[LRUG] Continuous * (Happy New Year!)

[Samuel Joseph]

Hi LRUG,

Happy New Year!  Hope you all had a good one.

Apologies in advance for what has become a bit of a long post, but I 
have a question about "Continuous *", i.e.

* Continous Integration (C.I.)
* Continous Deployment
* Continous Delivery

I think I understand Continuous Integration quite well.  I take it to 
mean that all tests are run whenever you commit code to version 
repositories in the cloud, and thus we talk about C.I. providers such as 
Travis, Semaphore, CircleCI, CodeShip etc.   I interact with Travis and 
Semaphore on a daily basis and see the results of automated tests run on 
all our pull requests and again when we merge them in.  I think 
technically the concept of C.I. originally means just having all 
developers getting their work merged in to the same place with high 
frequency, but anyway, I feel relatively comfortable with this term.

The way I hear Continuous Deployment being used seems to be when the 
C.I. tests are set such that on a passing build, the code gets 
automatically deployed to a server.   We have a few pipelines where we 
have develop, staging and production servers, which are automatically 
deployed to as a result of passing builds on the develop, staging and 
master branches respectively.  These deployments are supported by hooks 
on Travis, Semaphore etc. and are very handy.  Continous Delivery I'm 
not so sure - I just found the term of google

Of course I have read the wikipedia pages on all these terms:

https://en.wikipedia.org/wiki/Continuous_integration
https://en.wikipedia.org/wiki/Continuous_deployment
https://en.wikipedia.org/wiki/Continuous_delivery

and while I'd love to tune up my mental pictures of each, what I'm 
really looking for the right term for the practise of automatically 
moving code along a pipeline like the one I mentioned above: develop --> 
staging --> production.

At the moment the process of running tests and deploying to each server 
for each branch is completely automatic.  However, the process of moving 
code from develop to staging, or staging to production is manual.  We've 
previously reached out to Travis, Semaphore and Heroku to ask about some 
process that would automate moves along the pipeline, but the 
conversation seems confused by the ambiguity in the technology and I'm 
left thinking they don't - but could be wrong.

We've recenly moved one pipeline completely from heroku to azure/dokku 
and it seems like we can now create our own automatic pipeline 
progression with cron jobs so that, say, on Monday at noon, the develop 
code is rebased into staging, and at noon on wednesday the staging code 
is rebased into production, and in each cases tests and deploys would be 
kicked off.   My main motivation to automate this is to remove the 
manual step which is a chore and can get put off.  It's particularly 
highlighted by our use of dependabot, which is automatically putting in 
PRs based on library upgrades, so every week there is a several upgrades 
to go out along with the usual features and bug-fixes.

I speculate that if we had such a setup, we'd get into the habit of 
being more careful with merging PRs (knowing they'd be automatically 
deployed to production) and regularly doing the few additional front end 
manual sanity checks when we're notified of staging and production 
deploys ...  Anyway, I'd love to know if there's a correct term to be 
using to describe the pipeline automation we want to set up, and whether 
there are any providers that make it easy to do.

We hear all the time about facebook, netflix etc. deploying to 
production multiple times a day, but I'm very interested to hear about 
practices at all scales.  Sorry for the long post - here's wishing 
everyone a very prosperous 2019!

Best, Sam