Using ABCI-CLI
|
|
==============
|
|
|
|
To facilitate testing and debugging of ABCI servers and simple apps, we
|
|
built a CLI, the ``abci-cli``, for sending ABCI messages from the
|
|
command line.
|
|
|
|
Install
|
|
-------
|
|
|
|
Make sure you `have Go installed <https://golang.org/doc/install>`__.
|
|
|
|
Next, install the ``abci-cli`` tool and example applications:
|
|
|
|
::
|
|
|
|
go get -u github.com/tendermint/abci/cmd/abci-cli
|
|
|
|
If this fails, you may need to use `dep <https://github.com/golang/dep>`__ to get vendored
|
|
dependencies:
|
|
|
|
::
|
|
|
|
cd $GOPATH/src/github.com/tendermint/abci
|
|
make get_tools
|
|
make get_vendor_deps
|
|
make install
|
|
|
|
Now run ``abci-cli`` to see the list of commands:
|
|
|
|
::
|
|
|
|
Usage:
|
|
abci-cli [command]
|
|
|
|
Available Commands:
|
|
batch Run a batch of abci commands against an application
|
|
check_tx Validate a tx
|
|
commit Commit the application state and return the Merkle root hash
|
|
console Start an interactive abci console for multiple commands
|
|
counter ABCI demo example
|
|
deliver_tx Deliver a new tx to the application
|
|
kvstore ABCI demo example
|
|
echo Have the application echo a message
|
|
help Help about any command
|
|
info Get some info about the application
|
|
query Query the application state
|
|
set_option Set an options on the application
|
|
|
|
Flags:
|
|
--abci string socket or grpc (default "socket")
|
|
--address string address of application socket (default "tcp://127.0.0.1:46658")
|
|
-h, --help help for abci-cli
|
|
-v, --verbose print the command and results as if it were a console session
|
|
|
|
Use "abci-cli [command] --help" for more information about a command.
|
|
|
|
|
|
KVStore - First Example
|
|
-----------------------
|
|
|
|
The ``abci-cli`` tool lets us send ABCI messages to our application, to
|
|
help build and debug them.
|
|
|
|
The most important messages are ``deliver_tx``, ``check_tx``, and
|
|
``commit``, but there are others for convenience, configuration, and
|
|
information purposes.
|
|
|
|
We'll start a kvstore application, which was installed at the same time as
|
|
``abci-cli`` above. The kvstore just stores transactions in a merkle tree.
|
|
|
|
Its code can be found `here <https://github.com/tendermint/abci/blob/master/cmd/abci-cli/abci-cli.go>`__ and looks like:
|
|
|
|
.. container:: toggle
|
|
|
|
.. container:: header
|
|
|
|
**Show/Hide KVStore Example**
|
|
|
|
.. code-block:: go
|
|
|
|
func cmdKVStore(cmd *cobra.Command, args []string) error {
|
|
logger := log.NewTMLogger(log.NewSyncWriter(os.Stdout))
|
|
|
|
// Create the application - in memory or persisted to disk
|
|
var app types.Application
|
|
if flagPersist == "" {
|
|
app = kvstore.NewKVStoreApplication()
|
|
} else {
|
|
app = kvstore.NewPersistentKVStoreApplication(flagPersist)
|
|
app.(*kvstore.PersistentKVStoreApplication).SetLogger(logger.With("module", "kvstore"))
|
|
}
|
|
|
|
// Start the listener
|
|
srv, err := server.NewServer(flagAddrD, flagAbci, app)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
srv.SetLogger(logger.With("module", "abci-server"))
|
|
if err := srv.Start(); err != nil {
|
|
return err
|
|
}
|
|
|
|
// Wait forever
|
|
cmn.TrapSignal(func() {
|
|
// Cleanup
|
|
srv.Stop()
|
|
})
|
|
return nil
|
|
}
|
|
|
|
Start by running:
|
|
|
|
::
|
|
|
|
abci-cli kvstore
|
|
|
|
And in another terminal, run
|
|
|
|
::
|
|
|
|
abci-cli echo hello
|
|
abci-cli info
|
|
|
|
You'll see something like:
|
|
|
|
::
|
|
|
|
-> data: hello
|
|
-> data.hex: 68656C6C6F
|
|
|
|
and:
|
|
|
|
::
|
|
|
|
-> data: {"size":0}
|
|
-> data.hex: 7B2273697A65223A307D
|
|
|
|
An ABCI application must provide two things:
|
|
|
|
- a socket server
|
|
- a handler for ABCI messages
|
|
|
|
When we run the ``abci-cli`` tool we open a new connection to the
|
|
application's socket server, send the given ABCI message, and wait for a
|
|
response.
