leanix graphql lessons learned - codetalks 2017
Post on 23-Jan-2018
349 Views
Preview:
TRANSCRIPT
GraphQLLessons LearnedBernd Schönbach, Patrick Surrey
LeanIX GmbH
Agenda
2
Introduction• Aboutus• AboutLeanIX• AboutGraphQL
WhyGraphQL?
GraphiQL
APIDesign
GraphQL ClientDesign
Apollo
Mutations
N+1SelectIssue
ExceptionHandling
About Us
3
PatrickSurrey BerndSchönbach
About LeanIX
4
5
• Shortertimetomarket• Real-timebigdatainsights• Efficientscalability• Exceptionaluserexperience• Consistentchannels• Integratedworkflows• …
More• APIs• Devices• Sensors
ITArchitecturesaremoreimportantthaneverbefore
LeanIXisthemostcomfortablesolution– asSaaS
6
AvailableIntegrations
7
Industrials&Manufacturing
Financial&Insurance Consumer
Energy&Materials Pharma
TravelLogistics
MediaTelecoms
INTERNATIONALEXPANSION
Well-knownbrandsofallindustriestrustinLeanIX
LeanIXisbasedonamodernMicroservices Stack
8
Pathfinder
Postgres
Elasticsearch
ArangoDB
PathfinderUISinglePageApp•Angular(2)•Typescript
BackendServices•GraphQL orRESTAPI•oAuth2/wJWT•SwaggerAPIDocs•Event-Bus(Webhooks)
Resources•Nosharingacrossservices•DeploymentwithDocker
Web-hooks MTM Export Image
s Survey Metric
Postgres
Kafka
Postgres
Shibbo
leth
PhantomJS
Postgres
Elasticsearch
Influ
xDB
“PlatformServices”
GraphQL
About GraphQL
9
10
“A query language for your API”http://graphql.org/
11
History
• 2012nativemobileclientforNewsFeed
• Early2015announcedpublicly(https://www.youtube.com/watch?v=9sc8Pyc51uU)
• Sep.2015officiallyopensourced
• Nov.2016:Manymoreusers
12
Basicidea
Server
WHATisavailable
Client
WHICHdataisneeded
1.Schema
2.Datarequirements
Java,Node,Ruby,PHP,Go,Scala,
.NET…
SimpleHTTP-Client
http://graphql.org/code/
Why GraphQL?
13
Why GraphQL?
14
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
Why GraphQL?
15
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
Why GraphQL?
16
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
Why GraphQL?
17
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
Why GraphQL?
18
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
query {id name type releasealias description...on Application {lifecycles {}relToSuccessor {}relToPredecessor {}relToBusinessCapability {}relToUserGroups {}[...]
}}
Why GraphQL?
19
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
query {id name type releasealias description
}
Why GraphQL?
20
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
query {id name
}
query {id name alias
}
query {id name description
}
Why GraphQL?
21
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
query {id name...on Application {lifecycles {}relToBusinessCapabilities {}relToUserGroups {}
}}
GRAPHIQL
GraphiQL –Interactive in-browserGraphQL IDE
23
Runqueries
Integrated ExploreAPI
Seeresult
GraphiQL
24
• Available here:https://github.com/graphql/graphiql
• Greatway to document and explore the API
• Very helpfull during devolpment,e.g.for quickly testing the API
à Get it up and running from day one!
APIDESIGN
Connections– InspiredbyRelayFramework
26
{"id": "factsheet-123”,"tags": [{ "id": "tag-1", "label": "Tag 1" },{ "id": "tag-2", "label": "Tag 2" }, { "id": "tag-3", "label": "Tag 3" }
]}
{idtags { id label }
}
FactSheet
Tag
Tag
Tag
Connections
27
{"id": "factsheet-123”,"tags": {
"edges": [{ "node": { "id": "tag-1", "label": "Tag 1" } },{ "node": { "id": "tag-2", "label": "Tag 2" } }, { "node": { "id": "tag-3", "label": "Tag 3" } }
]}
}
{idtags {
edges {node { id label }
}}
}
FactSheet
Tag
Tag
Tag
Connections- Advantages
28
{idtags {
totalCountpageInfo { startCursor endCursor hasNextPage }edges {
node { id label }}
}}
Connections- Advantages
29
{idtags {permissions { create read update delete }edges {node { id label }
}}
}
Connections– Lessonslearned
30
• MakestheAPImoregraphlike
• Usetheconnectionpatternrightfromthestart
• PreventsbreakingchangesinAPI
• UsethesamepatternthroughouttheAPI
• Clientscanhandleconnectionsinthesameway
APIDesign– No“deadends”
31
{idtagId
}
{idtag { id label }
}
APIDesign– Generallessonslearned
32
• APIdesignshouldbenottoousecasespecific
• YAGNI(„Youaren‘tgonna needit“)isusuallyagoodadvice,butshould
notbeappliedhere
• GraphQL isadvertisedas„...givesclientsthepowertoaskforexactly
whattheyneed“sodonotartificiallyrestricttheAPI
GRAPHQL CLIENTDESIGN
Doomed to fail ...
