Add ability to pass in substitution args into an Error

Signed-off-by: Doug Davis <dug@us.ibm.com>
This commit is contained in:
Doug Davis 2015-06-17 17:39:27 -07:00
parent 2451dd1c32
commit 94e2e9f4a0
5 changed files with 111 additions and 40 deletions

View file

@ -69,20 +69,28 @@ func (ec *ErrorCode) UnmarshalText(text []byte) error {
// WithDetail creates a new Error struct based on the passed-in info and // WithDetail creates a new Error struct based on the passed-in info and
// set the Detail property appropriately // set the Detail property appropriately
func (ec ErrorCode) WithDetail(detail interface{}) Error { func (ec ErrorCode) WithDetail(detail interface{}) Error {
if err, ok := detail.(error); ok {
detail = err.Error()
}
return Error{ return Error{
Code: ec, Code: ec,
Detail: detail, Message: ec.Message(),
} }.WithDetail(detail)
}
// WithArgs creates a new Error struct and sets the Args slice
func (ec ErrorCode) WithArgs(args ...interface{}) Error {
return Error{
Code: ec,
Message: ec.Message(),
}.WithArgs(args...)
} }
// Error provides a wrapper around ErrorCode with extra Details provided. // Error provides a wrapper around ErrorCode with extra Details provided.
type Error struct { type Error struct {
Code ErrorCode `json:"code"` Code ErrorCode `json:"code"`
Detail interface{} `json:"detail,omitempty"` Message string `json:"message"`
Detail interface{} `json:"detail,omitempty"`
// TODO(duglin): See if we need an "args" property so we can do the
// variable substitution right before showing the message to the user
} }
// ErrorCode returns the ID/Value of this Error // ErrorCode returns the ID/Value of this Error
@ -97,9 +105,24 @@ func (e Error) Error() string {
e.Code.Message()) e.Code.Message())
} }
// Message returned the human-readable error message for this Error // WithDetail will return a new Error, based on the current one, but with
func (e Error) Message() string { // some Detail info added
return e.Code.Message() func (e Error) WithDetail(detail interface{}) Error {
return Error{
Code: e.Code,
Message: e.Message,
Detail: detail,
}
}
// WithArgs uses the passed-in list of interface{} as the substitution
// variables in the Error's Message string, but returns a new Error
func (e Error) WithArgs(args ...interface{}) Error {
return Error{
Code: e.Code,
Message: fmt.Sprintf(e.Code.Message(), args...),
Detail: e.Detail,
}
} }
// ErrorDescriptor provides relevant information about a given error code. // ErrorDescriptor provides relevant information about a given error code.
@ -160,20 +183,11 @@ func (errs Errors) Len() int {
return len(errs) return len(errs)
} }
// jsonError extends Error with 'Message' so that we can include the
// error text, just in case the receiver of the JSON doesn't have this
// particular ErrorCode registered
type jsonError struct {
Code ErrorCode `json:"code"`
Message string `json:"message"`
Detail interface{} `json:"detail,omitempty"`
}
// MarshalJSON converts slice of error, ErrorCode or Error into a // MarshalJSON converts slice of error, ErrorCode or Error into a
// slice of Error - then serializes // slice of Error - then serializes
func (errs Errors) MarshalJSON() ([]byte, error) { func (errs Errors) MarshalJSON() ([]byte, error) {
var tmpErrs struct { var tmpErrs struct {
Errors []jsonError `json:"errors,omitempty"` Errors []Error `json:"errors,omitempty"`
} }
for _, daErr := range errs { for _, daErr := range errs {
@ -189,9 +203,16 @@ func (errs Errors) MarshalJSON() ([]byte, error) {
} }
tmpErrs.Errors = append(tmpErrs.Errors, jsonError{ // If the Error struct was setup and they forgot to set the
// Message field (meaning its "") then grab it from the ErrCode
msg := err.Message
if msg == "" {
msg = err.Code.Message()
}
tmpErrs.Errors = append(tmpErrs.Errors, Error{
Code: err.Code, Code: err.Code,
Message: err.Message(), Message: msg,
Detail: err.Detail, Detail: err.Detail,
}) })
} }
@ -203,7 +224,7 @@ func (errs Errors) MarshalJSON() ([]byte, error) {
// Error or ErrorCode // Error or ErrorCode
func (errs *Errors) UnmarshalJSON(data []byte) error { func (errs *Errors) UnmarshalJSON(data []byte) error {
var tmpErrs struct { var tmpErrs struct {
Errors []jsonError Errors []Error
} }
if err := json.Unmarshal(data, &tmpErrs); err != nil { if err := json.Unmarshal(data, &tmpErrs); err != nil {
@ -212,14 +233,17 @@ func (errs *Errors) UnmarshalJSON(data []byte) error {
var newErrs Errors var newErrs Errors
for _, daErr := range tmpErrs.Errors { for _, daErr := range tmpErrs.Errors {
if daErr.Detail == nil { // If Message is empty or exactly matches the Code's message string
// then just use the Code, no need for a full Error struct
if daErr.Detail == nil && (daErr.Message == "" || daErr.Message == daErr.Code.Message()) {
// Error's w/o details get converted to ErrorCode // Error's w/o details get converted to ErrorCode
newErrs = append(newErrs, daErr.Code) newErrs = append(newErrs, daErr.Code)
} else { } else {
// Error's w/ details are untouched // Error's w/ details are untouched
newErrs = append(newErrs, Error{ newErrs = append(newErrs, Error{
Code: daErr.Code, Code: daErr.Code,
Detail: daErr.Detail, Message: daErr.Message,
Detail: daErr.Detail,
}) })
} }
} }

