chore: move Message/MessageConfig -> message.go

Author: jvatic

message.go

@@ -0,0 +1,248 @@
+package httpsign
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"time"
+)
+
+// MessageDetails aggregates the details of a signed message, for a given signature
+type MessageDetails struct {
+	KeyID   string
+	Alg     string
+	Fields  Fields
+	Created *time.Time
+	Expires *time.Time
+	Nonce   *string
+	Tag     *string
+}
+
+// Message represents a parsed HTTP message ready for signature verification.
+type Message struct {
+	headers  http.Header
+	trailers http.Header
+	body     *io.ReadCloser
+
+	method     string
+	url        *url.URL
+	authority  string
+	scheme     string
+	statusCode *int
+	assocReq   *Message
+}
+
+// NewMessage constructs a new Message from the provided config.
+func NewMessage(config *MessageConfig) (*Message, error) {
+	if config == nil {
+		config = NewMessageConfig()
+	}
+
+	hasRequest := config.method != ""
+	hasResponse := config.statusCode != nil
+
+	if !hasRequest && !hasResponse {
+		return nil, fmt.Errorf("message config must have either method (for request) or status code (for response)")
+	}
+
+	if hasRequest && hasResponse {
+		return nil, fmt.Errorf("message config cannot have both request and response fields set")
+	}
+
+	if hasRequest {
+		if config.headers == nil {
+			return nil, fmt.Errorf("request message must have headers")
+		}
+	}
+
+	if hasResponse {
+		if config.headers == nil {
+			return nil, fmt.Errorf("response message must have headers")
+		}
+	}
+
+	var assocReq *Message
+	if config.assocReq != nil {
+		method := config.assocReq.method
+		u := config.assocReq.url
+		headers := config.assocReq.headers
+		authority := config.assocReq.authority
+		scheme := config.assocReq.scheme
+		if method == "" || u == nil || headers == nil || authority == "" || scheme == "" {
+			return nil, fmt.Errorf("invalid associated request")
+		}
+		assocReq = &Message{
+			method:    method,
+			url:       u,
+			headers:   headers,
+			authority: authority,
+			scheme:    scheme,
+		}
+	}
+
+	return &Message{
+		headers:    config.headers,
+		trailers:   config.trailers,
+		body:       config.body,
+		method:     config.method,
+		url:        config.url,
+		authority:  config.authority,
+		scheme:     config.scheme,
+		statusCode: config.statusCode,
+		assocReq:   assocReq,
+	}, nil
+}
+
+// MessageConfig configures a Message for signature verification.
+type MessageConfig struct {
+	method    string
+	url       *url.URL
+	headers   http.Header
+	trailers  http.Header
+	body      *io.ReadCloser
+	authority string
+	scheme    string
+
+	statusCode *int
+
+	assocReq *MessageConfig
+}
+
+// NewMessageConfig returns a new MessageConfig.
+func NewMessageConfig() *MessageConfig {
+	return &MessageConfig{}
+}
+
+func (b *MessageConfig) WithMethod(method string) *MessageConfig {
+	b.method = method
+	return b
+}
+
+func (b *MessageConfig) WithURL(u *url.URL) *MessageConfig {
+	b.url = u
+	return b
+}
+
+func (b *MessageConfig) WithHeaders(headers http.Header) *MessageConfig {
+	b.headers = headers
+	return b
+}
+
+func (b *MessageConfig) WithTrailers(trailers http.Header) *MessageConfig {
+	b.trailers = trailers
+	return b
+}
+
+func (b *MessageConfig) WithBody(body *io.ReadCloser) *MessageConfig {
+	b.body = body
+	return b
+}
+
+func (b *MessageConfig) WithAuthority(authority string) *MessageConfig {
+	b.authority = authority
+	return b
+}
+
+func (b *MessageConfig) WithScheme(scheme string) *MessageConfig {
+	b.scheme = scheme
+	return b
+}
+
+func (b *MessageConfig) WithStatusCode(statusCode int) *MessageConfig {
+	b.statusCode = &statusCode
+	return b
+}
+
+func (b *MessageConfig) WithAssociatedRequest(method string, u *url.URL, headers http.Header, authority, scheme string) *MessageConfig {
+	b.assocReq = &MessageConfig{
+		method:    method,
+		url:       u,
+		headers:   headers,
+		authority: authority,
+		scheme:    scheme,
+	}
+	return b
+}
+
+func (b *MessageConfig) WithRequest(req *http.Request) *MessageConfig {
+	if req == nil {
+		return b
+	}
+
+	scheme := "http"
+	if req.TLS != nil {
+		scheme = "https"
+	}
+
+	return b.
+		WithMethod(req.Method).
+		WithURL(req.URL).
+		WithHeaders(req.Header).
+		WithTrailers(req.Trailer).
+		WithBody(&req.Body).
+		WithAuthority(req.Host).
+		WithScheme(scheme)
+}
+
+func (b *MessageConfig) WithResponse(res *http.Response, req *http.Request) *MessageConfig {
+	if res == nil {
+		return b
+	}
+
+	b = b.
+		WithStatusCode(res.StatusCode).
+		WithHeaders(res.Header).
+		WithTrailers(res.Trailer).
+		WithBody(&res.Body)
+
+	if req != nil {
+		scheme := "http"
+		if req.TLS != nil {
+			scheme = "https"
+		}
+		b = b.WithAssociatedRequest(req.Method, req.URL, req.Header, req.Host, scheme)
+	}
+
+	return b
+}
+
+// Verify verifies a signature on this message.
+func (m *Message) Verify(signatureName string, verifier Verifier) (*MessageDetails, error) {
+	_, psiSig, err := verifyDebug(signatureName, verifier, m)
+	if err != nil {
+		return nil, err
+	}
+
+	details := &MessageDetails{
+		Fields: psiSig.fields,
+	}
+
+	if keyID, ok := psiSig.params["keyid"].(string); ok {
+		details.KeyID = keyID
+	}
+
+	if alg, ok := psiSig.params["alg"].(string); ok {
+		details.Alg = alg
+	}
+
+	if created, ok := psiSig.params["created"].(int64); ok {
+		t := time.Unix(created, 0)
+		details.Created = &t
+	}
+
+	if expires, ok := psiSig.params["expires"].(int64); ok {
+		t := time.Unix(expires, 0)
+		details.Expires = &t
+	}
+
+	if nonce, ok := psiSig.params["nonce"].(string); ok {
+		details.Nonce = &nonce
+	}
+
+	if tag, ok := psiSig.params["tag"].(string); ok {
+		details.Tag = &tag
+	}
+
+	return details, nil
+}