featurebase/cmd/server.go
Seebs 3c05f1ff37 Distinguish between usage errors and other errors
Cobra automatically displays usage messages, and also a gratuitous
"Error: [...]" line in some cases, when any error at all occurs
running a command. To suppress the usage message, you have to set
cmd.SilenceUsage to true. But the code that would do this doesn't
have access to it. To address this, we introduce a category of
"usage error", implemented with stdlib error wrapping (%w) and
use errors.Is to check for it. There's also utility functions
to do this checking automatically, or indeed, to handle wrapping
of the ctl.SomethingCommand and handle running it with a suitable
context and everything.

In fact, several of the places we're checking for usage errors,
we can never actually report one, but we're checking consistently
so that if we want to report usage errors, we can.

For instance, server.Start and (dax)server.Start don't ever
return usage errors, right now, but we're checking their responses
anyway.

(cherry picked from commit c681642734)
2022-12-12 09:01:20 -08:00

125 lines
3.9 KiB
Go

// Copyright 2022 Molecula Corp. (DBA FeatureBase).
// SPDX-License-Identifier: Apache-2.0
package cmd
import (
"io"
"github.com/featurebasedb/featurebase/v3/ctl"
"github.com/featurebasedb/featurebase/v3/server"
"github.com/featurebasedb/featurebase/v3/tracing"
"github.com/featurebasedb/featurebase/v3/tracing/opentracing"
"github.com/pkg/errors"
"github.com/spf13/cobra"
jaegercfg "github.com/uber/jaeger-client-go/config"
"gopkg.in/DataDog/dd-trace-go.v1/profiler"
)
// Server is global so that tests can control and verify it.
var Server *server.Command
var holder *server.Command
// newHolderCmd creates a FeatureBase server for just long enough to open the
// holder, then shuts it down again.
func newHolderCmd(stdin io.Reader, stdout, stderr io.Writer) *cobra.Command {
holder = server.NewCommand(stdin, stdout, stderr)
serveCmd := &cobra.Command{
Use: "holder",
Short: "Load FeatureBase.",
Long: `featurebase holder starts (and immediately stops) FeatureBase.
It opens the data directory and loads it, then shuts down immediately.
This is only useful for diagnostic use.
`,
RunE: func(cmd *cobra.Command, args []string) error {
// Start & run the server.
if err := holder.UpAndDown(); err != nil {
return errors.Wrap(err, "running server")
}
return nil
},
}
// Attach flags to the command.
ctl.BuildServerFlags(serveCmd, holder)
return serveCmd
}
// newServeCmd creates a FeatureBase server and runs it with command line flags.
func newServeCmd(stdin io.Reader, stdout, stderr io.Writer) *cobra.Command {
Server = server.NewCommand(stdin, stdout, stderr)
serveCmd := &cobra.Command{
Use: "server",
Short: "Run FeatureBase.",
Long: `featurebase server runs FeatureBase.
It will load existing data from the configured
directory and start listening for client connections
on the configured port.`,
RunE: func(cmd *cobra.Command, args []string) error {
// Start & run the server.
if err := Server.Start(); err != nil {
return considerUsageError(cmd, errors.Wrap(err, "running server"))
}
// anything past here is definitely not a usage error
cmd.SilenceErrors = true
cmd.SilenceUsage = true
if Server.Config.DataDog.Enable {
opts := make([]profiler.ProfileType, 0)
if Server.Config.DataDog.CPUProfile {
opts = append(opts, profiler.CPUProfile)
}
if Server.Config.DataDog.HeapProfile {
opts = append(opts, profiler.HeapProfile)
}
if Server.Config.DataDog.BlockProfile {
opts = append(opts, profiler.BlockProfile)
}
if Server.Config.DataDog.GoroutineProfile {
opts = append(opts, profiler.GoroutineProfile)
}
if Server.Config.DataDog.MutexProfile {
opts = append(opts, profiler.MutexProfile)
}
err := profiler.Start(
profiler.WithService(Server.Config.DataDog.Service),
profiler.WithEnv(Server.Config.DataDog.Env),
profiler.WithVersion(Server.Config.DataDog.Version),
profiler.WithTags(Server.Config.DataDog.Tags),
profiler.WithProfileTypes(
opts...,
),
)
if err != nil {
return errors.Wrap(err, "starting datadog")
}
defer profiler.Stop()
}
if Server.Config.Tracing.SamplerType != "off" {
// Initialize tracing in the command since it is global.
var cfg jaegercfg.Configuration
cfg.ServiceName = "pilosa"
cfg.Sampler = &jaegercfg.SamplerConfig{
Type: Server.Config.Tracing.SamplerType,
Param: Server.Config.Tracing.SamplerParam,
}
cfg.Reporter = &jaegercfg.ReporterConfig{
LocalAgentHostPort: Server.Config.Tracing.AgentHostPort,
}
tracer, closer, err := cfg.NewTracer()
if err != nil {
return errors.Wrap(err, "initializing jaeger tracer")
}
defer closer.Close()
tracing.GlobalTracer = opentracing.NewTracer(tracer, Server.Logger())
}
return errors.Wrap(Server.Wait(), "waiting on Server")
},
}
// Attach flags to the command.
ctl.BuildServerFlags(serveCmd, Server)
return serveCmd
}