fix(errors): support error checking methods for new problem structures (

#212) Adds previously returned errors to the "Unwrap" chain for checking against in methods like "errors.Is()" and adds an implementation of "Is" to Problem types to enable equality checking against problems. Also, adds all of the previously returned errors back into the problem structures to maintain full compatibility with downstream code. Signed-off-by: Dustin Popp <dpopp07@gmail.com>
IBM · Mar 20, 2024 · 65eb01d · 65eb01d
1 parent 0f33aee
commit 65eb01d
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Showing 18 changed files with 159 additions and 90 deletions.
diff --git a/core/base_service.go b/core/base_service.go
@@ -409,11 +409,10 @@ func (service *BaseService) Request(req *http.Request, result interface{}) (deta
 	httpResponse, err = service.Client.Do(req)
 
 	if err != nil {
-		errMsg := err.Error()
 		if strings.Contains(err.Error(), SSL_CERTIFICATION_ERROR) {
-			errMsg = ERRORMSG_SSL_VERIFICATION_FAILED + "\n" + errMsg
+			err = fmt.Errorf(ERRORMSG_SSL_VERIFICATION_FAILED + "\n" + err.Error())
 		}
-		err = SDKErrorf(nil, errMsg, "no-connection-made", getComponentInfo())
+		err = SDKErrorf(err, "", "no-connection-made", getComponentInfo())
 		return
 	}
 
@@ -452,8 +451,8 @@ func (service *BaseService) Request(req *http.Request, result interface{}) (deta
 			defer httpResponse.Body.Close() // #nosec G307
 			responseBody, readErr := io.ReadAll(httpResponse.Body)
 			if readErr != nil {
-				errMsg := fmt.Sprintf(ERRORMSG_READ_RESPONSE_BODY, readErr.Error())
-				err = SDKErrorf(nil, errMsg, "cant-read-success-res-body", getComponentInfo())
+				err = fmt.Errorf(ERRORMSG_READ_RESPONSE_BODY, readErr.Error())
+				err = SDKErrorf(err, "", "cant-read-success-res-body", getComponentInfo())
 				return
 			}
 
@@ -469,8 +468,8 @@ func (service *BaseService) Request(req *http.Request, result interface{}) (deta
 				if decodeErr != nil {
 					// Error decoding the response body.
 					// Return the response body in RawResult, along with an error.
-					errMsg := fmt.Sprintf(ERRORMSG_UNMARSHAL_RESPONSE_BODY, decodeErr.Error())
-					err = SDKErrorf(nil, errMsg, "res-body-decode-error", getComponentInfo())
+					err = fmt.Errorf(ERRORMSG_UNMARSHAL_RESPONSE_BODY, decodeErr.Error())
+					err = SDKErrorf(err, "", "res-body-decode-error", getComponentInfo())
 					detailedResponse.RawResult = responseBody
 					return
 				}
@@ -500,8 +499,8 @@ func (service *BaseService) Request(req *http.Request, result interface{}) (deta
 				// At this point, we don't know how to set the result field, so we have to return an error.
 				// But make sure we save the bytes we read in the DetailedResponse for debugging purposes
 				detailedResponse.Result = responseBody
-				errMsg := fmt.Sprintf(ERRORMSG_UNEXPECTED_RESPONSE, contentType, resultType)
-				err = SDKErrorf(nil, errMsg, "unparsable-result-field", getComponentInfo())
+				err = fmt.Errorf(ERRORMSG_UNEXPECTED_RESPONSE, contentType, resultType)
+				err = SDKErrorf(err, "", "unparsable-result-field", getComponentInfo())
 				return
 			}
 		}
@@ -602,7 +601,7 @@ type Error struct {
 func decodeAsMap(byteBuffer []byte) (result map[string]interface{}, err error) {
 	err = json.NewDecoder(bytes.NewReader(byteBuffer)).Decode(&result)
 	if err != nil {
-		err = SDKErrorf(nil, err.Error(), "decode-error", getComponentInfo())
+		err = SDKErrorf(err, "", "decode-error", getComponentInfo())
 	}
 	return
 }
@@ -836,17 +835,17 @@ func IBMCloudSDKRetryPolicy(ctx context.Context, resp *http.Response, err error)
 		if v, ok := err.(*url.Error); ok {
 			// Don't retry if the error was due to too many redirects.
 			if redirectsErrorRe.MatchString(v.Error()) {
-				return false, SDKErrorf(nil, v.Error(), "too-many-redirects", getComponentInfo())
+				return false, SDKErrorf(v, "", "too-many-redirects", getComponentInfo())
 			}
 
