestIdPlugin struct {
+	requestID string
+}
+
+func (p *requestIdPlugin) GetName() string {
+	return "Request Scope Plugin"
+}
+
+func (p *requestIdPlugin) GetHeader(data []byte) http.Header {
+	header := make(http.Header)
+	header.Set(XRequestID, p.requestID)
+	return header
+}
diff --git a/plugins/scope/request_scope_test.go b/plugins/scope/request_scope_test.go
new file mode 100644
index 0000000..80b019f
--- /dev/null
+++ b/plugins/scope/request_scope_test.go
@@ -0,0 +1,40 @@
+package scope
+
+import (
+	"testing"
+
+	"github.com/google/uuid"
+	"github.com/stretchr/testify/require"
+)
+
+func TestRequestScopePlugin(t *testing.T) {
+	t.Run("header is valid uuid", func(t *testing.T) {
+		p := NewRequestIDRangerPlugin()
+		header := p.GetHeader(nil)
+		headerValue := header.Get(XRequestID)
+		require.NotEmpty(t, headerValue)
+		_, err := uuid.Parse(headerValue)
+		require.NoError(t, err)
+	})
+
+	t.Run("multiple calls produce the same value", func(t *testing.T) {
+		p := NewRequestIDRangerPlugin()
+		headerValue1 := p.GetHeader(nil).Get(XRequestID)
+		headerValue2 := p.GetHeader(nil).Get(XRequestID)
+		require.Equal(t, headerValue1, headerValue2)
+	})
+
+	t.Run("uniqueness", func(t *testing.T) {
+		p1 := NewRequestIDRangerPlugin()
+		p2 := NewRequestIDRangerPlugin()
+		headerValue1 := p1.GetHeader(nil).Get(XRequestID)
+		headerValue2 := p2.GetHeader(nil).Get(XRequestID)
+		require.NotEqual(t, headerValue1, headerValue2)
+	})
+
+	t.Run("custom uuid", func(t *testing.T) {
+		p1 := NewRequestIDRangerPlugin(WithUuid("custom-uuid"))
+		headerValue1 := p1.GetHeader(nil).Get(XRequestID)
+		require.Equal(t, "custom-uuid", headerValue1)
+	})
+}