package autorest
// Copyright 2017 Microsoft Corporation
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
import (
"bytes"
"context"
"encoding/json"
"encoding/xml"
"fmt"
"io"
"io/ioutil"
"mime/multipart"
"net/http"
"net/url"
"strings"
)
const (
mimeTypeJSON = "application/json"
mimeTypeOctetStream = "application/octet-stream"
mimeTypeFormPost = "application/x-www-form-urlencoded"
headerAuthorization = "Authorization"
headerAuxAuthorization = "x-ms-authorization-auxiliary"
headerContentType = "Content-Type"
headerUserAgent = "User-Agent"
)
// used as a key type in context.WithValue()
type ctxPrepareDecorators struct{}
// WithPrepareDecorators adds the specified PrepareDecorators to the provided context.
// If no PrepareDecorators are provided the context is unchanged.
func WithPrepareDecorators(ctx context.Context, prepareDecorator []PrepareDecorator) context.Context {
if len(prepareDecorator) == 0 {
return ctx
}
return context.WithValue(ctx, ctxPrepareDecorators{}, prepareDecorator)
}
// GetPrepareDecorators returns the PrepareDecorators in the provided context or the provided default PrepareDecorators.
func GetPrepareDecorators(ctx context.Context, defaultPrepareDecorators ...PrepareDecorator) []PrepareDecorator {
inCtx := ctx.Value(ctxPrepareDecorators{})
if pd, ok := inCtx.([]PrepareDecorator); ok {
return pd
}
return defaultPrepareDecorators
}
// Preparer is the interface that wraps the Prepare method.
//
// Prepare accepts and possibly modifies an http.Request (e.g., adding Headers). Implementations
// must ensure to not share or hold per-invocation state since Preparers may be shared and re-used.
type Preparer interface {
Prepare(*http.Request) (*http.Request, error)
}
// PreparerFunc is a method that implements the Preparer interface.
type PreparerFunc func(*http.Request) (*http.Request, error)
// Prepare implements the Preparer interface on PreparerFunc.
func (pf PreparerFunc) Prepare(r *http.Request) (*http.Request, error) {
return pf(r)
}
// PrepareDecorator takes and possibly decorates, by wrapping, a Preparer. Decorators may affect the
// http.Request and pass it along or, first, pass the http.Request along then affect the result.
type PrepareDecorator func(Preparer) Preparer
// CreatePreparer creates, decorates, and returns a Preparer.
// Without decorators, the returned Preparer returns the passed http.Request unmodified.
// Preparers are safe to share and re-use.
func CreatePreparer(decorators ...PrepareDecorator) Preparer {
return DecoratePreparer(
Preparer(PreparerFunc(func(r *http.Request) (*http.Request, error) { return r, nil })),
decorators...)
}
// DecoratePreparer accepts a Preparer and a, possibly empty, set of PrepareDecorators, which it
// applies to the Preparer. Decorators are applied in the order received, but their affect upon the
// request depends on whether they are a pre-decorator (change the http.Request and then pass it
// along) or a post-decorator (pass the http.Request along and alter it on return).
func DecoratePreparer(p Preparer, decorators ...PrepareDecorator) Preparer {
for _, decorate := range decorators {
p = decorate(p)
}
return p
}
// Prepare accepts an http.Request and a, possibly empty, set of PrepareDecorators.
// It creates a Preparer from the decorators which it then applies to the passed http.Request.
func Prepare(r *http.Request, decorators ...PrepareDecorator) (*http.Request, error) {
if r == nil {
return nil, NewError("autorest", "Prepare", "Invoked without an http.Request")
}
return CreatePreparer(decorators...).Prepare(r)
}
// WithNothing returns a "do nothing" PrepareDecorator that makes no changes to the passed
// http.Request.
func WithNothing() PrepareDecorator {
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
return p.Prepare(r)
})
}
}
// WithHeader returns a PrepareDecorator that sets the specified HTTP header of the http.Request to
// the passed value. It canonicalizes the passed header name (via http.CanonicalHeaderKey) before
// adding the header.
