1.
Breaking down the monolith
Peter Marton, Trace by RisingStack

2.
whoami
work: CTO, Co-founder of RisingStack
twitter: slashdotpeter
email: peter@risingstack.com
blog: https://blog.risingstack.com

3.
agenda
1. Monolith and Microservices
2. Our experiences
3. Microservices challenges

4.
1. Monolith and
microservices

5.
monolith

6.
monolith
self-contained

7.
monolith
responsible for
multiple tasks

8.
monolith
independent from
other services

9.
microservice
https://microserviceweekly.com

10.
microservice
smaller services
each with separate DB
https://microserviceweekly.com

11.
microservice
split code by feature
not by functionality
https://microserviceweekly.com

12.
microservice
complexity in
network
https://microserviceweekly.com

13.
microservice
NOT FOR MVP!

14.
agenda
1. Monolith and Microservices
2. Our experiences
3. Microservices challenges

15.
What is Trace?
- I work on it
- Product by RisingStack
- Node.js and microservice monitoring tool
- Built with Node.js
- Built as a monolith in MVP phase

16.
Why we moved to
microservices?

17.
Why we moved?
growing engineering
team

18.
Why we moved?
separated features ->
focused people

19.
Why we moved?
need for
fault tolerance

20.
2. Our experiences

21.
Pros

22.
Well focused
independent teams (pro)

23.
Easier to scale a
specific part (pro)

24.
Easier to develop a
feature (pro)

25.
Features fails
independently (pro)

26.
Cons

27.
Increasing architectural
complexity (cons)

28.
Increasing
response times (cons)

29.
Harder to
test and deploy (cons)

30.
agenda
1. Monolith and Microservices
2. Our experiences
3. Microservices challenges

31.
3. Microservice
challenges

32.
Fault tolerance

33.
If monitoring goes down...
who knows that you are down?

34.
Fault tolerance
services
fail separately

35.
Fault tolerance
critical resources
should be cached

36.
Our service caching
- service level caching
- our service-lib handles it
- via cache headers

37.
Fault tolerance
temporary failures ->
persistent queues

38.
Fault tolerance
event sourcing
(not just microservices)

39.
~Event sourcing with queue

40.
Increasing complexity

41.
Where we started (~8 months ago)

42.
Where we are (today)

43.
What if it breaks?

44.
Logs everywhere

45.
Where is the issue?

46.
there...

47.
Distributed tracing
- Trace by RisingStack
- Zipkin
- Google Dapper white paper
- Transaction ID, Correlation ID

48.
Response time

49.
Even with very fast services

50.
...you can have a slow app
:(

51.
Because of network delays

52.
Network delay is evil
in microservices

53.
Keep your services
“close” to each other

54.
Proxy approach

55.
Proxy

56.
Proxy
- Re-route requests to services
- Authorize requests via access-service
- Decorate flippers (feature flag)
- Rewrite urls

57.
Proxy
- Evolutionary design (pro)
- Authentication in proxy (pro)
- Cookie handling at service (cons)
- Service format response for browser (cons)

58.
Services interfaces are
designed with browser in mind

59.
API Gateway

60.
API Gateway
Img: http://bits.citrusbyte.com/microservices

61.
API Gateway
- Everything that’s client(s) specific:
- Auth: Cookie headers, JWT token etc.
- Response format: JSON, XML etc.
- Combine resources: from multiple services

62.
Security

63.
Request signing
- Trusted sources (services) on public channel
- node-http-signature
- Built-in in request and super-request npm
modules
https://github.com/joyent/node-http-signature

64.
Request signing

65.
Service teams

66.
Your services are products
for your customers and co-workers!

67.
Service principles

68.
Service principles
max. three depth
call chains

69.
Service principles
always backward
compatible endpoints

70.
Service principles
do not version
services (only endpoints)

71.
Service principles
use feature toggles
heavily (flippers)

72.
Service principles
good to start here:
https://github.com/Yelp/service-principles

73.
Documented API(s)

74.
Documented API
enforce
documentation

75.
Documented API
update docs
together with code

76.
Documented API
make it available
for everyone

77.
Thanks!
https://trace.risingstack.com