Some more fixes and progress getting tests further in 9

Author: hjwp

chapter_09_docker.asciidoc

@@ -579,10 +579,13 @@ An image is essentially a pre-prepared root filesystem,
 including the operating system, dependencies, and any code you want to run.
 
 Once you have an image, you can run one or many containers that use the same image.
+It's a bit like saying, once you've installed your operating system and software,
+you can start up your computer and run that software any number of times,
+without needing to change anything else.
+
+Another way of thinking about it is, images are like classes,
+and containers are like instances.
 
-// DAVID: Not sure whether this is going to be understandable in its current form.
-// An analogy that I find helpful here is that images are like classes
-// and containers are like instances.
 
 ==== A First Cut of a Dockerfile
 
@@ -599,13 +602,7 @@ What do we need to do?  Something like this, right?
 We create a new file called _Dockerfile_ in the base folder of our repo,
 next to the `src/` directory we made earlier:
 
-// DAVID: As discussed, I misread this and put the Dockerfile in src.
-// That led to a difficult to understand error message when I tried to build.
-// ERROR: failed to solve: failed to compute cache key: failed to calculate
-// checksum of ref e126cbb4-3e0c-4e6e-867f-dbfbf5fb190f::k2oys44pcnbefrlpps3ooux7w: "/src": not found
-
 // JAN: I'd suggest to use python3.11:slim or python3:12 slim. Keeping image tags too open leads to issues in a couple of months (not always, but waaay too often)
-// JAN: I'd use Docker comments with # for <1>, <2>, ... Otherwise, you need to edit the code when you paste it
 
 
 
@@ -708,12 +705,14 @@ $ pass:quotes[*docker build -t superlists .*]
 
 Now we can see our image in the list of docker images on the system:
 
+// TODO, this listing was hard to test due to column widths but there must be a way
+[role="skipme"]
 [subs="specialcharacters,quotes"]
 ----
 $ *docker images*
 REPOSITORY   TAG       IMAGE ID       CREATED          SIZE
-[...]
 superlists   latest    522824a399de   2 minutes ago    164MB
+[...]
 ----
 
 
@@ -754,18 +753,18 @@ environment?
 ----
 
 
-// DAVID: I got:
-// python: can't open file '/src/manage.py': [Errno 2] No such file or directory
-
 Ah, we forgot that we need to install Django.
 
 
-=== Installing Django into our Virtualenv
+=== Installing Django in a Virtualenv in our Container Image
 
 Just like on our own machine,
 a virtualenv is useful in a deployed environment to make
-sure we have full control over the packages installed for a particular
-project.
+sure we have full control over the packages installed
+for a particular project.footnote:[
+Even a completely fresh Linux install might have odd things installed
+in its system site packages.
+A virtualenv is a guaranteed clean slate.]
 
 We can create a virtualenv in our Dockerfile
 just like we did on our own machine with `python -m venv`,
@@ -802,7 +801,6 @@ CMD python manage.py runserver
 <3> We install Django with `pip install`, just like we do locally.
 
 
-// DAVID: Why bother with a virtualenv?
 
 ==== Successful Run
 
@@ -983,9 +981,9 @@ Try it on your own computer first:
 ----
 $ pass:quotes[*curl -iv localhost:8888*]
 *   Trying 127.0.0.1:8888...
-* connect to 127.0.0.1 port 8888 failed: Connection refused
+* connect to 127.0.0.1 port 8888 [...]
 *   Trying [::1]:8888...
-* connect to ::1 port 8888 failed: Connection refused
+* connect to ::1 port 8888 [...]
 * Failed to connect to localhost port 8888 after 0 ms: Couldn't connect to
 server
 * Closing connection
@@ -1046,10 +1044,10 @@ The following additional packages will be installed:
 [...]
 root@5ed84681fdf8:/src# pass:quotes[*curl -iv http://localhost:8888*]
 *   Trying 127.0.0.1:8888...
-* Connected to localhost (127.0.0.1) port 8888 (#0)
+* Connected to localhost (127.0.0.1) port 8888
 > GET / HTTP/1.1
 > Host: localhost:8888
-> User-Agent: curl/7.88.1
+> User-Agent: curl/8[...]
 > Accept: */*
 >
 < HTTP/1.1 200 OK
@@ -1120,27 +1118,30 @@ Similarly, if you try our `curl -iv` (outside the container) once again,
 you'll see the error has changed from "Failed to connect",
 to "Empty reply":
 
-[role="ignore-errors"]
+[role="ignore-errors pause-first"]
 [subs="specialcharacters,macros"]
 ----
 $ pass:quotes[*curl -iv localhost:8888*]
 *   Trying 127.0.0.1:8888...
 * Connected to localhost (127.0.0.1) port 8888
 > GET / HTTP/1.1
 > Host: localhost:8888
-> User-Agent: curl/7.88.1
+> User-Agent: curl/8.[...]
 > Accept: */*
 [...]
 * Empty reply from server
-* Closing connection 0
+* Closing connection
 curl: (52) Empty reply from server
 ----
 
+////
+
 NOTE: Depending on your system, instead of `(52) Empty reply from server`,
   You might see `(56) Recv failure: Connection reset by peer`.
   They mean the same thing.
 
