Feat: Allow custom headers in CueX providers (#112)

Signed-off-by: Brian Kane <[email protected]>

Author: briankane

apis/cue/v1alpha1/package_types.go

@@ -56,6 +56,9 @@ const (
 type Provider struct {
 	Protocol ProviderProtocol `json:"protocol"`
 	Endpoint string           `json:"endpoint"`
+	// +optional
+	// +kubebuilder:default={}
+	Header map[string]string `json:"header,omitempty"`
 }
 
 // PackageList list for Package

apis/cue/v1alpha1/zz_generated.deepcopy.go

@@ -62,6 +62,11 @@ spec:
                 properties:
                   endpoint:
                     type: string
+                  header:
+                    additionalProperties:
+                      type: string
+                    default: {}
+                    type: object
                   protocol:
                     description: ProviderProtocol the protocol type for external Provider
                     type: string

crds/cue.oam.dev_packages.yaml

@@ -94,6 +94,9 @@ func (in *ExternalProviderFn) Call(ctx context.Context, value cue.Value) (cue.Va
 			return value, err
 		}
 		req.Header.Set("Content-Type", runtime.ContentTypeJSON)
+		for k, v := range in.Header {
+			req.Header.Set(k, v)
+		}
 		resp, err := DefaultClient.Get().Do(req.WithContext(ctx))
 		if err != nil {
 			return value, err

cue/cuex/runtime/provider.go

@@ -187,3 +187,35 @@ func TestNativeProviderFn(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, "s", s)
 }
+
+func TestProviderCustomHeader(t *testing.T) {
+	headerVal := "123"
+	headers := map[string]string{
+		"x-api-key": headerVal,
+	}
+
+	server := httptest.NewServer(http.HandlerFunc(func(writer http.ResponseWriter, request *http.Request) {
+		apiKeyFromHeader := request.Header.Get("x-api-key")
+		require.Equal(t, headerVal, apiKeyFromHeader)
+		writer.WriteHeader(200)
+		writer.Write([]byte("{}"))
+	}))
+	defer server.Close()
+
+	prd := runtime.ExternalProviderFn{
+		Provider: v1alpha1.Provider{
+			Protocol: v1alpha1.ProtocolHTTP,
+			Endpoint: server.URL,
+			Header:   headers,
+		},
+	}
+	v := cuecontext.New().CompileString(`{
+		$params: input: "value"
+		$returns?: {
+			output?: string
+			...
+		}
+	}`)
+	_, err := prd.Call(context.Background(), v)
+	require.NoError(t, err, "call to ExternalProviderFn failed")
+}