CUCC Expedition Handbook

Troggle - software development laptop

Software development machine

For troggle itself, you need a linux machine. We all use Debian or Debian-derived machines (Debian itself, Ubuntu, Xubuntu etc.) but other forms of linux may work. Running Debian or Ubuntu under WSL on Windows 10 works fine.

If you want to work on the troggle source code and be able to commit to the server git repo, your account will need to be added to the troggle project members list. Contact wookey at wookware dot org to get this set up.

Prerequisites

You need to already know really quite a lot about what troggle does, and how it is used in practice. Also you will have installed quite a lot of the software such as tunnel, therion, survex etc. as documented in your laptop configuration. In particular read the information there about VS code and git.

This page is a work in progess. Text will be moved here from

http://expo.survex.com/repositories/troggle/.git/tree/README.txt

Installing linux

If you don't already know how to do this, then you should probably not be attempting to work on the troggle code. But in case you are an experienced linux user who has always had someone else set up the system for them, then Ubuntu is the easiest and more forgiving to install, either directly on the computer or inside WSL. Because we are using fairly old, stable releases of Django, you will want Ubuntu-20.04

Install in WSL on Windows 10.
Install Ubuntu 20.04 LTS.

and familiarise yourself with the directory structure on the expo server, which we will be duplicating (partly) as docmented in The Expo Server. We are not here doing a full install of all the software and scripts on the server, just the minimum to run, test and debug troggle on Django.

WSL on Windows

The standard documentation for Ubuntu or debian below all works, but you should first skim the Windows expo laptop configuration too. So far as expo software is concerned, WSL1 and WSL2 behave identically.

Why no Docker container?

Yes, it is true that this would greatly speed up on-boarding new programmers.

But there is the significant danger that containers would get copied around and deployed without being properly cleaned up: resulting in configuration drift and a snowflake server situation. File permissions are a big issue.

We should do both: create a Docker system for getting started, then transition programmers to script-based or recipe-based provisioning so that systems are rebuilt cleanly. CUYC (who also use Django) have a bash script which sets up a new django development system. We should copy that in the first instance. Alas, we haven't got around to doing any of this yet.

Installing python

Python is not installed by default usually, and in any case we need specific versions to be installed. For Ubuntu 20.04 the default is python3.9 but this is incompatible with standard debian Buster which is what is live on our server, so we also need python3.7 .

If you are planning on helping the migration of troggle from debian Buster (v10) to Bullseye (v11) then you will also want python3.8 .

sudo apt install python3 python3-pip
sudo apt install sqlite3 sqlite3-doc
sudo apt install survex
sudo apt install software-properties-common
sudo add-apt-repository ppa:deadsnakes/ppa
sudo apt install python3.7 python3.7-venv python3.7-doc binutils binfmt-support
cd /usr/bin
sudo ln -s python3 python
sudo ln -s pip3 pip

You will also definitely need sqlite3 even if you are planning to use another database. Sqlite3 is used by the test harness system.

Note that when you install survex it installs a shed load of packages that it needs.

We do not install Django at this point. We will be installing Django in a separate virtual environment (a 'venv'), not in the main linux system.

Creating folders and soft links

We need to have the folder structure that troggle expects. On your own machine you will have your own logon id, and you do not need to create an 'expo' user, but you do need to create folders where and an 'expo' user would have them. Make links there to wherever you have actually installed the repos. So if you have installed all your repos in /mnt/c/EXPO/, then you would need to do this:

cd ~
cd ..
sudo mkdir expo
cd expo
sudo ln -s /mnt/c/EXPO/expoweb expoweb
sudo ln -s /mnt/c/EXPO/troggle troggle
sudo ln -s /mnt/c/EXPO/loser loser
sudo ln -s /mnt/c/EXPO/drawings drawings
sudo ln -s /mnt/c/EXPO/expofiles expofiles
sudo ln -s /mnt/c/EXPO/expowebcache expowebcache
sudo mkdir expowebcache/3d
cd ..
ls -tlA expo

If you do not have a local copy of the 40GB /expofiles/, don't worry. Later on we can set 'EXPOFILESREMOTE = True' and your test system will use the live expofiles on expo.survex.com (read only).