 			// Don't retry if the error was due to an invalid protocol scheme.
 			if schemeErrorRe.MatchString(v.Error()) {
-				return false, SDKErrorf(nil, v.Error(), "invalid-scheme", getComponentInfo())
+				return false, SDKErrorf(v, "", "invalid-scheme", getComponentInfo())
 			}
 
 			// Don't retry if the error was due to TLS cert verification failure.
 			if _, ok := v.Err.(x509.UnknownAuthorityError); ok {
-				return false, SDKErrorf(nil, v.Error(), "cert-failure", getComponentInfo())
+				return false, SDKErrorf(v, "", "cert-failure", getComponentInfo())
 			}
 		}
 

diff --git a/core/container_authenticator.go b/core/container_authenticator.go
@@ -496,8 +496,8 @@ func (authenticator *ContainerAuthenticator) retrieveCRToken() (crToken string,
 	}
 
 	if err != nil {
-		errMsg := fmt.Sprintf(ERRORMSG_UNABLE_RETRIEVE_CRTOKEN, err.Error())
-		sdkErr := SDKErrorf(nil, errMsg, "no-cr-token", getComponentInfo())
+		err = fmt.Errorf(ERRORMSG_UNABLE_RETRIEVE_CRTOKEN, err.Error())
+		sdkErr := SDKErrorf(err, "", "no-cr-token", getComponentInfo())
 		GetLogger().Debug(sdkErr.GetDebugMessage())
 		err = sdkErr
 		return
@@ -514,8 +514,8 @@ func (authenticator *ContainerAuthenticator) readFile(filename string) (crToken
 	var bytes []byte
 	bytes, err = os.ReadFile(filename) // #nosec G304
 	if err != nil {
-		err = SDKErrorf(nil, err.Error(), "read-file-error", getComponentInfo())
-		GetLogger().Debug(err.Error())
+		err = SDKErrorf(err, "", "read-file-error", getComponentInfo())
+		GetLogger().Debug(err.(*SDKProblem).GetDebugMessage())
 		return
 	}
 

diff --git a/core/cp4d_authenticator.go b/core/cp4d_authenticator.go
@@ -330,7 +330,7 @@ func (authenticator *CloudPakForDataAuthenticator) requestToken() (tokenResponse
 	GetLogger().Debug("Invoking CP4D token service operation: %s", builder.URL)
 	resp, err := authenticator.client().Do(req)
 	if err != nil {
-		err = SDKErrorf(nil, err.Error(), "cp4d-request-error", getComponentInfo())
+		err = SDKErrorf(err, "", "cp4d-request-error", getComponentInfo())
 		return
 	}
 	GetLogger().Debug("Returned from CP4D token service operation, received status code %d", resp.StatusCode)
@@ -369,8 +369,8 @@ func (authenticator *CloudPakForDataAuthenticator) requestToken() (tokenResponse
 	err = json.NewDecoder(resp.Body).Decode(tokenResponse)
 	defer resp.Body.Close() // #nosec G307
 	if err != nil {
-		errMsg := fmt.Sprintf(ERRORMSG_UNMARSHAL_AUTH_RESPONSE, err.Error())
-		err = SDKErrorf(nil, errMsg, "cp4d-res-unmarshal-error", getComponentInfo())
+		err = fmt.Errorf(ERRORMSG_UNMARSHAL_AUTH_RESPONSE, err.Error())
+		err = SDKErrorf(err, "", "cp4d-res-unmarshal-error", getComponentInfo())
 		tokenResponse = nil
 		return
 	}

