* refactor TestRequestMessageFromMailboxAsync to use s.requestHistoricMessages helper
* send p2pRequestResponseCode from mailserver
* send p2p message response to after sending all historic messages
* mailserver sends `whisper.NewSentMessage` as response
* add mailserver Client and p2pRequestAckCode watchers
* send event with envelopeFeed when p2pRequestAckCode is received
* test request completed event in tracker
* rename mailserver response events and code to RequestCompleteCode
* wait for mailserver response in e2e test
* use SendHistoricMessageResponse method name for mailserver response
* fix lint warnings
* add mailserver request expiration
* send mailserver response without envelope
* add `ttl` to Request struct in shhext_requestMessages
* test that tracker calls handler.MailServerRequestExpired
* add geth patch
* rename TTL to Timeout
* split tracker.handleEvent in multiple methods
This change adds adds an ability to use different source of time for whisper:
when envelope is created it is used to set expiry
to track when envelope needs to be expired
This time is then used to check validity of the envelope when it is received. Currently If we receive an envelope that is sent from future - peer will get disconnected. If envelope that was received has an expiry less then now it will be simply dropped, if expiry is less than now + 10*2 seconds peer will get dropped.
So, it is clear that whisper depends on time. And any time we get a skew with peers that is > 20s reliability will be grealy reduced.
In this change another source of time for whisper will be used. This time source will use ntp servers from pool.ntp.org to compute offset. When whisper queries time - this offset will be added/substracted from current time.
Query is executed every 2 mins, queries 5 different servers, cut offs min and max and the computes mean value. pool.ntp.org is resolved to different servers and according to documentation you will rarely hit the same.
Closes: #687
* Add RequestMessage to sshext
* E2E tests now use shhext_requestMessages
* Typo in comment
* Enhanced maintainability
* Drop former mailservice
* Code reorg after review
* Fix missed changes after update to 1.8.5
Andrea Franz
Adrià Cidre
Igor Mandrigin
Pedro Pombeiro
Dmitry Shulyak
Frank Mueller