View file

@ -76,12 +76,21 @@ var ErrorCodeTest2 = Register("v2.errors", ErrorDescriptor{
HTTPStatusCode: http.StatusNotFound, HTTPStatusCode: http.StatusNotFound,
}) })
var ErrorCodeTest3 = Register("v2.errors", ErrorDescriptor{
Value: "TEST3",
Message: "Sorry %q isn't valid",
Description: `Just a test message #3.`,
HTTPStatusCode: http.StatusNotFound,
})
func TestErrorsManagement(t *testing.T) { func TestErrorsManagement(t *testing.T) {
var errs Errors var errs Errors
errs = append(errs, ErrorCodeTest1) errs = append(errs, ErrorCodeTest1)
errs = append(errs, ErrorCodeTest2.WithDetail( errs = append(errs, ErrorCodeTest2.WithDetail(
map[string]interface{}{"digest": "sometestblobsumdoesntmatter"})) map[string]interface{}{"digest": "sometestblobsumdoesntmatter"}))
errs = append(errs, ErrorCodeTest3.WithArgs("BOOGIE"))
errs = append(errs, ErrorCodeTest3.WithArgs("BOOGIE").WithDetail("data"))
p, err := json.Marshal(errs) p, err := json.Marshal(errs)
@ -89,7 +98,12 @@ func TestErrorsManagement(t *testing.T) {
t.Fatalf("error marashaling errors: %v", err) t.Fatalf("error marashaling errors: %v", err)
} }
expectedJSON := "{\"errors\":[{\"code\":\"TEST1\",\"message\":\"test error 1\"},{\"code\":\"TEST2\",\"message\":\"test error 2\",\"detail\":{\"digest\":\"sometestblobsumdoesntmatter\"}}]}" expectedJSON := `{"errors":[` +
`{"code":"TEST1","message":"test error 1"},` +
`{"code":"TEST2","message":"test error 2","detail":{"digest":"sometestblobsumdoesntmatter"}},` +
`{"code":"TEST3","message":"Sorry \"BOOGIE\" isn't valid"},` +
`{"code":"TEST3","message":"Sorry \"BOOGIE\" isn't valid","detail":"data"}` +
`]}`
if string(p) != expectedJSON { if string(p) != expectedJSON {
t.Fatalf("unexpected json:\ngot:\n%q\n\nexpected:\n%q", string(p), expectedJSON) t.Fatalf("unexpected json:\ngot:\n%q\n\nexpected:\n%q", string(p), expectedJSON)
@ -105,6 +119,13 @@ func TestErrorsManagement(t *testing.T) {
t.Fatalf("errors not equal after round trip:\nunmarshaled:\n%#v\n\nerrs:\n%#v", unmarshaled, errs) t.Fatalf("errors not equal after round trip:\nunmarshaled:\n%#v\n\nerrs:\n%#v", unmarshaled, errs)
} }
// Test the arg substitution stuff
e1 := unmarshaled[3].(Error)
exp1 := `Sorry "BOOGIE" isn't valid`
if e1.Message != exp1 {
t.Fatalf("Wrong msg, got:\n%q\n\nexpected:\n%q", e1.Message, exp1)
}
// Test again with a single value this time // Test again with a single value this time
errs = Errors{ErrorCodeUnknown} errs = Errors{ErrorCodeUnknown}
expectedJSON = "{\"errors\":[{\"code\":\"UNKNOWN\",\"message\":\"unknown error\"}]}" expectedJSON = "{\"errors\":[{\"code\":\"UNKNOWN\",\"message\":\"unknown error\"}]}"
@ -128,4 +149,26 @@ func TestErrorsManagement(t *testing.T) {
t.Fatalf("errors not equal after round trip:\nunmarshaled:\n%#v\n\nerrs:\n%#v", unmarshaled, errs) t.Fatalf("errors not equal after round trip:\nunmarshaled:\n%#v\n\nerrs:\n%#v", unmarshaled, errs)
} }
// Verify that calling WithArgs() more than once does the right thing.
// Meaning creates a new Error and uses the ErrorCode Message
e1 = ErrorCodeTest3.WithArgs("test1")
e2 := e1.WithArgs("test2")
if &e1 == &e2 {
t.Fatalf("args: e2 and e1 should not be the same, but they are")
}
if e2.Message != `Sorry "test2" isn't valid` {
t.Fatalf("e2 had wrong message: %q", e2.Message)
}
// Verify that calling WithDetail() more than once does the right thing.
// Meaning creates a new Error and overwrites the old detail field
e1 = ErrorCodeTest3.WithDetail("stuff1")
e2 = e1.WithDetail("stuff2")
if &e1 == &e2 {
t.Fatalf("detail: e2 and e1 should not be the same, but they are")
}
if e2.Detail != `stuff2` {
t.Fatalf("e2 had wrong detail: %q", e2.Detail)
}
} }

