Secara khusus, hal ini memungkinkan fungsi implementasi mengakses label, atribut, konfigurasi, dan penyedia dependensi target saat ini. Class ini memiliki metode untuk mendeklarasikan file output dan tindakan yang menghasilkannya.
Objek konteks pada dasarnya aktif selama durasi panggilan ke fungsi penerapan. Akses ke objek ini di luar fungsi terkait tidak akan berguna. Lihat halaman Aturan untuk mengetahui informasi selengkapnya.
Anggota
- tindakan
- aspect_ids
- attr
- bin_dir
- build_file_path
- build_setting_value
- konfigurasi
- coverage_instrumented
- created_actions
- default_provider
- disabled_features
- exec_groups
- executable
- expand_location
- expand_make_variables
- fitur
- file
- file
- fragmen
- genfiles_dir
- host_configuration
- host_fragments
- info_file
- label
- new_file
- output
- resolve_command
- resolve_tools
- rule
- runfiles
- split_attr
- target_platform_has_constraint
- toolchain
- var
- version_file
- workspace_name
tindakan
actions ctx.actionsBerisi metode untuk mendeklarasikan file output dan tindakan yang menghasilkannya.
aspect_ids
list ctx.aspect_idsDaftar ID untuk semua aspek yang diterapkan ke target. Hanya tersedia di fungsi implementasi aspek.
attr
struct ctx.attrStruktur untuk mengakses nilai atribut. Nilai diberikan oleh pengguna (jika tidak, nilai default akan digunakan). Atribut struct dan jenis nilainya sesuai dengan kunci dan nilai kamus
attrs
yang diberikan ke fungsi rule
. Lihat contoh penggunaan.
bin_dir
root ctx.bin_dirRoot yang sesuai dengan direktori bin.
build_file_path
string ctx.build_file_pathJalur ke file BUILD untuk aturan ini, relatif terhadap root sumber.
build_setting_value
unknown ctx.build_setting_valueEksperimental. Bidang ini bersifat eksperimental dan dapat berubah sewaktu-waktu. Jangan mengandalkannya.
Nilai setelan build yang diwakili oleh target saat ini. Akses ke kolom ini untuk aturan yang tidak menetapkan atribut build_setting
dalam definisi aturannya akan menghasilkan error.
konfigurasi
configuration ctx.configurationKonfigurasi default. Lihat jenis konfigurasi untuk detail selengkapnya.
coverage_instrumented
bool ctx.coverage_instrumented(target=None)Menampilkan apakah instrumentasi cakupan kode harus dibuat saat melakukan tindakan kompilasi untuk aturan ini atau, jika
target
disediakan, aturan yang ditentukan oleh Target tersebut. (Jika Target aturan Starlark atau non-aturan diberikan, nilai ini akan menampilkan False.) Memeriksa apakah sumber aturan saat ini (jika tidak ada Target yang disediakan) atau sumber Target harus diinstrumentasikan berdasarkan setelan konfigurasi --instrumentation_filter dan --instrument_test_targets. Hal ini berbeda dengan coverage_enabled
dalam konfigurasi, yang mencatat apakah pengumpulan data cakupan diaktifkan untuk seluruh operasi, tetapi tidak mencatat apakah target tertentu harus diinstrumentasi.
Parameter
Parameter | Deskripsi |
---|---|
target
|
Target; or None ;
default = NoneTarget yang menentukan aturan. Jika tidak diberikan, setelan defaultnya adalah aturan saat ini. |
created_actions
StarlarkValue ctx.created_actions()Untuk aturan dengan _skylark_testable yang ditetapkan ke
True
, hal ini akan menampilkan penyedia Actions yang mewakili semua tindakan yang dibuat sejauh ini untuk aturan saat ini. Untuk semua aturan lainnya, menampilkan None
. Perhatikan bahwa penyedia tidak diperbarui saat tindakan berikutnya dibuat, sehingga Anda harus memanggil fungsi ini lagi jika ingin memeriksanya. Ini dimaksudkan untuk membantu menulis pengujian untuk fungsi bantuan penerapan aturan, yang dapat mengambil objek
ctx
dan membuat tindakan di dalamnya.
default_provider
Provider ctx.default_providerTidak digunakan lagi. Sebagai gantinya, gunakan DefaultInfo.
disabled_features
list ctx.disabled_featuresKumpulan fitur yang secara eksplisit dinonaktifkan oleh pengguna untuk aturan ini.
exec_groups
ExecGroupCollection ctx.exec_groupsKumpulan grup eksekusi yang tersedia untuk aturan ini, diindeks berdasarkan namanya. Akses dengan
ctx.exec_groups[name_of_group]
.
dapat dieksekusi
struct ctx.executable
struct
yang berisi file yang dapat dieksekusi yang ditentukan dalam atribut jenis label yang ditandai sebagai executable=True
. Kolom struct sesuai dengan nama atribut. Setiap nilai dalam struct adalah File
atau None
. Jika atribut opsional tidak ditentukan dalam aturan, nilai struct yang sesuai adalah None
. Jika jenis label tidak ditandai sebagai executable=True
, tidak ada kolom struct yang sesuai yang dihasilkan. Lihat contoh penggunaan.
