soumya92/barista

// Copyright 2018 Google Inc.
//
// 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.

// stable-api demonstrates a bar that exercises barista's stable API.
package main

import (
    "syscall"
    "time"

    "barista.run"
    "barista.run/bar"
    "barista.run/timing"

    "github.com/dustin/go-humanize"
)

type simpleClockModule struct {
    format   string
    interval time.Duration
}

func (s simpleClockModule) Stream(sink bar.Sink) {
    sch := timing.NewScheduler()
    for {
        now := timing.Now()
        sink.Output(bar.TextSegment(now.Format(s.format)))
        next := now.Add(s.interval).Truncate(s.interval)
        sch.At(next).Tick()
    }
}

type diskSpaceModule string

func (d diskSpaceModule) Stream(sink bar.Sink) {
    sch := timing.NewScheduler().Every(5 * time.Second)
    for {
        var stat syscall.Statfs_t
        err := syscall.Statfs(string(d), &stat)
        if sink.Error(err) {
            return
        }
        sink.Output(bar.TextSegment(
            humanize.IBytes(stat.Bavail * uint64(stat.Bsize)),
        ))
        sch.Tick()
    }
}

func main() {
    panic(barista.Run(
        diskSpaceModule("/home"),
        simpleClockModule{"Mon Jan 02", time.Hour},
        simpleClockModule{"15:04:05", time.Second},
    ))
}