Improving docs

examples/middleware/echo_modifier.rb

@@ -0,0 +1,16 @@
+#!/usr/bin/env ruby
+# encoding: utf-8
+while data = STDIN.gets
+    next unless data
+    data = data.chomp
+
+    decoded = [data].pack("H*")
+    encoded = decoded.unpack("H*").first
+
+    STDOUT.puts encoded
+
+
+    STDERR.puts "[DEBUG][MIDDLEWARE] Original data: #{data}"
+    STDERR.puts "[DEBUG][MIDDLEWARE] Decoded request: #{decoded}"
+    STDERR.puts "[DEBUG][MIDDLEWARE] Encoded data: #{encoded}"
+end

examples/middleware/echo_modifier.sh

@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+#
+# `xxd` utility included into vim-common package
+# It allow hex decoding/encoding
+
+function log {
+    # Logging to stderr, because stdout/stdin used for data transfer
+    >&2 echo "[DEBUG][ECHO] $1"
+}
+
+while read line; do
+    decoded=$(echo -e "$line" | xxd -r -p)
+
+    header=$(echo -e "$decoded" | head -n +1)
+    payload=$(echo -e "$decoded" | tail -n +2)
+
+    encoded=$(echo -e "$header\n$payload" | xxd -p | tr -d "\\n")
+
+    log ""
+    log "==================================="
+
+    case ${header:0:1} in
+    "1")
+        log "Request type: Request"
+        echo "$encoded"
+        ;;
+    "2")
+        log "Request type: Original Response"
+        ;;
+    "3")
+        log "Request type: Replayed Response"
+        ;;
+    *)
+        log "Unknown request type $header"
+    esac
+    log "==================================="
+
+    log "Original data: $line"
+    log "Decoded request: $decoded"
+    log "Encoded data: $encoded"
+done;

examples/middleware/token_modifier.go

@@ -0,0 +1,97 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"encoding/hex"
+	"fmt"
+	"github.com/buger/gor/proto"
+	"os"
+)
+
+// requestID -> originalToken
+var originalTokens map[string][]byte
+
+// originalToken -> replayedToken
+var tokenAliases map[string][]byte
+
+func main() {
+	originalTokens = make(map[string][]byte)
+	tokenAliases = make(map[string][]byte)
+
+	scanner := bufio.NewScanner(os.Stdin)
+
+	for scanner.Scan() {
+		encoded := scanner.Bytes()
+		buf := make([]byte, len(encoded)/2)
+		hex.Decode(buf, encoded)
+
+		go process(buf)
+	}
+}
+
+func process(buf []byte) {
+	// First byte indicate payload type, possible values:
+	//  1 - Request
+	//  2 - Response
+	//  3 - ReplayedResponse
+	payloadType := buf[0]
+	headerSize := 42
+	header := buf[:headerSize]
+	// For each request you should receive 3 payloads (request, response, replayed response) with same request id
+	reqID := string(header[2:headerSize])
+	payload := buf[headerSize:]
+
+	Debug("Received payload:", string(buf))
+
+	switch payloadType {
+	case '1': // Request
+		if bytes.Equal(proto.Path(payload), []byte("/token")) {
+			originalTokens[reqID] = []byte{}
+			Debug("Found token request:", reqID)
+		} else {
+			tokenVal, vs, _ := proto.PathParam(payload, []byte("token"))
+
+			if vs != -1 { // If there is GET token param
+				if alias, ok := tokenAliases[string(tokenVal)]; ok {
+					// Rewrite original token to alias
+					payload = proto.SetPathParam(payload, []byte("token"), alias)
+
+					// Copy modified payload to our buffer
+					copy(buf[headerSize:], payload)
+				}
+			}
+		}
+
+		// Re-compute length in case if payload was modified
+		bufLen := len(header) + len(payload)
+		// Encoding request and sending it back
+		dst := make([]byte, bufLen*2+1)
+		hex.Encode(dst, buf[:bufLen])
+		dst[len(dst)-1] = '\n'
+
+		os.Stdout.Write(dst)
+
+		return
+	case '2': // Original response
+		if _, ok := originalTokens[reqID]; ok {
+			// Token is inside response body
+			secureToken := proto.Body(payload)
+			originalTokens[reqID] = secureToken
+			Debug("Remember origial token:", string(secureToken))
+		}
+	case '3': // Replayed response
+		if originalToken, ok := originalTokens[reqID]; ok {
+			delete(originalTokens, reqID)
+			secureToken := proto.Body(payload)
+			tokenAliases[string(originalToken)] = secureToken
+
+			Debug("Create alias for new token token, was:", string(originalToken), "now:", string(secureToken))
+		}
+	}
+}
+
+func Debug(args ...interface{}) {
+	fmt.Fprint(os.Stderr, "[DEBUG][TOKEN-MOD] ")
+	fmt.Fprintln(os.Stderr, args...)
+}