process

Documentation

Index

• Variables
• func SetSysProcAttribute(cmd *exec.Cmd)
• type Context
  • func GetContext(ctx context.Context) *Context
  • func (c *Context) GetPID() IDType
  • func (c *Context) GetParent() *Context
  • func (c *Context) Value(key interface{}) interface{}
• type Error
  • func (err *Error) Error() string
  • func (err *Error) Unwrap() error
• type FinishedFunc
• type IDType
  • func GetPID(ctx context.Context) IDType
  • func GetParentPID(ctx context.Context) IDType
• type Manager
  • func GetManager() *Manager
  • func (pm *Manager) Add(parentPID IDType, description string, cancel context.CancelFunc) (IDType, FinishedFunc)
  • func (pm *Manager) AddContext(parent context.Context, description string) (ctx context.Context, cancel context.CancelFunc, finished FinishedFunc)
  • func (pm *Manager) AddContextTimeout(parent context.Context, timeout time.Duration, description string) (ctx context.Context, cancel context.CancelFunc, finshed FinishedFunc)
  • func (pm *Manager) Cancel(pid IDType)
  • func (pm *Manager) Exec(desc, cmdName string, args ...string) (string, string, error)
  • func (pm *Manager) ExecDir(timeout time.Duration, dir, desc, cmdName string, args ...string) (string, string, error)
  • func (pm *Manager) ExecDirEnv(timeout time.Duration, dir, desc string, env []string, cmdName string, ...) (string, string, error)
  • func (pm *Manager) ExecDirEnvStdIn(timeout time.Duration, dir, desc string, env []string, stdIn io.Reader, ...) (string, string, error)
  • func (pm *Manager) ExecTimeout(timeout time.Duration, desc, cmdName string, args ...string) (string, string, error)
  • func (pm *Manager) Processes(onlyRoots bool) []*Process
  • func (pm *Manager) Remove(pid IDType)
• type Process
  • func (p *Process) AddChild(child *Process)
  • func (p *Process) Children() (children []*Process)
  • func (p *Process) RemoveChild(process *Process)

Variables

var (

	// DefaultContext is the default context to run processing commands in
	DefaultContext = context.Background()
)

var ProcessContextKey interface{} = "process-context"

ProcessContextKey is the key under which process contexts are stored

Functions

func SetSysProcAttribute

func SetSysProcAttribute(cmd *exec.Cmd)

SetSysProcAttribute sets the common SysProcAttrs for commands

Types

type Context

type Context struct {
	context.Context
	// contains filtered or unexported fields
}

Context is a wrapper around context.Context and contains the current pid for this context

func GetContext

func GetContext(ctx context.Context) *Context

GetContext will return a process context if one exists

func (*Context) GetPID

func (c *Context) GetPID() IDType

GetPID returns the PID for this context

func (*Context) GetParent

func (c *Context) GetParent() *Context

GetParent returns the parent process context (if any)

func (*Context) Value

func (c *Context) Value(key interface{}) interface{}

Value is part of the interface for context.Context. We mostly defer to the internal context - but we return this in response to the ProcessContextKey

type Error

type Error struct {
	PID         IDType
	Description string
	Err         error
	CtxErr      error
	Stdout      string
	Stderr      string
}

Error is a wrapped error describing the error results of Process Execution

func (*Error) Error

func (err *Error) Error() string

func (*Error) Unwrap

func (err *Error) Unwrap() error

Unwrap implements the unwrappable implicit interface for go1.13 Unwrap()

type FinishedFunc

type FinishedFunc = context.CancelFunc

FinishedFunc is a function that marks that the process is finished and can be removed from the process table - it is simply an alias for context.CancelFunc and is only for documentary purposes

type IDType

type IDType string

IDType is a pid type

func GetPID

func GetPID(ctx context.Context) IDType

GetPID returns the PID for this context

func GetParentPID

func GetParentPID(ctx context.Context) IDType

GetParentPID returns the ParentPID for this context

type Manager

type Manager struct {
	// contains filtered or unexported fields
}

Manager manages all processes and counts PIDs.

