commands: Register user commands¶
cli: Command line interface¶
This module provides a method for parsing text commands
and calling the functions that implement them.
First, commands are registered
with a description of the arguments they take,
and with a function that implements the command.
Later, a Command
instance is used to parse
a command line, and optionally execute the command.
Incomplete command lines are supported,
so possible commands can be suggested.
In addition to registering command functions, there is a separate mechanism to support textual Command Aliases.
Text Commands¶
Synopsis:
command_name rv1 rv2 [ov1 [ov2]] [kn1 kv1] [kn2 kv2]
Text commands are composed of a command name, which can be multiple words,
followed by required positional arguments, rvX,
optional positional arguments, ovX,
and keyword arguments with a value, knX kvX.
Each argument has an associated Python argument name
(for keyword arguments it is the keyword, knX).
rvX, ovX, and kvX are the type-checked values.
If the argument name is the same as a Python keyword,
then an underscore appended to it to form the Python argument name.
The names of the optional arguments are used to
let them be given as keyword arguments as well.
Multiple value arguments are separated by commas
and the commas may be followed by whitespace.
Depending on the type of an argument, e.g., a color name,
whitespace can also appear within an argument value.
String argument values may be quoted with double or single quotes,
and Python’s textual escape sequences are recognized,
e.g., \N{LATIN CAPITAL LETTER A WITH RING ABOVE}
for the ångström sign,
Å.
Words in the command name may be truncated and are automatically completed to the first registered command with the given prefix. Likewise for keyword arguments.
Keywords are case sensitive, and are expected to be all lowercase.
Underscores are elided, but are documented as mixed case.
For example, a bg_color
keyword would be documented as bgColor
.
Registering Commands¶
To add a command, register()
the command name,
a description of the arguments it takes,
and the function to call that implements the command.
Command registration can be partially delayed to avoid importing
the command description and function until needed.
See register()
and delay_registration()
for details.
The description is either an instance of the Command Description class,
CmdDesc
, or a tuple with the arguments to the initializer.
The CmdDesc initializer takes tuples describing the required, optional,
and keyword arguments.
Each tuple contains tuples with the argument name and a type annotation
(see below).
Postconditions (see below) can be given too.
Command Functions¶
The command function arguments are expected to start with a session
argument. The rest of the arguments are assembled as keyword arguments,
as built from the command line and the command description.
The initial session
argument to a command function
is not part of the command description.
Type Annotations¶
There are many standard type notations and they should be reused as much as possible:
Type |
Annotation |
---|---|
|
|
|
|
|
|
|
|
tuple of 3 |
|
tuple of 3 |
|
tuple of 3 |
|
list of |
|
list of |
|
There is one special annotation: RestOfLine
that consumes
the rest of the command line as text.
Annotations are used to parse text and convert it to the appropriate type. Annotations can be extended with various specializers:
Specializer |
Example |
---|---|
|
|
|
|
|
|
|
|
|
|
|
enumerated values |
Creating Your Own Type Annotation¶
Annotations perform several functions: (1) to convert text to a value of the appropriate type, and (2) to give reasonable error messages.
See the Annotation
documentation for details.
Example
Here is a simple example:
import from chimerax.core.commands import Command, CmdDesc, RestOfLine
import from chimerax.core import errors
@register("echo", CmdDesc(optional=[('text', RestOfLine)]))
def echo(session, text=''):
print(text)
...
command = Command(session)
try:
status = command.run(text)
if status:
print(status)
except errors.UserError as err:
print(err, file=sys.stderr)
Command Aliases¶
Normally, command aliases are made with the alias command, but they can also be explicitly register with
alias()
and removed withremove_alias()
.An alias definition uses $n to refer to passed in arguments. $1 may appear more than once. $$ is $.
To register a multiword alias, quote the command name.
- class Aggregate(annotation, min_size=None, max_size=None, name=None, url=None, prefix=None)
Bases:
Annotation
Common class for collections of values.
- Aggregate(annotation, constructor, add_to, min_size=None, max_size=None,
name=None, url=None) -> annotation
- Parameters:
annotation – annotation for values in the collection.
min_size – minimum size of collection, default None.
max_size – maximum size of collection, default None.
name – optionally override name in error messages.
url – optionally give documentation URL.
prefix – optionally required prefix to aggregate.
