conan graph build-order¶
$ conan graph build-order -h
WARN: Downgrading cache from Conan 2.3.2 to 2.1.0
usage: conan graph build-order [-h] [-f FORMAT] [-v [V]] [-cc CORE_CONF]
[--name NAME] [--version VERSION] [--user USER]
[--channel CHANNEL] [--requires REQUIRES]
[--tool-requires TOOL_REQUIRES] [-b BUILD]
[-r REMOTE | -nr] [-u [UPDATE]] [-pr PROFILE]
[-pr:b PROFILE_BUILD] [-pr:h PROFILE_HOST]
[-pr:a PROFILE_ALL] [-o OPTIONS]
[-o:b OPTIONS_BUILD] [-o:h OPTIONS_HOST]
[-o:a OPTIONS_ALL] [-s SETTINGS]
[-s:b SETTINGS_BUILD] [-s:h SETTINGS_HOST]
[-s:a SETTINGS_ALL] [-c CONF] [-c:b CONF_BUILD]
[-c:h CONF_HOST] [-c:a CONF_ALL] [-l LOCKFILE]
[--lockfile-partial]
[--lockfile-out LOCKFILE_OUT]
[--lockfile-clean]
[--lockfile-overrides LOCKFILE_OVERRIDES]
[--order-by {recipe,configuration}] [--reduce]
[path]
Compute the build order of a dependency graph.
positional arguments:
path Path to a folder containing a recipe (conanfile.py or
conanfile.txt) or to a recipe file. e.g.,
./my_project/conanfile.txt.
options:
-h, --help show this help message and exit
-f FORMAT, --format FORMAT
Select the output format: json
-v [V] Level of detail of the output. Valid options from less
verbose to more verbose: -vquiet, -verror, -vwarning,
-vnotice, -vstatus, -v or -vverbose, -vv or -vdebug,
-vvv or -vtrace
-cc CORE_CONF, --core-conf CORE_CONF
Global configuration for Conan
--name NAME Provide a package name if not specified in conanfile
--version VERSION Provide a package version if not specified in
conanfile
--user USER Provide a user if not specified in conanfile
--channel CHANNEL Provide a channel if not specified in conanfile
--requires REQUIRES Directly provide requires instead of a conanfile
--tool-requires TOOL_REQUIRES
Directly provide tool-requires instead of a conanfile
-b BUILD, --build BUILD
Optional, specify which packages to build from source.
Combining multiple '--build' options on one command
line is allowed. Possible values: --build="*" Force
build from source for all packages. --build=never
Disallow build for all packages, use binary packages
or fail if a binary package is not found, it cannot be
combined with other '--build' options. --build=missing
Build packages from source whose binary package is not
found. --build=cascade Build packages from source that
have at least one dependency being built from source.
--build=[pattern] Build packages from source whose
package reference matches the pattern. The pattern
uses 'fnmatch' style wildcards. --build=~[pattern]
Excluded packages, which will not be built from the
source, whose package reference matches the pattern.
The pattern uses 'fnmatch' style wildcards.
--build=missing:[pattern] Build from source if a
compatible binary does not exist, only for packages
matching pattern.
-r REMOTE, --remote REMOTE
Look in the specified remote or remotes server
-nr, --no-remote Do not use remote, resolve exclusively in the cache
-u [UPDATE], --update [UPDATE]
Will install newer versions and/or revisions in the
local cache for the given reference, or all in case no
argument is supplied. When using version ranges, it
will install the latest version that satisfies the
range. Also, if using revisions, it will update to the
latest revision for the resolved version range.