func WithHeader(header string, value string) PrepareDecorator {
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
if r.Header == nil {
r.Header = make(http.Header)
}
r.Header.Set(http.CanonicalHeaderKey(header), value)
}
return r, err
})
}
}
// WithHeaders returns a PrepareDecorator that sets the specified HTTP headers of the http.Request to
// the passed value. It canonicalizes the passed headers name (via http.CanonicalHeaderKey) before
// adding them.
func WithHeaders(headers map[string]interface{}) PrepareDecorator {
h := ensureValueStrings(headers)
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
if r.Header == nil {
r.Header = make(http.Header)
}
for name, value := range h {
r.Header.Set(http.CanonicalHeaderKey(name), value)
}
}
return r, err
})
}
}
// WithBearerAuthorization returns a PrepareDecorator that adds an HTTP Authorization header whose
// value is "Bearer " followed by the supplied token.
func WithBearerAuthorization(token string) PrepareDecorator {
return WithHeader(headerAuthorization, fmt.Sprintf("Bearer %s", token))
}
// AsContentType returns a PrepareDecorator that adds an HTTP Content-Type header whose value
// is the passed contentType.
func AsContentType(contentType string) PrepareDecorator {
return WithHeader(headerContentType, contentType)
}
// WithUserAgent returns a PrepareDecorator that adds an HTTP User-Agent header whose value is the
// passed string.
func WithUserAgent(ua string) PrepareDecorator {
return WithHeader(headerUserAgent, ua)
}
// AsFormURLEncoded returns a PrepareDecorator that adds an HTTP Content-Type header whose value is
// "application/x-www-form-urlencoded".
func AsFormURLEncoded() PrepareDecorator {
return AsContentType(mimeTypeFormPost)
}
// AsJSON returns a PrepareDecorator that adds an HTTP Content-Type header whose value is
// "application/json".
func AsJSON() PrepareDecorator {
return AsContentType(mimeTypeJSON)
}
// AsOctetStream returns a PrepareDecorator that adds the "application/octet-stream" Content-Type header.
func AsOctetStream() PrepareDecorator {
return AsContentType(mimeTypeOctetStream)
}
// WithMethod returns a PrepareDecorator that sets the HTTP method of the passed request. The
// decorator does not validate that the passed method string is a known HTTP method.
func WithMethod(method string) PrepareDecorator {
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r.Method = method
return p.Prepare(r)
})
}
}
// AsDelete returns a PrepareDecorator that sets the HTTP method to DELETE.
func AsDelete() PrepareDecorator { return WithMethod("DELETE") }
// AsGet returns a PrepareDecorator that sets the HTTP method to GET.
func AsGet() PrepareDecorator { return WithMethod("GET") }
// AsHead returns a PrepareDecorator that sets the HTTP method to HEAD.
func AsHead() PrepareDecorator { return WithMethod("HEAD") }
// AsMerge returns a PrepareDecorator that sets the HTTP method to MERGE.
func AsMerge() PrepareDecorator { return WithMethod("MERGE") }
// AsOptions returns a PrepareDecorator that sets the HTTP method to OPTIONS.
func AsOptions() PrepareDecorator { return WithMethod("OPTIONS") }
// AsPatch returns a PrepareDecorator that sets the HTTP method to PATCH.
func AsPatch() PrepareDecorator { return WithMethod("PATCH") }
// AsPost returns a PrepareDecorator that sets the HTTP method to POST.
func AsPost() PrepareDecorator { return WithMethod("POST") }
// AsPut returns a PrepareDecorator that sets the HTTP method to PUT.
func AsPut() PrepareDecorator { return WithMethod("PUT") }
// WithBaseURL returns a PrepareDecorator that populates the http.Request with a url.URL constructed
// from the supplied baseUrl.
