y_flow_list.c File Reference

Business logic / clickflow support. More...

#include "y_core.c"

Go to the source code of this file.

Data Structures
struct	y_flow
	Descriptor for one single flow in a flow list. More...

Typedefs
typedef int(	y_flow_func) ()
	Type definition of a function pointer to the flow to execute. More...

Functions
int	y_calc_flow_weight_total (y_flow flow_list[], int flow_count)
	Calculate the total of the weights in a given flow list. More...
y_flow *	y_choose_flow (y_flow flow_list[], int flow_count)
	Choose a flow from a list of flows. More...
int	y_exec_flow (y_flow *chosen_flow)
	Execute a flow from a flow list. More...
y_flow *	y_get_flow_by_name (char *flow_name, y_flow flow_list[], int flow_count)
	Fetch a specific item from a flow list, by name. More...

Detailed Description

Business logic / clickflow support.

This file implements flow lists. A flow list is is a lists of actions (clickflow) that the script will choose from at random, using a set of predetermined weights. An 'action' is defined as a function that takes no arguments and returns an int - such as an action block, or a function without a specifically defined return type.

Note

The weights can be percentages, hit counts, or whatever you like, as long as the total of the weights does not exceed Y_RAND_MAX.

Example:

int browse()
{
    y_start_transaction("browse");
    web_link("...", LAST);
    y_end_transaction("", LR_AUTO);
}

buy()
{
    y_start_transaction("buy");
    web_link("...", LAST);
    y_end_transaction("", LR_AUTO);
}

// Define other actions as required.

loadtest_flow()
{
    // Define the weights
    static y_flow flow_list[] = {
        { 0, "action block for browsing the site",  browse,          3700 },   // 37.00%
        { 1, "action block for buying a product",   buy,             2100 },   // 21.00%
        { 2, "action block for checking out",       checkout,         200 },   //  2.00%
        { 3, "function for resetting the database", wipe_database,   2500 },   // 25.00%
        { 4, "end the script for no reason",        lr_abort,        1500 } }; // 15.00%
    const int flow_count = (sizeof flow_list / sizeof flow_list[0]); 

    // Choose a flow to execute
    y_flow *chosen_flow = y_choose_flow(flow_list, flow_count);

    // Change the next transaction number to make sure the numbering stays contiguous.
    // (This is optional. You can use that number for whatever you want, this is just a common use for that field.)
    y_set_next_transaction_nr( y_get_next_transaction_nr() + chosen_flow->number);

    // Execute the chosen flow.
    y_exec_flow(chosen_flow);
}

See also

y_choose_flow, y_exec_flow, y_set_next_transaction_nr, y_get_next_transaction_nr.

Author

Floris Kraak

Definition in file y_flow_list.c.

Typedef Documentation

typedef int( y_flow_func) ()

Type definition of a function pointer to the flow to execute.

This matches the prototype for Action() blocks, so you can assign a action blocks to variables of this type.

Definition at line 83 of file y_flow_list.c.

Function Documentation

int y_calc_flow_weight_total	(	y_flow	flow_list[],
		int	flow_count
	)

Calculate the total of the weights in a given flow list.

Given a flowlist of a specified length, calculate the total weight of all flows in a flow list. This is used by other ylib functions. Calling it directly from a script should normally not be needed.

See also

y_flow_list.c, y_choose_flow()

Parameters

[in]	flow_list	An array of y_flow structs, each describing a specific choice in a clickpath.
[in]	flow_count	The number of flows in the list.

Author

Floris Kraak

Definition at line 125 of file y_flow_list.c.

y_flow* y_choose_flow	(	y_flow	flow_list[],
		int	flow_count
	)

Choose a flow from a list of flows.

Parameters

[in]	flow_list	An array of y_flow structs, each describing a specific choice in a clickpath.
[in]	flow_count	The number of flows in the list.

Returns

a pointer to a randomly chosen flow, or NULL if somehow the weights don't add up. (flow list corrupt, flow_count incorrect, etc.)

See also

y_flow_list.c, y_exec_flow()

Note

The flow_count argument should exactly match the number of flows in the array or the script might blow up with MEMORY_ACCESS_VIOLATION errors.

Author

Floris Kraak

Definition at line 147 of file y_flow_list.c.

int y_exec_flow

(

y_flow *

chosen_flow

)

Execute a flow from a flow list.

Usually this is a flow as determined by y_choose_flow().

See also

y_flow_list.c, y_choose_flow()

Parameters

[in]

chosen_flow

The flow to execute.

Returns

the flow's function return value.

Author

Floris Kraak

Definition at line 178 of file y_flow_list.c.

y_flow* y_get_flow_by_name	(	char *	flow_name,
		y_flow	flow_list[],
		int	flow_count
	)

Fetch a specific item from a flow list, by name.

Parameters

[in]	flow_name	The name of the flow to fetch.
[in]	flow_list	The flow list in question.
[in]	flow_count	The number of flows in the list.

Returns

A pointer to the requested flow.

See also

y_flow_list.c, y_choose_flow(), y_exec_flow()

Definition at line 207 of file y_flow_list.c.