Post on 20-May-2020
Moving to Microservices:
Visualising Technical Debt,
Kubernetes, and GraphQL with Michelle Krejci
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Moving to Microservices:
Visualising Technical
Debt, Kubernetes, and
GraphQL
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HE
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I have been on a journey of discovery
through a difficult challenge of upgrading a
successful but inflexible monolithic system and I want to tell you how I have approached
this problem in part by leveraging the
capabilities of Kubernetes and GraphQL and
other fun toys which sound good in a
presentation proposal.
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Here is a compressed 30 minute tutorial
and some
incantations you can use when you get back to
your office
of
how to use these things
that will solve all of your
problems and guarantee that you feel good
about coming to this talk.
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I’ll wait.
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6
Michelle
Software Engineer @getpantheon
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Let’s start with the ending.
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Build how
you build on
pace with what
you build.
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Build how
you build on
pace with what
you build.
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Act 1
Build it quick.
Actual footage of an early stage startup.
Everyone has the same resources.
Every team member is working on building a viable product that won’t tip over.
The build process is: have an idea, try it, see if it can stand up + people like it.
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Pantheon at this stage
Frontend
(node.js)
Monolith
(twistd python)
Two languages
Two repositories
Two prod environments
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How we build
Dev on
clone of
prod
Push to
Master
runs CI
Jenkins
kicks off
Chef
run
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We did it!
Now, no one touch it.
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Act 2
When you
need to touch
it.
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At this stage, should the existing
production system
be the spec?
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Write a bunch of
tests to check that if it’s not this -------------
-------->
it’s broken.
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feature or bug?
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Break up what
you build
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Moving to Microservices:
Visualising Technical
Debt, Kubernetes, and
GraphQL
PA
NT
HE
ON
.IO
Pantheon at this stage
Frontend
(node.js)
Monolith
(twistd python)
Service A
(python)
Service B
(python)
Service C
(go)
Service C
(go)
Many languages
Many repos
Many prod environments
WINS
Domains that can be event
driven are a good starting
place.
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But this will force
you to change how you build
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Moving to Microservices:
Visualising Technical
Debt, Kubernetes, and
GraphQL
PA
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HE
ON
.IO
How we build
Dev on
clone of
prod -
copied
into k8
ns
Push to
branch
runs CI
CI
builds
image +
pushes
CI
applies
k8s
config
Service
defines
build with
common
make
WINS
Common repo of Makefiles
Leverage namespaces in
k8s
Internal tool for building dev
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Cool but...
feature or bug?
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Act 3
The Spec.
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Ideal specs
unrealistic testing suites
artifacts of an optimistic past
are used to build
that add so much friction they became
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#I don’t know how it
#works but don’t
#touch it. Trust me.
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Moving to Microservices:
Visualising Technical
Debt, Kubernetes, and
GraphQL
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#I don’t know how it
#works but don’t
#touch it. Trust me.
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{
Antenna(id: "123") {
marshmallow {
fluffiness
}
spaghetti {
}
}
}
{
MiddleBit(id: "123") {
spaghetti(id: “456”) {
bendiness
}
}
}
{
Base(id: "123") {
tape {
length
}
}
}
Client Backend
s
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Pantheon at this stage
Frontend
(node.js)
Monolith
(twistd python)
Service A
(python)
Service B
(python)
Service C
(go)
Service C
(go)
REST→ GraphQL
Schema-first
API Gateway to strangle monolith
API Gateway
(Apollo Server)
Schema
{
[...]
}
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How we build
Dev on
clone of
prod -
copied
into k8
ns
Push to
branch
runs CI
CI
builds
image +
pushes
CI
applies
k8s
config
Service
defines
build with
common
make
Define
schema Check
against
schema
Update
to
schema
merged
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Act 4
The Exit.
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Switch to language the rest of the business
understands.
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So you want to exit...
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soon-
ish.
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But you have a
gap.
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Maybe you can fill
that gap by adding
new features!
Cool
thing
1
Cool
thing
1
Cool
thing
2
Cool
thing
3
Cool
thing
2
Cool
thing
1
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Moving to Microservices:
Visualising Technical
Debt, Kubernetes, and
GraphQL
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“if you develop a program for a long period of time by only adding
features and never reorganizing it
to reflect your understanding of
those features, then eventually that
program simply does not contain any understanding and all efforts to work
on it take longer and longer”
- Ward Cunningham
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Maybe you can fill
that gap by adding
new features…?
Cool
thing
1
Cool
thing
1
Cool
thing
2
Cool
thing
3
Cool
thing
2
Cool
thing
1
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Cool thing 1
If you have not built
your build on pace...
probably not.
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You need to invest in
teams to ship the
things.
Cool
team
1
Cool
team
2
Cool
team
3
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AND you’re going to
build infrastructure to
support the product
being shipped.
Cool
Thing
1
Cool
Thing
2
Cool
Thing
3
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AND you’re going to build
the tools to support the
infrastructure that
supports the product
being shipped.
Cool
Thing
1
Cool
Thing
2
Cool
Thing
3
Cool
Tool
1
Cool
Tool
2
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AND you’re going to need
teams to support the tools
that support the
infrastructure that supports
the product being
shipped....
Cool
Thing
1
Cool
Thing
2
Cool
Thing
3
Cool
Tool
1
Cool
Tool
2
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Sales knows to grow their team and
their process as complexity
increases.
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Build how
you build on
pace with what
you build.
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Incidentally,
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I am terrible at this.
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@mcraychee