|
|
|
|
The server may be generic for a particular language, and we provide a
|
|
`reference implementation in
|
|
Golang <https://github.com/tendermint/abci/tree/master/server>`__. See
|
|
the `list of other ABCI
|
|
implementations <./ecosystem.html>`__ for servers in
|
|
other languages.
|
|
|
|
The handler is specific to the application, and may be arbitrary, so
|
|
long as it is deterministic and conforms to the ABCI interface
|
|
specification.
|
|
|
|
So when we run ``abci-cli info``, we open a new connection to the ABCI
|
|
server, which calls the ``Info()`` method on the application, which
|
|
tells us the number of transactions in our Merkle tree.
|
|
|
|
Now, since every command opens a new connection, we provide the
|
|
``abci-cli console`` and ``abci-cli batch`` commands, to allow multiple
|
|
ABCI messages to be sent over a single connection.
|
|
|
|
Running ``abci-cli console`` should drop you in an interactive console
|
|
for speaking ABCI messages to your application.
|
|
|
|
Try running these commands:
|
|
|
|
::
|
|
|
|
> echo hello
|
|
-> code: OK
|
|
-> data: hello
|
|
-> data.hex: 0x68656C6C6F
|
|
|
|
> info
|
|
-> code: OK
|
|
-> data: {"size":0}
|
|
-> data.hex: 0x7B2273697A65223A307D
|
|
|
|
> commit
|
|
-> code: OK
|
|
|
|
> deliver_tx "abc"
|
|
-> code: OK
|
|
|
|
> info
|
|
-> code: OK
|
|
-> data: {"size":1}
|
|
-> data.hex: 0x7B2273697A65223A317D
|
|
|
|
> commit
|
|
-> code: OK
|
|
-> data.hex: 0x49DFD15CCDACDEAE9728CB01FBB5E8688CA58B91
|
|
|
|
> query "abc"
|
|
-> code: OK
|
|
-> log: exists
|
|
-> height: 0
|
|
-> value: abc
|
|
-> value.hex: 616263
|
|
|
|
> deliver_tx "def=xyz"
|
|
-> code: OK
|
|
|
|
> commit
|
|
-> code: OK
|
|
-> data.hex: 0x70102DB32280373FBF3F9F89DA2A20CE2CD62B0B
|
|
|
|
> query "def"
|
|
-> code: OK
|
|
-> log: exists
|
|
-> height: 0
|
|
-> value: xyz
|
|
-> value.hex: 78797A
|
|
|
|
Note that if we do ``deliver_tx "abc"`` it will store ``(abc, abc)``,
|
|
but if we do ``deliver_tx "abc=efg"`` it will store ``(abc, efg)``.
|
|
|
|
Similarly, you could put the commands in a file and run
|
|
``abci-cli --verbose batch < myfile``.
|
|
|
|
Counter - Another Example
|
|
-------------------------
|
|
|
|
Now that we've got the hang of it, let's try another application, the
|
|
"counter" app.
|
|
|
|
Like the kvstore app, its code can be found `here <https://github.com/tendermint/abci/blob/master/cmd/abci-cli/abci-cli.go>`__ and looks like:
|
|
|
|
.. container:: toggle
|
|
|
|
.. container:: header
|
|
|
|
**Show/Hide Counter Example**
|
|
|
|
.. code-block:: go
|
|
|
|
func cmdCounter(cmd *cobra.Command, args []string) error {
|
|
|
|
app := counter.NewCounterApplication(flagSerial)
|
|
|
|
logger := log.NewTMLogger(log.NewSyncWriter(os.Stdout))
|
|
|
|
// Start the listener
|
|
srv, err := server.NewServer(flagAddrC, flagAbci, app)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
srv.SetLogger(logger.With("module", "abci-server"))
|
|
if err := srv.Start(); err != nil {
|
|
return err
|
|
}
|
|
|
|
// Wait forever
|
|
cmn.TrapSignal(func() {
|
|
// Cleanup
|
|
srv.Stop()
|
|
})
|
|
return nil
|
|
}
|
|
|
|
|
|
The counter app doesn't use a Merkle tree, it just counts how many times
|
|
we've sent a transaction, asked for a hash, or committed the state. The
|
|
result of ``commit`` is just the number of transactions sent.
