django: Demo app created

[rohany]

This PR updates the testing infrastructure to have the underlying tables
be a bit more flexibly named for the ORM, along with adding the example
code for Django.

[cockroach-teamcity]

This change is 

[rohany]

This is ready for a review, I was able to get the sqlalchemy tests working again

[rohany]

friendly ping

[rafiss]

Reviewable status: 0 of 15 files reviewed, 4 unresolved discussions (waiting on @jordanlewis, @rafiss, and @rohany)

---

python/django/cockroach_example/models.py, line 15 at r1 (raw file):

    id = models.AutoField(primary_key=True)
    subtotal = models.DecimalField(max_digits=18, decimal_places=2)
    # TODO (rohany): is setting null the right thing here? The schema doesn't say what to do. 

i think it would be fine to just make this cascade delete. that seems like the most basic thing to do here, and i think this demo app is just about showing off the most rudimentary ORM examples

---

python/django/cockroach_example/settings.py, line 88 at r1 (raw file):

DATABASES = {
    'default': {
        # 'ENGINE' : 'django.db.backends.postgresql',

do we need the commented line?

---

python/django/cockroach_example/views.py, line 21 at r1 (raw file):

            customers = list(Customers.objects.values())
        else:
            customers = list(Customers.objects.filter(id=id).values())

question from my inexperience: is this is how you do a PK lookup in django?

---

python/django/cockroach_example/views.py, line 29 at r1 (raw file):

        c = Customers(name=name)
        c.save()
        return HttpResponse(status=200)

doesn't really matter since it's just a demo app, but shouldn't the customer ID be returned back to the caller here? same for the other POST methods. this might not be worth changing if it would require other test infra changes

[rohany]

Reviewable status: 0 of 15 files reviewed, 4 unresolved discussions (waiting on @jordanlewis and @rafiss)

---

python/django/cockroach_example/models.py, line 15 at r1 (raw file):

Previously, rafiss (Rafi Shamim) wrote…

i think it would be fine to just make this cascade delete. that seems like the most basic thing to do here, and i think this demo app is just about showing off the most rudimentary ORM examples

Done.

---

python/django/cockroach_example/settings.py, line 88 at r1 (raw file):

Previously, rafiss (Rafi Shamim) wrote…

do we need the commented line?

nop

---

python/django/cockroach_example/views.py, line 21 at r1 (raw file):

Previously, rafiss (Rafi Shamim) wrote…

question from my inexperience: is this is how you do a PK lookup in django?

this is how you do any generic field lookup. to use the default primary key, you'd do .filter(pk=whatever) here.

---

python/django/cockroach_example/views.py, line 29 at r1 (raw file):

Previously, rafiss (Rafi Shamim) wrote…

doesn't really matter since it's just a demo app, but shouldn't the customer ID be returned back to the caller here? same for the other POST methods. this might not be worth changing if it would require other test infra changes

The test harness doesn't use the ID's at all (it seems to treat them as hidden values), and does lookups only by name.

[rohany]

PTAL

[rafiss]

lgtm! i just had another question but i'm fine going either way on it

Reviewable status: 0 of 15 files reviewed, 5 unresolved discussions (waiting on @jordanlewis, @rafiss, and @rohany)

---

python/django/cockroach_example/migrations/0001_initial.py, line 1 at r1 (raw file):

# Generated by Django 2.2.6 on 2019-10-02 18:35

just noticed this was generated -- should it be gitignored?

[rohany]

No, migrations are always checked into Django repositories. Does this repo have bors?

bors r+

[craig]

🔒 Permission denied

Existing reviewers: click here to make rohany a reviewer

[rohany]

F