JUST REPOSITORY CONFIG(5) | File Formats Manual() JUST REPOSITORY CONFIG(5) | File Formats Manual()

just-repository-config - The format of the repository config used by justbuild(1)

justbuild’s repository configuration is read as JSON. Any other serialization describing the same JSON object is equivalent. We assume, that in JSON objects, each key occurs at most once; it is implementation defined how repetitions of the same key are treated.

Each repository can have multiple file roots. Each file root is defined as a non-empty JSON list with its first element being a string, which determines the type and semantic of the subsequent elements:

"file" refers to a file root that is located in the file system. The list has to be of length 2 and the second argument contains the path to the file root.
"git tree" refers to a file root that is available as part of a Git repository. The list has to be of length 2 or 3 with the remaining two elements being:
1.
The git tree hash, which is sufficient to describe the content of an entire tree including its sub-trees and blobs. The tree hash has to be specified in hex encoding.
2.
The path to a Git repository on the file system with the promise that it contains the aforementioned git tree hash; if this entry is missing, the root is considered absent and any target requiring this root has to come from a specified serve end point.

A single repository description is defined as a JSON object, which contains file roots, file names, and bindings to other repositories. Specifically the following fields are supported:

"workspace_root" contains the file root where source files are located. If this entry is missing for the main repository, justbuild will perform the normal workspace root resolution starting from the current working directory.
"target_root" contains the file root where the target files are located. If this entry is missing, the workspace root is taken.
"target_file_name" contains the file name of target files to use. If this entry is missing, the default target file name TARGETS is used.
"rule_root" contains the file root where the rule files are located. If this entry is missing, the target root is taken.
"rule_file_name" contains the file name of rule files to use. If this entry is missing, the default rule file name RULES is used.
"expression_root" contains the file root where the expression files are located. If this entry is missing, the rule root is taken.
"expression_file_name" contains the file name of expression files to use. If this entry is missing, the default expression file name EXPRESSIONS is used.
"bindings" contains a JSON object that defines bindings to other repositories by mapping local repository names to global ones. The object’s key is local name, while the value is a string representing the global name.

Note that any other unsupported field is accepted but ignored. There are no guarantees that any yet unsupported field may not become meaningful in future versions.

The repository configuration format is a JSON object with the following keys:

"main" contains a string, which defines the repository name to consider by default if not explicitly specified on the command line (i.e., via --main). This entry is optional and if omitted the empty string is used.
"repositories" contains a JSON object that defines all repositories by mapping global repository names to repository descriptions documented above. This entry is optional and if omitted an empty JSON object is used.

Although the repository configuration is human-readable and can be written by hand, in many cases it will be generated by an independent tool. just-mr(1) is one such tool that can be used for configuration generation, but not necessarily the only one.

justbuild(1), just-mr(1), just-mr-repository-config(5)