diff --git a/core/datetime.go b/core/datetime.go
@@ -83,7 +83,7 @@ func ParseDate(dateString string) (fmtDate strfmt.Date, err error) {
 	if err == nil {
 		fmtDate = strfmt.Date(formattedTime)
 	} else {
-		err = SDKErrorf(nil, err.Error(), "date-parse-error", getComponentInfo())
+		err = SDKErrorf(err, "", "date-parse-error", getComponentInfo())
 	}
 	return
 }
@@ -93,7 +93,7 @@ func ParseDate(dateString string) (fmtDate strfmt.Date, err error) {
 func ParseDateTime(dateString string) (strfmt.DateTime, error) {
 	dt, err := strfmt.ParseDateTime(dateString)
 	if err != nil {
-		err = SDKErrorf(nil, err.Error(), "datetime-parse-error", getComponentInfo())
+		err = SDKErrorf(err, "", "datetime-parse-error", getComponentInfo())
 	}
 	return dt, err
 }
diff --git a/core/file_with_metadata.go b/core/file_with_metadata.go
@@ -58,7 +58,7 @@ func UnmarshalFileWithMetadata(m map[string]json.RawMessage, result interface{})
 	}
 	data, err = os.Open(pathToData) // #nosec G304
 	if err != nil {
-		err = SDKErrorf(nil, err.Error(), "file-open-error", getComponentInfo())
+		err = SDKErrorf(err, "", "file-open-error", getComponentInfo())
 		return
 	}
 	obj.Data = data

diff --git a/core/gzip.go b/core/gzip.go
@@ -42,7 +42,7 @@ func NewGzipCompressionReader(uncompressedReader io.Reader) (io.Reader, error) {
 		// to the pipe only when the pipe reader is called to retrieve more bytes.
 		_, err := io.Copy(compressedWriter, uncompressedReader)
 		if err != nil {
-			sdkErr := SDKErrorf(nil, err.Error(), "compression-failed", getComponentInfo())
+			sdkErr := SDKErrorf(err, "", "compression-failed", getComponentInfo())
 			_ = pipeWriter.CloseWithError(sdkErr)
 		}
 	}()
@@ -54,7 +54,7 @@ func NewGzipCompressionReader(uncompressedReader io.Reader) (io.Reader, error) {
 func NewGzipDecompressionReader(compressedReader io.Reader) (io.Reader, error) {
 	res, err := gzip.NewReader(compressedReader)
 	if err != nil {
-		err = SDKErrorf(nil, err.Error(), "decompress-read-error", getComponentInfo())
+		err = SDKErrorf(err, "", "decompress-read-error", getComponentInfo())
 	}
 	return res, err
 }
diff --git a/core/http_problem.go b/core/http_problem.go
@@ -57,6 +57,13 @@ func (e *HTTPProblem) GetID() string {
 	return CreateIDHash("http", e.GetBaseSignature(), e.OperationID, fmt.Sprint(e.Response.GetStatusCode()))
 }
 
+// Is allows an HTTPProblem instance to be compared against another error for equality.
+// An HTTPProblem is considered equal to another error if 1) the error is also a Problem and
+// 2) it has the same ID (i.e. it is the same problem scenario).
+func (e *HTTPProblem) Is(target error) bool {
+	return is(target, e.GetID())
+}
+
 func (e *HTTPProblem) getErrorCode() string {
 	// If the error response was a standard JSON body, the result will
 	// be a map and we can do a decent job of guessing the code.

diff --git a/core/http_problem_test.go b/core/http_problem_test.go
@@ -15,6 +15,7 @@ package core
 // limitations under the License.
 