View file

@ -90,7 +90,7 @@ func TestUploadReadFrom(t *testing.T) {
[ [
{ {
"code": "BLOB_UPLOAD_INVALID", "code": "BLOB_UPLOAD_INVALID",
"message": "invalid upload identifier", "message": "blob upload invalid",
"detail": "more detail" "detail": "more detail"
} }
] ]
@ -174,11 +174,11 @@ func TestUploadReadFrom(t *testing.T) {
if v2Err.Code != v2.ErrorCodeBlobUploadInvalid { if v2Err.Code != v2.ErrorCodeBlobUploadInvalid {
t.Fatalf("Unexpected error code: %s, expected %d", v2Err.Code.String(), v2.ErrorCodeBlobUploadInvalid) t.Fatalf("Unexpected error code: %s, expected %d", v2Err.Code.String(), v2.ErrorCodeBlobUploadInvalid)
} }
if expected := "blob upload invalid"; v2Err.Message() != expected { if expected := "blob upload invalid"; v2Err.Message != expected {
t.Fatalf("Unexpected error message: %s, expected %s", v2Err.Message(), expected) t.Fatalf("Unexpected error message: %q, expected %q", v2Err.Message, expected)
} }
if expected := "more detail"; v2Err.Detail.(string) != expected { if expected := "more detail"; v2Err.Detail.(string) != expected {
t.Fatalf("Unexpected error message: %s, expected %s", v2Err.Detail.(string), expected) t.Fatalf("Unexpected error message: %q, expected %q", v2Err.Detail.(string), expected)
} }
} }

View file

@ -52,10 +52,14 @@ func handleErrorResponse(resp *http.Response) error {
if resp.StatusCode == 401 { if resp.StatusCode == 401 {
err := parseHTTPErrorResponse(resp.Body) err := parseHTTPErrorResponse(resp.Body)
if uErr, ok := err.(*UnexpectedHTTPResponseError); ok { if uErr, ok := err.(*UnexpectedHTTPResponseError); ok {
return &errcode.Error{ return v2.ErrorCodeUnauthorized.WithDetail(uErr.Response)
Code: v2.ErrorCodeUnauthorized, /*
Detail: uErr.Response, return &errcode.Error{
} Code: v2.ErrorCodeUnauthorized,
Message: v2.ErrorCodeUnauthorized.Message(),
Detail: uErr.Response,
}
*/
} }
return err return err
} }

View file

@ -669,14 +669,14 @@ func TestManifestUnauthorized(t *testing.T) {
if err == nil { if err == nil {
t.Fatal("Expected error fetching manifest") t.Fatal("Expected error fetching manifest")
} }
v2Err, ok := err.(*errcode.Error) v2Err, ok := err.(errcode.Error)
if !ok { if !ok {
t.Fatalf("Unexpected error type: %#v", err) t.Fatalf("Unexpected error type: %#v", err)
} }
if v2Err.Code != v2.ErrorCodeUnauthorized { if v2Err.Code != v2.ErrorCodeUnauthorized {
t.Fatalf("Unexpected error code: %s", v2Err.Code.String()) t.Fatalf("Unexpected error code: %s", v2Err.Code.String())
} }
if expected := errcode.ErrorCode(v2.ErrorCodeUnauthorized).Message(); v2Err.Message() != expected { if expected := v2.ErrorCodeUnauthorized.Message(); v2Err.Message != expected {
t.Fatalf("Unexpected message value: %s, expected %s", v2Err.Message(), expected) t.Fatalf("Unexpected message value: %q, expected %q", v2Err.Message, expected)
} }
} }