Initial commit

.gitignore

@@ -0,0 +1,2 @@
+cover.out
+cover.html

error.go

@@ -0,0 +1,194 @@
+package jsrest
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/http"
+)
+
+var (
+	ErrBadRequest                   = NewHTTPError(http.StatusBadRequest)
+	ErrUnauthorized                 = NewHTTPError(http.StatusUnauthorized)
+	ErrPaymentRequired              = NewHTTPError(http.StatusPaymentRequired)
+	ErrForbidden                    = NewHTTPError(http.StatusForbidden)
+	ErrNotFound                     = NewHTTPError(http.StatusNotFound)
+	ErrMethodNotAllowed             = NewHTTPError(http.StatusMethodNotAllowed)
+	ErrNotAcceptable                = NewHTTPError(http.StatusNotAcceptable)
+	ErrProxyAuthRequired            = NewHTTPError(http.StatusProxyAuthRequired)
+	ErrRequestTimeout               = NewHTTPError(http.StatusRequestTimeout)
+	ErrConflict                     = NewHTTPError(http.StatusConflict)
+	ErrGone                         = NewHTTPError(http.StatusGone)
+	ErrLengthRequired               = NewHTTPError(http.StatusLengthRequired)
+	ErrPreconditionFailed           = NewHTTPError(http.StatusPreconditionFailed)
+	ErrRequestEntityTooLarge        = NewHTTPError(http.StatusRequestEntityTooLarge)
+	ErrRequestURITooLong            = NewHTTPError(http.StatusRequestURITooLong)
+	ErrUnsupportedMediaType         = NewHTTPError(http.StatusUnsupportedMediaType)
+	ErrRequestedRangeNotSatisfiable = NewHTTPError(http.StatusRequestedRangeNotSatisfiable)
+	ErrExpectationFailed            = NewHTTPError(http.StatusExpectationFailed)
+	ErrTeapot                       = NewHTTPError(http.StatusTeapot)
+	ErrMisdirectedRequest           = NewHTTPError(http.StatusMisdirectedRequest)
+	ErrUnprocessableEntity          = NewHTTPError(http.StatusUnprocessableEntity)
+	ErrLocked                       = NewHTTPError(http.StatusLocked)
+	ErrFailedDependency             = NewHTTPError(http.StatusFailedDependency)
+	ErrTooEarly                     = NewHTTPError(http.StatusTooEarly)
+	ErrUpgradeRequired              = NewHTTPError(http.StatusUpgradeRequired)
+	ErrPreconditionRequired         = NewHTTPError(http.StatusPreconditionRequired)
+	ErrTooManyRequests              = NewHTTPError(http.StatusTooManyRequests)
+	ErrRequestHeaderFieldsTooLarge  = NewHTTPError(http.StatusRequestHeaderFieldsTooLarge)
+	ErrUnavailableForLegalReasons   = NewHTTPError(http.StatusUnavailableForLegalReasons)
+
+	ErrInternalServerError           = NewHTTPError(http.StatusInternalServerError)
+	ErrNotImplemented                = NewHTTPError(http.StatusNotImplemented)
+	ErrBadGateway                    = NewHTTPError(http.StatusBadGateway)
+	ErrServiceUnavailable            = NewHTTPError(http.StatusServiceUnavailable)
+	ErrGatewayTimeout                = NewHTTPError(http.StatusGatewayTimeout)
+	ErrHTTPVersionNotSupported       = NewHTTPError(http.StatusHTTPVersionNotSupported)
+	ErrVariantAlsoNegotiates         = NewHTTPError(http.StatusVariantAlsoNegotiates)
