Revert to buffered response

The http handler closes the requests body after the first response flush. Ideally it won't close the request body and after each request body line read we will write a response in a streaming fashion, thus not consuming tons of RAM. This will result in "Transfer-Encoding: chunked" instead of buffering the response and sending "Content-Length: XXX".

Author: assafmo

main.go

@@ -75,6 +75,7 @@ func main() {
 
 func query(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Server", "SQLiteQueryServer v"+version)
+	// w.Header().Set("X-Content-Type-Options", "nosniff") // prevent browsers from doing MIME-type sniffing
 
 	if r.URL.Path != "/query" {
 		http.Error(w, helpMessage, http.StatusNotFound)
@@ -85,18 +86,18 @@ func query(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	wFlusher, ok := w.(http.Flusher)
-	if !ok {
-		http.Error(w,
-			fmt.Sprintf("Error creating a stream writer.\n\n%s", helpMessage), http.StatusInternalServerError)
-		return
-	}
+	// wFlusher, ok := w.(http.Flusher)
+	// if !ok {
+	// 	http.Error(w,
+	// 		fmt.Sprintf("Error creating a stream writer.\n\n%s", helpMessage), http.StatusInternalServerError)
+	// 	return
+	// }
 
 	w.Header().Set("Content-Type", "application/json")
 	outpoutEncoder := json.NewEncoder(w)
 	// start printing the outer array
 	fmt.Fprintf(w, "[")
-	wFlusher.Flush()
+	// wFlusher.Flush()
 
 	reqCsvReader := csv.NewReader(r.Body)
 	reqCsvReader.ReuseRecord = true
@@ -116,7 +117,7 @@ func query(w http.ResponseWriter, r *http.Request) {
 		if !isFirstQuery {
 			// print comma between queries results
 			fmt.Fprintf(w, ",")
-			wFlusher.Flush()
+			// wFlusher.Flush()
 		}
 		isFirstQuery = false
 
@@ -147,14 +148,14 @@ func query(w http.ResponseWriter, r *http.Request) {
 		fmt.Fprintf(w, `"headers":`)
 		outpoutEncoder.Encode(cols)
 		fmt.Fprintf(w, `,"out":[`) // start printing the out rows array
-		wFlusher.Flush()
+		// wFlusher.Flush()
 
 		isFirstRow := true
 		for rows.Next() {
 			if !isFirstRow {
 				// print comma between rows
 				fmt.Fprintf(w, ",")
-				wFlusher.Flush()
+				// wFlusher.Flush()
 			}
 			isFirstRow = false
 
@@ -184,33 +185,12 @@ func query(w http.ResponseWriter, r *http.Request) {
 
 		// finish printing a query result
 		fmt.Fprintf(w, "]}")
-		wFlusher.Flush()
+		// wFlusher.Flush()
 	}
 
 	// finish printing the outer array
 	fmt.Fprintf(w, "]\n")
-	wFlusher.Flush()
-}
-
-func countParams() int {
-	rows, err := queryStmt.Query()
-	if err != nil {
-		regex := regexp.MustCompile(`sql: expected (\d+) arguments, got 0`)
-		regexSubmatches := regex.FindAllStringSubmatch(err.Error(), 1)
-		if len(regexSubmatches) != 1 || len(regexSubmatches[0]) != 2 {
-			// this is weird, return best guess
-			return strings.Count(queryString, "?")
-		}
-		count, err := strconv.Atoi(regexSubmatches[0][1])
-		if err != nil {
-			// this is weirder because the regex is \d+
-			// return best guess
-			return strings.Count(queryString, "?")
-		}
-		return count
-	}
-	rows.Close()
-	return 0
+	// wFlusher.Flush()
 }
 
 func buildHelpMessage() {
@@ -273,3 +253,24 @@ func buildHelpMessage() {
 	- Element #1 is the result of query #1, Element #2 is the result of query #2, and so forth.
 `, serverPort)
 }
+
+func countParams() int {
+	rows, err := queryStmt.Query()
+	if err != nil {
+		regex := regexp.MustCompile(`sql: expected (\d+) arguments, got 0`)
+		regexSubmatches := regex.FindAllStringSubmatch(err.Error(), 1)
+		if len(regexSubmatches) != 1 || len(regexSubmatches[0]) != 2 {
+			// this is weird, return best guess
+			return strings.Count(queryString, "?")
+		}
+		count, err := strconv.Atoi(regexSubmatches[0][1])
+		if err != nil {
+			// this is weirder because the regex is \d+
+			// return best guess
+			return strings.Count(queryString, "?")
+		}
+		return count
+	}
+	rows.Close()
+	return 0
+}