 import (
+	"errors"
 	"net/http"
 	"testing"
 
@@ -220,6 +221,17 @@ func TestHTTPProblemGetErrorCode(t *testing.T) {
 	assert.Equal(t, "invalid-input", httpProb.getErrorCode())
 }
 
+func TestHTTPProblemIsWithProblem(t *testing.T) {
+	firstProb := httpErrorf("Bad request", getPopulatedDetailedResponse())
+	EnrichHTTPProblem(firstProb, "create_resource", NewProblemComponent("service", "1.0.0"))
+
+	secondProb := httpErrorf("Invalid input", getPopulatedDetailedResponse())
+	EnrichHTTPProblem(secondProb, "create_resource", NewProblemComponent("service", "1.2.3"))
+
+	assert.NotEqual(t, firstProb, secondProb)
+	assert.True(t, errors.Is(firstProb, secondProb))
+}
+
 func TestHTTPErrorf(t *testing.T) {
 	message := "Bad request"
 	httpProb := httpErrorf(message, getPopulatedDetailedResponse())

diff --git a/core/iam_authenticator.go b/core/iam_authenticator.go
@@ -463,7 +463,7 @@ func (authenticator *IamAuthenticator) RequestToken() (*IamTokenServerResponse,
 	GetLogger().Debug("Invoking IAM 'get token' operation: %s", builder.URL)
 	resp, err := authenticator.client().Do(req)
 	if err != nil {
-		err = SDKErrorf(nil, err.Error(), "request-error", getComponentInfo())
+		err = SDKErrorf(err, "", "request-error", getComponentInfo())
 		return nil, err
 	}
 	GetLogger().Debug("Returned from IAM 'get token' operation, received status code %d", resp.StatusCode)

diff --git a/core/ibm_problem.go b/core/ibm_problem.go
@@ -74,6 +74,13 @@ type IBMProblem struct {
 	// causedBy allows for the storage of a problem from a previous component,
 	// if there is one.
 	causedBy Problem
+
+	// nativeCausedBy allows for the storage of an error that is the cause of
+	// the problem instance but is not a part of the official chain of problem
+	// types. By including these errors in the "Unwrap" chain, the problem type
+	// changes become compatible with downstream code that uses error checking
+	// methods like "Is" and "As".
+	nativeCausedBy error
 }
 
 // Error returns the problem's message and implements the native
@@ -109,12 +116,21 @@ func (e *IBMProblem) GetCausedBy() Problem {
 // it does not include the error instance the method is called on - that is
 // looked at separately by the "errors" package in functions like "As".
 func (e *IBMProblem) Unwrap() []error {
+	var errs []error
+
+	// Include native (i.e. non-Problem) caused by errors in the
+	// chain for compatibility with respect to downstream methods
+	// like "errors.Is" or "errors.As".
+	if e.nativeCausedBy != nil {
+		errs = append(errs, e.nativeCausedBy)
+	}
+
 	causedBy := e.GetCausedBy()
 	if causedBy == nil {
-		return nil
+		return errs
 	}
 
-	errs := []error{causedBy}
+	errs = append(errs, causedBy)
 
 	var toUnwrap interface{ Unwrap() []error }
 	if errors.As(causedBy, &toUnwrap) {
@@ -144,6 +160,8 @@ func ibmProblemf(err error, severity problemSeverity, component *ProblemComponen
 	var causedBy Problem
 	if errors.As(err, &causedBy) {
 		newError.causedBy = causedBy
+	} else {
+		newError.nativeCausedBy = err
 	}
 
 	return newError

diff --git a/core/jwt_utils.go b/core/jwt_utils.go
@@ -47,7 +47,8 @@ func parseJWT(tokenString string) (claims *coreJWTClaims, err error) {
 	claims = &coreJWTClaims{}
 	err = json.Unmarshal(claimBytes, claims)
 	if err != nil {
-		err = SDKErrorf(nil, fmt.Sprintf("error unmarshalling token: %s", err.Error()), "bad-token", getComponentInfo())
+		err = fmt.Errorf("error unmarshalling token: %s", err.Error())
+		err = SDKErrorf(err, "", "bad-token", getComponentInfo())
 		return
 	}
 
