Beesnest/Engines/BnPython/BnPython.h

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/* DcDynamicHTML.h: interface for the CdcDynamicHTML class. */

#ifndef __CDC_DAYNAMIC_HTML
#define __CDC_DAYNAMIC_HTML

#include <Python.h>

#include "../../Interfaces/DcEngine.h"

#include <iostream>
#include <map>
#include <set>
using namespace std;

#include <time.h>

/**
 * This is a wrapper to the Python interpreter, for the Beesnest server.<br>
 * The only issue here is that the Python interpreter works with "C" style
 * functions, but Beesnest works with classes and objects. The solution: in
 * every call to a Beesnest function from python, "self" will be an integer that
 * will map to one of this class instances. The user doesn't have to do anything
 * for it.
 *
 * 2008-01-18 - I overload the "exit" function. It will terminate the script
 * but return True (so it will not consider as an error). However, I use
 * Python exception to do it.
 * Calling sys.exit terminate the entire Beesnest application. This is a bug!
 */
class BnPython : public IdcEngine
{
private:
    /** Pointer to the response object. */
    IdcResponse* pRes;

    /** Pointer to the request object. */
    IdcRequest* pReq;

    /** Optional pointer to the adapters set object. */
    IdcAdaptersSet* pSet;

    /** Set to store all (unreleased) adapters. */
    set<unsigned int> oAdaptersList;

    /** Pointer to a function of Beesnest to get parameters from
        the configuration files. */
    bool (*pfGetParam)(const char*, char*, int);

    /** Store the name of this engine object. */
    string sName;

    /** Pointer to the Python interpreter thread. */
    PyThreadState* oTS;

    /** The buffer to return to Beesnest. */
    string sBuffer;

    /** This is the key to the pointer of the class instance. */
    int nPointerCell;

    /** This is the returned buffer size limit. */
    int nSizeLimit;

    /** Non zero if need to throw exception to Beesnest. */
    int nException;

    /** Will be false if script terminate using "exit" - no error message. */
    bool bExit;
    // Note that sys.exit will close Beesnest - This is a bug.

    /** Counter to get next key. */
    static int counter;

    /** This static map store pointers to the class instances. */
    static map<int, BnPython*> mPointers;

    /** This static function return a pointer to BnPython instance by an integer
        key, or NULL if key is invalid. */
    static BnPython* GetPointer (int num);

    /** This function releases all the adapters when script is done. */
    void ReleaseAdapters ();

    /** This function checks that the returned buffer is still in the size limit. */
    bool CheckSizeLimit ();

public:
    /**
     * Constractor - Starts the interpreter and initialize variables. It also
     * inserts the pointer to this object (this) to the Pointers map, under a
     * new integer key.
     */
    BnPython (const char* name, bool (*pGetParam)(const char*, char*, int));

    /**
     * Destructor - Close the interpreter.
     */
    virtual ~BnPython ();

    /**
     * Do the actual processing of a script.
     */
    virtual bool Process (BufferHolder code, BufferHolder& result, int size_limit);

    /**
     * Prepare the class for a new request. Set the new Request, Response and
     * maybe Adapters Set objects.
     */
    virtual void Prepare (IdcRequest* preq, IdcResponse* pres, IdcAdaptersSet* pset);

    /**
     * Just return True in most cases. Return False after an exception.
     */
    virtual bool IsStorable () { return nException == 0; }

    /**
     * Make sure all the adapters are released, and clear the buffer that goes
     * back to Beesnest.
     */
     virtual void Stored ();

    /* "C" style functions to transfer to the Python interpreter.
        They all look the same. */

    friend PyObject* Print (PyObject *self, PyObject *args);
    friend PyObject* GetRequestHeader (PyObject *self, PyObject *args);
    friend PyObject* GetRequestVariable (PyObject *self, PyObject *args);
    friend PyObject* SetRequestVariable (PyObject *self, PyObject *args);
    friend PyObject* GetRequestVarsNamesList (PyObject *self, PyObject *args);
    friend PyObject* SetResponseHeader (PyObject *self, PyObject *args);
    friend PyObject* SetResponseCookie (PyObject *self, PyObject *args);
    friend PyObject* Clear (PyObject *self, PyObject *args);
    friend PyObject* Flush (PyObject *self, PyObject *args);
    friend PyObject* GetAdapter (PyObject *self, PyObject *args);
    friend PyObject* ReleaseAdapter (PyObject *self, PyObject *args);
    friend PyObject* Read (PyObject *self, PyObject *args);
    friend PyObject* Write (PyObject *self, PyObject *args);
    friend PyObject* Exit (PyObject *self, PyObject *args);
};

#endif /* __CDC_DAYNAMIC_HTML */