chcko 0.1.5

chcko randomly parameterized exercises automatically checked (formerly mamchecker)

chcko

Educational content server.

Content Packages

Content packages are separate python packages within the same chcko namespace. An example package is https://github.com/chcko/chcko-r. This is a technical example without didactic thread.

Content packages consist of small content items

• short explanations

• problems with randomly generated values

• courses as path through explanations and problems (TODO)

Content items are identified in the URL with <author_id>.<content_id>, each short, and correspond to the folder chcko/<author_id>/<content_id>/ within the content package. The item folder contains __init__.py and <language_id>.html files.

<language_id>.rst are also possible. They can contain tikz images and are statically converted to _<language_id>.html with:

doit -kd. html
doit -kd. initdb

The server can run on

• on gcloud (currently: https://mamchecker.appspot.com)

• on any other server using sqlalchemy

Updating content on gcloud (TODO):

• a content package is registered in requirements.txt via pull request

• a content package author uploads a new version to https://pypi.org

• regularly a new version of chcko is deployed (once a day or whenever a content package has changed on pypi)

Implementation

Python 3 using bottle. The code tries to stay minimal.

Database:

The data model is:

school 1-n period 1-n teacher 1-n class 1-n student 1-n problem

The first 5 are called a context or role. A user has more contexts.

DB for answers to problems

• on GCP using DataStore with ndb or

• on any other server using a SQL database with SqlAlchemy

Templates:

• bottle SimpleTemplate

The URL format is, e.g <...>/en/content?r.bd&r.ba&r.a:

URL = "https://"domain"/"lang"/"page_request"
domain = "chcko-262117.appspot.com"
lang = "en"|"de"|...
page_request = ["content?"]{author"."exercise["="count]"&"}
             | "done?"context{field("~"|"="|"!"|"<"|">")value","}
             | "todo"
             | "edits?"("new"|"change"|"delete")
             | "contexts"
context = [[[[[school&]period&]teacher&]class&]student&]

Courses: && instead of one & is a separator. &&& marks the current position. E.g. <...>/en/content?r.bd&&r.ba&&&r.a has r.a as current item in the course. Sequence is the other variant: all in one page.

Pages:

• content: overview or items composed via URL

• contexts: contexts of one user

• done: done exercises filtered by context

• todo: assigned exercises

• some additional helper pages

Environment Variables

CHCKOSECRET:

a secret used to encode the user token cookie

CHCKOPORT:

used to change port for local server

SOCIAL_AUTH_<PROVIDER>_KEY:

for social login

SOCIAL_AUTH_<PROVIDER>_SECRET:

for social login

Commands

Install Google Cloud SDK:

cd ~/.local/opt/
curl -OLs https://dl.google.com/dl/cloudsdk/channels/rapid/downloads/google-cloud-sdk-274.0.0-linux-x86_64.tar.gz
tar -xf google-cloud-sdk-274.0.0-linux-x86_64.tar.gz
rm google-cloud-sdk-274.0.0-linux-x86_64.tar.gz
cd google-cloud-sdk
./install.sh

#new terminal
gcloud components install cloud-datastore-emulator cloud-firestore-emulator beta
#link with google account
gcloud init --console-only
#gcloud projects delete <sample-project-id>

Clone and initialize chcko:

cd ~/mine
git clone https://github.com/chcko/chcko
git clone https://github.com/chcko/chcko-r #sample content
pip install --user doit

Pepare content:

cd ~/mine/chcko-r/chcko/r
doit -kd. html
cd ~/mine/chcko-r
doit initdb

Virtual environment:

source .nox/test_sql/bin/activate
deactivate

Test chcko:

# unit tests
cd ~/mine/chcko
make test
make cov
doit test
doit cov
nox

# not installed tests (check "r.dj" for images)
# on other CLI:
# gcloud beta emulators datastore start --no-store-on-disk --data-dir .
# check test routes in app.py

./runchcko_with_sql.py

#if OSError: [Errno 98] Address already in use
export CHCKOPORT=8382
./runchcko_with_sql.py

./runchcko_with_ndb.py

cd ~/mine
python2 `which dev_appserver.py` chcko                                                                                                                          0(∞)

# install test
pip uninstall chcko-r
pip uninstall chcko
~/mine/chcko
pip install --user .
~/mine/chcko-r
pip install --user .
cd
runchcko

#breakpoint() in code
cd chcko
py.test chcko/chcko/tests/test_functional.py --db=sql
b chcko/chcko/app.py:90
c

Upload:

cd ~/mine/chcko
gcloud app deploy app.yaml

gcloud commands (see reference):

gcloud help
gcloud info --format yaml
gcloud auth {list,login,revoke}
gcloud config {list,set {account,project},configurations list}
gcloud components {list,install,update,remove}
gcloud app {browse,deploy,describe,deploy,open-console}

gcloud app open-console opens the GCP console in the browser.