|
|
|
|
This application has two modes: ``serial=off`` and ``serial=on``.
|
|
|
|
When ``serial=on``, transactions must be a big-endian encoded
|
|
incrementing integer, starting at 0.
|
|
|
|
If ``serial=off``, there are no restrictions on transactions.
|
|
|
|
We can toggle the value of ``serial`` using the ``set_option`` ABCI
|
|
message.
|
|
|
|
When ``serial=on``, some transactions are invalid. In a live blockchain,
|
|
transactions collect in memory before they are committed into blocks. To
|
|
avoid wasting resources on invalid transactions, ABCI provides the
|
|
``check_tx`` message, which application developers can use to accept or
|
|
reject transactions, before they are stored in memory or gossipped to
|
|
other peers.
|
|
|
|
In this instance of the counter app, ``check_tx`` only allows
|
|
transactions whose integer is greater than the last committed one.
|
|
|
|
Let's kill the console and the kvstore application, and start the counter
|
|
app:
|
|
|
|
::
|
|
|
|
abci-cli counter
|
|
|
|
In another window, start the ``abci-cli console``:
|
|
|
|
::
|
|
|
|
> set_option serial on
|
|
-> code: OK
|
|
|
|
> check_tx 0x00
|
|
-> code: OK
|
|
|
|
> check_tx 0xff
|
|
-> code: OK
|
|
|
|
> deliver_tx 0x00
|
|
-> code: OK
|
|
|
|
> check_tx 0x00
|
|
-> code: BadNonce
|
|
-> log: Invalid nonce. Expected >= 1, got 0
|
|
|
|
> deliver_tx 0x01
|
|
-> code: OK
|
|
|
|
> deliver_tx 0x04
|
|
-> code: BadNonce
|
|
-> log: Invalid nonce. Expected 2, got 4
|
|
|
|
> info
|
|
-> code: OK
|
|
-> data: {"hashes":0,"txs":2}
|
|
-> data.hex: 0x7B22686173686573223A302C22747873223A327D
|
|
|
|
This is a very simple application, but between ``counter`` and
|
|
``kvstore``, its easy to see how you can build out arbitrary application
|
|
states on top of the ABCI. `Hyperledger's
|
|
Burrow <https://github.com/hyperledger/burrow>`__ also runs atop ABCI,
|
|
bringing with it Ethereum-like accounts, the Ethereum virtual-machine,
|
|
Monax's permissioning scheme, and native contracts extensions.
|
|
|
|
But the ultimate flexibility comes from being able to write the
|
|
application easily in any language.
|
|
|
|
We have implemented the counter in a number of languages (see the
|
|
`example directory <https://github.com/tendermint/abci/tree/master/example`__).
|
|
|
|
To run the Node JS version, ``cd`` to ``example/js`` and run
|
|
|
|
::
|
|
|
|
node app.js
|
|
|
|
(you'll have to kill the other counter application process). In another
|
|
window, run the console and those previous ABCI commands. You should get
|
|
the same results as for the Go version.
|
|
|
|
Bounties
|
|
--------
|
|
|
|
Want to write the counter app in your favorite language?! We'd be happy
|
|
to add you to our `ecosystem <https://tendermint.com/ecosystem>`__!
|
|
We're also offering `bounties <https://tendermint.com/bounties>`__ for
|
|
implementations in new languages!
|
|
|
|
The ``abci-cli`` is designed strictly for testing and debugging. In a
|
|
real deployment, the role of sending messages is taken by Tendermint,
|
|
which connects to the app using three separate connections, each with
|
|
its own pattern of messages.
|
|
|
|
For more information, see the `application developers
|
|
guide <./app-development.html>`__. For examples of running an ABCI
|
|
app with Tendermint, see the `getting started
|
|
guide <./getting-started.html>`__. Next is the ABCI specification.
|