Patent Publication Number: US-9852048-B2

Title: Simulating process variable changes during process runtime

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates generally to the field of software debugging, and more particularly to simulating process variable changes during process runtime for debugging. 
     In an electronic workflow management system, a workflow can be defined as a sequence of concatenated steps to carry out predefined tasks or activities. A workflow can depict a sequence of electronic operations. A typical workflow management system has two components: a design component and a runtime component. The design component typically allows a user to define a process using elements, such as nodes. The runtime component is often responsible for processing data according to one or more workflow processes defined by an end user, using the design components. Often, a workflow engine needs to track and monitor the change in data. 
     It is common for both a customer and a support team to reproduce problems in another environment for debugging, which may be caused by variable changes. Variables may include both global variables and local variables, and variables can be changed by a service, an output of an event, by a script, and/or by an API. 
     SUMMARY 
     According to an embodiment of the present invention, a method, computer program product, and computer system for simulating variable changes are provided. The method comprises: during runtime of a process, recording, by one or more processors, a set of variable changes and a process context; filtering, by one or more processors, sensitive content from the set of variable changes and the process context; importing, by one or more processors, the recorded set of variable changes into a simulator; and executing, by one or more processors, the simulator, to simulate a running sequence of the process using the recorded set of variable changes and the process context. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts a block diagram illustrating a processing environment, in accordance with an embodiment of the present invention; 
         FIG. 2A  depicts a flowchart illustrating operational steps for inspecting and recording process variable changes during process runtime, in accordance with an embodiment of the present invention; 
         FIG. 2B  depicts a flowchart illustrating operational steps for using a process variable inspector to record process variable changes and to process context, in accordance with an embodiment of the present invention; 
         FIG. 2C  depicts a flowchart illustrating operational steps for invoking a process engine simulator to simulate a process running sequence, in accordance with an embodiment of the present invention; 
         FIG. 3  depicts an example customer environment of a process error caused by variables, in accordance with an embodiment of the present invention; 
         FIG. 4  depicts an example environment in which a process variable inspector maps variable points to code snippets, in accordance with an embodiment of the present invention; 
         FIG. 5A  depicts an example environment in which a process variable inspector records variable points by a timeline, in accordance with an embodiment of the present invention; 
         FIGS. 5B and 5C  depict example tables of process variable change data structures and variable value data structures, respectively, of the variable changes in  FIG. 5A , in accordance with an embodiment of the present invention; 
         FIG. 6  depicts an example environment in which sensitive content is filtered, in accordance with an embodiment of the present invention; 
         FIG. 7  depicts an example simulation process running sequence for parallel processing nodes, in accordance with an embodiment of the present invention; and 
         FIG. 8  depicts a block diagram of components of a computing device, in accordance with an illustrative embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of the present invention provide systems and methods for inspecting process variable changes during process runtime in a customer environment, in order to help a user effectively check a process problem (e.g., a bug) by reproducing the process instance containing the problem in a simulation environment. 
     The present invention will now be described in detail with reference to the Figures.  FIG. 1  depicts a block diagram illustrating a processing environment, generally designated  100 , in accordance with an embodiment of the present invention. Modifications to processing environment  100  may be made by those skilled in the art without departing from the scope of the invention as recited by the claims. In an exemplary embodiment, processing environment  100  includes customer environment  110  and simulation environment  140 . 
     In this exemplary embodiment, customer environment  110  includes process administrator  102 , process engine  112 , process variable changes  120 , and process context  130 . Process engine  112  includes process instance  114 , process variable inspector  116 , and process content filter  118 . 
     Process instance  114  is the current process instance running in process engine  112 . Process variable inspector  116  inspects process variable changes during process runtime. Process content filter  118  can be used by process administrator  102  to filter sensitive content from process variable changes  120  and process context  130 . Process variable changes  120  record the process variable changes during process runtime, and process context  130  records the input and output of each processing node. 
     Simulation environment  140  includes user  104 , process engine simulator  142 , process variable import tool  150 , and process engine debugger  160 . In this exemplary embodiment, user  104  can be a process developer, process engine tester, process engine developer, or any other type of user which can import process variable changes  120  into process engine simulator  142 , in order to reproduce a problem (e.g., a bug). User  104  can use process variable import tool  150  to import process variable changes  120  into process engine simulator  142 , which then simulates the imported process instance. Process engine debugger  160  can communicate with process engine simulator  142  to debug the imported process instance in a step-by-step manner. 
       FIG. 2A  depicts a flowchart illustrating operational steps for inspecting and recording process variable changes  120  during process runtime, in accordance with an embodiment of the present invention. 
