Age HTTP header

Author: walterwanderley

cmd/sqlite-http-proxy/request.go

@@ -38,7 +38,7 @@ func (h *requestHandler) Handle(r *http.Request, ctx *goproxy.ProxyCtx) (*http.R
 		return r, nil
 	}
 
-	if !readOnly && uint(time.Since(resp.Timestamp).Seconds()) > ttl {
+	if !readOnly && ttl > 0 && uint(time.Since(resp.Timestamp).Seconds()) > ttl {
 		// data is too old, tell the responseHandler to save the new data
 		ctx.UserData = fmt.Sprintf("%s:%d", resp.TableName, resp.DatabaseID)
 		return r, nil
@@ -47,9 +47,17 @@ func (h *requestHandler) Handle(r *http.Request, ctx *goproxy.ProxyCtx) (*http.R
 		slog.Info("serving from database", "url", url, "status", resp.Status, "timestamp", resp.Timestamp.Format(time.RFC3339))
 	}
 
+	header := http.Header(resp.Header)
+	if date := header.Get("Date"); date != "" {
+		d, err := time.Parse(time.RFC1123, date)
+		if err == nil {
+			header.Set("Age", fmt.Sprint(int(time.Since(d).Seconds())))
+		}
+	}
+
 	return r, &http.Response{
 		StatusCode: resp.Status,
 		Body:       resp.Body,
-		Header:     http.Header(resp.Headers),
+		Header:     header,
 	}
 }

db/reository.go

@@ -22,7 +22,7 @@ type Repository interface {
 type Response struct {
 	Status     int
 	Body       io.ReadCloser
-	Headers    map[string][]string
+	Header     map[string][]string
 	Timestamp  time.Time
 	DatabaseID int
 	TableName  string
@@ -78,9 +78,9 @@ func HttpToResponse(resp *http.Response) (*Response, error) {
 	resp.Body = io.NopCloser(bytes.NewReader(bodyBytes))
 
 	return &Response{
-		Status:  resp.StatusCode,
-		Headers: resp.Header,
-		Body:    io.NopCloser(bytes.NewReader(bodyBytes)),
+		Status: resp.StatusCode,
+		Header: resp.Header,
+		Body:   io.NopCloser(bytes.NewReader(bodyBytes)),
 	}, nil
 }
 
@@ -108,7 +108,7 @@ func rowToResponse(row *sql.Row) (*Response, error) {
 	return &Response{
 		Status:    status,
 		Body:      io.NopCloser(strings.NewReader(body)),
-		Headers:   headersMap,
+		Header:    headersMap,
 		Timestamp: timestamp,
 	}, nil
 }
@@ -131,7 +131,7 @@ func execWriter(ctx context.Context, stmt *sql.Stmt, url string, resp *Response)
 	bodyStr := string(body)
 
 	var headersBuf bytes.Buffer
-	json.NewEncoder(&headersBuf).Encode(resp.Headers)
+	json.NewEncoder(&headersBuf).Encode(resp.Header)
 	headers := headersBuf.String()
 
 	_, err = stmt.ExecContext(ctx,

http/ro_transport.go

@@ -51,7 +51,7 @@ func (t *readOnlyTransport) RoundTrip(req *http.Request) (*http.Response, error)
 	return &http.Response{
 		StatusCode: resp.Status,
 		Body:       resp.Body,
-		Header:     http.Header(resp.Headers),
+		Header:     http.Header(resp.Header),
 	}, nil
 
 }

http/rw_transport.go

@@ -58,7 +58,7 @@ func (t *readWriteTransport) RoundTrip(req *http.Request) (*http.Response, error
 	return &http.Response{
 		StatusCode: respDB.Status,
 		Body:       respDB.Body,
-		Header:     http.Header(respDB.Headers),
+		Header:     http.Header(respDB.Header),
 	}, nil
 
 }