path: root/cmd/swarm/config.go

// Copyright 2017 The go-ethereum Authors
// This file is part of go-ethereum.
//
// go-ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// go-ethereum is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.

package main

import (
    "errors"
    "fmt"
    "io"
    "os"
    "reflect"
    "strconv"
    "strings"
    "unicode"

    cli "gopkg.in/urfave/cli.v1"

    "github.com/ethereum/go-ethereum/cmd/utils"
    "github.com/ethereum/go-ethereum/common"
    "github.com/ethereum/go-ethereum/log"
    "github.com/ethereum/go-ethereum/node"
    "github.com/naoina/toml"

    bzzapi "github.com/ethereum/go-ethereum/swarm/api"
)

var (
    //flag definition for the dumpconfig command
    DumpConfigCommand = cli.Command{
        Action:      utils.MigrateFlags(dumpConfig),
        Name:        "dumpconfig",
        Usage:       "Show configuration values",
        ArgsUsage:   "",
        Flags:       app.Flags,
        Category:    "MISCELLANEOUS COMMANDS",
        Description: `The dumpconfig command shows configuration values.`,
    }

    //flag definition for the config file command
    SwarmTomlConfigPathFlag = cli.StringFlag{
        Name:  "config",
        Usage: "TOML configuration file",
    }
)

//constants for environment variables
const (
    SWARM_ENV_CHEQUEBOOK_ADDR = "SWARM_CHEQUEBOOK_ADDR"
    SWARM_ENV_ACCOUNT         = "SWARM_ACCOUNT"
    SWARM_ENV_LISTEN_ADDR     = "SWARM_LISTEN_ADDR"
    SWARM_ENV_PORT            = "SWARM_PORT"
    SWARM_ENV_NETWORK_ID      = "SWARM_NETWORK_ID"
    SWARM_ENV_SWAP_ENABLE     = "SWARM_SWAP_ENABLE"
    SWARM_ENV_SWAP_API        = "SWARM_SWAP_API"
    SWARM_ENV_SYNC_ENABLE     = "SWARM_SYNC_ENABLE"
    SWARM_ENV_ENS_API         = "SWARM_ENS_API"
    SWARM_ENV_ENS_ADDR        = "SWARM_ENS_ADDR"
    SWARM_ENV_CORS            = "SWARM_CORS"
    SWARM_ENV_BOOTNODES       = "SWARM_BOOTNODES"
    GETH_ENV_DATADIR          = "GETH_DATADIR"
)

// These settings ensure that TOML keys use the same names as Go struct fields.
var tomlSettings = toml.Config{
    NormFieldName: func(rt reflect.Type, key string) string {
        return key
    },
    FieldToKey: func(rt reflect.Type, field string) string {
        return field
    },
    MissingField: func(rt reflect.Type, field string) error {
        link := ""
        if unicode.IsUpper(rune(rt.Name()[0])) && rt.PkgPath() != "main" {
            link = fmt.Sprintf(", check github.com/ethereum/go-ethereum/swarm/api/config.go for available fields")
        }
        return fmt.Errorf("field '%s' is not defined in %s%s", field, rt.String(), link)
    },
}

//before booting the swarm node, build the configuration
func buildConfig(ctx *cli.Context) (config *bzzapi.Config, err error) {
    //check for deprecated flags
    checkDeprecated(ctx)
    //start by creating a default config
    config = bzzapi.NewDefaultConfig()
    //first load settings from config file (if provided)
    config, err = configFileOverride(config, ctx)
    if err != nil {
        return nil, err
    }
    //override settings provided by environment variables
    config = envVarsOverride(config)
    //override settings provided by command line
    config = cmdLineOverride(config, ctx)
    //validate configuration parameters
    err = validateConfig(config)

    return
}

//finally, after the configuration build phase is finished, initialize
func initSwarmNode(config *bzzapi.Config, stack *node.Node, ctx *cli.Context) {
    //at this point, all vars should be set in the Config
    //get the account for the provided swarm account
    prvkey := getAccount(config.BzzAccount, ctx, stack)
    //set the resolved config path (geth --datadir)
    config.Path = stack.InstanceDir()
    //finally, initialize the configuration
    config.Init(prvkey)
    //configuration phase completed here
    log.Debug("Starting Swarm with the following parameters:")
    //after having created the config, print it to screen
    log.Debug(printConfig(config))
}

