formax is a tool for developing and executing fast, powerful and user-friedly character-based, interactive database applications. The basic concepts of Oracle SQL-Forms 3.0 are combined with curses as the terminal interface, ODBC for universal database access and Javascript as the trigger language. The best ideas for a powerful user interface from Emacs, Clipper, SAP and Lotus/1-2-3. The result is the most effective solution possible for the end-user.
formax forms access the database and generate a screen that presents the data. The source form (.inp in practice a sql-script to create a sqlite3 database) is compiled into a binary (.frm in practice a sqlite3 database), that is run by the runtime component. The form is used to view and edit data in a database-driven manner. The environment supplies built-in record creation, query, delete and update modes, each with its own default data manipulations. This minimizes the need for program code. formax can be seen as a "No-code RAD" (Rapid Application Development).
The running form has an event driven interface and implements event-handling functions called triggers which are automatically invoked at critical steps in the processing of records and the receipt of keyboard strokes. Different triggers may be called before, during, and after each critical step. Each event function is initially a stub, containing a default action or nothing. Programming therefore generally consists of modifying the contents of these triggers in order to alter the default behavior if necessary.
fromax consists of the following programs, or components, that you can execute independently from the command line.
makeform is a shell script which can produce the sql
script (.inp) which in turn can create the form database
(.frm) by using the sqlite3 utility. The produced sql
script represents in practice the source code of the
form application and can be edited to change the default
behaviour or to add objects to the form.
editform can edit the form database with a form.
NOT YET IMPLEMENTED.
Execute forms (.frm) interactively on a terminal by the
end-user.
Parser for a natural query language. Translats human
properties to SQL where clauses.
Regular expression engine for validating user entered
data.
See: github.com/kokke/tiny-regex-c
Javascript engine for 3GL triggers.
See: github.com/cesanta/elk
A formax application is made up of objects. These objects contain all the information that is needed for an application. They have a 1:1 relationship to the tables in the form-database and to the classes in the C++ source. In the source-code there is a separate class for every object for reading the form-database and for processing.
The primary object of a formax application is the form. A form is made up of additional objects. These objects link the form to database elements, such as columns and tables, and provide control over the flow of execution.
Describe each section or subsection of the form, and serve as the basis of default database interaction.
Represent columns or data entry areas and describe how the data should be displayed and validated an how an operator should interact with the data while it is entered.
Are collections of display information, such as constant text. All fields are displayed on some page.
Are sets of processing commands associated with event points, such as when a particular function key is pressed by the operator.
When a form is executed fromax follows a pre-defined set of rules for how actions should occur. These actions include navigation whithin the application and the validation of data. Within the processing rules, you can customize the default behaviour to meet the needs of your application.
All processing centers around events. Put simply, events are things that occur when a form is exeecuted. formax knows about events and handles them by executing functions. Note that during processing, events are usually nested. That is, the occurence of one event usually invokes functions that invoke other events. Inherent in the functions that events invoke - and that are invoked by your tiggers - are the processes of navigation and validation.
Every function that an event calls might have on or more trigger point associated with it. A trigger point is temporal place in an event with a specific trigger type is associated. Trigger points and triggers are your primary tools for modifying the way that formax handles, or processes, a particular event.
Navigation is an internal function that is invoked by specific events. formax perfoms navigation primarily to move the cursor from one location to another. The main concepts of navigation are the navigation unit and the cursor. The navigation unit is always defined as a specific form, block, record or field in the form, or as outside the form.
Validation is an internal function that is invoked by specific events. Validation is the process by which formax determines whether the data in an object is valid or correct.
Events invoke functions, which have trigger points. When formax processes a trigger point, it executes, or fires, the associated trigger. Every trigger pont has a specific type of trigger associated with it.
Current 0.9.0 is ALPHA and unusable - the generator can only create a single-block single-page form. runform can display the page - wait for a key - and exit.
1.0.0 will be able to create, retrieve, update and delete (CRUD) records in a table by a single-block, single-page, single-row form. Expected 08/2024.
- multiple blocks master-detail
- form for forms
- dev guide en
- user guide in en, de, fr, ...
- man pages
- import script for page layout
- menue multiple forms
- cqy.y: resolv 5 shift/reduce conflicts
- sap-like batchinput
- triggers with embedded javascript (elk)
- help
- domains with central maintaining
- direct field keys 1..9 ?
- key macro
- multiple databases
"LineCodePage"="ISO-8859-15:1999 (Latin-9, \"euro\")"
formax is implemented in pure C++ without calls to the OS. Interface to the user is solely done with curses-lib. Interface to the database is solely through ODBC. Both libraries are not used directly but wrapped by the Screen and Record classes. Record is a simple ORM inspired by rails ActiceRecord. The form-database is a sqlite-database. The form generator builds a SQL script that creates the default database.
Everything is compiled with -Wall -Werror and memchecked with valgrind. Only int and char types are used and where possible static variables are used. Sourcecode lines are grouped into blocks of maximum 40. These groups have a top comment which explains the purpose. Other commenting is only on special cases.
runform.cpp holds main() and has the only OS-interfaces for running and checking the command line. record.cpp calls ODBC and screen.cpp calls curses. All the other sources are pure C++ without any external library calls. For every main object is an r-source for reading the form database and a separate source for the class. The central Function class holds all the event functions.
One character variable names (pattern like jquery $) are used for some fundamental values:
| V | Description | Type | Source |
|---|---|---|---|
| t | char* target with size | Macro | runform.h |
| f | current Form object | Variable | runform.h |
| d | query result data | Variable | qdata.h |
| w | query result pointer | Method | qdata.h |
| v | query result string | Type | qdata.h |
| c | query result transfer | Type | qdata.h |
| n | query result to_int | Type | qdata.h |
| i | loop integer | Variable | |
| s | status integer | Variable | |
| q | query result object | Type | qdata.h |
| e | error messages array | Type | rerror.h |
| d | curses stdscr windows | Type | screen.h |
| b | blocks array | Variable | form.h |
| l | fields array | Variable | form.h |
| p | pages array | Variable | form.h |
2 spaces indenting is used and the top level of functions is not indented. Use 1 space between keyword and opening bracket. Do not use space between function name and opening bracket. Opening curly bracket is always at the same line as keyword (for, while, do, switch, if, ...). Bool is not compared - no if (ispresent == NULL) or (isempty[0] == '\0') just use !ispresent or *isempty.
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commenting
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style
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bool
Simplified BSD License
Copyright (c) 2024, Axel K. Reinhold
All rights reserved.