     In step  202 , process administrator  102  finds a process error which is caused by a variable. In this exemplary embodiment, after analyzing the process error according to business logic, process administrator  102  may determine that the error is caused by the wrong variable value. In some embodiments, the analysis of the process error is performed by a human. An example of a process error caused by a variable is further depicted in  FIG. 3 . 
     In step  204 , process administrator  102  uses process variable inspector  116  to record process variable changes  120  and process context  130 . In an embodiment, process administrator  102  invokes the operational steps of  FIG. 2B  for using process variable inspector  116  to record variable changes  120  and process context  130  (described in further detail below). 
     In step  206 , process administrator  102  uses process content filter  118  to filter sensitive content. For example, personal information or other sensitive content may be filtered from process variables by process content filter  118 . This is further depicted with respect to  FIG. 6 . 
     In step  208 , user  104  uses process variable import tool  150  to import process variable changes  120  into process engine simulator  142 , in order to check a problem. 
     In step  210 , user  104  invokes process engine simulator  142  to simulate the process running sequence using process variable changes  120  and process context  130 . In an embodiment, user  104  invokes the process running sequence of  FIG. 2C  (discussed below) to simulate the process running sequence using process variable changes  120  and process context  130 . 
       FIG. 2B  depicts a flowchart illustrating operational steps for using a process variable inspector  116  to record process variable changes  120  and to process context  130 , in accordance with an embodiment of the present invention. 
     In step  220 , process administrator  102  inputs variable information into process variable inspector  116 . The variable information may include the variable name and the variable type (e.g., global or local). 
     In step  222 , process variable inspector  116  searches the read and write variable points in the process template, and adds tags to the searched read and write variable points. 
     In step  224 , process administrator  102  reruns the process. In this exemplary embodiment, the process is rerun in order to record variable changes (i.e., each tagged read and write variable point) and to process context. 
     In step  226 , process variable inspector  116  records process context  130  after the process is rerun. 
     In step  228 , process variable inspector  116  records variable changes  120  after the process is rerun. 
     In step  230 , the subroutine returns to step  206  of  FIG. 2A . 
       FIG. 2C  depicts a flowchart illustrating operational steps for invoking a process engine simulator  142  to simulate a process running sequence, in accordance with an embodiment of the present invention. 
     In step  240 , process engine simulator  142  receives process variable changes  120  from user  104 . 
     In step  242 , process engine simulator  142  sets breakpoints on the process. In this exemplary embodiment, the breakpoints are set according to the received variable changes at each tagged read and write variable point. 
     In step  244 , process engine simulator  142  starts a process instance for debugging. In some embodiments, variable changes and process context can be inspected in the customer environment  110 , which can be used for static analysis, without simulating in process engine debugger  160 . 
     In step  246 , process engine simulator  142  determines whether a process instance stops at the breakpoint. 
     If, in step  246 , process engine simulator  142  determines that the process instance stops at the breakpoint, then, in step  248 , process engine simulator  142  sends a continue signal to process engine debugger  160 , according to the process variable change sequence. 
     If, in step  246 , process engine simulator  142  determines that the process instance does not stop at the breakpoint, then the operational steps end. 
       FIG. 3  depicts an example customer environment of a process error caused by variables, in accordance with an embodiment of the present invention. 
     As depicted in  FIG. 3 , the customer environment includes a process instance  114 , which includes nodes  302 A-G. Node  302 E includes subprocess  304 , with nodes  306 A-C, and node  306 A includes subprocess  308  with nodes  310 A-B. In this example, the process fails at node  304 F, which may be caused by an error in the read and write variable sequence of nodes  302 C-E (i.e., the three previous process nodes to node  302 F). 
       FIG. 4  depicts an example environment in which a process variable inspector  116  maps variable points to code snippets, in accordance with an embodiment of the present invention. 
     As depicted in  FIG. 4 , process variable inspector  116  maps the read and write variable points to code snippets, after recording the variable changes (i.e., each tagged read and write variable point, where the tagged read variables are marked with white plus signs and the tagged write variables are marked with shaded plus signs). Process variable changes  120  include main process  402  and variable value  404 . At an example tagged read point  410 A, process variable inspector  116  records the read variable code snippet  406 , which reads in a variable and the corresponding variable value, and at an example tagged write point  410 B, process variable inspector  116  records the write variable code snippet  408 , which writes a value for the variable change and the corresponding variable value. 
       FIG. 5A  depicts an example environment in which a process variable inspector  116  records variable points by a timeline, in accordance with an embodiment of the present invention. 
     The process may read or update a variable at any point, and each change in variable value for the variables is recorded when the process executes. The variable changes trigger a recorder to record the timeline of variables changing, and all recorded variable changes are then constructed into the timeline for each of the variables, e.g., when and which code snippet changes the variable, the value of the variables, etc. The recorded timeline can be used for static analysis, and playback at a later point in time, in the simulation environment  140 . 