+	ErrInsufficientStorage           = NewHTTPError(http.StatusInsufficientStorage)
+	ErrLoopDetected                  = NewHTTPError(http.StatusLoopDetected)
+	ErrNotExtended                   = NewHTTPError(http.StatusNotExtended)
+	ErrNetworkAuthenticationRequired = NewHTTPError(http.StatusNetworkAuthenticationRequired)
+)
+
+type HTTPError struct {
+	Code    int
+	Message string
+}
+
+func NewHTTPError(code int) *HTTPError {
+	return &HTTPError{
+		Code:    code,
+		Message: http.StatusText(code),
+	}
+}
+
+func (err *HTTPError) Error() string {
+	return fmt.Sprintf("[%d] %s", err.Code, err.Message)
+}
+
+type SilentJoinError struct {
+	Wraps []error
+}
+
+func SilentJoin(errs ...error) *SilentJoinError {
+	return &SilentJoinError{
+		Wraps: errs,
+	}
+}
+
+func (err *SilentJoinError) Error() string {
+	return err.Wraps[0].Error()
+}
+
+func (err *SilentJoinError) Unwrap() []error {
+	return err.Wraps
+}
+
+func WriteError(w http.ResponseWriter, err error) {
+	je := ToJSONError(err)
+
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(je.Code)
+
+	enc := json.NewEncoder(w)
+	_ = enc.Encode(je) //nolint:errchkjson
+}
+
+func Errorf(he *HTTPError, format string, a ...any) error {
+	err := fmt.Errorf(format, a...) //nolint:goerr113
+
+	if hasHTTPError(err) {
+		return err
+	}
+
+	return SilentJoin(err, he)
+}
+
+type JSONError struct {
+	Code     int      `json:"-"`
+	Messages []string `json:"messages"`
+}
+
+func (je *JSONError) Error() string {
+	if len(je.Messages) > 0 {
+		return je.Messages[0]
+	}
+
+	return "no error message"
+}
+
+func (je *JSONError) Unwrap() error {
+	if len(je.Messages) > 1 {
+		return &JSONError{
+			Code:     je.Code,
+			Messages: je.Messages[1:],
+		}
+	}
+
+	return nil
+}
+
+func ToJSONError(err error) *JSONError {
+	je := &JSONError{
+		Code: 500,
+	}
+	je.importError(err)
+
+	return je
+}
+
+func ReadError(in []byte) error {
+	jse := &JSONError{}
+
+	err := json.Unmarshal(in, jse)
+	if err == nil {
+		return jse
+	}
+
+	return errors.New(string(in)) //nolint:goerr113
+}
+
+type singleUnwrap interface {
+	Unwrap() error
+}
+
+type multiUnwrap interface {
+	Unwrap() []error
+}
+
+func hasHTTPError(err error) bool {
+	if _, has := err.(*HTTPError); has { //nolint:errorlint
+		return true
+	}
+
+	if unwrap, ok := err.(singleUnwrap); ok { //nolint:errorlint
+		return hasHTTPError(unwrap.Unwrap())
+	} else if unwrap, ok := err.(multiUnwrap); ok { //nolint:errorlint
+		for _, sub := range unwrap.Unwrap() {
+			if hasHTTPError(sub) {
+				return true
+			}
+		}
+	}
+
+	return false
+}
+
+func (je *JSONError) importError(err error) {
+	if he, ok := err.(*HTTPError); ok { //nolint:errorlint
+		je.Code = he.Code
+	}
+
+	if _, is := err.(*SilentJoinError); !is { //nolint:errorlint
+		je.Messages = append(je.Messages, err.Error())
+	}
+
+	if unwrap, ok := err.(singleUnwrap); ok { //nolint:errorlint
+		je.importError(unwrap.Unwrap())
+	} else if unwrap, ok := err.(multiUnwrap); ok { //nolint:errorlint
+		for _, sub := range unwrap.Unwrap() {
+			je.importError(sub)
+		}
+	}
+}

