Separating different GET requests, leaning on expected response types to eliminate extra required API calls

Author: Derek Dowling

client/client.go

@@ -12,47 +12,41 @@ import (
 	"github.com/derekdowling/go-json-spec-handler"
 )
 
-// Response is a wrapper around an http.Response that allows us to perform
-// intelligent actions on them
-type Response struct {
-	*http.Response
-}
-
-// GetObject validates the HTTP response and parses out the JSON object from the
+// ParseObject validates the HTTP response and parses out the JSON object from the
 // body if possible
-func (r *Response) GetObject() (*jsh.Object, *jsh.Error) {
-	obj, objErr := buildParser(r).GetObject()
+func ParseObject(response *http.Response) (*jsh.Object, *jsh.Error) {
+	obj, objErr := buildParser(response).GetObject()
 	if objErr != nil {
 		return nil, objErr.(*jsh.Error)
 	}
 
 	return obj, nil
 }
 
-// GetList validates the HTTP response and parses out the JSON list from the
+// ParseList validates the HTTP response and parses out the JSON list from the
 // body if possible
-func (r *Response) GetList() (jsh.List, *jsh.Error) {
-	list, listErr := buildParser(r).GetList()
+func ParseList(response *http.Response) (jsh.List, *jsh.Error) {
+	list, listErr := buildParser(response).GetList()
 	if listErr != nil {
 		return nil, listErr.(*jsh.Error)
 	}
 
 	return list, nil
 }
 
-// BodyStr is a convenience function that parses the body of the response into a
-// string BUT DOESN'T close the ReadCloser
-func (r *Response) BodyStr() (string, *jsh.Error) {
+// DumpBody is a convenience function that parses the body of the response into a
+// string BUT DOESN'T close the ReadCloser. Useful for debugging.
+func DumpBody(response *http.Response) (string, *jsh.Error) {
 
-	byteData, err := ioutil.ReadAll(r.Body)
+	byteData, err := ioutil.ReadAll(response.Body)
 	if err != nil {
 		return "", jsh.ISE(fmt.Sprintf("Error attempting to read request body: %s", err.Error()))
 	}
 
 	return string(byteData), nil
 }
 
-func buildParser(response *Response) *jsh.Parser {
+func buildParser(response *http.Response) *jsh.Parser {
 	return &jsh.Parser{
 		Method:  "",
 		Headers: response.Header,
@@ -100,11 +94,11 @@ func objectToPayload(request *http.Request, object *jsh.Object) ([]byte, *jsh.Er
 
 // sendPayloadRequest is required for sending JSON payload related requests
 // because by default the http package does not set Content-Length headers
-func sendObjectRequest(request *http.Request, object *jsh.Object) (*Response, *jsh.Error) {
+func sendObjectRequest(request *http.Request, object *jsh.Object) (*jsh.Object, *http.Response, *jsh.Error) {
 
 	payload, err := objectToPayload(request, object)
 	if err != nil {
-		return nil, jsh.ISE(fmt.Sprintf("Error converting object to JSON: %s", err.Error()))
+		return nil, nil, jsh.ISE(fmt.Sprintf("Error converting object to JSON: %s", err.Error()))
 	}
 
 	// prepare payload and corresponding headers
@@ -114,11 +108,17 @@ func sendObjectRequest(request *http.Request, object *jsh.Object) (*Response, *j
 
 	client := &http.Client{}
 	response, clientErr := client.Do(request)
+
 	if clientErr != nil {
-		return nil, jsh.ISE(fmt.Sprintf(
+		return nil, nil, jsh.ISE(fmt.Sprintf(
 			"Error sending %s request: %s", request.Method, clientErr.Error(),
 		))
 	}
 
-	return &Response{response}, nil
+	object, objErr := ParseObject(response)
+	if objErr != nil {
+		return nil, response, objErr
+	}
+
+	return object, response, nil
 }

client/client_test.go

@@ -41,19 +41,19 @@ func TestClientRequest(t *testing.T) {
 	})
 }
 
-func TestClientResponse(t *testing.T) {
+func TestResponseParsing(t *testing.T) {
 
-	Convey("Client Response Tests", t, func() {
+	Convey("Response Parsing Tests", t, func() {
 
