[Jupyter] Add a response notebook (#1064)

* Add a response generation jupyter notebook

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Make codespell happy

* precommit codespell exclude

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: abhinavsingh

.pre-commit-config.yaml

@@ -125,8 +125,12 @@ repos:
   rev: v2.1.0
   hooks:
   - id: codespell
-    exclude: >-
-      ^.+\.min\.js$
+    exclude: >
+      (?x)^(
+        tutorial/responses.ipynb|
+        tests/http/test_responses\.py|
+        ^.+\.min\.js$
+      )$
 
 - repo: https://github.com/adrienverge/yamllint.git
   rev: v1.26.2

tests/http/test_responses.py

@@ -0,0 +1,113 @@
+# -*- coding: utf-8 -*-
+"""
+    proxy.py
+    ~~~~~~~~
+    ⚡⚡⚡ Fast, Lightweight, Pluggable, TLS interception capable proxy server focused on
+    Network monitoring, controls & Application development, testing, debugging.
+
+    :copyright: (c) 2013-present by Abhinav Singh and contributors.
+    :license: BSD, see LICENSE for more details.
+
+    .. spelling::
+
+       nd
+"""
+import gzip
+
+import unittest
+
+from proxy.http.parser import ChunkParser
+from proxy.http.responses import okResponse
+from proxy.common.constants import CRLF
+
+
+class TestResponses(unittest.TestCase):
+
+    def test_basic(self) -> None:
+        self.assertEqual(
+            okResponse(),
+            b'HTTP/1.1 200 OK\r\nContent-Length: 0\r\n\r\n',
+        )
+        self.assertEqual(
+            okResponse(
+                headers={
+                    b'X-Custom-Header': b'my value',
+                },
+            ),
+            b'HTTP/1.1 200 OK\r\nX-Custom-Header: my value\r\nContent-Length: 0\r\n\r\n',
+        )
+        self.assertEqual(
+            okResponse(
+                content=b'Hello World',
+                headers={
+                    b'X-Custom-Header': b'my value',
+                },
+            ),
+            b'HTTP/1.1 200 OK\r\nX-Custom-Header: my value\r\nContent-Length: 11\r\n\r\nHello World',
+        )
+
+    def test_compression(self) -> None:
+        content = b'H' * 21
+        self.assertEqual(
+            gzip.decompress(
+                okResponse(
+                    content=content,
+                    headers={
+                        b'X-Custom-Header': b'my value',
+                    },
+                ).tobytes().split(CRLF + CRLF, maxsplit=1)[-1],
+            ),
+            content,
+        )
+        self.assertEqual(
+            okResponse(
+                content=content,
+                headers={
+                    b'Host': b'jaxl.com',
+                },
+                min_compression_length=len(content),
+            ),
+            b'HTTP/1.1 200 OK\r\nHost: jaxl.com\r\nContent-Length: 21\r\n\r\nHHHHHHHHHHHHHHHHHHHHH',
+        )
+
+    def test_close_header(self) -> None:
+        self.assertEqual(
+            okResponse(
+                content=b'Hello World',
+                headers={
+                    b'Host': b'jaxl.com',
+                },
+                conn_close=True,
+            ),
+            b'HTTP/1.1 200 OK\r\nHost: jaxl.com\r\nContent-Length: 11\r\nConnection: close\r\n\r\nHello World',
+        )
+
+    def test_chunked_without_compression(self) -> None:
+        chunks = ChunkParser.to_chunks(b'Hello World', chunk_size=5)
+        self.assertEqual(
+            okResponse(
+                content=chunks,
+                headers={
+                    b'Transfer-Encoding': b'chunked',
+                },
+                # Avoid compressing chunks for demo purposes here
+                # Ideally you should omit this flag and send
+                # compressed chunks.
+                min_compression_length=len(chunks),
+            ),
+            b'HTTP/1.1 200 OK\r\nTransfer-Encoding: chunked\r\n\r\n5\r\nHello\r\n5\r\n Worl\r\n1\r\nd\r\n0\r\n\r\n',
+        )
+
+    def test_chunked_with_compression(self) -> None:
+        chunks = ChunkParser.to_chunks(b'Hello World', chunk_size=5)
+        self.assertEqual(
+            gzip.decompress(
+                okResponse(
+                    content=chunks,
+                    headers={
+                        b'Transfer-Encoding': b'chunked',
+                    },
+                ).tobytes().split(CRLF + CRLF, maxsplit=1)[-1],
+            ),
+            chunks,
+        )