Provided by: justbuild_1.5.1-1ubuntu2_amd64 
NAME
just-mrrc - The format of the configuration used by just-mr(1)
DESCRIPTION
The file 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.
Location objects
A location is a JSON object with the keys "root", "path", and "base".
The value for key "root" is either "workspace", "home", or "system", which have the following meanings:
• "workspace" refers to the root of the workspace in which the just-mr invocation was issued (not the
workspace of the requested main repository). This location root is ignored if just-mr was not invoked
from inside a workspace.
• "home" refers to the user’s home directory.
• "system" refers to the system root /.
The value for key "path" is the relative path of the item to locate within the location root.
The value for key "base" is a relative path within the location root. This path is only relevant for
locations of config files. If such a config file contains relative paths, those will be resolved
relative to the specified base. If omitted, the default value "." is used.
The just-mrrc format
The just-mrrc is given by a JSON object.
• The value for the key "config lookup order" is a JSON list of location objects, specifying where to
look for multi-repository configurations (see just-mr-repository-config(5) for more detail). The
lookup is performed in the same order the location objects appear in the list.
• The value for the key "absent", if provided, is a JSON list of location objects to search for a file
specifying the list of absent repositories.
• The value for the key "local build root" is a single location object, specifying the path to use as the
local build root. For more details, see just-mr(1).
• The value for the key "checkout locations" is a single location object, specifying the path to the file
describing checkout locations and additional mirror locations. For more details, see just-mr(1).
• The value for the key "distdirs" is a JSON list of location objects, specifying where to look for
distribution files (usually collected via the subcommand fetch). The lookup is performed in the same
order the location objects appear in the list. For more details, see just-mr(1).
• The value for the key "just" is a single location object, specifying the path to the justbuild binary
to use for execution, if just-mr is used as a launcher.
• The value for the key "git" is a single location object, specifying the path to the git binary to use
in the instances when just-mr needs to shell out.
• The value for the key "local launcher", if given, is list of strings setting the default for local
launcher for just-mr; command-line arguments take precedence over the value in the configuration file.
If the key "local launcher" is absent, the default ["env", "--"] is assumed.
• The value for the key "log limit", if given, sets the default value for the log limit, that can be
overridden by the command-line options.
• The value for the key "restrict stderr log limit", if given, sets the default value for the restriction
of the log limit on console; this value can be overridden by the command-line option.
• The value "log files", if given, has to be a list of location objects, specifying additional log files,
on top of those specified on the command line.
• The value for the key "remote execution" is a JSON object specifying the remote execution options for
just-mr.
For subkey "address" the value is a string specifying the remote execution address in a NAME:PORT format.
For subkey "compatible" the value is a flag which specifies whether the remote endpoint uses the original
remote execution protocol.
Each subkey value can be overwritten by its corresponding command-line argument.
• The value for the key "remote serve" is a JSON object specifying the remote serve options for just-mr.
For subkey "address" the value is a string specifying the remote serve address in a NAME:PORT format.
Each subkey value can be overwritten by its corresponding command-line argument.
• The value for the key "authentication" is a JSON object specifying client-side authentication options
for just-mr.
For subkey "ca cert" the value is a single location object specifying the path to a TLS CA certificate.
For subkey "client cert" the value is a single location object specifying the path to a TLS client
certificate.
For subkey "client key" the value is a single location object specifying the path to a TLS client key.
Each subkey value can be overwritten by its corresponding command-line argument.
• The value for the key "remote-execution properties", if provided, has to be a list of strings. Each
entry is forwarded as --remote-execution-property to the invocation of the build tool, if just-mr is
used as a launcher.
• The value for the key "max attempts", if provided, has to be a number. If a remote procedure call
(rpc) returns grpc::StatusCode::UNAVAILABLE, that rpc is retried at most this number of times.
• The value for the key "initial backoff seconds", if provided, has to be a number. Before retrying an
rpc the second time, the client will wait the given amount of seconds plus a jitter, to better
distribute the workload.
• The value for the key "max backoff seconds", if provided, has to be a number. Normally, on subsequent
retries, the backoff time is doubled; this number specifies the maximal time between attempts of an
rpc, not counting the jitter.
• The value for the key "just files" is a JSON object. The keys correspond to options that some
justbuild subcommands accept and require a file as argument. For each key, the value is a list of
location objects. When just-mr is used as a launcher and the invoked subcommand is known to support
this option, this option is set in the justbuild invocation with the first matching entry, if any. The
supported options are "config" and endpoint-configuration.
• The value for the key "just args" is a JSON object. Its keys are justbuild subcommands and its value
is a JSON list of strings. For the corresponding subcommand, these strings are prefixed to the
justbuild argument vector (after all other options provided through the rc file), if just-mr is used as
a launcher.
• The value for the key "rc files", if given, is a list of location objects. For those location objects
that refer to an existing file, this file is read as an additional rc file overlaying the given rc file
in the specified order; the value of "rc files" in the overlaying files is ignored.
In this way, an rc file committed to a repository can be allowed to set a sensible configuration,
remote-execution and serve end points, etc. This is particularly useful when simultaneously working on
several projects with different settings.
EXAMPLE
An example just-mrrc file could look like the following:
{ "rc files":
[ {"root": "workspace", "path": "rc.json"}
, {"root": "workspace", "path": "etc/rc.json"}
]
, "config lookup order":
[ {"root": "workspace", "path": "repos.json"}
, {"root": "workspace", "path": "etc/repos.json"}
, {"root": "home", "path": ".just-repos.json"}
, {"root": "system", "path": "etc/just-repos.json"}
]
, "absent":
[ {"root": "workspace", "path": "etc/absent.json"}
, {"root": "home", "path": ".just-absent"}
]
, "local build root": {"root": "home", "path": ".cache/just"}
, "checkout locations": {"root": "home", "path": ".just-local.json"}
, "local launcher": ["env", "--"]
, "log limit": 5
, "restrict stderr log limit": 4
, "log files": [{"root": "home", "path": ".log/just/latest-invocation"}]
, "distdirs": [{"root": "home", "path": ".distfiles"}]
, "just": {"root": "system", "path": "usr/bin/justbuild"}
, "git": {"root": "system", "path": "usr/bin/git"}
, "remote execution": {"address": "10.0.0.1:8980"}
, "remote-execution properties": ["image:development-v1.2.3"]
, "just args":
{ "build": ["-J", "64"]
, "install": ["-J", "64", "--remember"]
, "install-cas": ["--remember"]
}
, "just files":
{ "config":
[ {"root": "workspace", "path": "etc/config.json"}
, {"root": "home", "path": ".just-config"}
]
}
}
See also
just-mr(1), just-mr-repository-config(5)
JUST-MRRC(5)