Best Practices With Distributed OSGi

8/12/2019 Best Practices With Distributed OSGi

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2002 IBM CorporationConfidential | Date | Other Information, if necessary

2009 by Marks !ppe, "cott #e$is% made a&ailable nder the '(# &)*0 | March 2+, 2009

Best Practices for Distributed OSGiServices

Markus Alexander KuppeScott Lewis

http!!www"eclipse"or#!ecf


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2009 by Marks le-ander !ppe, "cott #e$is% made a&ailable nder the '(# &)*0 | March 2+, 2009

$Isn't D-OSGi... just repeating themistake of every other RPC-

base system in the !ast "#years$ Dis%uss...%

http!!twitter"co&!n'bartlett


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$Isn't D-OSGi... just repeating the

mistake of every other RPC-

base system in the !ast "#

years$

(O)**+t,s our 'ob to &ake sure of this"""and the 'ob,s not finished


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(etwork 6ransparenc3

Do 3ou hide the network,s aspects fro& the pro#ra&&er7

Perfor&ance!6i&in#

5eliabilit3!Partial 8ailure

Nota #ood idea

/A (ote on Distributed 9o&putin#

/ Lots of failed atte&pts at doin# so - See (eil,s tweet

One conclusion 4ventuall3"""pro#ra&&ers of distributed service clientswant to knowand reactto what,s happenin#
http://research.sun.com/techrep/1994/abstract-29.htmlhttp://research.sun.com/techrep/1994/abstract-29.html


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4nter OSGi Services

(ow have OSGi Service 5e#istr3!Service5eference!Service5e#istration

/ 6he fra&ework &ana#es service re#istration!lookup!and cleanup

. bundle9ontext"re#isterService0"""1

.bundle9ontext"#etService5eferences0"""1

. bundle9ontext"stop01

Makes 5e#istration2 Lookup2 9lean-up work

589 ::; provide transparentre&ote service re#istration2 lookup2 and

clean-up


7/17 2009 by Marks le-ander !ppe, "cott #e$is% made a&ailable nder the '(# &)*0 | March 2+, 2009

6his is GOOD 6ransparenc3

Makes it ver3 eas3 for pro#ra&&ers to use - GOOD

Providers 0i&ple&entations1 take care of the hard stuff 0distribution2seriali



But there is also Usage6ransparenc3

Public M35esult foo0M3Para&eter1=

9lients will expect it to work when the3 call it

+t,s #oin# to fail with 5unti&e4xception"""or worse2 block

6his willbe &uch &ore fre.uent than local services

>hat are clients to do7

Usage6ransparenc3"""Still a problem for those that design service

interface



6ransparent Usage0cont1

'C 4xposes +5e&oteServicevia service propert3 os#i"re&ote

Gives prox3 A(D additional callin# patterns to service consu&er

As3nc4xec2 8uture2 One->a3

.1emote"er&iceracker

Sa&e 8unctionalit3 as Service6racker

+5e&oteService rather than Ob'ect
http://www.eclipse.org/ecf/org.eclipse.ecf.docs/api/org/eclipse/ecf/remoteservice/IRemoteService.htmlhttp://www.eclipse.org/ecf/org.eclipse.ecf.docs/api/org/eclipse/ecf/remoteservice/util/tracker/RemoteServiceTracker.htmlhttp://www.eclipse.org/ecf/org.eclipse.ecf.docs/api/org/eclipse/ecf/remoteservice/util/tracker/RemoteServiceTracker.htmlhttp://www.eclipse.org/ecf/org.eclipse.ecf.docs/api/org/eclipse/ecf/remoteservice/IRemoteService.html


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Discover3 best practice forservice consu&ers

(O(4)*

*+t,s our 'ob to &ake sure of this"""and it,s done -1

9annot run discover3 s3nchronousl3 upon

getServi%eReferen%es01 as it violates thenon-blockin# nature of OSGi


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Discover3 best practice forservice providers

(O(4)*

*+t,s our 'ob to &ake sure of this"""and it,s nearl3 done -1

?owever2 what,s with non ::; relevant

service props7"""securit32 &arshallin#


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8or service providers or consu&er innon-OSGi based s3ste&s and deplo3ers

. @ou i#nore discover3 entirel3 0'ust static confi#uration1 -1

. 8ind a wa3 to +nte#rate with existin# solutions/ SLP2 &D(S2 D(S-SD2 DD+2 +(+2 C proprietar3

. 9hose a protocol that best fits 3our re.uire&ents

. Deal with all the protocol2 network""" details/ ?ave network specialist!ad&inistrators on the tea&

. Do not trust service discover3 events 0unless 3ou secured it1


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589 ::;v outlook

. Different DS> in one runti&e all handle a service re#istered

event7/ >hat is the discover3 provider supposed to do7 Onl3 handle

service publication for its &atchin# DS>7 8or all7

. ?ow to do authentication7/ Make services available that won,t be consu&able because of

access restrictions

. Bein# &ore as3nchronous in distributed OSGi as well as thefra&ework itself7


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'clipse 'C (ro3ect

Thanks spec writersThanks Scott Rosenbaum for making this talk happen

Questions?

http455$$$*eclipse*or65ecfhttp455$iki*eclipse*or65'C


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Best Practices With Distributed OSGi

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