Installing Django and troggle

The important point to note here is that unless you are doing something fairly trivial, or you are a git genius, it is sensible to set up a python virtual environments to hold duplicate copies of both troggle and Django code. Then you will be able to check very quickly that your edited version of troggle runs with old, current and pre-release versions of python and of Django; and you will more easily be able to manage problems with incompatible versions of Django plugins as installing and upgrading the dependent packages is very fast.

Installing a venv

We set up a venv specifically for python 3.7 (which is the standard version on our server which is running unmodified Buster (debian v10) and Django 2.2.19. See the standard python documentation on venv for python 3.7.12. You can upgrade the version of python installed within pip venv but not downgrade. So get that first venv installed right by explicitly stating the python version to create it python3.7 -m venv py37d22. Note that we are creating it as a sibling folder to /expoweb/ . Note also that up to now we have been using 'sudo ..' but for installing things inside the venv we do not use 'sudo ..':

cd ~
cd ../expo
python3.7 -m venv py37d22
cd py37d22
source bin/activate
pip list -o

The last command lists the default packages installed in the venv. This is for comparison later, after we have installed troggle, Django and dependencies. You will get a warning that you have an out of date version of pipbut this is as we want: we are using a version of pip appropriate for the older version of python within the venv. troggle logo

Installing the troggle dependencies

The first time you do this on a new machine you can't complete the pip installation of Django as you have not yet got the dependencies appropriate for troggle - because you have not yet cloned the troggle repo. So the first time it is easiest to just create requirements.txt yourself with a text editor. Without using git yourself, you can get the file from the website at requirements.txt. If you have already cloned all the repos, then just copy it.

cp ../troggle/requirements.txt .

where requirements.txt (note the capitalisation of the listed packages) is:

confusable-homoglyphs==3.2.0
Django==2.2
docutils==0.14
gunicorn==20.1.0
Pillow==5.4.1
pytz==2019.1
sqlparse==0.2.4
Unidecode==1.0.23

This will pick up the latest Django 2.2.x available, but all the other dependencies are pinned. These dependencies are as-standard on debian Buster (10) and you will want to experiment with upgrading them for Bullseye (v11).

Once you have the file, install the listed dependencies like this:

pip install -r requirements.txt
pip list -o

Pillow is an image handling package used to make the prospecting map (currently disabled, see /prospecting_guide/).
tinymce is the wysiwyg in-browser editor (disabled pending reinstatement)

This is also documented in the updating Django for troggle page where it describes upgrading and testing with later versions of Django.

If you have not used pip before, read this

Installing troggle

The :troggle: repo is the python source code for troggle. This is what you will be editing. There are over 8,000 lines of python code (excluding comments and blank lines) and over 2,000 lines of HTML/Django template code. This is over 600 files in over 400 folders, but only 38MB in size.

key exchange

Follow this link to register a key with the expo server to get git access if you have not already cloned the :troggle: repo.

git clone troggle

You will do a git clone to create a folder /troggle/ containing all the troggle code. You need to clone the 'python-3' branch, if you an see multiple branches.

cd ~
cd ../expo
git clone ssh://expo@expo.survex.com/home/expo/troggle

Now we create soft links within the venv to all the repo folders and wherever you have a local copy of /expofiles/ and /expowebcache/:

cd py37d22
sudo ln -s /mnt/c/EXPO/expoweb expoweb
sudo ln -s /mnt/c/EXPO/troggle troggle
sudo ln -s /mnt/c/EXPO/loser loser
sudo ln -s /mnt/c/EXPO/drawings drawings
sudo ln -s /mnt/c/EXPO/expofiles expofiles
sudo ln -s /mnt/c/EXPO/expowebcache expowebcache

If you have not been using git on this machine until now, you will need to identify yourself before you go any further.

git config --global user.email "you@example.com"
git config --global user.name "Your Name"

do the basic Django health checks

This all checks that the installation has completed properly.

django-admin

The first line django-admin will complain that it has not got a SETTINGS file, but that's fine. See django-admin initial output for what you should expect to see at this point. If it crashes though, you have not managed to install the software completely. If you get an error when running

django-admin

Then run django-admin like this (using the python version you have installed in the folder underneath /lib/):

python /usr/local/lib/python3.8/dist-packages/django/bin/django-admin.py

which should fix the paths, but this means that you installed Django directly on your machine and not in a venv. From now on you should be able to run django-admin from within any folder on your machine.