This class is typically used via
ListOf
,SetOf
, orTupleOf
. The comma separator for aggregate values is handled by theCommand
class, so parsing is delegated to the underlying annotation.Subclasses need to set the constructor attribute and replace the add_to method.
- add_to(container, element)
Experimental API . Add to add an element to the container
- Parameters:
container – the container to add elements to
element – the element to add to the container
- Returns:
None for mutable containers, or a new container if immutable.
- parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class Alias(text, *, user=False, registry=None)
Bases:
object
alias a command
Returns a callable unnamed command alias.
- Parameters:
text – parameterized command text
user – true if alias was generated by user
The text is scanned for $n, where n is the n-th argument, $* for the rest of the line, and $$ for a single $.
- cmd_desc(**kw)
Experimental API . Return CmdDesc instance for alias
The
CmdDesc
keyword arguments other than ‘required’, ‘optional’, and ‘keyword’ can be used.
- class Annotation(name=None, url=None, html_name=None)
Bases:
object
Supported API. Base class for all annotations
Annotations encapsulate how to parse text into a particular type. Both subclasses and instances of subclasses can be used as annotations. An instance is used when an annotation is parameterized, e.g., with the length of a sequence.
Each annotation should have the following attributes:
- name¶
Set to textual description of the annotation, including the leading article, e.g., “an integer”.
- url¶
URL for help information.
- html_name()¶
A class or instance method that returns the HTML version of the name.
- classmethod html_name(name=None)
Supported API . Return HTML verison of name attribute
If the
url
attribute is set, then a HTML href using that URL is returned.
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- classmethod unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- exception AnnotationError(message, offset=0)
Bases:
UserError
,ValueError
Error, with optional offset, in an annotation
- class AttrNameArg(name=None, url=None, html_name=None)
Bases:
StringArg
Annotation for a Python attribute name
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class AxisArg(name=None, url=None, html_name=None)
Bases:
Annotation
Annotation for axis vector that can be 3 floats or “x”, or “y”, or “z” or two atoms.
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- class BoolArg(name=None, url=None, html_name=None)
Bases:
Annotation
Annotation for boolean literals
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class Bounded(annotation, min=None, max=None, *, inclusive=True, name=None, url=None, html_name=None)
Bases:
Annotation
Support bounded numerical values
Bounded(annotation, min=None, max=None, inclusive=True, name=None, url=None) -> an Annotation
- Parameters:
annotation – numerical annotation
min – optional lower bound
max – optional upper bound
inclusive – is the bound itself in the range
name – optional explicit name for annotation
url – optionally give documentation URL.
- parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class CenterArg(name=None, url=None, html_name=None)
Bases:
Annotation
Annotation for a center point that can be 3 floats or objects.
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- class CharacterArg(name=None, url=None, html_name=None)
Bases:
StringArg
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- class CmdDesc(required=(), optional=(), keyword=(), postconditions=(), required_arguments=(), non_keyword=(), hidden=(), url=None, synopsis=None, self_logging=False)
Bases:
object
Describe command arguments.
- Parameters:
required – required positional arguments sequence
optional – optional positional arguments sequence
keyword – keyword arguments sequence
required_arguments – sequence of argument names that must be given
non_keyword – sequence of optional arguments that cannot be keywords
hidden – sequence of keyword arguments that should be omitted from usage
url – URL to help page
synopsis – one line description
Each :param required:, :param optional:, :param keyword: sequence contains 2-tuples with the argument name and a type annotation. The command line parser uses the :param optional: argument names as additional keyword arguments. :param required_arguments: are for Python function arguments that don’t have default values, but should be given on the command line (typically keyword arguments, but could be used for syntactically optional arguments).
- copy()
Experimental API . Return a copy suitable for use with another function.
- class Command(session, *, registry=None)
Bases:
object
Keep track of (partially) typed command with possible completions
- Parameters:
session – the session to run the command in (may be None for testing)
- run(text, *, log=True, log_only=False, return_json=False, _used_aliases=None)
Experimental API . Parse and execute commands in the text
- Parameters:
text – The text to be parsed.
log – True (default) if commands are logged.
There are a couple side effects:
The automatically completed text is put in self.current_text.
Possible completions are in self.completions.
The prefix of the completions is in self.completion_prefix.