expand_location
string ctx.expand_location(input, targets=[], short_paths=False)Memperluas semua template
$(location ...)
dalam string yang diberikan dengan mengganti $(location //x)
dengan jalur file output target //x. Perluasan hanya berfungsi untuk label yang mengarah ke dependensi langsung aturan ini atau yang secara eksplisit tercantum dalam argumen opsional targets
. $(location ...)
akan menyebabkan error jika target yang direferensikan memiliki beberapa output. Dalam hal ini, gunakan $(locations ...)
karena metode ini menghasilkan daftar jalur output yang dipisahkan spasi. Fungsi ini juga dapat digunakan dengan aman untuk satu file output.Fungsi ini berguna untuk memungkinkan pengguna menentukan perintah dalam file BUILD (seperti untuk
genrule
). Dalam kasus lain, sebaiknya manipulasi label secara langsung.
Parameter
Parameter | Deskripsi |
---|---|
input
|
wajib String yang akan diperluas. |
targets
|
sequence of Targets ;
default = []Daftar target untuk informasi pencarian tambahan. |
short_paths
|
default = Salah Menggunakan jalur relatif root, bukan jalur exec penuh |
None
.
expand_make_variables
string ctx.expand_make_variables(attribute_name, command, additional_substitutions)Tidak digunakan lagi. Sebagai gantinya, gunakan ctx.var untuk mengakses variabel.
Menampilkan string setelah memperluas semua referensi ke "Buat variabel". Variabel harus memiliki format berikut:
$(VAR_NAME)
. Selain itu, $$VAR_NAME
expands to $VAR_NAME
. Examples:ctx.expand_make_variables("cmd", "$(MY_VAR)", {"MY_VAR": "Hi"}) # == "Hi" ctx.expand_make_variables("cmd", "$$PWD", {}) # == "$PWD" Additional variables may come from other places, such as configurations. Note that this function is experimental.Parameters
Parameter | Description |
---|---|
attribute_name
|
required The attribute name. Used for error reporting. |
command
|
required The expression to expand. It can contain references to "Make variables". |
additional_substitutions
|
required Additional substitutions to make beyond the default make variables. |
features
list ctx.featuresThe set of features that are explicitly enabled by the user for this rule. See example of use.
file
struct ctx.fileA
struct
containing files defined in label type attributes marked as allow_single_file
. The struct fields correspond to the attribute names. The struct value is always a File
or None
. If an optional attribute is not specified in the rule then the corresponding struct value is None
. If a label type is not marked as allow_single_file
, no corresponding struct field is generated. It is a shortcut for:list(ctx.attr.<ATTR>.files)[0]In other words, use
file
to access the (singular) default output of a dependency. See example of use.
files
struct ctx.filesA
struct
containing files defined in label or label list type attributes. The struct fields correspond to the attribute names. The struct values are list
of File
s. It is a shortcut for:[f for t in ctx.attr.<ATTR> for f in t.files]In other words, use
files
to access the default outputs of a dependency. See example of use.
fragments
fragments ctx.fragmentsAllows access to configuration fragments in target configuration.
genfiles_dir
root ctx.genfiles_dirThe root corresponding to genfiles directory.
host_configuration
configuration ctx.host_configurationThe host configuration. See the configuration type for more details.
host_fragments
fragments ctx.host_fragmentsAllows access to configuration fragments in host configuration.
info_file
File ctx.info_fileThe file that is used to hold the non-volatile workspace status for the current build request. See documentation for --workspace_status_command for more information.
label
Label ctx.labelThe label of the target currently being analyzed.
new_file
File ctx.new_file(var1, var2=unbound, var3=unbound)DEPRECATED. Use ctx.actions.declare_file.
Creates a file object. There are four possible signatures to this method:
- new_file(filename): Creates a file object with the given filename in the current package.
- new_file(file_root, filename): Creates a file object with the given filename under the given file root.
- new_file(sibling_file, filename): Creates a file object in the same directory as the given sibling file.
- new_file(file_root, sibling_file, suffix): Creates a file object with same base name of the sibling_file but with different given suffix, under the given file root.
Does not actually create a file on the file system, just declares that some action will do so. You must create an action that generates the file. If the file should be visible to other rules, declare a rule output instead when possible. Doing so enables Blaze to associate a label with the file that rules can refer to (allowing finer dependency control) instead of referencing the whole rule.
Parameters
Parameter | Description |
---|---|
var1
|
string; or root; or File ;
required |
var2
|
string; or File ;
default = unbound |
var3
|
string ;
default = unbound |
outputs
structure ctx.outputsA pseudo-struct containing all the predeclared output files, represented by
File
objects. See the Rules page for more information and examples.This field does not exist on aspect contexts, since aspects do not have predeclared outputs.
