dedup with spec/abci/client-server

This commit is contained in:
zramsay 2018-10-06 15:11:20 -04:00
parent cdc252b818
commit 0a0fbd3bfe

View File

@ -47,90 +47,6 @@ The mempool and consensus logic act as clients, and each maintains an
open ABCI connection with the application, which hosts an ABCI server. open ABCI connection with the application, which hosts an ABCI server.
Shown are the request and response types sent on each connection. Shown are the request and response types sent on each connection.
## Message Protocol
The message protocol consists of pairs of requests and responses. Some
messages have no fields, while others may include byte-arrays, strings,
or integers. See the `message Request` and `message Response`
definitions in [the protobuf definition
file](https://github.com/tendermint/tendermint/blob/develop/abci/types/types.proto),
and the [protobuf
documentation](https://developers.google.com/protocol-buffers/docs/overview)
for more details.
For each request, a server should respond with the corresponding
response, where order of requests is preserved in the order of
responses.
## Server
To use ABCI in your programming language of choice, there must be a ABCI
server in that language. Tendermint supports two kinds of implementation
of the server:
- Asynchronous, raw socket server (Tendermint Socket Protocol, also
known as TSP or Teaspoon)
- GRPC
Both can be tested using the `abci-cli` by setting the `--abci` flag
appropriately (ie. to `socket` or `grpc`).
See examples, in various stages of maintenance, in
[Go](https://github.com/tendermint/tendermint/tree/develop/abci/server),
[JavaScript](https://github.com/tendermint/js-abci),
[Python](https://github.com/tendermint/tendermint/tree/develop/abci/example/python3/abci),
[C++](https://github.com/mdyring/cpp-tmsp), and
[Java](https://github.com/jTendermint/jabci).
### GRPC
If GRPC is available in your language, this is the easiest approach,
though it will have significant performance overhead.
To get started with GRPC, copy in the [protobuf
file](https://github.com/tendermint/tendermint/blob/develop/abci/types/types.proto)
and compile it using the GRPC plugin for your language. For instance,
for golang, the command is `protoc --go_out=plugins=grpc:. types.proto`.
See the [grpc documentation for more details](http://www.grpc.io/docs/).
`protoc` will autogenerate all the necessary code for ABCI client and
server in your language, including whatever interface your application
must satisfy to be used by the ABCI server for handling requests.
### TSP
If GRPC is not available in your language, or you require higher
performance, or otherwise enjoy programming, you may implement your own
ABCI server using the Tendermint Socket Protocol, known affectionately
as Teaspoon. The first step is still to auto-generate the relevant data
types and codec in your language using `protoc`. Messages coming over
the socket are proto3 encoded, but additionally length-prefixed to
facilitate use as a streaming protocol. proto3 doesn't have an
official length-prefix standard, so we use our own. The first byte in
the prefix represents the length of the Big Endian encoded length. The
remaining bytes in the prefix are the Big Endian encoded length.
For example, if the proto3 encoded ABCI message is 0xDEADBEEF (4
bytes), the length-prefixed message is 0x0104DEADBEEF. If the proto3
encoded ABCI message is 65535 bytes long, the length-prefixed message
would be like 0x02FFFF....
Note this prefixing does not apply for grpc.
An ABCI server must also be able to support multiple connections, as
Tendermint uses three connections.
## Client
There are currently two use-cases for an ABCI client. One is a testing
tool, as in the `abci-cli`, which allows ABCI requests to be sent via
command line. The other is a consensus engine, such as Tendermint Core,
which makes requests to the application every time a new transaction is
received or a block is committed.
It is unlikely that you will need to implement a client. For details of
our client, see
[here](https://github.com/tendermint/tendermint/tree/develop/abci/client).
Most of the examples below are from [kvstore Most of the examples below are from [kvstore
application](https://github.com/tendermint/tendermint/blob/develop/abci/example/kvstore/kvstore.go), application](https://github.com/tendermint/tendermint/blob/develop/abci/example/kvstore/kvstore.go),
which is a part of the abci repo. [persistent_kvstore which is a part of the abci repo. [persistent_kvstore