conan graph explain¶
$ conan graph explain -h
WARN: Downgrading cache from Conan 2.2.3 to 2.0.17
usage: conan graph explain [-h] [-f FORMAT] [-v [V]] [--name NAME]
[--version VERSION] [--user USER]
[--channel CHANNEL] [--requires REQUIRES]
[--tool-requires TOOL_REQUIRES] [-b BUILD]
[-r REMOTE | -nr] [-u] [-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-packages] [--lockfile-clean]
[--lockfile-overrides LOCKFILE_OVERRIDES]
[--check-updates] [--build-require]
[--missing [MISSING]]
[path]
Explain what is wrong with the dependency graph, like report missing binaries
closest alternatives, trying to explain why the existing binaries do not match
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
--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 Will check the remote and in case a newer version
and/or revision of the dependencies exists there, it
will install those in the local cache. 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-packages Lock package-id and package-revision information
--lockfile-clean Remove unused entries from the lockfile
--lockfile-overrides LOCKFILE_OVERRIDES
Overwrite lockfile overrides
--check-updates Check if there are recipe updates
--build-require Whether the provided reference is a build-require
--missing [MISSING] A pattern in the form
'pkg/version#revision:package_id#revision', e.g:
zlib/1.2.13:* means all binaries for zlib/1.2.13. If
revision is not specified, it is assumed latest one.
The conan graph explain tries to give a more detailed explanation for a package that might be missing with the configuration provided and show the differences between the expected binary package and the available ones.
It helps to understand what is missing from the package requested, whether it is different options, different settings or different dependencies.
Example:
Imagine that we want to install the lib/1.0.0 that depends on dep/2.0.0 but we don’t have a binary yet, as the latest CI run only generated a binary for lib/1.0.0 using the previous version of dep. When we try to install the refere lib/1.0.0 it says:
$ conan install --requires=lib/1.0.0
...
ERROR: Missing prebuilt package for 'lib/1.0.0'
Now we can try to find a explanation for this:
$ conan graph explain --requires=lib/1.0.0
requires: dep/1.Y.Z
diff
dependencies
expected: dep/2.Y.Z
existing: dep/1.Y.Z
explanation: This binary has same settings and options, but different dependencies
In the same way, it can report when a package has a different option value and the output is also available in JSON format:
$conan graph explain --requires=lib/1.0.0 -o shared=True --format=json
...
{
"closest_binaries": {
"lib/1.0.0": {
"revisions": {
"dc0e384f0551386cd76dc29cc964c95e": {
"timestamp": 1692672717.68,
"packages": {
"b647c43bfefae3f830561ca202b6cfd935b56205": {
"info": {
"settings": {
"arch": "x86_64",
"build_type": "Release",
"compiler": "gcc",
"compiler.version": "11",
"os": "Linux"
},
"options": {
"shared": "False"
}
},
"diff": {
"platform": {},
"options": {
"expected": [
"shared=True"
],
"existing": [
"shared=False"
]
},
"settings": {},
"dependencies": {},
"explanation": "This binary was built with same settings but different options."
},
"remote": "conancenter"
}
}
}
}
}
}
}