Where the charts find Graphviz
The charts find dot.exe by DRAGLINT_DOT, settings.json, the installed layout, PATH, then the shared default.
Point the charts at a different Graphviz without editing anything: set DRAGLINT_DOT, or put a dot key in %APPDATA%\drag-lint\settings.json. A path you set that does not exist is an error naming where it was set; nothing set means the installed layout, then dot.exe on PATH, then the shared default.
Details
**The charts draw their pictures with Graphviz dot.exe; this page says where the
engine looks for it and how to point it somewhere else.** The text answers of
drag-lint ask and the Reports menu never need Graphviz: when no dot.exe is found
the text is still delivered, with NOTE the chart could not be drawn.
The order
The engine takes the first candidate that exists:
| step | where | how to set it |
|---|---|---|
| 1 | DRAGLINT_DOT | environment variable naming dot.exe |
| 2 | %APPDATA%\drag-lint\settings.json, key dot | { "dot": "C:\\Graphviz\\bin\\dot.exe" } |
| 3 | graphviz\bin\dot.exe in the charts files folder | an installed copy |
| 4 | graphviz\bin\dot.exe one folder above it | the Setup installer layout |
| 5 | graphviz\bin\dot.exe in the folder above charts\ | an earlier installed layout |
| 6 | dot.exe on PATH | a Graphviz you installed yourself |
| 7 | C:\Projects\GraphWiz\Graphviz-16.1.0-win64\bin\dot.exe | the shared default of a development machine |
A missing or unreadable settings.json, a missing key or an unset variable is
skipped. A path someone SET -- DRAGLINT_DOT or the settings.json key -- that does
not exist is an error naming where it was set, so a typo never silently picks another
file. When nothing exists the error names every place looked at, in order. PATH is
walked entry by entry; the current folder is never searched.
Examples
$env:DRAGLINT_DOT = 'C:\Graphviz\bin\dot.exe' (this session only)or, for good, in %APPDATA%\drag-lint\settings.json:
{ "dot": "C:\\Graphviz\\bin\\dot.exe" }See also
Charts and the IDE, Diagrams and Charts,
ask. Code: src\charts\DRagLint.Charts.Tools.pas (ResolveGraphvizDot).