This issue is related to #3107
This is a first renaming/refactoring step before reworking and removing heartbeats.
As discussed with @Liamsi , we preferred to go for a couple of independent and separate PRs to simplify review work.

The changes:

    Help to clarify the relation between the validator and remote signer endpoints
    Differentiate between timeouts and deadlines
    Prepare to encapsulate networking related code behind RemoteSigner in the next PR

My intention is to separate and encapsulate the "network related" code from the actual signer.

SignerRemote ---(uses/contains)--> SignerValidatorEndpoint <--(connects to)--> SignerServiceEndpoint ---> SignerService (future.. not here yet but would like to decouple too)

All reconnection/heartbeat/whatever code goes in the endpoints. Signer[Remote/Service] do not need to know about that.

I agree Endpoint may not be the perfect name. I tried to find something "Go-ish" enough. It is a common name in go-kit, kubernetes, etc.

Right now:
SignerValidatorEndpoint:

    handles the listener
    contains SignerRemote
    Implements the PrivValidator interface
    connects and sets a connection object in a contained SignerRemote
    delegates PrivValidator some calls to SignerRemote which in turn uses the conn object that was set externally

SignerRemote:

    Implements the PrivValidator interface
    read/writes from a connection object directly
    handles heartbeats

SignerServiceEndpoint:

    Does most things in a single place
    delegates to a PrivValidator IIRC.

* cleanup

* Refactoring step 1

* Refactoring step 2

* move messages to another file

* mark for future work / next steps

* mark deprecated classes in docs

* Fix linter problems

* additional linter fixes

* libs/common: TrapSignal accepts logger as a first parameter

 and does not block anymore
* previously it was dumping "captured ..." msg to os.Stdout
* TrapSignal should not be responsible for blocking thread of execution

Refs #3238

* exit with zero (0) code upon receiving SIGTERM/SIGINT

Refs #3238

* fix formatting in docs/app-dev/abci-cli.md

Co-Authored-By: melekes <anton.kalyaev@gmail.com>

* fix formatting in docs/app-dev/abci-cli.md

Co-Authored-By: melekes <anton.kalyaev@gmail.com>

* not related to linter: remove obsolete constants:
 - `Insecure` and `Secure` and type `Security` are not used anywhere

* not related to linter: update example

 - NewInsecure was deleted; change example to NewRemoteDB

* address: Binds to all network interfaces (gosec):

 - bind to localhost instead of 0.0.0.0
 - regenerate test key and cert for this purpose (was valid for ::) and
 otherwise we would see:
 transport: authentication handshake failed: x509: certificate is
 valid for ::, not 127.0.0.1\"

(used https://github.com/google/keytransparency/blob/master/scripts/gen_server_keys.sh
to regenerate certs)

* use sha256 in tests instead of md5; time difference is negligible

* nolint usage of math/rand in test and add comment on its import

 - crypto/rand is slower and we do not need sth more secure in tests

* enable linter in circle-ci

* another nolint math/rand in test

* replace another occurrence of md5

* consistent comment about importing math/rand

* make govet linter pass

Refs #3262

* close PipeReader and check for err

* WIP: Starts adding remote signer test harness

This commit adds a new command to Tendermint to allow for us to build a
standalone binary to test remote signers such as KMS
(https://github.com/tendermint/kms).

Right now, all it does is test that the local public key matches the
public key reported by the client, and fails at the point where it
attempts to get the client to sign a proposal.

* Fixes typo

* Fixes proposal validation test

This commit fixes the proposal validation test as per #3149. It also
moves the test harness into its own internal package to isolate its
exports from the `privval` package.

* Adds vote signing validation

* Applying recommendations from #3149

* Adds function descriptions for test harness

* Adds ability to ask remote signer to shut down

Prior to this commit, the remote signer needs to manually be shut down,
which is not ideal for automated testing. This commit allows us to send
a poison pill message to the KMS to let it shut down gracefully once
testing is done (whether the tests pass or fail).

* Adds tests for remote signer test harness

This commit makes some minor modifications to a few files to allow for
testing of the remote signer test harness. Two tests are added here:
checking for a fully successful (the ideal) case, and for the case where
the maximum number of retries has been reached when attempting to accept
incoming connections from the remote signer.

* Condenses serialization of proposals and votes using existing Tendermint functions

* Removes now-unnecessary amino import and codec

* Adds error message for vote signing failure

* Adds key extraction command for integration test

Took the code from here:
https://gist.github.com/Liamsi/a80993f24bff574bbfdbbfa9efa84bc7 to
create a simple utility command to extract a key from a local Tendermint
validator for use in KMS integration testing.

* Makes path expansion success non-compulsory

* Fixes segfault on SIGTERM

We need an additional variable to keep track of whether we're
successfully connected, otherwise hitting Ctrl+Break during execution
causes a segmentation fault. This now allows for a clean shutdown.

* Consolidates shutdown checks

* Adds comments indicating codes for easy lookup

* Adds Docker build for remote signer harness

Updates the `DOCKER/build.sh` and `DOCKER/push.sh` files to allow one to
override the image name and Dockerfile using environment variables.
Updates the primary `Makefile` as well as the `DOCKER/Makefile` to allow
for building the `remote_val_harness` Docker image.

