serve.go

// Copyright 2017 Monax Industries Limited
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//    http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package commands

import (
	"fmt"
	"os"
	"os/signal"
	"path"
	"syscall"

	"github.com/monax/burrow/core"
	"github.com/monax/burrow/definitions"
	"github.com/monax/burrow/logging"
	"github.com/monax/burrow/logging/lifecycle"
	"github.com/monax/burrow/util"
	vm "github.com/monax/burrow/manager/burrow-mint/evm"

	"github.com/spf13/cobra"
)

const (
	DefaultConfigBasename = "config"
	DefaultConfigType     = "toml"
)

var DefaultConfigFilename = fmt.Sprintf("%s.%s",
	DefaultConfigBasename,
	DefaultConfigType)

// build the serve subcommand
func buildServeCommand(do *definitions.Do) *cobra.Command {
	cmd := &cobra.Command{
		Use:   "serve",
		Short: "burrow serve starts an burrow node with client API enabled by default.",
		Long: `burrow serve starts an burrow node with client API enabled by default.
The burrow node is modularly configured for the consensus engine and application
manager.  The client API can be disabled.`,
		Example: fmt.Sprintf(`$ burrow serve -- will start the burrow node based on the configuration file "%s" in the current working directory
$ burrow serve --work-dir <path-to-working-directory> -- will start the burrow node based on the configuration file "%s" in the provided working directory
$ burrow serve --chain-id <CHAIN_ID> -- will overrule the configuration entry assert_chain_id`,
			DefaultConfigFilename, DefaultConfigFilename),
		PreRun: func(cmd *cobra.Command, args []string) {
			// if WorkDir was not set by a flag or by $BURROW_WORKDIR
			// NOTE [ben]: we can consider an `Explicit` flag that eliminates
			// the use of any assumptions while starting burrow
			if do.WorkDir == "" {
				if currentDirectory, err := os.Getwd(); err != nil {
					panic(fmt.Sprintf("No directory provided and failed to get current "+
						"working directory: %v", err))
					os.Exit(1)
				} else {
					do.WorkDir = currentDirectory
				}
			}
			if !util.IsDir(do.WorkDir) {
				panic(fmt.Sprintf("Provided working directory %s is not a directory",
					do.WorkDir))
				os.Exit(1)
			}
		},
		Run: ServeRunner(do),
	}
	addServeFlags(do, cmd)
	return cmd
}

func addServeFlags(do *definitions.Do, serveCmd *cobra.Command) {
	serveCmd.PersistentFlags().StringVarP(&do.ChainId, "chain-id", "c",
		defaultChainId(), "specify the chain id to use for assertion against the genesis file or the existing state. If omitted, and no id is set in $CHAIN_ID, then assert_chain_id is used from the configuration file.")
	serveCmd.PersistentFlags().StringVarP(&do.WorkDir, "work-dir", "w",
		defaultWorkDir(), "specify the working directory for the chain to run.  If omitted, and no path set in $BURROW_WORKDIR, the current working directory is taken.")
	serveCmd.PersistentFlags().StringVarP(&do.DataDir, "data-dir", "",
		defaultDataDir(), "specify the data directory.  If omitted and not set in $BURROW_DATADIR, <working_directory>/data is taken.")
	serveCmd.PersistentFlags().BoolVarP(&do.DisableRpc, "disable-rpc", "",
		defaultDisableRpc(), "indicate for the RPC to be disabled. If omitted the RPC is enabled by default, unless (deprecated) $BURROW_API is set to false.")
}

//------------------------------------------------------------------------------
// functions
func NewCoreFromDo(do *definitions.Do) (*core.Core, error) {
	// load the genesis file path
	do.GenesisFile = path.Join(do.WorkDir,
		do.Config.GetString("chain.genesis_file"))

	if do.Config.GetString("chain.genesis_file") == "" {
		return nil, fmt.Errorf("The config value chain.genesis_file is empty, " +
			"but should be set to the location of the genesis.json file.")
	}
	// Ensure data directory is set and accessible
	if err := do.InitialiseDataDirectory(); err != nil {
		return nil, fmt.Errorf("Failed to initialise data directory (%s): %v", do.DataDir, err)
	}

	loggerConfig, err := core.LoadLoggingConfigFromDo(do)
	if err != nil {
		return nil, fmt.Errorf("Failed to load logging config: %s", err)
	}

