wings/environment/settings.go

132 lines
4.5 KiB
Go

package environment
import (
"fmt"
"github.com/apex/log"
"math"
"strconv"
)
type Mount struct {
// In Docker environments this makes no difference, however in a non-Docker environment you
// should treat the "Default" mount as the root directory for the server. All other mounts
// are just in addition to that one, and generally things like shared maps or timezone data.
Default bool `json:"-"`
// The target path on the system. This is "/home/container" for all server's Default mount
// but in non-container environments you can likely ignore the target and just work with the
// source.
Target string `json:"target"`
// The directory from which the files will be read. In Docker environments this is the directory
// that we're mounting into the container at the Target location.
Source string `json:"source"`
// Wether or not the directory is being mounted as read-only. It is up to the environment to
// handle this value correctly and ensure security expectations are met with its usage.
ReadOnly bool `json:"read_only"`
}
// The build settings for a given server that impact docker container creation and
// resource limits for a server instance.
type Limits struct {
// The total amount of memory in megabytes that this server is allowed to
// use on the host system.
MemoryLimit int64 `json:"memory_limit"`
// The amount of additional swap space to be provided to a container instance.
Swap int64 `json:"swap"`
// The relative weight for IO operations in a container. This is relative to other
// containers on the system and should be a value between 10 and 1000.
IoWeight uint16 `json:"io_weight"`
// The percentage of CPU that this instance is allowed to consume relative to
// the host. A value of 200% represents complete utilization of two cores. This
// should be a value between 1 and THREAD_COUNT * 100.
CpuLimit int64 `json:"cpu_limit"`
// The amount of disk space in megabytes that a server is allowed to use.
DiskSpace int64 `json:"disk_space"`
// Sets which CPU threads can be used by the docker instance.
Threads string `json:"threads"`
OOMDisabled bool `json:"oom_disabled"`
}
// Converts the CPU limit for a server build into a number that can be better understood
// by the Docker environment. If there is no limit set, return -1 which will indicate to
// Docker that it has unlimited CPU quota.
func (r *Limits) ConvertedCpuLimit() int64 {
if r.CpuLimit == 0 {
return -1
}
return r.CpuLimit * 1000
}
// Set the hard limit for memory usage to be 5% more than the amount of memory assigned to
// the server. If the memory limit for the server is < 4G, use 10%, if less than 2G use
// 15%. This avoids unexpected crashes from processes like Java which run over the limit.
func (r *Limits) MemoryOverheadMultiplier() float64 {
if r.MemoryLimit <= 2048 {
return 1.15
} else if r.MemoryLimit <= 4096 {
return 1.10
}
return 1.05
}
func (r *Limits) BoundedMemoryLimit() int64 {
return int64(math.Round(float64(r.MemoryLimit) * r.MemoryOverheadMultiplier() * 1_000_000))
}
// Returns the amount of swap available as a total in bytes. This is returned as the amount
// of memory available to the server initially, PLUS the amount of additional swap to include
// which is the format used by Docker.
func (r *Limits) ConvertedSwap() int64 {
if r.Swap < 0 {
return -1
}
return (r.Swap * 1_000_000) + r.BoundedMemoryLimit()
}
type Variables map[string]interface{}
// Ugly hacky function to handle environment variables that get passed through as not-a-string
// from the Panel. Ideally we'd just say only pass strings, but that is a fragile idea and if a
// string wasn't passed through you'd cause a crash or the server to become unavailable. For now
// try to handle the most likely values from the JSON and hope for the best.
func (v Variables) Get(key string) string {
val, ok := v[key]
if !ok {
return ""
}
switch val.(type) {
case int:
return strconv.Itoa(val.(int))
case int32:
return strconv.FormatInt(val.(int64), 10)
case int64:
return strconv.FormatInt(val.(int64), 10)
case float32:
return fmt.Sprintf("%f", val.(float32))
case float64:
return fmt.Sprintf("%f", val.(float64))
case bool:
return strconv.FormatBool(val.(bool))
case string:
return val.(string)
}
// TODO: I think we can add a check for val == nil and return an empty string for those
// and this warning should theoretically never happen?
log.Warn(fmt.Sprintf("failed to marshal environment variable \"%s\" of type %+v into string", key, val))
return ""
}