* Adds build_remote_val_harness_docker_image to .PHONY

* Removes remote signer poison pill messaging functionality

* Reduces fluff code in command line parsing

As per
https://github.com/tendermint/tendermint/pull/3149#pullrequestreview-196171788,
this reduces the amount of fluff code in the PR down to the bare
minimum.

* Fixes ordering of error check and info log

* Moves remove_val_harness cmd into tools folder

It seems to make sense to rather keep the remote signer test harness in
its own tool folder (now rather named `tm-signer-harness` to keep with
the tool naming convention). It is actually a separate tool, not meant
to be one of the core binaries, but supplementary and supportive.

* Updates documentation for tm-signer-harness

* Refactors flag parsing to be more compact and less redundant

* Adds version sub-command help

* Removes extraneous flags parsing

* Adds CHANGELOG_PENDING entry for tm-signer-harness

* Improves test coverage

Adds a few extra parameters to the `MockPV` type to fake broken vote and
proposal signing. Also adds some more tests for the test harness so as
to increase coverage for failed cases.

* Fixes formatting for CHANGELOG_PENDING.md

* Fix formatting for documentation config

* Point users towards official Tendermint docs for tools documentation

* Point users towards official Tendermint docs for tm-signer-harness

* Remove extraneous constant

* Rename TestHarness.sc to TestHarness.spv for naming consistency

* Refactor to remove redundant goroutine

* Refactor conditional to cleaner switch statement and better error handling for listener protocol

* Remove extraneous goroutine

* Add note about installing tmkms via Cargo

* Fix typo in naming of output signing key

* Add note about where to find chain ID

* Replace /home/user with ~/ for brevity

* Fixes "signer.key" typo

* Minor edits for clarification for tm-signer-harness bulid/setup process

in the attempt to fix https://circleci.com/gh/tendermint/tendermint/43165

also

    code is simplified by running gofmt -s .
    remove unused vars
    enable linters we're currently passing
    remove deprecated linters

Because there's nothing worse than having to copy/paste a link from a
web page to navigate to it 😁

As per conversation here: https://github.com/tendermint/tendermint/pull/3218#discussion_r251364041

This is the result of running the following code on the repo:

```bash
find . -name '*.go' | grep -v 'vendor/' | xargs -n 1 goimports -w
```

This commit makes both EventNewBlock and EventNewBlockHeader emit tags
on the event bus, so subscribers can use them in queries.

* Fixed accepting integer IDs in requests for Tendermint RPC server (#2366)

* added a wrapper interface `jsonrpcid` that represents both string and int IDs in JSON-RPC requests/responses + custom JSON unmarshallers

* changed client-side code in RPC that uses it

* added extra tests for integer IDs

* updated CHANGELOG_PENDING, as suggested by PR instructions

* addressed PR comments

* added table driven tests for request type marshalling/unmarshalling
* expanded handler test to check IDs
* changed pending changelog note

* changed json rpc request/response unmarshalling to use empty interfaces and type switches on ID

* some cleanup

* Decouple StartHTTP{,AndTLS}Server from Listen()

This should help solve cosmos/cosmos-sdk#2715

* Fix small mistake

* Update StartGRPCServer

* s/rpc/rpcserver/

* Start grpccore.StartGRPCServer in a goroutine

* Reinstate l.Close()

* Fix rpc/lib/test/main.go

* Update code comment

* update changelog and comments

* fix tm-monitor. more comments

Refs #2693

bump alpine version to 3.8

* specify time unit for FlushThrottleTimeout in TestP2PConfig
Refs #2555
* [tm-bench] refactor code
https://github.com/tendermint/tendermint/pull/2405#pullrequestreview-157166387

Fixes #2409

* lean up Makefile and remove LICENSE file
* remove k8s and build LICENSE files
* remove non-existing target

Currently the top level directory contains basically all of the code
for the crypto package. This PR moves the crypto code into submodules
in a similar manner to what `golang/x/crypto` does. This improves code
organization.

Ref discussion: https://github.com/tendermint/tendermint/pull/1966

Closes #1956

This PR moves statistics to its own file, seperates getBlockMetas
into its own function, and removes the timeEnd parameter from
calculate statistics. The ending time is now computed directly from
the start time and the duration, to enforce that we only collect
data for the provided duration.

* tools/tm-bench: Don't count the first block if its empty

* Try melekes suggestion

* Fix getting the start time so the first block is no longer empty

* Fix changelog entry

* Make code smell better

* tools/tmbench: Fix the end time being used for statistics calculation

Previously we were using the time at which all connections closed in statistics, not
the time after {duration} seconds.

* Use waitgroups for starting up

make BlockMeta Header a non-pointer

Refs #693

At larger tx sizes (e.g. > 10000) we were spending non-neglible
amounts of time in tx creation, due to making the final bytes random.
The slower the send loop, the less accurate it is at measuring the time
tendermint took. (As we can't reach the promised contract of the given rate)

There really isn't much need for that randomness, so this PR makes it
such that only the txNumber gets bumped between txs from the same
connection, thereby improving sendloop speed and accuracy.

Previously we were using the time at which all connections closed in statistics, not
the time after {duration} seconds.

fixes for tools repo merge (#1943)