//override the current config with whatever is in the config file, if a config file has been provided
func configFileOverride(config *bzzapi.Config, ctx *cli.Context) (*bzzapi.Config, error) {
    var err error

    //only do something if the -config flag has been set
    if ctx.GlobalIsSet(SwarmTomlConfigPathFlag.Name) {
        var filepath string
        if filepath = ctx.GlobalString(SwarmTomlConfigPathFlag.Name); filepath == "" {
            utils.Fatalf("Config file flag provided with invalid file path")
        }
        f, err := os.Open(filepath)
        if err != nil {
            return nil, err
        }
        defer f.Close()

        //decode the TOML file into a Config struct
        //note that we are decoding into the existing defaultConfig;
        //if an entry is not present in the file, the default entry is kept
        err = tomlSettings.NewDecoder(f).Decode(&config)
        // Add file name to errors that have a line number.
        if _, ok := err.(*toml.LineError); ok {
            err = errors.New(filepath + ", " + err.Error())
        }
    }
    return config, err
}

//override the current config with whatever is provided through the command line
//most values are not allowed a zero value (empty string), if not otherwise noted
func cmdLineOverride(currentConfig *bzzapi.Config, ctx *cli.Context) *bzzapi.Config {

    if keyid := ctx.GlobalString(SwarmAccountFlag.Name); keyid != "" {
        currentConfig.BzzAccount = keyid
    }

    if chbookaddr := ctx.GlobalString(ChequebookAddrFlag.Name); chbookaddr != "" {
        currentConfig.Contract = common.HexToAddress(chbookaddr)
    }

    if networkid := ctx.GlobalString(SwarmNetworkIdFlag.Name); networkid != "" {
        if id, _ := strconv.Atoi(networkid); id != 0 {
            currentConfig.NetworkId = uint64(id)
        }
    }

    if ctx.GlobalIsSet(utils.DataDirFlag.Name) {
        if datadir := ctx.GlobalString(utils.DataDirFlag.Name); datadir != "" {
            currentConfig.Path = datadir
        }
    }

    bzzport := ctx.GlobalString(SwarmPortFlag.Name)
    if len(bzzport) > 0 {
        currentConfig.Port = bzzport
    }

    if bzzaddr := ctx.GlobalString(SwarmListenAddrFlag.Name); bzzaddr != "" {
        currentConfig.ListenAddr = bzzaddr
    }

    if ctx.GlobalIsSet(SwarmSwapEnabledFlag.Name) {
        currentConfig.SwapEnabled = true
    }

    if ctx.GlobalIsSet(SwarmSyncEnabledFlag.Name) {
        currentConfig.SyncEnabled = true
    }

    currentConfig.SwapApi = ctx.GlobalString(SwarmSwapAPIFlag.Name)
    if currentConfig.SwapEnabled && currentConfig.SwapApi == "" {
        utils.Fatalf(SWARM_ERR_SWAP_SET_NO_API)
    }

    if ctx.GlobalIsSet(EnsAPIFlag.Name) {
        ensAPIs := ctx.GlobalStringSlice(EnsAPIFlag.Name)
        // preserve backward compatibility to disable ENS with --ens-api=""
        if len(ensAPIs) == 1 && ensAPIs[0] == "" {
            ensAPIs = nil
        }
        currentConfig.EnsAPIs = ensAPIs
    }

    if ensaddr := ctx.GlobalString(DeprecatedEnsAddrFlag.Name); ensaddr != "" {
        currentConfig.EnsRoot = common.HexToAddress(ensaddr)
    }

    if cors := ctx.GlobalString(CorsStringFlag.Name); cors != "" {
        currentConfig.Cors = cors
    }

    if ctx.GlobalIsSet(utils.BootnodesFlag.Name) {
        currentConfig.BootNodes = ctx.GlobalString(utils.BootnodesFlag.Name)
    }

    return currentConfig

}

//override the current config with whatver is provided in environment variables
//most values are not allowed a zero value (empty string), if not otherwise noted
func envVarsOverride(currentConfig *bzzapi.Config) (config *bzzapi.Config) {

    if keyid := os.Getenv(SWARM_ENV_ACCOUNT); keyid != "" {
        currentConfig.BzzAccount = keyid
    }

    if chbookaddr := os.Getenv(SWARM_ENV_CHEQUEBOOK_ADDR); chbookaddr != "" {
        currentConfig.Contract = common.HexToAddress(chbookaddr)
    }

