FPReport

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Architecture

FPReport is a banded reporting tool.

It was designed from zero, to be able to run on a headless webserver, with minimal dependencies. An important use-case was a Linux server running in a container without X libraries installed. Creating a report is just placing squares with contents on a page, usually based on a data loop. This can be done entirely in-memory, and does not need a display or GUI.

Reports can be created entirely in code, or they can be read from a definition file. The default shipped file uses JSON as the format to store the report definition. The reports can also be designed visually, using a designer.

Once the report is created, it can be saved to disk, or rendered. Rendering is the act of creating visual output.

  • To PDF. The PDF renderer is the renderer of choice
  • To a series of images. The FPImage renderer creates a bitmap per page, and the bitmaps can be saved in a directory in any of the supported FPImage formats.
  • To HTML: each page is rendered as a HTML page using appropriate CSS markup.
Parts that cannot be rendered as HTML and CSS will be rendered as an image and placed in the HTML page.
  • To the LCL (a canvas).
This is in fact the basis of the preview, the designer and the printing support.
  • To an AggPas canvas. AggPas is a powerful graphics library, and this renderer is similar in scope to the FPImage renderer
  • To fpGUI - this can be used to preview the report in a FPGUI report


units

fpreport
To create a report in code, this unit is all that is necessary.
It contains the basic report, page, bands and elements.
fpreportstreamer
This unit contains the streamer, which reads/writes a report definition from/to file.
fpjsonreport
This unit contains a report class that can be dropped on a Lazarus form/Datamodule:
the report definition will be written to the form file.