-pr PROFILE, --profile PROFILE
Apply the specified profile. By default, or if
specifying -pr:h (--profile:host), it applies to the
host context. Use -pr:b (--profile:build) to specify
the build context, or -pr:a (--profile:all) to specify
both contexts at once
-pr:b PROFILE_BUILD, --profile:build PROFILE_BUILD
-pr:h PROFILE_HOST, --profile:host PROFILE_HOST
-pr:a PROFILE_ALL, --profile:all PROFILE_ALL
-o OPTIONS, --options OPTIONS
Apply the specified options. By default, or if
specifying -o:h (--options:host), it applies to the
host context. Use -o:b (--options:build) to specify
the build context, or -o:a (--options:all) to specify
both contexts at once. Example: -o pkg:with_qt=true
-o:b OPTIONS_BUILD, --options:build OPTIONS_BUILD
-o:h OPTIONS_HOST, --options:host OPTIONS_HOST
-o:a OPTIONS_ALL, --options:all OPTIONS_ALL
-s SETTINGS, --settings SETTINGS
Apply the specified settings. By default, or if
specifying -s:h (--settings:host), it applies to the
host context. Use -s:b (--settings:build) to specify
the build context, or -s:a (--settings:all) to specify
both contexts at once. Example: -s compiler=gcc
-s:b SETTINGS_BUILD, --settings:build SETTINGS_BUILD
-s:h SETTINGS_HOST, --settings:host SETTINGS_HOST
-s:a SETTINGS_ALL, --settings:all SETTINGS_ALL
-c CONF, --conf CONF Apply the specified conf. By default, or if specifying
-c:h (--conf:host), it applies to the host context.
Use -c:b (--conf:build) to specify the build context,
or -c:a (--conf:all) to specify both contexts at once.
Example: -c tools.cmake.cmaketoolchain:generator=Xcode
-c:b CONF_BUILD, --conf:build CONF_BUILD
-c:h CONF_HOST, --conf:host CONF_HOST
-c:a CONF_ALL, --conf:all CONF_ALL
-l LOCKFILE, --lockfile LOCKFILE
Path to a lockfile. Use --lockfile="" to avoid
automatic use of existing 'conan.lock' file
--lockfile-partial Do not raise an error if some dependency is not found
in lockfile
--lockfile-out LOCKFILE_OUT
Filename of the updated lockfile
--lockfile-clean Remove unused entries from the lockfile
--lockfile-overrides LOCKFILE_OVERRIDES
Overwrite lockfile overrides
--order-by {recipe,configuration}
Select how to order the output, "recipe" by default if
not set.
--reduce Reduce the build order, output only those to build.
Use this only if the result will not be merged later
with other build-order
The conan graph build-order command computes the build order of the dependency graph for the recipe specified in path or in --requires/--tool-requires.
There are 2 important arguments that affect how this build order is computed:
The
--order-byargument can take 2 valuesrecipeandconfiguration, depending how we want to structure and parallelize our CI.The
--reduceargument will strip all packages in the order that doesn’t need to be built from source.
By default, the conan graph build-order will return the order for the full dependency graph, and it will annotate
in each element what needs to be done, for example "binary": "Cache" if the binary is already in the Conan Cache
and doesnt need to be built from source, and "binary": "Build", if it needs to be built from source.
Having the full order is necessary if we want to conan graph build-order-merge several build-orders into a single
one later, because having the full information allows to preserve the relative order that would otherwise be lost and
broken.
Consequently, the --reduce argument should only be used when we are directly going to use the result to do the
build, but not if we plan to later do a merge of the resulting build-order with other ones.
Let’s consider installing libpng and wanting to see the build order for this requirement ordered by recipe:
Warning
Please be aware that starting with Conan 2.1.0, using the –order-by argument is recommended, and its absence is deprecated. This argument will be removed in the near future. It is maintained for backward compatibility. Note that the JSON output will differ if you use the –order-by argument, changing from a simple list to a dictionary with extended information.
$ conan graph build-order --requires=libpng/1.5.30 --format=json --order-by=recipe
...