Now try

django-admin --version

The version number is the version of Django you have installed. Double check that it is the one you meant to install and check with our Django versions page.

do the basic troggle health checks

Now try

python manage.py

You will get an error: No module named 'localsettings'. Fixing this is described below, but for now try:

python manage.py check -v 3 --traceback

The most important is the python manage.py check. If this works, then you have installed the software correctly.

The next task is to edit the SETTINGS files to match your machine and folder structure. So find the appropriate copy of the localsettings in /_deploy/ and copy it into the main troggle folder:

cp _deploy/wsl/localsettingsWSL.py localsettings.py

The git repo copies have got munged passwords. localsettings.py is not stored in git, but the copy on the server does have the correct passwords. So use sFTP to download localsettings.py from expo.survex.com to get these.

We have at one time made localsettings in /_deploy/ appropriate for

debian (server install, not development)
Ubuntu
Ubuntu under WSL (Windows System for Linux)
docker container
potatohut (local network only)

WARNING: only the WSL and debian variants are current in December 2021. All the others are so old that they will need serious work to be useable. Copy what you need from WSL and debian variants of localsettings.py

Now edit localsettings.py and insert useful values for EXPOUSERPASS [e.g. cavey:beery], EXPOADMINUSERPASS [e.g. beery:cavey], SECRET_KEY. SECRET_KEY can be anything, it just has to be unique to each installation and invisible to anyone not a developer.

Set EMAIL_HOST and EMAIL_HOST_PASSWORD to an email account you control that can send email. Then troggle can email you when some things go wrong. This may mean having to set EMAIL_PORT and MAIL_USE_TLS too (this is not used in troggle currently). Set EXPOUSER_EMAIL and EXPOADMINUSER_EMAIL to your own email address while you are doing software development. All these will be different when troggle is deployed on the public server.

Now you need to edit the following settings in your localsettings.py file to match your development machine, e.g. if you have /expofiles/ mounted on another disc:

FILES = Path('/mnt/f/expofiles/')
EXPOFILES = Path('/mnt/f/expofiles/')

All the other settings (drawings, expoweb etc.) will work fine if they are parallel directories to the directory you installed troggle into. The troggle code can find out itself where it is living.

If you do not have a local copy of /expofiles/ (40 GB), you can use the expo server copy if you set:

EXPOFILESREMOTE = TRUE

and then the FILES and EXPOFILES setings will be ignored.

Now try this again:

python manage.py

and in addition to the [django] command list, you will now gets command lists for [auth], [contenttypes], [core], and [sessions]. These are the modules (plugins) loaaded into django. [core] is the core of troggle (but not all of it: the input file parsers are not in [core]).

Now:

python -Wall manage.py check

This loads the settings files and checks that all the Django packages and python libraries imports all work. It gives warnings of deprecated Django which should be fixed. You should not get any warnings on a fresh install on a new machine but you will see warning and error messages when you are trying to upgrade troggle to use later versions of Django.

python manage.py check -v 3 --traceback

Ideally this will list settings imports and then say
System check identified no issues (0 silenced).

If you get an error your python sys.path is probably not set correctly yet. Do

python -m site

when you are in your troggle directory to see the list of paths python looks for when it is searching for packages (both django and troggle).
Ensure that the path to the troggle/ directory is in the list. It should be at the top, which is where the current working directory is.