- class CoordSysArg(name=None, url=None, html_name=None)
Bases:
ModelArg
Annotation for coordinate system for AxisArg and CenterArg when specified as tuples of numbers. Coordinate system is specified as a Model specifier.
- classmethod parse(text, session)
Experimental API . Parse text and return an atomspec parse tree
- classmethod unparse(value, session)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class DottedTupleOf(annotation, min_size=None, max_size=None, name=None, url=None, prefix=None)
Bases:
Aggregate
Annotation for dot-separated lists of a single type
DottedListOf(annotation, min_size=None, max_size=None) -> annotation
- add_to(container, value)
Experimental API . Add to add an element to the container
- Parameters:
container – the container to add elements to
element – the element to add to the container
- Returns:
None for mutable containers, or a new container if immutable.
- constructor
alias of
tuple
- class DynamicEnum(values_func, name=None, url=None, html_name=None, case_sensitive=False)
Bases:
Annotation
Enumerated type where enumeration values computed from a function.
- property name
str(object=’’) -> str str(bytes_or_buffer[, encoding[, errors]]) -> str
Create a new string object from the given object. If encoding or errors is specified, then the object must expose a data buffer that will be decoded using the given encoding and error handler. Otherwise, returns the result of object.__str__() (if defined) or repr(object). encoding defaults to sys.getdefaultencoding(). errors defaults to ‘strict’.
- parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class EmptyArg(name=None, url=None, html_name=None)
Bases:
Annotation
Annotation for optionally missing ‘required’ argument
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class EnumOf(values, ids=None, abbreviations=None, name=None, url=None, case_sensitive=False)
Bases:
Annotation
Support enumerated types
EnumOf(values, ids=None, name=None, url=None) -> an Annotation
- Parameters:
values – iterable of values
ids – optional iterable of identifiers
abbreviations – if not None, then override allow_truncated
name – optional explicit name for annotation
url – optionally give documentation URL.
If the ids are given, then there must be one for each and every value, otherwise the values are used as the identifiers. The identifiers must all be strings.
- parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class FileNameArg(name=None, url=None, html_name=None)
Bases:
Annotation
Base class for Open/SaveFileNameArg
- classmethod parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class FloatArg(name=None, url=None, html_name=None)
Bases:
Annotation
Annotation for floating point literals
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class FloatOrDeltaArg(name=None, url=None, html_name=None)
Bases:
Annotation
Annotation for non-negative floating point literals, but if preceded by explicit +/- then interpreted as a delta
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class IntArg(name=None, url=None, html_name=None)
Bases:
Annotation
Annotation for integer literals
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class Limited(arg_name, min=None, max=None)
Bases:
Postcondition
Bounded numerical values postcondition
Limited(name, min=None, max=None) -> Postcondition
- Parameters:
arg_name – name of argument to check
min – optional inclusive lower bound
max – optional inclusive upper bound
If possible, use the Bounded annotation because the location of the error is the beginning of the argument, not the end of the line.
- check(kw_args)
Experimental API . Assert arguments match postcondition
- Parameters:
kw_args – dictionary of arguments that will be passed to command callback function.
- Returns:
True if arguments are consistent
- error_message()
Experimental API . Appropriate error message if check fails.
- Returns:
error message
- class ListOf(annotation, min_size=None, max_size=None, name=None, url=None, prefix=None)
Bases:
Aggregate
Annotation for lists of a single type
ListOf(annotation, min_size=None, max_size=None) -> annotation
- add_to(container, value)
Experimental API . Add to add an element to the container
- Parameters:
container – the container to add elements to
element – the element to add to the container
- Returns:
None for mutable containers, or a new container if immutable.
