Package: autojinja
autojinjaautojinjais a Python3 module that allows generating code inside any file usingJinja templatesin between comments. It aims to assist development workflows by using simple Python3 scripts that perform content generation of neighboring files, which enables generating code next to traditionally hand-made code efficiently.It includes :Content generation in any file that accepts commentsAbility to maintain hand-made code inside generated codeSimple integration in build pipelines and existing codebasesautojinjacan be seen as apreprocessorfor most file formats, and works great with any codebase as it automates writing code manually. It shines out even more when working with metadata files (such as XML or JSON files) that centralize information which later needs to be generated across various scattered files in the codebase.Installation$pipinstallautojinjaUsage$autojinjascript1.pyscript2.py$autojinja-a.Content generationContent generation consists in generating parts of an existing file thanks to dedicated sections that delimit where the generation takes place. This technique is made possible for all files accepting comments, and allows definingJinja templatesdirectly in such files without breaking them.For example, let's suppose we have a C++ file we want to generate inside. To do this, we need to write our Jinja template between[[[and]]]markers, followed by an[[[end]]]marker :// main.cpp#include<iostream>intmain(){std::cout<<"Hello world !"<<std::endl;// [[[ std::cout << "{{ value }}" << std::endl; ]]]  // Jinja template// [[[ end ]]]                                       // Code will be generated in betweenreturn0;}The template can then be generated with a Python3 script that provides thevaluevariable :# main.pyfromautojinjaimportCogTemplatetemplate=CogTemplate.from_file("main.cpp")template.context(value="Python here !").render_file()Calling the script will modify our C++ file as such :// main.cpp#include<iostream>intmain(){std::cout<<"Hello world !"<<std::endl;// [[[ std::cout << "{{ value }}" << std::endl; ]]]  // Jinja templatestd::cout<<"Python here !"<<std::endl;// [[[ end ]]]                                       // Code will be generated in betweenreturn0;}This technique is greatly inspired byCog, but adapted to work with Jinja templating engine. When performing generation again, the content inside the markers is entirely replaced by the new generation.Hand-made modificationsModification by hand of generated code is made possible by using special sections that are preserved across new generations. To do this, we need to name a section between<<[and]>>markers, followed by an<<[end]>>marker :// main.cpp#include<iostream>// [[[// int main() {////   std::cout << "{{ value }}" << std::endl;//   // <<[ impl ]>>  // Manually editable section named 'impl'//   return 0;//   // <<[ end ]>>   // End of section//// }// ]]]intmain(){std::cout<<"Python here !"<<std::endl;// <<[ impl ]>>  // Manually editable section named 'impl'std::cout<<"Modified by hand"<<std::endl;return1;// <<[ end ]>>   // End of section}// [[[ end ]]]When a new generation occurs, all previous sections are retrieved from the destination file and then reinserted into the new generation, inside each corresponding section with same name.All previous sections of a destination file must be reinserted when performing a new generation, otherwise it will be considered as code loss and generation will be aborted. Human intervention is required to deal with such scenarios.Integration in build pipelinesautojinjageneration mechanism can be integrated as a build step by listing all Python3 scripts that perform generation :$autojinjascript1.pydir/script2.py...autojinjaalso provides discover mechanisms to find and execute the concerned Python3 scripts in listed directories :-r -frecursively executes all Python3 scripts named__jinja__.py$autojinja-r-f.-r -trecursively executes all Python3 scripts whose first line containsautojinjakeyword (can be for instanceimport autojinjaorfrom autojinja import *)$autojinja-r-t.-aequivalent to-r -f -t$autojinja-a.Centralized metadata files (such as XML or JSON files) can easily be accessed inside Python3 scripts using environment variables and environment files :$autojinja-a.-eFILE1=/tmp/file1.xml-efile.envLinksDocumentationExamplesPyPIJinja2Cog