The fields of this object are defined as follows. It is an error if two outputs produce the same field name or have the same label.
- If the rule declares an
outputs
dict, then for every entry in the dict, there is a field whose name is the key and whose value is the correspondingFile
. - For every attribute of type
attr.output
that the rule declares, there is a field whose name is the attribute's name. If the target specified a label for that attribute, then the field value is the correspondingFile
; otherwise the field value isNone
. - For every attribute of type
attr.output_list
that the rule declares, there is a field whose name is the attribute's name. The field value is a list ofFile
objects corresponding to the labels given for that attribute in the target, or an empty list if the attribute was not specified in the target. - (Deprecated) If the rule is marked
executable
ortest
, there is a field named"executable"
, which is the default executable. It is recommended that instead of using this, you pass another file (either predeclared or not) to theexecutable
arg ofDefaultInfo
.
resolve_command
tuple ctx.resolve_command(command='', attribute=None, expand_locations=False, make_variables=None, tools=[], label_dict={}, execution_requirements={})(Experimental) Returns a tuple
(inputs, command, input_manifests)
of the list of resolved inputs, the argv list for the resolved command, and the runfiles metadata required to run the command, all of them suitable for passing as the same-named arguments of the ctx.action
method.Note for Windows users: this method requires Bash (MSYS2). Consider using
resolve_tools()
instead (if that fits your needs).
Parameters
Parameter | Description |
---|---|
command
|
default = '' Command to resolve. |
attribute
|
string; or None ;
default = NoneName of the associated attribute for which to issue an error, or None. |
expand_locations
|
default = False Shall we expand $(location) variables? See ctx.expand_location() for more details. |
make_variables
|
dict; or None ;
default = NoneMake variables to expand, or None. |
tools
|
sequence of Targets ;
default = []List of tools (list of targets). |
label_dict
|
default = {} Dictionary of resolved labels and the corresponding list of Files (a dict of Label : list of Files). |
execution_requirements
|
default = {} Information for scheduling the action to resolve this command. See tags for useful keys. |
resolve_tools
tuple ctx.resolve_tools(tools=[])Returns a tuple
(inputs, input_manifests)
of the depset of resolved inputs and the runfiles metadata required to run the tools, both of them suitable for passing as the same-named arguments of the ctx.actions.run
method.In contrast to
ctx.resolve_command
, this method does not require that Bash be installed on the machine, so it's suitable for rules built on Windows.
Parameters
Parameter | Description |
---|---|
tools
|
sequence of Targets ;
default = []List of tools (list of targets). |
rule
rule_attributes ctx.ruleRule attributes descriptor for the rule that the aspect is applied to. Only available in aspect implementation functions.
runfiles
runfiles ctx.runfiles(files=[], transitive_files=None, collect_data=False, collect_default=False, symlinks={}, root_symlinks={})Creates a runfiles object.
Parameters
Parameter | Description |
---|---|
files
|
sequence of Files ;
default = []The list of files to be added to the runfiles. |
transitive_files
|
depset of Files; or None ;
default = NoneThe (transitive) set of files to be added to the runfiles. The depset should use the default order (which, as the name implies, is the default).
|
collect_data
|
default = False Use of this parameter is not recommended. See runfiles guide. Whether to collect the data runfiles from the dependencies in srcs, data and deps attributes. |
collect_default
|
default = False Use of this parameter is not recommended. See runfiles guide. Whether to collect the default runfiles from the dependencies in srcs, data and deps attributes. |
symlinks
|
dict; or depset of SymlinkEntrys ;
default = {}Either a SymlinkEntry depset or the map of symlinks, prefixed by workspace name, to be added to the runfiles. See Runfiles symlinks in the rules guide. |
root_symlinks
|
dict; or depset of SymlinkEntrys ;
default = {}Either a SymlinkEntry depset or a map of symlinks to be added to the runfiles. See Runfiles symlinks in the rules guide. |
split_attr
struct ctx.split_attrA struct to access the values of attributes with split configurations. If the attribute is a label list, the value of split_attr is a dict of the keys of the split (as strings) to lists of the ConfiguredTargets in that branch of the split. If the attribute is a label, then the value of split_attr is a dict of the keys of the split (as strings) to single ConfiguredTargets. Attributes with split configurations still appear in the attr struct, but their values will be single lists with all the branches of the split merged together.
target_platform_has_constraint
bool ctx.target_platform_has_constraint(constraintValue)Returns true if the given constraint value is part of the current target platform.
Parameters
Parameter | Description |
---|---|
constraintValue
|
required The constraint value to check the target platform against. |
toolchains
ToolchainContext ctx.toolchainsToolchains for the default exec group of this rule.
var
dict ctx.varDictionary (String to String) of configuration variables.
version_file
File ctx.version_fileThe file that is used to hold the volatile workspace status for the current build request. See documentation for --workspace_status_command for more information.
workspace_name
string ctx.workspace_nameThe workspace name as defined in the WORKSPACE file.