Glossary

Artefact

Artefact is a term for an item, usually a file, created by a build step and added to the Artefact Store.

Some examples of artefacts are:

• a Fortran file

• a compiled object file

• an executable file

These exist as files in the file system and paths in the Artefact Store.

Artefact Collection

A collection of Artefacts in the Artefact Store.

These entries are usually a list of file paths or objects, sometimes a Source Tree, but could be anything created by one step and consumed by another.

As an example, a Fortran preprocessing step might create a list of output paths as artefact_store['preprocessed fortran'] = my_results. A subsequent step could read this list.

Artefacts Getter

A helper class which a Step uses to find artefacts in the Artefact Store. Fab’s built-in steps come with sensible defaults so the user doesn’t have to write unnecessary config.

As an example, the Fortran preprocessor has a default artefact getter which reads “.F90” files from the Artefact Collection called "INITIAL_SOURCE".

Artefact getters are derived from ArtefactsGetter.

Artefact Store

The artefact store holds collections created and used by build steps.

Fab passes the growing store to each step in turn, where they typically read a collection and create a new one for the next step.

Build Tree

A mapping of filenames to Analysis results. This subset of the Source Tree contains only the files needed to build one target (Root Symbol). It’s created in the analysis step and used by the Fortran compilation step. When building a library, there is no root symbol and the entire source tree is included in a single build tree.

Fab Workspace

The folder in which all Fab output is created, for all build projects. Defaults to ~/fab-workspace, and can be overridden by the $FAB_WORKSPACE environment variable or the fab_workspace argument to the BuildConfig constructor. See also Configure the Fab Workspace

Incremental Build

This term refers to Fab’s ability to avoid reprocessing an artefact if the output is already available. For example, if the user has previously built the project, there will likely be object files Fab can use to avoid recompilation.

Prebuild

This term has much overlap with the term Incremental Build. It refers to artefacts that were built by another user, which can be copied to avoid reprocessing artefacts. Technical details on how this works can be found in Incremental & Prebuilds.

Project Workspace

A folder inside the Fab Workspace, containing all source and output from a build config.

Root Symbol

The name of a Fortran PROGRAM, or "main" for C code. Fab builds an executable for every root symbol it’s given.

Source Tree

The analyse step produces a dependency tree of the entire project source. This is represented as a mapping from Path to AnalysedDependent. The AnalysedDependent’s file dependencies are Paths, which refer to other entries in the mapping, and which define the tree structure. This is called the source tree.

Step

A step performs a function in the build process.

Each step typically reads from, and adds to, an in-memory Artefact repository called the Artefact Store. Steps are derived from the Step base class.