======== Computing the build order ========
{
"order_by": "recipe",
"reduced": false,
"order": [
[
{
"ref": "zlib/1.3#06023034579559bb64357db3a53f88a4",
"depends": [],
"packages": [
[
{
"package_id": "d62dff20d86436b9c58ddc0162499d197be9de1e",
"prev": "54b9c3efd9ddd25eb6a8cbf01860b499",
"context": "host",
"binary": "Cache",
"options": [],
"filenames": [],
"depends": [],
"overrides": {},
"build_args": null
}
]
]
}
],
[
{
"ref": "libpng/1.5.30#ed8593b3f837c6c9aa766f231c917a5b",
"depends": [
"zlib/1.3#06023034579559bb64357db3a53f88a4"
],
"packages": [
[
{
"package_id": "60778dfa43503cdcda3636d15124c19bf6546ae3",
"prev": "ad092d2e4aebcd9d48a5b1f3fd51ba9a",
"context": "host",
"binary": "Download",
"options": [],
"filenames": [],
"depends": [],
"overrides": {},
"build_args": null
}
]
]
}
]
]
}
Firstly, we can see the zlib package, as libpng depends on it. The output is sorted by recipes as we passed with the –order-by argument; however, we might prefer to see it sorted by configurations instead. For that purpouse use the –order-by argument with value configuration.
$ conan graph build-order --requires=libpng/1.5.30 --format=json --order-by=configuration
...
======== Computing the build order ========
{
"order_by": "configuration",
"reduced": false,
"order": [
[
{
"ref": "zlib/1.3#06023034579559bb64357db3a53f88a4",
"pref": "zlib/1.3#06023034579559bb64357db3a53f88a4:d62dff20d86436b9c58ddc0162499d197be9de1e#54b9c3efd9ddd25eb6a8cbf01860b499",
"package_id": "d62dff20d86436b9c58ddc0162499d197be9de1e",
"prev": "54b9c3efd9ddd25eb6a8cbf01860b499",
"context": "host",
"binary": "Cache",
"options": [],
"filenames": [],
"depends": [],
"overrides": {},
"build_args": null
}
],
[
{
"ref": "libpng/1.5.30#ed8593b3f837c6c9aa766f231c917a5b",
"pref": "libpng/1.5.30#ed8593b3f837c6c9aa766f231c917a5b:60778dfa43503cdcda3636d15124c19bf6546ae3#ad092d2e4aebcd9d48a5b1f3fd51ba9a",
"package_id": "60778dfa43503cdcda3636d15124c19bf6546ae3",
"prev": "ad092d2e4aebcd9d48a5b1f3fd51ba9a",
"context": "host",
"binary": "Download",
"options": [],
"filenames": [],
"depends": [
"zlib/1.3#06023034579559bb64357db3a53f88a4:d62dff20d86436b9c58ddc0162499d197be9de1e#54b9c3efd9ddd25eb6a8cbf01860b499"
],
"overrides": {},
"build_args": null
}
]
]
}
If we now apply the --reduce:
$ conan graph build-order --requires=libpng/1.5.30 --reduce --format=json --order-by=configuration
...
======== Computing the build order ========
{
"order_by": "configuration",
"reduced": false,
"order": []
}
As there are no binaries to build here, all binaries already exist. If we explicitly force to build some, the result would be only those that are going to be built:
$ conan graph build-order --requires=libpng/1.5.30 --build="libpng/*" --reduce --format=json --order-by=configuration
...
======== Computing the build order ========
{
"order_by": "configuration",
"reduced": false,
"order": [
[
{
"ref": "libpng/1.5.30#ed8593b3f837c6c9aa766f231c917a5b",
"pref": "libpng/1.5.30#ed8593b3f837c6c9aa766f231c917a5b:60778dfa43503cdcda3636d15124c19bf6546ae3#ad092d2e4aebcd9d48a5b1f3fd51ba9a",
"package_id": "60778dfa43503cdcda3636d15124c19bf6546ae3",
"prev": null,
"context": "host",
"binary": "Build",
"options": [],
"filenames": [],
"depends": [],
"overrides": {},
"build_args": "--require=libpng/1.5.30 --build=libpng/1.5.30"
}
]
]
}
Then it will contain exclusively the binary=Build nodes, but not the rest.
Note that it will also provide a build_args field with the arguments needed for a conan install <args> to fire the build of this package
in the CI agent.