34
Lotsofparameters
Nobodydarestotouchthis
Evenmoregeneric
GraphQL client – Querybuilding
35
Noparameters
Simple!:-)
Helpertomakerequests
APOLLO
What about the ApolloClient?
37
• ApolloClientavailablehere:
https://github.com/apollographql/apollo-client
• “Afully-featured,productionreadycachingGraphQL clientforevery
serverorUIframework”
• DeepintegrationpossiblewithReact,Angular,iOS,Android,…
What about the ApolloClient?
38
So,what about it then?
39
• Didyouuseit?
• No,itwasnotavailablewhenwestarted…
• Wouldyouuseit?
• Perhaps- itofferssomeniceabstractions(queriescanberestarted
forinstance),butourownverysimplisticapproachworksverywell
atthemoment
Mutations
40
Mutations
41
Mutation createApplication(name: “Application A“, alias: „APP-A“) { namealias
}
GraphQL Suggests:
Mutations
42
Mutation createFactSheet(input: {name: “Application A“, type: Application
}, patches: $patches) { namealias
}
Query:
{ patches: [{op:“add“, path:“/alias“, value:“APP-A“}
]}
Variables:
N+1SelectIssue
43
What is the N+1SelectIssue?
44
Application application =appDAO.getApplication();
for(Successor successor:application.getSucessors()){System.out.println(“Successor:“+successor.getName());}
Application application =appDAO.getApplication();
for(Successor successor:application.getSucessors()){System.out.println(“Successor:“+successor.getName());}
SELECT*FROMapplication WHERE...SELECT*FROMapplication WHERE...
SELECT*FROMsuccessor WHEREid =successor.id;SELECT*FROMsuccessor WHEREid =successor.id;SELECT*FROMsuccessor WHEREid =successor.id;...
#Selects
1
N
+SELECT*FROMsuccessor WHEREid =successor.id;SELECT*FROMsuccessor WHEREid =successor.id;SELECT*FROMsuccessor WHEREid =successor.id;...
Why dowe have this issue with GraphQL?
45
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
Why dowe have this issue with GraphQL?
46
• JavaLibraryuses Datafetcher
• Is afunction to connect GraphQL to underlying DB
• Knows only his level
Why dowe have this issue with GraphQL?
47
Application {idnametypereleasealiasdescriptionLifecycles {...}Relations {SuccessorsPredecessorsBusiness CapabilitiesUser Groups[...]
}[...]
}
idnametypereleasealiasdescriptionLifecyclesRelations
idnametypereleasealiasdescriptionLifecyclesRelations
Why dowe have this issue with GraphQL?
48
• No context awareness
• No easyimplementation dueto „everything is agraph“
• Needsmanual implementation to fix.
How To Solve This
49
• Prediction Library(enable context awareness)
• Batching
• Caching
• Facebooks solution is called relay
Exception Handling
50
Exception Handling
51
• Exceptions of JavaGraphQL Libraryare useless
• “Anerror occurred“
• You need context information to show usefull exceptions
• We implemented our own handler for that
Conclusion
52
Conclusion
53
• Stop thinking inREST
• No dead ends
• GrahpiQL first
• GraphQL is notthe solution for erverything
Breaking News
54
Breaking News
55
Breaking News
56
https://medium.com/@dwalsh.sdlr/using-graphql-why-facebook-now-owns-you-3182751028c9
Breaking News
57
https://code.facebook.com/posts/121714468491809/relicensing-the-graphql-specification/
Thank You
Questions?
Slides are available at:
https://de.slideshare.net/leanIX_net
Sources
• http://williamdurand.fr/2014/02/14/please-do-not-patch-like-an-idiot/
• http://graphql.org/
• https://github.com/graphql/graphiql
• https://www.leanix.net/de
• https://www.apollodata.com
• https://github.com/graphql-java/graphql-java
• https://angular.io/
• https://facebook.github.io/relay/
top related