feat(query): add source to query request via user agent header

CHANGELOG.md

@@ -28,6 +28,7 @@
 1. [16014](https://github.com/influxdata/influxdb/pull/16014): While creating check, also display notification rules that would match check based on tag rules
 1. [16389](https://github.com/influxdata/influxdb/pull/16389): Increase default bucket retention period to 30 days
 1. [16418](https://github.com/influxdata/influxdb/pull/16418): Add Developer Documentation
+1. [16260](https://github.com/influxdata/influxdb/pull/16260): Capture User-Agent header as query source for logging purposes
 
 ### Bug Fixes
 

http/query_handler.go

@@ -155,6 +155,7 @@ func (h *FluxHandler) handleQuery(w http.ResponseWriter, r *http.Request) {
 		h.HandleHTTPError(ctx, err, w)
 		return
 	}
+	req.Request.Source = r.Header.Get("User-Agent")
 	orgID = req.Request.OrganizationID
 	requestBytes = n
 
@@ -349,6 +350,7 @@ var _ query.ProxyQueryService = (*FluxService)(nil)
 type FluxService struct {
 	Addr               string
 	Token              string
+	Name               string
 	InsecureSkipVerify bool
 }
 
@@ -383,6 +385,11 @@ func (s *FluxService) Query(ctx context.Context, w io.Writer, r *query.ProxyRequ
 
 	hreq.Header.Set("Content-Type", "application/json")
 	hreq.Header.Set("Accept", "text/csv")
+	if r.Request.Source != "" {
+		hreq.Header.Add("User-Agent", r.Request.Source)
+	} else if s.Name != "" {
+		hreq.Header.Add("User-Agent", s.Name)
+	}
 	hreq = hreq.WithContext(ctx)
 
 	hc := NewClient(u.Scheme, s.InsecureSkipVerify)
@@ -412,6 +419,7 @@ var _ query.QueryService = (*FluxQueryService)(nil)
 type FluxQueryService struct {
 	Addr               string
 	Token              string
+	Name               string
 	InsecureSkipVerify bool
 }
 
@@ -450,6 +458,11 @@ func (s *FluxQueryService) Query(ctx context.Context, r *query.Request) (flux.Re
 
 	hreq.Header.Set("Content-Type", "application/json")
 	hreq.Header.Set("Accept", "text/csv")
+	if r.Source != "" {
+		hreq.Header.Add("User-Agent", r.Source)
+	} else if s.Name != "" {
+		hreq.Header.Add("User-Agent", s.Name)
+	}
 	hreq = hreq.WithContext(ctx)
 
 	hc := NewClient(u.Scheme, s.InsecureSkipVerify)

query/request.go

@@ -20,6 +20,9 @@ type Request struct {
 	// Compiler converts the query to a specification to run against the data.
 	Compiler flux.Compiler `json:"compiler"`
 
+	// Source represents the ultimate source of the request.
+	Source string `json:"source"`
+
 	// compilerMappings maps compiler types to creation methods
 	compilerMappings flux.CompilerMappings
 }

query/service_test.go

@@ -57,12 +57,13 @@ func TestRequest_JSON(t *testing.T) {
 	}{
 		{
 			name: "simple",
-			data: `{"organization_id":"aaaaaaaaaaaaaaaa","compiler":{"a":"my custom compiler"},"compiler_type":"compilerA"}`,
+			data: `{"organization_id":"aaaaaaaaaaaaaaaa","compiler":{"a":"my custom compiler"},"source":"source","compiler_type":"compilerA"}`,
 			want: query.Request{
 				OrganizationID: platformtesting.MustIDBase16("aaaaaaaaaaaaaaaa"),
 				Compiler: &compilerA{
 					A: "my custom compiler",
 				},
+				Source: "source",
 			},
 		},
 	}
@@ -94,13 +95,14 @@ func TestProxyRequest_JSON(t *testing.T) {
 	}{
 		{
 			name: "simple",
-			data: `{"request":{"organization_id":"aaaaaaaaaaaaaaaa","compiler":{"a":"my custom compiler"},"compiler_type":"compilerA"},"dialect":{"b":42},"dialect_type":"dialectB"}`,
+			data: `{"request":{"organization_id":"aaaaaaaaaaaaaaaa","compiler":{"a":"my custom compiler"},"source":"source","compiler_type":"compilerA"},"dialect":{"b":42},"dialect_type":"dialectB"}`,
 			want: query.ProxyRequest{
 				Request: query.Request{
 					OrganizationID: platformtesting.MustIDBase16("aaaaaaaaaaaaaaaa"),
 					Compiler: &compilerA{
 						A: "my custom compiler",
 					},
+					Source: "source",
 				},
 				Dialect: &dialectB{
 					B: 42,