-		Convey("->GetObject()", func() {
+		Convey("->ParseObject()", func() {
 
 			obj, objErr := jsh.NewObject("123", "test", map[string]string{"test": "test"})
 			So(objErr, ShouldBeNil)
 			response, err := mockObjectResponse(obj)
 			So(err, ShouldBeNil)
 
 			Convey("should parse successfully", func() {
-				respObj, err := response.GetObject()
+				respObj, err := ParseObject(response)
 				So(err, ShouldBeNil)
 				So(respObj, ShouldNotBeNil)
 			})
@@ -71,7 +71,7 @@ func TestClientResponse(t *testing.T) {
 			So(err, ShouldBeNil)
 
 			Convey("should parse successfully", func() {
-				respObj, err := response.GetList()
+				respObj, err := ParseList(response)
 				So(err, ShouldBeNil)
 				So(respObj, ShouldNotBeNil)
 			})

client/get.go

@@ -8,34 +8,60 @@ import (
 	"github.com/derekdowling/go-json-spec-handler"
 )
 
-// Get allows a user to make an outbound GET /resources(/:id) request.
-//
-// For a GET request that retrieves multiple resources, pass an empty string for
-// the id parameter:
-//
-//  GET "http://apiserver/users
-//	resp, err := jsh.Get("http://apiserver", "user", "")
-//	list, err := resp.GetList()
-//
-// For a GET request on a specific attribute:
-//
-//  GET "http://apiserver/users/2
-//	resp, err := jsh.Get("http://apiserver", "user", "2")
-//	obj := resp.GetObject()
-//
-func Get(urlStr string, resourceType string, id string) (*Response, *jsh.Error) {
+// GetObject allows a user to make an outbound GET /resourceTypes/:id
+func GetObject(urlStr string, resourceType string, id string) (*jsh.Object, *http.Response, *jsh.Error) {
+	if id == "" {
+		return nil, nil, jsh.SpecificationError("ID cannot be empty for GetObject request type")
+	}
 
 	u, err := url.Parse(urlStr)
 	if err != nil {
-		return nil, jsh.ISE(fmt.Sprintf("Error parsing URL: %s", err.Error()))
+		return nil, nil, jsh.ISE(fmt.Sprintf("Error parsing URL: %s", err.Error()))
 	}
 
 	setIDPath(u, resourceType, id)
 
-	response, err := http.Get(u.String())
+	response, getErr := Get(u.String())
+	if err != nil {
+		return nil, nil, getErr
+	}
+
+	object, objectErr := ParseObject(response)
+	if objectErr != nil {
+		return nil, response, objectErr
+	}
+
+	return object, response, nil
+}
+
+// GetList prepares an outbound request for /resourceTypes expecting a list return value.
+func GetList(urlStr string, resourceType string) (jsh.List, *http.Response, *jsh.Error) {
+	u, err := url.Parse(urlStr)
+	if err != nil {
+		return nil, nil, jsh.ISE(fmt.Sprintf("Error parsing URL: %s", err.Error()))
+	}
+
+	setPath(u, resourceType)
+
+	response, getErr := Get(u.String())
+	if err != nil {
+		return nil, nil, getErr
+	}
+
+	list, listErr := ParseList(response)
+	if listErr != nil {
+		return nil, response, listErr
+	}
+
+	return list, response, nil
+}
+
+// Get performs a Get request for a given URL and returns a basic Response type
+func Get(urlStr string) (*http.Response, *jsh.Error) {
+	response, err := http.Get(urlStr)
 	if err != nil {
 		return nil, jsh.ISE(fmt.Sprintf("Error performing GET request: %s", err.Error()))
 	}
 
-	return &Response{response}, nil
+	return response, nil
 }

client/get_test.go

@@ -1,6 +1,7 @@
 package jsc
 
 import (
+	"net/http"
 	"net/http/httptest"
 	"testing"
 
@@ -17,21 +18,24 @@ func TestGet(t *testing.T) {
 		baseURL := server.URL
 
 		Convey("->Get()", func() {
+			resp, err := Get(baseURL + "/tests/1")
+			So(err, ShouldBeNil)
+			So(resp.StatusCode, ShouldEqual, http.StatusOK)
+		})
 
-			Convey("should handle an object listing request", func() {
-				resp, err := Get(baseURL, "test", "")
-				So(err, ShouldBeNil)
+		Convey("->GetList()", func() {
 