     In this exemplary embodiment, all process variable changes  120  recorded to code snippets (i.e., read variable code snippet  406  and write variable code snippet  408  of  FIG. 4 ) are constructed as a timeline for the variables, for example, at which point in time and which code changed the variable, the variable values, etc. For example, each variable change is marked with an identification, p1-p8, which denotes the point in time the process variable change is recorded (e.g., identification p1 recorded first, then identification p2, etc.). The recorded timeline can be used for static analysis and playback in process engine debugger  160  at a later time. As depicted in  FIG. 5A , read and write variable changes, including the main process  502  and variable value  504 , are recorded for the main process  502 , and its subprocesses. 
       FIGS. 5B and 5C  depict example tables of process variable change data structures and variable value data structures, respectively, of the variable changes in  FIG. 5A , in accordance with an embodiment of the present invention. 
     As depicted in  FIGS. 5B and 5C , process variable changes and variable values are recorded in a table format, to accompany the recorded read and write variables points of  FIG. 5A . In  FIG. 5B , each process variable change identification (i.e., p1-p8) is recorded, along with relevant data associated with the process variable change. For example, the identification p1 is associated with a name  532  (e.g., Main.A.va), a timestamp  534  (e.g., 2015-06-26T09:56:50.150), a process  536  (e.g., Main), a process node  538  (e.g., A), a type  540  (e.g., Write), a variable type  542  (e.g., Global), and a code snippet  544 . 
       FIG. 5C  displays the recorded variable values in a table format. For example, between the start point  554  and end point  556  of identification p1 in  FIG. 5A , the variable value  552  (variable value  504  in  FIG. 5A ) is null, and between the start point  554  of identification p1 and end point  556  of identification p5 of  FIG. 5A , the variable value  552  (variable value  504  in  FIG. 5A ) is 0. 
       FIG. 6  depicts an example environment in which sensitive content is filtered, in accordance with an embodiment of the present invention. 
     As depicted in the example of  FIG. 6 , process content filter  118  takes the initial variable content  602  and filters the sensitive content from process variable changes  120  and process context  130 . For example, sensitive information could include the address, phone number, and personal identification number of a user. Process content filter  118  can identify this personal information, and filter out the personal information to updated variable content  604 , so as not to show up in later processing stages. 
       FIG. 7  depicts an example simulation process running sequence for parallel processing nodes, in accordance with an embodiment of the present invention. 
     Process engine simulator  142  communicates with process engine debugger  160 , using the set breakpoints, based on the process variable changes to simulate the same process variable change sequence as the runtime process. Process engine simulator  142  controls process engine debugger  160  by instructing process engine debugger  160  where to set the breakpoints, what context and variable values to set, and which breakpoints in parallel paths should be executed first. For example, as depicted in  FIG. 7 , there are several breakpoints  802 A-F (p3-p8, respectively), which are set based on process variable changes. When process engine simulator  142  starts to simulate the process (i.e., step  210  of  FIG. 2A ), it sends a “start” command to process engine debugger  160  (i.e., step  244  of  FIG. 2C ). Process engine debugger  160  then stops at breakpoints  802 A (p3),  802 B (p4), and  802 C (p5), and returns the values recorded at the breakpoints to process engine simulator  142 . Process engine simulator  142  chooses the headmost breakpoint ( 802 A in this example) in the breakpoints that process engine debugger  160  returned, and sends a “continue breakpoint  802 A (p3)” command to process engine debugger  160 , to continue to simulate the process (i.e., step  248  of  FIG. 2C ). Process engine simulator  142  and process engine debugger  160  continue to communicate with each other in this manner, until the last breakpoints are hit (p8 in this example), and then ends the communication. 
       FIG. 8  depicts a block diagram of internal and external components of a computing device, generally designated  800 , which is representative of components of  FIG. 1 , in accordance with an embodiment of the present invention. It should be appreciated that  FIG. 8  provides only an illustration of one implementation and does not imply any limitations with regard to the environments in which different embodiments may be implemented. Many modifications to the depicted environment may be made. 
     Computing device  800  includes communications fabric  802 , which provides communications between computer processor(s)  804 , memory  806 , cache  816 , persistent storage  808 , communications unit  810 , and input/output (I/O) interface(s)  812 . Communications fabric  802  can be implemented with any architecture designed for passing data and/or control information between processors (such as microprocessors, communications and network processors, etc.), system memory, peripheral devices, and any other hardware components within a system. For example, communications fabric  802  can be implemented with one or more buses. 
     Memory  806  and persistent storage  808  are computer-readable storage media. In this embodiment, memory  806  includes random access memory (RAM). In general, memory  806  can include any suitable volatile or non-volatile computer readable storage media. Cache  816  is a fast memory that enhances the performance of processors  804  by holding recently accessed data, and data near recently accessed data, from memory  806 . 
