Merge pull request concourse#9011 from Pix4D/go-concourse-connection-…

…client-improve-error-msg

go-concourse:connection client prints response body to the end user

go-concourse/concourse/internal/connection.go

@@ -200,7 +200,8 @@ func (connection *connection) populateResponse(response *http.Response, returnRe
 	}
 
 	if response.StatusCode == http.StatusForbidden {
-		return ErrForbidden
+		body, _ := io.ReadAll(response.Body)
+		return ForbiddenError{Reason: string(body)}
 	}
 
 	if response.StatusCode < 200 || response.StatusCode >= 300 {

go-concourse/concourse/internal/connection_test.go

@@ -351,6 +351,31 @@ var _ = Describe("ATC Connection", func() {
 				})
 			})
 
+			Describe("403 response", func() {
+				BeforeEach(func() {
+					atcServer = ghttp.NewServer()
+					connection = NewConnection(atcServer.URL(), nil, tracing)
+					atcServer.AppendHandlers(
+						ghttp.CombineHandlers(
+							ghttp.VerifyRequest("DELETE", "/api/v1/teams/main/pipelines/foo"),
+							ghttp.RespondWith(http.StatusForbidden, "problem"),
+						),
+					)
+				})
+				It("returns back ForbiddenError", func() {
+					err := connection.Send(Request{
+						RequestName: atc.DeletePipeline,
+						Params: rata.Params{
+							"pipeline_name": "foo",
+							"team_name":     atc.DefaultTeamName,
+						},
+					}, nil)
+					fe, ok := err.(ForbiddenError)
+					Expect(ok).To(BeTrue())
+					Expect(fe.Reason).To(Equal("problem"))
+				})
+			})
+
 			Describe("404 response", func() {
 				Context("when the response does not contain JSONAPI errors", func() {
 					BeforeEach(func() {