-				list, err := resp.GetList()
+			Convey("should handle an object listing request", func() {
+				list, _, err := GetList(baseURL, "test")
 				So(err, ShouldBeNil)
 				So(len(list), ShouldEqual, 1)
 			})
+		})
 
-			Convey("should handle a specific object request", func() {
-				resp, err := Get(baseURL, "test", "1")
-				So(err, ShouldBeNil)
+		Convey("->GetObject()", func() {
 
-				obj, err := resp.GetObject()
+			Convey("should handle a specific object request", func() {
+				obj, _, err := GetObject(baseURL, "test", "1")
 				So(err, ShouldBeNil)
 				So(obj.ID, ShouldEqual, "1")
 			})

client/patch.go

@@ -15,18 +15,18 @@ import (
 //  resp, _ := jsc.Patch("http://postap.com", obj)
 //  updatedObj, _ := resp.GetObject()
 //
-func Patch(urlStr string, object *jsh.Object) (*Response, *jsh.Error) {
+func Patch(urlStr string, object *jsh.Object) (*jsh.Object, *http.Response, *jsh.Error) {
 
 	u, err := url.Parse(urlStr)
 	if err != nil {
-		return nil, jsh.ISE(fmt.Sprintf("Error parsing URL: %s", err.Error()))
+		return nil, nil, jsh.ISE(fmt.Sprintf("Error parsing URL: %s", err.Error()))
 	}
 
 	setIDPath(u, object.Type, object.ID)
 
 	request, err := http.NewRequest("PATCH", u.String(), nil)
 	if err != nil {
-		return nil, jsh.ISE(fmt.Sprintf("Error creating PATCH request: %s", err.Error()))
+		return nil, nil, jsh.ISE(fmt.Sprintf("Error creating PATCH request: %s", err.Error()))
 	}
 
 	return sendObjectRequest(request, object)

client/post.go

@@ -14,19 +14,19 @@ import (
 //	resp, _ := jsh.Post("http://apiserver", obj)
 //	createdObj := resp.GetObject()
 //
-func Post(urlStr string, object *jsh.Object) (*Response, *jsh.Error) {
+func Post(urlStr string, object *jsh.Object) (*jsh.Object, *http.Response, *jsh.Error) {
 
 	u, err := url.Parse(urlStr)
 	if err != nil {
-		return nil, jsh.ISE(fmt.Sprintf("Error parsing URL: %s", err.Error()))
+		return nil, nil, jsh.ISE(fmt.Sprintf("Error parsing URL: %s", err.Error()))
 	}
 
 	// ghetto pluralization, fix when it becomes an issue
 	setPath(u, object.Type)
 
 	request, err := http.NewRequest("POST", u.String(), nil)
 	if err != nil {
-		return nil, jsh.ISE(fmt.Sprintf("Error building POST request: %s", err.Error()))
+		return nil, nil, jsh.ISE(fmt.Sprintf("Error building POST request: %s", err.Error()))
 	}
 
 	return sendObjectRequest(request, object)

client/test_util.go

@@ -8,7 +8,7 @@ import (
 	"github.com/derekdowling/go-json-spec-handler"
 )
 
-func mockObjectResponse(object *jsh.Object) (*Response, error) {
+func mockObjectResponse(object *jsh.Object) (*http.Response, error) {
 	object.ID = "1"
 
 	url := &url.URL{Host: "test"}
@@ -29,7 +29,7 @@ func mockObjectResponse(object *jsh.Object) (*Response, error) {
 	return recorderToResponse(recorder), nil
 }
 
-func mockListResponse(list jsh.List) (*Response, error) {
+func mockListResponse(list jsh.List) (*http.Response, error) {
 
 	url := &url.URL{Host: "test"}
 	setPath(url, list[0].Type)
@@ -49,10 +49,10 @@ func mockListResponse(list jsh.List) (*Response, error) {
 	return recorderToResponse(recorder), nil
 }
 
-func recorderToResponse(recorder *httptest.ResponseRecorder) *Response {
-	return &Response{&http.Response{
+func recorderToResponse(recorder *httptest.ResponseRecorder) *http.Response {
+	return &http.Response{
 		StatusCode: recorder.Code,
 		Body:       jsh.CreateReadCloser(recorder.Body.Bytes()),
 		Header:     recorder.Header(),
-	}}
+	}
 }