	// Create a root logger to pass through to dependencies
	logger := logging.WithScope(lifecycle.NewLoggerFromLoggingConfig(loggerConfig), "Serve")
	// Capture all logging from tendermint/tendermint and tendermint/go-*
	// dependencies
	lifecycle.CaptureTendermintLog15Output(logger)
	// And from stdlib go log
	lifecycle.CaptureStdlibLogOutput(logger)

	// if do.ChainId is not yet set, load chain_id for assertion from configuration file

	if do.ChainId == "" {
		if do.ChainId = do.Config.GetString("chain.assert_chain_id"); do.ChainId == "" {
			return nil, fmt.Errorf("The config chain.assert_chain_id is empty, " +
				"but should be set to the chain_id of the chain we are trying to run.")
		}
	}

	logging.Msg(logger, "Loading configuration for serve command",
		"chainId", do.ChainId,
		"workingDirectory", do.WorkDir,
		"dataDirectory", do.DataDir,
		"genesisFile", do.GenesisFile)

	consensusConfig, err := core.LoadConsensusModuleConfig(do)
	if err != nil {
		return nil, fmt.Errorf("Failed to load consensus module configuration: %s.", err)
	}

	managerConfig, err := core.LoadApplicationManagerModuleConfig(do)
	if err != nil {
		return nil, fmt.Errorf("Failed to load application manager module configuration: %s.", err)
	}

	logging.Msg(logger, "Modules configured",
		"consensusModule", consensusConfig.Version,
		"applicationManager", managerConfig.Version)

	return core.NewCore(do.ChainId, consensusConfig, managerConfig, logger)
}

// ServeRunner() returns a command runner that prepares the environment and sets
// up the core for burrow to run. After the setup succeeds, it starts the core
// and waits for the core to terminate.
func ServeRunner(do *definitions.Do) func(*cobra.Command, []string) {
	return func(cmd *cobra.Command, args []string) {
		// load configuration from a single location to avoid a wrong configuration
		// file is loaded.
		err := do.ReadConfig(do.WorkDir, DefaultConfigBasename, DefaultConfigType)
		if err != nil {
			util.Fatalf("Fatal error reading configuration from %s/%s", do.WorkDir,
				DefaultConfigFilename)
		}

		vm.SetDebug(do.Debug)

		newCore, err := NewCoreFromDo(do)

		if err != nil {
			util.Fatalf("Failed to load core: %s", err)
		}

		if !do.DisableRpc {
			serverConfig, err := core.LoadServerConfig(do)
			if err != nil {
				util.Fatalf("Failed to load server configuration: %s.", err)
			}
			serverProcess, err := newCore.NewGatewayV0(serverConfig)
			if err != nil {
				util.Fatalf("Failed to load servers: %s.", err)
			}
			err = serverProcess.Start()
			if err != nil {
				util.Fatalf("Failed to start servers: %s.", err)
			}
			_, err = newCore.NewGatewayTendermint(serverConfig)
			if err != nil {
				util.Fatalf("Failed to start Tendermint gateway")
			}
			<-serverProcess.StopEventChannel()
		} else {
			signals := make(chan os.Signal, 1)
			signal.Notify(signals, syscall.SIGINT, syscall.SIGTERM)
			fmt.Fprintf(os.Stderr, "Received %s signal. Marmots out.", <-signals)
		}
	}
}

//------------------------------------------------------------------------------
// Defaults

func defaultChainId() string {
	// if CHAIN_ID environment variable is not set, keep do.ChainId empty to read
	// assert_chain_id from configuration file
	return setDefaultString("CHAIN_ID", "")
}

func defaultWorkDir() string {
	// if BURROW_WORKDIR environment variable is not set, keep do.WorkDir empty
	// as do.WorkDir is set by the PreRun
	return setDefaultString("BURROW_WORKDIR", "")
}

func defaultDataDir() string {
	// As the default data directory depends on the default working directory,
	// wait setting a default value, and initialise the data directory from serve()
	return setDefaultString("BURROW_DATADIR", "")
}

func defaultDisableRpc() bool {
	// we currently observe environment variable BURROW_API (true = enable)
	// and default to enabling the RPC if it is not set.
	// TODO: [ben] deprecate BURROW_API across the stack for 0.12.1, and only disable
	// the rpc through a command line flag --disable-rpc
	return !setDefaultBool("BURROW_API", true)
}