    if networkid := os.Getenv(SWARM_ENV_NETWORK_ID); networkid != "" {
        if id, _ := strconv.Atoi(networkid); id != 0 {
            currentConfig.NetworkId = uint64(id)
        }
    }

    if datadir := os.Getenv(GETH_ENV_DATADIR); datadir != "" {
        currentConfig.Path = datadir
    }

    bzzport := os.Getenv(SWARM_ENV_PORT)
    if len(bzzport) > 0 {
        currentConfig.Port = bzzport
    }

    if bzzaddr := os.Getenv(SWARM_ENV_LISTEN_ADDR); bzzaddr != "" {
        currentConfig.ListenAddr = bzzaddr
    }

    if swapenable := os.Getenv(SWARM_ENV_SWAP_ENABLE); swapenable != "" {
        if swap, err := strconv.ParseBool(swapenable); err != nil {
            currentConfig.SwapEnabled = swap
        }
    }

    if syncenable := os.Getenv(SWARM_ENV_SYNC_ENABLE); syncenable != "" {
        if sync, err := strconv.ParseBool(syncenable); err != nil {
            currentConfig.SyncEnabled = sync
        }
    }

    if swapapi := os.Getenv(SWARM_ENV_SWAP_API); swapapi != "" {
        currentConfig.SwapApi = swapapi
    }

    if currentConfig.SwapEnabled && currentConfig.SwapApi == "" {
        utils.Fatalf(SWARM_ERR_SWAP_SET_NO_API)
    }

    if ensapi := os.Getenv(SWARM_ENV_ENS_API); ensapi != "" {
        currentConfig.EnsAPIs = strings.Split(ensapi, ",")
    }

    if ensaddr := os.Getenv(SWARM_ENV_ENS_ADDR); ensaddr != "" {
        currentConfig.EnsRoot = common.HexToAddress(ensaddr)
    }

    if cors := os.Getenv(SWARM_ENV_CORS); cors != "" {
        currentConfig.Cors = cors
    }

    if bootnodes := os.Getenv(SWARM_ENV_BOOTNODES); bootnodes != "" {
        currentConfig.BootNodes = bootnodes
    }

    return currentConfig
}

// dumpConfig is the dumpconfig command.
// writes a default config to STDOUT
func dumpConfig(ctx *cli.Context) error {
    cfg, err := buildConfig(ctx)
    if err != nil {
        utils.Fatalf(fmt.Sprintf("Uh oh - dumpconfig triggered an error %v", err))
    }
    comment := ""
    out, err := tomlSettings.Marshal(&cfg)
    if err != nil {
        return err
    }
    io.WriteString(os.Stdout, comment)
    os.Stdout.Write(out)
    return nil
}

//deprecated flags checked here
func checkDeprecated(ctx *cli.Context) {
    // exit if the deprecated --ethapi flag is set
    if ctx.GlobalString(DeprecatedEthAPIFlag.Name) != "" {
        utils.Fatalf("--ethapi is no longer a valid command line flag, please use --ens-api and/or --swap-api.")
    }
    // warn if --ens-api flag is set
    if ctx.GlobalString(DeprecatedEnsAddrFlag.Name) != "" {
        log.Warn("--ens-addr is no longer a valid command line flag, please use --ens-api to specify contract address.")
    }
}

//validate configuration parameters
func validateConfig(cfg *bzzapi.Config) (err error) {
    for _, ensAPI := range cfg.EnsAPIs {
        if ensAPI != "" {
            if err := validateEnsAPIs(ensAPI); err != nil {
                return fmt.Errorf("invalid format [tld:][contract-addr@]url for ENS API endpoint configuration %q: %v", ensAPI, err)
            }
        }
    }
    return nil
}

//validate EnsAPIs configuration parameter
func validateEnsAPIs(s string) (err error) {
    // missing contract address
    if strings.HasPrefix(s, "@") {
        return errors.New("missing contract address")
    }
    // missing url
    if strings.HasSuffix(s, "@") {
        return errors.New("missing url")
    }
    // missing tld
    if strings.HasPrefix(s, ":") {
        return errors.New("missing tld")
    }
    // missing url
    if strings.HasSuffix(s, ":") {
        return errors.New("missing url")
    }
    return nil
}

//print a Config as string
func printConfig(config *bzzapi.Config) string {
    out, err := tomlSettings.Marshal(&config)
    if err != nil {
        return fmt.Sprintf("Something is not right with the configuration: %v", err)
    }
    return string(out)
}