When dates chosen for billing report are not in the same
financial year, API throws an error. This error was not being
caught so far. This PR starts to catch it and display a banner
with error message on the page, instead of page crashing.
This commit makes an abstract base class for broadcast areas, so that
methods and properties which are common between `BroadcastArea`s (those
which come from our library) and `CustomBroadcastArea`s (those supplied
via the API) can be shared.
If an area has a `count_of_phones` value of `0` it means we don’t have
data about the population.
This means we can’t do the maths to work out the estimated bleed. So we
should return the default amount of bleed of 1,500m instead, which is
something in between what we’d expect for a built up area and a rural
area.
This prevents us from giving unrealistically large or small bleed
estimates in case we have areas which are more dense or less dense than
the most/least dense areas we currently have.
Also means we don’t have to treat City of London as a special case.
We don’t vary this between different environments so it doesn’t need to
be in the config.
I was trying to look up what this value was and found it a bit confusing
that it was spread across multiple places.
There are basically two kinds of 4G masts:
Frequency | Range | Bandwidth
----------|-------------|----------------------------------
800MHz | Long (500m) | Low (can handle a bit of traffic)
1800Mhz | Short (5km) | High (can handle lots of traffic)
The 1800Mhz masts are better in terms of how much traffic they can
handle and how fast a connection they provide. But because they have
quite short range, it’s only economical to install them in very built up
areas†.
In more rural areas the 800MHz masts are better because they cover a
wider area, and have enough bandwidth for the lower population density.
The net effect of this is that cell broadcasts in rural areas are likely
to bleed further, because the masts they are being broadcast from are
less precise.
We can use population density as a proxy for how likely it is to be
covered by 1800Mhz masts, and therefore how much bleed we should expect.
So this commit varies the amount of bleed shown based on the population
density.
I came up with the formula based on 3 fixed points:
- The most remote areas (for example the Scottish Highlands) should have
the highest average bleed, estimated at 5km
- An town, like Crewe, should have about the same bleed as we were
estimating before (1.5km) – Pete D thinks this is about right based on
his knowledge of the area around his office in Crewe
- The most built up areas, like London boroughs, could have as little as
500m of bleed
Based on these three figures I came up with the following formula, which
roughly gives the right bleed distance (`b`) for each of their population
densities (`d`):
```
b = 5900 - (log10(d) × 1_250)
```
Plotted on a curve it looks like this:
This is based on averages – remember that the UI shows where is _likely_
to receive the alert, based on bleed, not where it’s _possible_ to
receive the alert.
Here’s what it looks like on the map:
---
†There are some additional subtleties which make this not strictly true:
- The 800Mhz masts are also used in built up areas to fill in the gaps
between the areas covered by the 1800Mhz masts
- Switching between masts is inefficient, so if you’re moving fast
through a built up area (for example on a train) your phone will only
use the 800MHz masts so that you have to handoff from one mast to
another less often
now that we no longer set it since
https://github.com/alphagov/notifications-admin/pull/3841 was merged, we
don't need to remove it either. And we can remove checks that expect it
when cleaning up the session. And the unit tests that make sure we
ignore it if it's in the session.
So long, session['invited_user'] and session['invited_org_user']!
Previously each navigation class had a list of endpoint to "exclude",
which was only used in tests to ensure that all endpoints in the app
were covered: either they are present in navigation, or excluded.
However, over time the "exclude" lists have grown long and repetitive,
and maintaining each of them individually adds extra work [1][2]. This
switches to a more DRY approach, where the list of excluded endpoints
is defined once, close to the single point of use in the test.
Note the resulting test is _slightly_ less prescriptive, as it will now
pass if an endpoint exist one in navigation, even if it should also
exist in another. This seems a reasonable compromise.
[1]: https://github.com/alphagov/notifications-admin/pull/3788/files#r572809972
[2]: https://github.com/alphagov/notifications-admin/pull/3794/files#diff-39387df3a9f89b313976957e7b5457be20deab1017b2d895541b142b957f1972
the invited_user objects can be arbitrarily large, and when we put them
in the session we risk going over the session cookie's 4kb size limit.
since https://github.com/alphagov/notifications-admin/pull/3827 was
merged, we store the user id in the session. Now that's been live for a
day or two we can safely stop putting the rich object in the session.
Needed to change a bunch of tests for this to make sure appropriate
mocks were set. Also some tests were accidentally re-using fake_uuid.
Still pop the object when cleaning up sessions. We'll need to remove
that in a future PR.
The `/accounts` page was listing trial mode services twice if a user
belonged to an org. They were shown under both the 'Live services' and
'Trial mode services' sections. After this change, 'Live services' will
show all live services (whether or not they belong to an org) and 'Trial
mode services' will show all trial mode services. If a user belongs to an
org, they will also see the summary of how many services per org at the
top of the page.
A couple of services in tests were renamed for clarity.
We used to upload this to performance platform to show the list of
services and organisations.
There is no longer a performance platform to upload this file to.
The performance page expects all live services to have an organisation.
This should be true on production, but it isn’t always the case in
other environments.
When the organisation name is `None`, the frontend can’t sort the list
of organisations alphabetically and so raises an exception.