@@ -63,7 +64,7 @@ func decodeSegment(seg string) ([]byte, error) {
 
 	res, err := base64.URLEncoding.DecodeString(seg)
 	if err != nil {
-		err = SDKErrorf(nil, fmt.Sprintf("error decoding claims segment: %s", err.Error()), "bad-claim-seg", getComponentInfo())
+		err = SDKErrorf(err, fmt.Sprintf("error decoding claims segment: %s", err.Error()), "bad-claim-seg", getComponentInfo())
 	}
 	return res, err
 }
diff --git a/core/mcsp_authenticator.go b/core/mcsp_authenticator.go
@@ -304,7 +304,7 @@ func (authenticator *MCSPAuthenticator) RequestToken() (*MCSPTokenServerResponse
 	GetLogger().Debug("Invoking MCSP 'get token' operation: %s", builder.URL)
 	resp, err := authenticator.client().Do(req)
 	if err != nil {
-		err = SDKErrorf(nil, err.Error(), "request-error", getComponentInfo())
+		err = SDKErrorf(err, "", "request-error", getComponentInfo())
 		return nil, err
 	}
 	GetLogger().Debug("Returned from MCSP 'get token' operation, received status code %d", resp.StatusCode)

diff --git a/core/problem_utils.go b/core/problem_utils.go
@@ -17,6 +17,7 @@ package core
 import (
 	"crypto/sha256"
 	"encoding/hex"
+	"errors"
 	"fmt"
 	"strings"
 
@@ -55,3 +56,12 @@ func getProblemInfoAsYAML(orderedMaps *OrderedMaps) string {
 func getComponentInfo() *ProblemComponent {
 	return NewProblemComponent(MODULE_NAME, __VERSION__)
 }
+
+// is provides a simple utility function that assists problem types
+// implement an "Is" function for checking error equality. Error types
+// are treated as equivalent if they are both Problem types and their
+// IDs match.
+func is(target error, id string) bool {
+	var problem Problem
+	return errors.As(target, &problem) && problem.GetID() == id
+}
diff --git a/core/request_builder.go b/core/request_builder.go
@@ -111,8 +111,8 @@ func (requestBuilder *RequestBuilder) ConstructHTTPURL(serviceURL string, pathSe
 
 	URL, err := url.Parse(serviceURL)
 	if err != nil {
-		errMsg := fmt.Sprintf(ERRORMSG_SERVICE_URL_INVALID, err.Error())
-		return requestBuilder, SDKErrorf(nil, errMsg, "bad-url", getComponentInfo())
+		err := fmt.Errorf(ERRORMSG_SERVICE_URL_INVALID, err.Error())
+		return requestBuilder, SDKErrorf(err, "", "bad-url", getComponentInfo())
 	}
 
 	for i, pathSegment := range pathSegments {
@@ -122,8 +122,8 @@ func (requestBuilder *RequestBuilder) ConstructHTTPURL(serviceURL string, pathSe
 
 		if pathParameters != nil && i < len(pathParameters) {
 			if pathParameters[i] == "" {
-				errMsg := fmt.Sprintf(ERRORMSG_PATH_PARAM_EMPTY, fmt.Sprintf("[%d]", i))
-				return requestBuilder, SDKErrorf(nil, errMsg, "empty-path-param", getComponentInfo())
+				err := fmt.Errorf(ERRORMSG_PATH_PARAM_EMPTY, fmt.Sprintf("[%d]", i))
+				return requestBuilder, SDKErrorf(err, "", "empty-path-param", getComponentInfo())
 			}
 			URL.Path += "/" + pathParameters[i]
 		}
@@ -186,8 +186,8 @@ func (requestBuilder *RequestBuilder) ResolveRequestURL(serviceURL string, path
 