     Program instructions and data used to practice embodiments of the present invention may be stored in persistent storage  808  and in memory  806  for execution by one or more of the respective processors  804  via cache  816 . In an embodiment, persistent storage  808  includes a magnetic hard disk drive. Alternatively, or in addition to a magnetic hard disk drive, persistent storage  808  can include a solid state hard drive, a semiconductor storage device, read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, or any other computer readable storage media that is capable of storing program instructions or digital information. 
     The media used by persistent storage  808  may also be removable. For example, a removable hard drive may be used for persistent storage  808 . Other examples include optical and magnetic disks, thumb drives, and smart cards that are inserted into a drive for transfer onto another computer readable storage medium that is also part of persistent storage  808 . 
     Communications unit  810 , in these examples, provides for communications with other data processing systems or devices, including resources of a network. In these examples, communications unit  810  includes one or more network interface cards. Communications unit  810  may provide communications through the use of either or both physical and wireless communications links. Program instructions and data used to practice embodiments of the present invention may be downloaded to persistent storage  808  through communications unit  810 . 
     I/O interface(s)  812  allows for input and output of data with other devices that may be connected to computing device  800 . For example, I/O interface  812  may provide a connection to external devices  818  such as a keyboard, keypad, a touch screen, and/or some other suitable input device. External devices  818  can also include portable computer-readable storage media such as, for example, thumb drives, portable optical or magnetic disks, and memory cards. Software and data used to practice embodiments of the present invention (e.g., software and data) can be stored on such portable computer-readable storage media and can be loaded onto persistent storage  808  via I/O interface(s)  812 . I/O interface(s)  812  also connect to a display  820 . 
     Display  820  provides a mechanism to display data to a user and may be, for example, a computer monitor, or a television screen. 
     The present invention may be a system, a method, and/or a computer program product. The computer program product may include a computer readable storage medium (or media) having computer readable program instructions thereon for causing a processor to carry out aspects of the present invention. 
     The computer readable storage medium can be a tangible device that can retain and store instructions for use by an instruction execution device. The computer readable storage medium may be, for example, but is not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. A non-exhaustive list of more specific examples of the computer readable storage medium includes the following: a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanically encoded device such as punch-cards or raised structures in a groove having instructions recorded thereon, and any suitable combination of the foregoing. A computer readable storage medium, as used herein, is not to be construed as being transitory signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through a waveguide or other transmission media (e.g., light pulses passing through a fiber-optic cable), or electrical signals transmitted through a wire. 
     Computer readable program instructions described herein can be downloaded to respective computing/processing devices from a computer readable storage medium or to an external computer or external storage device via a network, for example, the Internet, a local area network, a wide area network and/or a wireless network. The network may comprise copper transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers and/or edge servers. A network adapter card or network interface in each computing/processing device receives computer readable program instructions from the network and forwards the computer readable program instructions for storage in a computer readable storage medium within the respective computing/processing device. 
     Computer readable program instructions for carrying out operations of the present invention may be assembler instructions, instruction-set-architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state-setting data, or either source code or object code written in any combination of one or more programming languages, including an object oriented programming language such as Smalltalk, C++ or the like, and conventional procedural programming languages, such as the “C” programming language or similar programming languages. The computer readable program instructions may execute entirely on the user&#39;s computer, partly on the user&#39;s computer, as a stand-alone software package, partly on the user&#39;s computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user&#39;s computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider). In some embodiments, electronic circuitry including, for example, programmable logic circuitry, field-programmable gate arrays (FPGA), or programmable logic arrays (PLA) may execute the computer readable program instructions by utilizing state information of the computer readable program instructions to personalize the electronic circuitry, in order to perform aspects of the present invention. 
     Aspects of the present invention are described herein with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer readable program instructions. 
     These computer readable program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. These computer readable program instructions may also be stored in a computer readable storage medium that can direct a computer, a programmable data processing apparatus, and/or other devices to function in a particular manner, such that the computer readable storage medium having instructions stored therein comprises an article of manufacture including instructions which implement aspects of the function/act specified in the flowchart and/or block diagram block or blocks. 
     The computer readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable apparatus or other device to produce a computer implemented process, such that the instructions which execute on the computer, other programmable apparatus, or other device implement the functions/acts specified in the flowchart and/or block diagram block or blocks. 
     The flowchart and block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of instructions, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems that perform the specified functions or acts or carry out combinations of special purpose hardware and computer instructions. 
     The descriptions of the various embodiments of the present invention have been presented for purposes of illustration, but are not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The terminology used herein was chosen to best explain the principles of the embodiment, the practical application or technical improvement over technologies found in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.