func WithBaseURL(baseURL string) PrepareDecorator {
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
var u *url.URL
if u, err = url.Parse(baseURL); err != nil {
return r, err
}
if u.Scheme == "" {
err = fmt.Errorf("autorest: No scheme detected in URL %s", baseURL)
}
if err == nil {
r.URL = u
}
}
return r, err
})
}
}
// WithBytes returns a PrepareDecorator that takes a list of bytes
// which passes the bytes directly to the body
func WithBytes(input *[]byte) PrepareDecorator {
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
if input == nil {
return r, fmt.Errorf("Input Bytes was nil")
}
r.ContentLength = int64(len(*input))
r.Body = ioutil.NopCloser(bytes.NewReader(*input))
}
return r, err
})
}
}
// WithCustomBaseURL returns a PrepareDecorator that replaces brace-enclosed keys within the
// request base URL (i.e., http.Request.URL) with the corresponding values from the passed map.
func WithCustomBaseURL(baseURL string, urlParameters map[string]interface{}) PrepareDecorator {
parameters := ensureValueStrings(urlParameters)
for key, value := range parameters {
baseURL = strings.Replace(baseURL, "{"+key+"}", value, -1)
}
return WithBaseURL(baseURL)
}
// WithFormData returns a PrepareDecoratore that "URL encodes" (e.g., bar=baz&foo=quux) into the
// http.Request body.
func WithFormData(v url.Values) PrepareDecorator {
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
s := v.Encode()
if r.Header == nil {
r.Header = make(http.Header)
}
r.Header.Set(http.CanonicalHeaderKey(headerContentType), mimeTypeFormPost)
r.ContentLength = int64(len(s))
r.Body = ioutil.NopCloser(strings.NewReader(s))
}
return r, err
})
}
}
// WithMultiPartFormData returns a PrepareDecoratore that "URL encodes" (e.g., bar=baz&foo=quux) form parameters
// into the http.Request body.
func WithMultiPartFormData(formDataParameters map[string]interface{}) PrepareDecorator {
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
var body bytes.Buffer
writer := multipart.NewWriter(&body)
for key, value := range formDataParameters {
if rc, ok := value.(io.ReadCloser); ok {
var fd io.Writer
if fd, err = writer.CreateFormFile(key, key); err != nil {
return r, err
}
if _, err = io.Copy(fd, rc); err != nil {
return r, err
}
} else {
if err = writer.WriteField(key, ensureValueString(value)); err != nil {
return r, err
}
}
}
if err = writer.Close(); err != nil {
return r, err
}
if r.Header == nil {
r.Header = make(http.Header)
}
r.Header.Set(http.CanonicalHeaderKey(headerContentType), writer.FormDataContentType())
r.Body = ioutil.NopCloser(bytes.NewReader(body.Bytes()))
r.ContentLength = int64(body.Len())
return r, err
}
return r, err
})
}
}
// WithFile returns a PrepareDecorator that sends file in request body.
func WithFile(f io.ReadCloser) PrepareDecorator {
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
b, err := ioutil.ReadAll(f)
if err != nil {
return r, err
}
r.Body = ioutil.NopCloser(bytes.NewReader(b))
r.ContentLength = int64(len(b))
}
return r, err
})
}
}
// WithBool returns a PrepareDecorator that encodes the passed bool into the body of the request
// and sets the Content-Length header.
func WithBool(v bool) PrepareDecorator {
return WithString(fmt.Sprintf("%v", v))
}
// WithFloat32 returns a PrepareDecorator that encodes the passed float32 into the body of the
// request and sets the Content-Length header.
func WithFloat32(v float32) PrepareDecorator {
return WithString(fmt.Sprintf("%v", v))
}
// WithFloat64 returns a PrepareDecorator that encodes the passed float64 into the body of the
// request and sets the Content-Length header.
func WithFloat64(v float64) PrepareDecorator {
return WithString(fmt.Sprintf("%v", v))
}
// WithInt32 returns a PrepareDecorator that encodes the passed int32 into the body of the request
// and sets the Content-Length header.
func WithInt32(v int32) PrepareDecorator {
return WithString(fmt.Sprintf("%v", v))
}
// WithInt64 returns a PrepareDecorator that encodes the passed int64 into the body of the request
// and sets the Content-Length header.
func WithInt64(v int64) PrepareDecorator {
return WithString(fmt.Sprintf("%v", v))
}
// WithString returns a PrepareDecorator that encodes the passed string into the body of the request
// and sets the Content-Length header.