Now:

python  manage.py check -v 3 --deploy

which will give security warnings for deployment. You will get various middleware settings because we have not got https:// properly configured everywhere (we have unresolved issues with the Django admin control panel and https:// in October 2021) and a warning not to use DEBUG=true in deployment. We always have DEBUG=True set for troggle as otherwise the users get useless error messages. This is completely contrary to Django official security advice.

Click triangle to see security warnings in detail

?: (security.W001) You do not have 'django.middleware.security.SecurityMiddleware' 
in your MIDDLEWARE so the SECURE_HSTS_SECONDS, SECURE_CONTENT_TYPE_NOSNIFF, 
SECURE_BROWSER_XSS_FILTER, and SECURE_SSL_REDIRECT settings will have no effect.                         

?: (security.W012) SESSION_COOKIE_SECURE is not set to True. Using a secure-only 
session cookie makes it more difficult for network traffic sniffers to hijack user sessions.                                                                                           
?: (security.W016) You have 'django.middleware.csrf.CsrfViewMiddleware' in your 
MIDDLEWARE, but you have not set CSRF_COOKIE_SECURE to True. Using a secure-only 
CSRF cookie makes it more difficult for network traffic sniffers to steal the CSRF token.              

?: (security.W018) You should not have DEBUG set to True in deployment.

If you got an error traceback with

python manage.py

then the settings registration of troggle with django is incomplete. Delete all your cached .pyc files and try again. You probably have a mistake in your settings.py or localsettings.py files.

python manage.py diffsettings

This last one shows everything set in global settings, settings and localsettings. Anything different from global settings (django built-in) has '###' appended.

python manage.py help migrate
python manage.py migrate

Tests the uptodateness of your sqlite database. The help option explains what this does and gives extra command line options.

check full functionality

Now run the test suite:

python manage.py test -v 3 --traceback

This will run the entire troggle test suite of over 70 tests (it takes only a few seconds).

If you get an error, and you probably will, have a look in the source code of the test, e.g. for this error:

FAIL: test_page_folk (troggle.core.TESTS.tests.PageTests)

look in the file troggle/code/TESTS/tests.py in the class PageTests. It will also say:

  File "/mnt/c/EXPO/troggle/core/TESTS/tests.py", line 266, in test_page_folk

which means that the asssert failure in on line 266 of troggle/code/TESTS/tests.py and that the failure function is test_page_folk() . If you look at this you will see that line 264 is:

 response = self.client.get('/folk/index.htm')

so this file is missing. Duh. Of course it is. We downloaded troggle from git but we didn't run the standalone script to generate the folk list. The quickest thing to do when installing troggle is to simply download a copy from the server:

 wget -O ../expoweb/folk/index.htm expo.survex.com/folk/index.htm

and run the tests again:

python  manage.py test -v 2

Click on the triangle to see how to run the folk script. You don't need to do this now.

The folk generation script is top of the list in http://expo.survex.com/handbook/troggle/scriptscurrent.html#folk

So do this:

cd ../expoweb/folk
python ../scripts/make-folklist.py index.htm
cd ../../troggle

The test suite now tidies up after itself, so there should not be any temporary files left behind or local git commits that you will need to clean up.

Check parsing and importing

Nearly half the code deals with importing and parsing data, so you need to test that a full data import works. Run the full data import troggle$ python databaseReset.py reset R000. It should take about 5 minutes to import everything. See Troggle Full Import for what you should expect to see.

Use git to commit your edits

You need to know git. Sorry, but there it is. See our git repositories and our git cheat sheet.

Helpful database tools and scripts

The public server uses a MariaDB SQL database and development is usually done using a single-user sqlite database which is a standard Django option.

You will find it very, very useful to see what is going on if you look directly at the data in the database (just a single file in the sqlite case) and browse the data in the tables. This is vital when doing Django migrations between Django versions. A light-weight, simple db browser is DB Browser for SQLite. Connecting directly the the MariaDB database with a control panel or workbench gives even more tools and documentation capabilities. See the troggle server documentation for how to install MariaDB.

Go on to: Troggle architecture
Return to: Troggle programmers' guide
Troggle index: Index of all troggle documents