-//TODO: double-check what the difference means here.
+TODO: double-check what the difference means here.
+////
 
 
 ==== Essential Googling the Error Message
@@ -1188,6 +1189,9 @@ using the magic "wilcard" IP address `0.0.0.0`:
 // DAVID: Some readers might not be that comfortable with the idea of ports.
 // I think this could do with more explanation.
 
+
+
+[role="sourcecode"]
 .Dockerfile (ch09l007)
 ====
 [source,dockerfile]
@@ -1212,17 +1216,17 @@ Starting development server at http://0.0.0.0:8888/
 
 We can verify it's working with `curl`:
 
+[role="pause-first"]
 [subs="specialcharacters,macros"]
 ----
 $ pass:quotes[*curl -iv localhost:8888*]
 *   Trying 127.0.0.1:8888...
-* Connected to localhost (127.0.0.1) port 8888 (#0)
+* Connected to localhost (127.0.0.1) port 8888
 [...]
 
   </body>
 
 </html>
-* Connection #0 to host localhost left intact
 ----
 
 Looking good!

tests/book_parser.py

@@ -24,6 +24,7 @@ def __init__(self, filename, contents):
         self.skip = False
         self.currentcontents = False
         self.against_server = False
+        self.pause_first = False
 
     def is_diff(self):
         lines = self.contents.split("\n")
@@ -56,6 +57,7 @@ def __init__(self, a_string):
         self.ignore_errors = False
         self.server_command = False
         self.against_server = False
+        self.pause_first = False
         self.dofirst = None
         str.__init__(a_string)
 
@@ -93,6 +95,7 @@ def __init__(self, a_string):
         self.dofirst = None
         self.jasmine_output = False
         self.against_server = False
+        self.pause_first = False
         str.__init__(a_string)
 
     @property
@@ -216,6 +219,10 @@ def parse_listing(listing):  # noqa: PLR0912
         for listing in outputs:
             listing.against_server = True
 
+    if "pause-first" in classes:
+        for listing in outputs:
+            listing.pause_first = True
+
     return outputs
 
 

tests/book_tester.py

@@ -732,6 +732,9 @@ def run_interactive_manage_py(self, listing):
 
     def recognise_listing_and_process_it(self):
         listing = self.listings[self.pos]
+        if listing.pause_first:
+            print('pausing first')
+            time.sleep(2)
         if listing.dofirst:
             print("DOFIRST", listing.dofirst)
             self.sourcetree.patch_from_commit(
@@ -805,7 +808,7 @@ def recognise_listing_and_process_it(self):
 
         elif listing.type == "docker run tty":
             self.sourcetree.run_command(
-                "docker kill $(docker ps -q)", ignore_errors=True
+                "docker kill $(docker ps -q)", ignore_errors=True, silent=True
             )
             fixed = Command(listing.replace(" -it ", " -t "))
             next_listing = self.listings[self.pos + 1]

tests/test_book_tester.py

@@ -600,7 +600,8 @@ def test_only_ignores_exactly_32_char_strings_no_whitespace(self):
 
     def test_ignores_docker_image_ids_and_creation_time(self):
         actual = "superlists   latest    522824a399de   2 weeks ago     164MB"
-        expected = Output("superlists   latest    522824a399de   2 minutes ago   164MB")
+        expected = Output("superlists   latest    622824a399de   2 minutes ago   164MB")
+        actual = "superlists                            latest    4856d33cf356   55 minutes ago   167MB"
         self.assert_console_output_correct(actual, expected)
         self.assertTrue(expected.was_checked)
         with self.assertRaises(AssertionError):

tests/test_chapter_09_docker.py

@@ -1,8 +1,9 @@
 #!/usr/bin/env python3
-import unittest
+import os
 import subprocess
+import unittest
 
-from book_tester import ChapterTest, DO_SERVER_COMMANDS
+from book_tester import DO_SERVER_COMMANDS, ChapterTest
 
 
 class Chapter9Test(ChapterTest):
@@ -28,8 +29,7 @@ def test_listings_and_commands_and_output(self):
         vm_restore = None  # 'MANUAL_1'
 
         # hack fast-forward
-        skip = True
-        if skip:
+        if os.environ.get("SKIP"):
             self.pos = 8
             # self.pos = 18
             self.sourcetree.run_command(
@@ -46,12 +46,6 @@ def test_listings_and_commands_and_output(self):
                 subprocess.check_call(["vagrant", "up"])
 
         while self.pos < len(self.listings):
-            if self.pos == 47:
-                assert "curl -iv" in self.listings[self.pos]
-                print('sleeping')
-                # breakpoint()
-                import time; time.sleep(1)
-
             listing = self.listings[self.pos]
             print(self.pos, listing.type, repr(listing))
             self.recognise_listing_and_process_it()