error_test.go

@@ -0,0 +1,47 @@
+package jsrest_test
+
+import (
+	"errors"
+	"net/http"
+	"testing"
+
+	"github.com/gopatchy/jsrest"
+	"github.com/stretchr/testify/require"
+)
+
+func TestFromError(t *testing.T) {
+	t.Parallel()
+
+	e1 := errors.New("error 1") //nolint:goerr113
+	e2 := jsrest.Errorf(jsrest.ErrBadGateway, "error 2: %w", e1)
+
+	require.ErrorIs(t, e2, e1)
+	require.ErrorIs(t, e2, jsrest.ErrBadGateway)
+
+	je := jsrest.ToJSONError(e2)
+
+	require.Equal(t, http.StatusBadGateway, je.Code)
+	require.Contains(t, je.Messages, "error 1")
+	require.Contains(t, je.Messages, "error 2: error 1")
+	require.Contains(t, je.Messages, "[502] Bad Gateway")
+}
+
+func TestFromErrors(t *testing.T) {
+	t.Parallel()
+
+	e1 := jsrest.Errorf(jsrest.ErrForbidden, "error 1")
+	e2 := errors.New("error 2") //nolint:goerr113
+	e3 := jsrest.Errorf(jsrest.ErrBadGateway, "error 3: %w + %w", e1, e2)
+
+	require.ErrorIs(t, e3, e1)
+	require.ErrorIs(t, e3, e2)
+	require.ErrorIs(t, e3, jsrest.ErrForbidden)
+
+	je := jsrest.ToJSONError(e3)
+
+	require.Equal(t, http.StatusForbidden, je.Code)
+	require.Contains(t, je.Messages, "error 1")
+	require.Contains(t, je.Messages, "error 2")
+	require.Contains(t, je.Messages, "error 3: error 1 + error 2")
+	require.Contains(t, je.Messages, "[403] Forbidden")
+}

go.mod

@@ -0,0 +1,17 @@
+module github.com/gopatchy/jsrest
+
+go 1.19
+
+require (
+	github.com/gopatchy/metadata v0.0.0-20230420053349-25837551c11d
+	github.com/stretchr/testify v1.8.2
+	github.com/vfaronov/httpheader v0.1.0
+	go.uber.org/goleak v1.2.1
+)
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/kr/text v0.2.0 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

go.sum

@@ -0,0 +1,28 @@
+github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/gopatchy/metadata v0.0.0-20230420053349-25837551c11d h1:chunoM47vkWSanIvLx4uRSkLMG6chDZOy09L2tt/bv8=
+github.com/gopatchy/metadata v0.0.0-20230420053349-25837551c11d/go.mod h1:VgD33raUShjDePCDBo55aj+eSXFtUEpMzs+Ie39g2zo=
+github.com/kr/pretty v0.3.0 h1:WgNl7dwNpEZ6jJ9k1snq4pZsg7DOEN8hP9Xw0Tsjwk0=
+github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
+github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/rogpeppe/go-internal v1.8.1-0.20211023094830-115ce09fd6b4 h1:Ha8xCaq6ln1a+R91Km45Oq6lPXj2Mla6CRJYcuV2h1w=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
+github.com/stretchr/testify v1.8.2 h1:+h33VjcLVPDHtOdpUCuF+7gSuG3yGIftsP1YvFihtJ8=
+github.com/stretchr/testify v1.8.2/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
+github.com/vfaronov/httpheader v0.1.0 h1:VdzetvOKRoQVHjSrXcIOwCV6JG5BCAW9rjbVbFPBmb0=
+github.com/vfaronov/httpheader v0.1.0/go.mod h1:ZBxgbYu6nbN5V9Ptd1yYUUan0voD0O8nZLXHyxLgoLE=
+go.uber.org/goleak v1.2.1 h1:NBol2c7O1ZokfZ0LEU9K6Whx/KnwvepVetCUhtKja4A=
+go.uber.org/goleak v1.2.1/go.mod h1:qlT2yGI9QafXHhZZLxlSuNsMw3FFLxBr+tBRlmO1xH4=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

