class ProcessLauncherInterface

Overview

Functions for all process launchers. More…

#include <process_launcher.h>

class ProcessLauncherInterface: public PtrTemplates {
public:
    // typedefs

    typedef LaunchCommandInterface::ENGINE_RUNNING_STATUS ENGINE_RUNNING_STATUS;

    // fields

    static constexpr auto UNKNOWN = LaunchCommandInterface::ENGINE_RUNNING_STATUS::UNKNOWN;
    static constexpr auto RUNNING = LaunchCommandInterface::ENGINE_RUNNING_STATUS::RUNNING;
    static constexpr auto STOPPED = LaunchCommandInterface::ENGINE_RUNNING_STATUS::STOPPED;

    // methods

    virtual std::string launcherName() const = 0;
    virtual ProcessLauncherInterface::unique_ptr createLauncher(int logFD = -1) = 0;

    virtual pid_t launchProcess(
        nlohmann::json procConfig,
        bool appendParentEnv = true
    ) = 0;

    virtual pid_t stopProcess(unsigned int killWait) = 0;
    virtual ENGINE_RUNNING_STATUS getProcessStatus();
    LaunchCommandInterface* launchCommand() const;
    void setFileDescriptor(int logFD);
};

// direct descendants

template <
    class PROCESS_LAUNCHER,
    const char* LAUNCHER_TYPE,
    class ... LAUNCHER_COMMANDS
>
class ProcessLauncher;

Inherited Members

public:
    // typedefs

    typedef std::shared_ptr<T> shared_ptr;
    typedef std::shared_ptr<const T> const_shared_ptr;
    typedef std::unique_ptr<T> unique_ptr;
    typedef std::unique_ptr<const T> const_unique_ptr;

Detailed Documentation

Functions for all process launchers.

Methods

virtual std::string launcherName() const = 0

Get name of launcher.

virtual ProcessLauncherInterface::unique_ptr createLauncher(int logFD = -1) = 0

Create a new process launcher.

Parameters:

logFD

File descriptor to route stdout and stderror outputs in launched process

virtual pid_t launchProcess(
    nlohmann::json procConfig,
    bool appendParentEnv = true
) = 0

Fork a new process. Will read environment variables and start params from procConfig.

Parameters:

procConfig	Process Configuration. Env variables and start params take precedence over envParams and startParams
appendParentEnv	Should parent env variables be appended to child process

Returns:

Returns Process ID of child process on success

virtual pid_t stopProcess(unsigned int killWait) = 0

Stop a running process.

Parameters:

killWait

Time (in seconds) to wait for process to quit by itself before force killing it. 0 means it will wait indefinitely

Returns:

Returns child PID on success, negative value on error

virtual ENGINE_RUNNING_STATUS getProcessStatus()

Get the current process status. If status cannot be retrieved, return ENGINE_RUNNING_STATUS::UNKNOWN.

Returns:

Returns status as enum ProcessLauncherInterface::ENGINE_RUNNING_STATUS

LaunchCommandInterface* launchCommand() const

Get Launch Command. If launchProcess has not yet been called, return nullptr.

void setFileDescriptor(int logFD)

Sets the file descriptor that will be used by the launched process to write stdout and stderror.

Parameters:

logFD

File descriptor to route stdout and stderror outputs in launched process