func GetManager

func GetManager() *Manager

GetManager returns a Manager and initializes one as singleton if there's none yet

func (*Manager) Add

func (pm *Manager) Add(parentPID IDType, description string, cancel context.CancelFunc) (IDType, FinishedFunc)

Add create a new process

func (*Manager) AddContext

func (pm *Manager) AddContext(parent context.Context, description string) (ctx context.Context, cancel context.CancelFunc, finished FinishedFunc)

AddContext creates a new context and adds it as a process. Once the process is finished, finished must be called to remove the process from the process table. It should not be called until the process is finished but must always be called.

cancel should be used to cancel the returned context, however it will not remove the process from the process table. finished will cancel the returned context and remove it from the process table.

Most processes will not need to use the cancel function but there will be cases whereby you want to cancel the process but not immediately remove it from the process table.

func (*Manager) AddContextTimeout

func (pm *Manager) AddContextTimeout(parent context.Context, timeout time.Duration, description string) (ctx context.Context, cancel context.CancelFunc, finshed FinishedFunc)

AddContextTimeout creates a new context and add it as a process. Once the process is finished, finished must be called to remove the process from the process table. It should not be called until the process is finished but must always be called.

cancel should be used to cancel the returned context, however it will not remove the process from the process table. finished will cancel the returned context and remove it from the process table.

Most processes will not need to use the cancel function but there will be cases whereby you want to cancel the process but not immediately remove it from the process table.

func (*Manager) Cancel

func (pm *Manager) Cancel(pid IDType)

Cancel a process in the ProcessManager.

func (*Manager) Exec

func (pm *Manager) Exec(desc, cmdName string, args ...string) (string, string, error)

Exec a command and use the default timeout.

func (*Manager) ExecDir

func (pm *Manager) ExecDir(timeout time.Duration, dir, desc, cmdName string, args ...string) (string, string, error)

ExecDir a command and use the default timeout.

func (*Manager) ExecDirEnv

func (pm *Manager) ExecDirEnv(timeout time.Duration, dir, desc string, env []string, cmdName string, args ...string) (string, string, error)

ExecDirEnv runs a command in given path and environment variables, and waits for its completion up to the given timeout (or DefaultTimeout if -1 is given). Returns its complete stdout and stderr outputs and an error, if any (including timeout)

func (*Manager) ExecDirEnvStdIn

func (pm *Manager) ExecDirEnvStdIn(timeout time.Duration, dir, desc string, env []string, stdIn io.Reader, cmdName string, args ...string) (string, string, error)

ExecDirEnvStdIn runs a command in given path and environment variables with provided stdIN, and waits for its completion up to the given timeout (or DefaultTimeout if -1 is given). Returns its complete stdout and stderr outputs and an error, if any (including timeout)

func (*Manager) ExecTimeout

func (pm *Manager) ExecTimeout(timeout time.Duration, desc, cmdName string, args ...string) (string, string, error)

ExecTimeout a command and use a specific timeout duration.

func (*Manager) Processes

func (pm *Manager) Processes(onlyRoots bool) []*Process

Processes gets the processes in a thread safe manner

func (*Manager) Remove

func (pm *Manager) Remove(pid IDType)

Remove a process from the ProcessManager.

type Process

type Process struct {
	PID         IDType // Process ID, not system one.
	ParentPID   IDType
	Description string
	Start       time.Time
	Cancel      context.CancelFunc
	// contains filtered or unexported fields
}

Process represents a working process inheriting from Gitea.

func (*Process) AddChild

func (p *Process) AddChild(child *Process)

AddChild adds a child process Note: this function will behave nicely even if p is nil

func (*Process) Children

func (p *Process) Children() (children []*Process)

Children gets the children of the process Note: this function will behave nicely even if p is nil

func (*Process) RemoveChild

func (p *Process) RemoveChild(process *Process)

RemoveChild removes a child process Note: this function will behave nicely even if p is nil