func WithString(v string) PrepareDecorator {
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
r.ContentLength = int64(len(v))
r.Body = ioutil.NopCloser(strings.NewReader(v))
}
return r, err
})
}
}
// WithJSON returns a PrepareDecorator that encodes the data passed as JSON into the body of the
// request and sets the Content-Length header.
func WithJSON(v interface{}) PrepareDecorator {
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
b, err := json.Marshal(v)
if err == nil {
r.ContentLength = int64(len(b))
r.Body = ioutil.NopCloser(bytes.NewReader(b))
}
}
return r, err
})
}
}
// WithXML returns a PrepareDecorator that encodes the data passed as XML into the body of the
// request and sets the Content-Length header.
func WithXML(v interface{}) PrepareDecorator {
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
b, err := xml.Marshal(v)
if err == nil {
// we have to tack on an XML header
withHeader := xml.Header + string(b)
bytesWithHeader := []byte(withHeader)
r.ContentLength = int64(len(bytesWithHeader))
r.Body = ioutil.NopCloser(bytes.NewReader(bytesWithHeader))
}
}
return r, err
})
}
}
// WithPath returns a PrepareDecorator that adds the supplied path to the request URL. If the path
// is absolute (that is, it begins with a "/"), it replaces the existing path.
func WithPath(path string) PrepareDecorator {
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
if r.URL == nil {
return r, NewError("autorest", "WithPath", "Invoked with a nil URL")
}
if r.URL, err = parseURL(r.URL, path); err != nil {
return r, err
}
}
return r, err
})
}
}
// WithEscapedPathParameters returns a PrepareDecorator that replaces brace-enclosed keys within the
// request path (i.e., http.Request.URL.Path) with the corresponding values from the passed map. The
// values will be escaped (aka URL encoded) before insertion into the path.
func WithEscapedPathParameters(path string, pathParameters map[string]interface{}) PrepareDecorator {
parameters := escapeValueStrings(ensureValueStrings(pathParameters))
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
if r.URL == nil {
return r, NewError("autorest", "WithEscapedPathParameters", "Invoked with a nil URL")
}
for key, value := range parameters {
path = strings.Replace(path, "{"+key+"}", value, -1)
}
if r.URL, err = parseURL(r.URL, path); err != nil {
return r, err
}
}
return r, err
})
}
}
// WithPathParameters returns a PrepareDecorator that replaces brace-enclosed keys within the
// request path (i.e., http.Request.URL.Path) with the corresponding values from the passed map.
func WithPathParameters(path string, pathParameters map[string]interface{}) PrepareDecorator {
parameters := ensureValueStrings(pathParameters)
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
if r.URL == nil {
return r, NewError("autorest", "WithPathParameters", "Invoked with a nil URL")
}
for key, value := range parameters {
path = strings.Replace(path, "{"+key+"}", value, -1)
}
if r.URL, err = parseURL(r.URL, path); err != nil {
return r, err
}
}
return r, err
})
}
}
func parseURL(u *url.URL, path string) (*url.URL, error) {
p := strings.TrimRight(u.String(), "/")
if !strings.HasPrefix(path, "/") {
path = "/" + path
}
return url.Parse(p + path)
}
// WithQueryParameters returns a PrepareDecorators that encodes and applies the query parameters
// given in the supplied map (i.e., key=value).
func WithQueryParameters(queryParameters map[string]interface{}) PrepareDecorator {
parameters := MapToValues(queryParameters)
return func(p Preparer) Preparer {
return PreparerFunc(func(r *http.Request) (*http.Request, error) {
r, err := p.Prepare(r)
if err == nil {
if r.URL == nil {
return r, NewError("autorest", "WithQueryParameters", "Invoked with a nil URL")
}
v := r.URL.Query()
for key, value := range parameters {
for i := range value {
d, err := url.QueryUnescape(value[i])
if err != nil {
return r, err
}
value[i] = d
}
v[key] = value
}
r.URL.RawQuery = v.Encode()
}
return r, err
})
}
}