Building a zero-glue code web app with Starcounter
Marcin Warpechowski
Starcounter
June 2015
What is glue code?
glue code (uncountable)
(computing) Code that serves to connect separate parts of a program for compatibility or interoperability.
Considered necessary evil.
Why there is glue code
- Connects independent software components
- Connects black-box software, services, systems
Glue code between
software stack layers
Horizontal glue code between applications
Why there is glue code
- Connects independent software components
- Connects black-box software, services, systems
Where does it pile up
Data model
ORM
Business logic
Application logic
Service logic
Client view
Client logic
Microservices
Scalability-related
Glue code between software stack layers
LOC
DEV TIME
Where does it pile up
Glue code between applications
How do you deal with the need for glue code
Seek for patterns
Seek for patterns,
best practices
How do you deal with the need for glue code
Seek for patterns,
best practices,
frameworks &
tools
How do you deal with the need for glue code
Seek for patterns
best practices
frameworks &
tools,
conferences
How do you deal with the need for glue code
How much of code is glue?
From 25% to 95% of the code is glue code.
A line of glue code costs 3 times as much as a line of regular code.
Why glue code is an anti-pattern
- Leads to spaghetti code
-
UglyCreative hacks are here - Goes through endless reorganization/refactoring
- Likely to be thrown away at some point
- Leads to developer frustration
- Is a gray area of SLAs
- Often overlooked in development effort estimation
How to get
zero glue code
between application layers
Data Model
Controller
View Model
View
Data Model
Controller
View Model
View
Demo time
What we removed
Data model
ORM
Business logic
Application logic
Service logic
Client view
Client logic
Microservices
Scalability-related
Collapsing the stack
LOC
DEV TIME
What we left
Data model
Business logic
Application logic
Client view
Only the meaningful parts of your app
LOC
DEV TIME
How to get
zero glue code
between applications
Database and screen as the only integration points
Icons by Iris Sun, James Fenton / Noun Project
Partial app responses merged before sending to client
All apps bind or map to the same data model