json.go

@@ -0,0 +1,66 @@
+package jsrest
+
+import (
+	"encoding/json"
+	"errors"
+	"net/http"
+
+	"github.com/gopatchy/metadata"
+	"github.com/vfaronov/httpheader"
+)
+
+var ErrUnsupportedContentType = errors.New("unsupported Content-Type")
+
+func Read(r *http.Request, obj any) error {
+	contentType, _ := httpheader.ContentType(r.Header)
+
+	switch contentType {
+	case "":
+		fallthrough
+	case "application/json":
+		break
+
+	default:
+		return Errorf(ErrUnsupportedMediaType, "Content-Type: %s", contentType)
+	}
+
+	dec := json.NewDecoder(r.Body)
+	dec.DisallowUnknownFields()
+
+	err := dec.Decode(obj)
+	if err != nil {
+		return Errorf(ErrBadRequest, "decode JSON request body failed (%w)", err)
+	}
+
+	return nil
+}
+
+func Write(w http.ResponseWriter, obj any) error {
+	m := metadata.GetMetadata(obj)
+
+	w.Header().Set("Content-Type", "application/json")
+	httpheader.SetETag(w.Header(), httpheader.EntityTag{Opaque: m.ETag})
+
+	enc := json.NewEncoder(w)
+
+	err := enc.Encode(obj)
+	if err != nil {
+		return Errorf(ErrInternalServerError, "encode JSON response failed (%w)", err)
+	}
+
+	return nil
+}
+
+func WriteList(w http.ResponseWriter, list []any, etag string) error {
+	w.Header().Set("Content-Type", "application/json")
+	httpheader.SetETag(w.Header(), httpheader.EntityTag{Opaque: etag})
+
+	enc := json.NewEncoder(w)
+
+	err := enc.Encode(list)
+	if err != nil {
+		return Errorf(ErrInternalServerError, "encode JSON response failed (%w)", err)
+	}
+
+	return nil
+}

json_test.go

@@ -0,0 +1,48 @@
+package jsrest_test
+
+import (
+	"bytes"
+	"net/http"
+	"testing"
+
+	"github.com/gopatchy/jsrest"
+	"github.com/stretchr/testify/require"
+)
+
+type testType struct {
+	Text1 string
+}
+
+func TestRead(t *testing.T) {
+	t.Parallel()
+
+	body := bytes.NewBufferString(`{"text1":"foo"}`)
+
+	req, err := http.NewRequest(http.MethodGet, "xyz", body)
+	require.NoError(t, err)
+
+	req.Header.Set("Content-Type", "application/json")
+
+	obj := &testType{}
+
+	err = jsrest.Read(req, obj)
+	require.NoError(t, err)
+	require.Equal(t, "foo", obj.Text1)
+}
+
+func TestReadContentTypeParams(t *testing.T) {
+	t.Parallel()
+
+	body := bytes.NewBufferString(`{"text1":"bar"}`)
+
+	req, err := http.NewRequest(http.MethodGet, "xyz", body) //nolint:noctx
+	require.NoError(t, err)
+
+	req.Header.Set("Content-Type", "application/json; charset=utf-8")
+
+	obj := &testType{}
+
+	err = jsrest.Read(req, obj)
+	require.NoError(t, err)
+	require.Equal(t, "bar", obj.Text1)
+}

justfile

@@ -0,0 +1,18 @@
+go := env_var_or_default('GOCMD', 'go')
+
+default: tidy test
+
+tidy:
+	{{go}} mod tidy
+	goimports -l -w .
+	gofumpt -l -w .
+	{{go}} fmt ./...
+
+test:
+	{{go}} vet ./...
+	golangci-lint run ./...
+	{{go}} test -race -coverprofile=cover.out -timeout=60s -parallel=10 ./...
+	{{go}} tool cover -html=cover.out -o=cover.html
+
+todo:
+	-git grep -e TODO --and --not -e ignoretodo

pkg_test.go

@@ -0,0 +1,11 @@
+package jsrest_test
+
+import (
+	"testing"
+
+	"go.uber.org/goleak"
+)
+
+func TestMain(m *testing.M) {
+	goleak.VerifyTestMain(m)
+}