 	URL, err := url.Parse(urlString)
 	if err != nil {
-		errMsg := fmt.Sprintf(ERRORMSG_SERVICE_URL_INVALID, err.Error())
-		return requestBuilder, SDKErrorf(nil, errMsg, "bad-url", getComponentInfo())
+		err = fmt.Errorf(ERRORMSG_SERVICE_URL_INVALID, err.Error())
+		return requestBuilder, SDKErrorf(err, "", "bad-url", getComponentInfo())
 	}
 
 	requestBuilder.URL = URL
@@ -231,8 +231,8 @@ func (requestBuilder *RequestBuilder) SetBodyContentJSON(bodyContent interface{}
 	requestBuilder.Body = new(bytes.Buffer)
 	err := json.NewEncoder(requestBuilder.Body.(io.Writer)).Encode(bodyContent)
 	if err != nil {
-		errMsg := fmt.Sprintf("Could not encode JSON body:\n%s", err.Error())
-		err = SDKErrorf(nil, errMsg, "bad-encode", getComponentInfo())
+		err = fmt.Errorf("Could not encode JSON body:\n%s", err.Error())
+		err = SDKErrorf(err, "", "bad-encode", getComponentInfo())
 	}
 	return requestBuilder, err
 }
@@ -265,7 +265,7 @@ func createFormFile(formWriter *multipart.Writer, fieldname string, filename str
 
 	res, err := formWriter.CreatePart(h)
 	if err != nil {
-		err = SDKErrorf(nil, err.Error(), "create-part-error", getComponentInfo())
+		err = SDKErrorf(err, "", "create-part-error", getComponentInfo())
 	}
 	return res, err
 }
@@ -494,12 +494,16 @@ func (requestBuilder *RequestBuilder) SetBodyContent(contentType string, jsonCon
 		// which should be a "string", "*string" or an "io.Reader"
 		if str, ok := nonJSONContent.(string); ok {
 			builder, err = requestBuilder.SetBodyContentString(str)
+			err = RepurposeSDKProblem(err, "set-body-string-error")
 		} else if strPtr, ok := nonJSONContent.(*string); ok {
 			builder, err = requestBuilder.SetBodyContentString(*strPtr)
+			err = RepurposeSDKProblem(err, "set-body-strptr-error")
 		} else if stream, ok := nonJSONContent.(io.Reader); ok {
 			builder, err = requestBuilder.SetBodyContentStream(stream)
+			err = RepurposeSDKProblem(err, "set-body-reader-error")
 		} else if stream, ok := nonJSONContent.(*io.ReadCloser); ok {
 			builder, err = requestBuilder.SetBodyContentStream(*stream)
+			err = RepurposeSDKProblem(err, "set-body-readerptr-error")
 		} else {
 			builder = requestBuilder
 			errMsg := fmt.Sprintf("Invalid type for non-JSON body content: %s", reflect.TypeOf(nonJSONContent).String())

diff --git a/core/sdk_problem.go b/core/sdk_problem.go
@@ -55,6 +55,13 @@ func (e *SDKProblem) GetID() string {
 	return CreateIDHash("sdk", e.GetBaseSignature(), e.Function)
 }
 
+// Is allows an SDKProblem instance to be compared against another error for equality.
+// An SDKProblem is considered equal to another error if 1) the error is also a Problem and
+// 2) it has the same ID (i.e. it is the same problem scenario).
+func (e *SDKProblem) Is(target error) bool {
+	return is(target, e.GetID())
+}
+
 // GetConsoleOrderedMaps returns an ordered-map representation
 // of an SDKProblem instance suited for a console message.
 func (e *SDKProblem) GetConsoleOrderedMaps() *OrderedMaps {