- constructor
alias of
list
- class ModelArg(name=None, url=None, html_name=None)
Bases:
AtomSpecArg
Parse command model specifier
- classmethod parse(text, session)
Experimental API . Parse text and return an atomspec parse tree
- classmethod unparse(model, session)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class ModelsArg(name=None, url=None, html_name=None)
Bases:
AtomSpecArg
Parse command models specifier
- classmethod parse(text, session)
Experimental API . Parse text and return an atomspec parse tree
- classmethod unparse(models, session)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class NoArg(name=None, url=None, html_name=None)
Bases:
Annotation
Annotation for keyword whose presence indicates True
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class NoneArg(name=None, url=None, html_name=None)
Bases:
Annotation
Annotation for ‘none’ (typically used with Or)
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class ObjectsArg(name=None, url=None, html_name=None)
Bases:
AtomSpecArg
Parse command objects specifier
- classmethod parse(text, session)
Experimental API . Parse text and return an atomspec parse tree
- class OnOffArg(name=None, url=None, html_name=None)
Bases:
BoolArg
BoolArg, but puts ‘on or off’ in usage text instead of ‘true or false’ where it would make more grammatical sense to do so
- class OpenFileNameArg(name=None, url=None, html_name=None)
Bases:
FileNameArg
Annotation for a file to open
- classmethod parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- class OpenFileNamesArg(name=None, url=None, html_name=None)
Bases:
Annotation
Annotation for opening one or more files
- classmethod parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class OpenFolderNameArg(name=None, url=None, html_name=None)
Bases:
FileNameArg
Annotation for a folder to open from
- classmethod parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- class Or(*annotations, name=None, url=None, html_name=None)
Bases:
Annotation
Support two or more alternative annotations
Or(annotation, annotation [, annotation]*, name=None, url=None) -> an Annotation
- Parameters:
name – optional explicit name for annotation
url – optionally give documentation URL.
- parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class PasswordArg(name=None, url=None, html_name=None)
Bases:
StringArg
Annotation for a password (should not be echoed to log)
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class PlaceArg(name=None, url=None, html_name=None)
Bases:
Annotation
Annotation for positioning matrix as 12 floats defining a 3 row, 4 column matrix where the first 3 columns are x,y,z coordinate axes, and the last column is the origin.
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- class Postcondition
Bases:
object
Base class for postconditions
- check(kw_args)
Experimental API . Assert arguments match postcondition
- Parameters:
kw_args – dictionary of arguments that will be passed to command callback function.
- Returns:
True if arguments are consistent
- error_message()
Experimental API . Appropriate error message if check fails.
- Returns:
error message
- class RepeatOf(annotation)
Bases:
Annotation
Annotation for keyword options that can occur multiple times.
RepeatOf(annotation) -> annotation
Option values are put in list even if option occurs only once.
- class RestOfLine(name=None, url=None, html_name=None)
Bases:
Annotation
Return the rest of the line up to a semicolon
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class SameSize(name1, name2)
Bases:
Postcondition
Postcondition check for same size arguments
SameSize(name1, name2) -> a SameSize object
- Parameters:
name1 – name of first argument to check
name2 – name of second argument to check
- check(kw_args)
Experimental API . Assert arguments match postcondition
- Parameters:
kw_args – dictionary of arguments that will be passed to command callback function.
- Returns:
True if arguments are consistent
- error_message()
Experimental API . Appropriate error message if check fails.
- Returns:
error message
- class SaveFileNameArg(name=None, url=None, html_name=None)
Bases:
FileNameArg
Annotation for a file to save
- classmethod parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- class SaveFolderNameArg(name=None, url=None, html_name=None)
Bases:
FileNameArg
Annotation for a folder to save to
- classmethod parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- class SetOf(annotation, min_size=None, max_size=None, name=None, url=None, prefix=None)
Bases:
Aggregate
Annotation for sets of a single type
SetOf(annotation, min_size=None, max_size=None) -> annotation
- add_to(container, value)
Experimental API . Add to add an element to the container
- Parameters:
container – the container to add elements to
element – the element to add to the container
- Returns:
None for mutable containers, or a new container if immutable.
- constructor
alias of
set
- class StringArg(name=None, url=None, html_name=None)
Bases:
Annotation
Annotation for text (a word or quoted)
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class SurfaceArg(name=None, url=None, html_name=None)
Bases:
SurfacesArg
Parse command surfaces specifier
- classmethod parse(text, session)
Experimental API . Parse text and return an atomspec parse tree
- class SurfacesArg(name=None, url=None, html_name=None)
Bases:
ModelsArg
Parse command surfaces specifier
- classmethod parse(text, session)
Experimental API . Parse text and return an atomspec parse tree
- class TopModelsArg(name=None, url=None, html_name=None)
Bases:
AtomSpecArg
Parse command models specifier
- classmethod parse(text, session)
Experimental API . Parse text and return an atomspec parse tree
- classmethod unparse(tmodels, session)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- class TupleOf(annotation, size, name=None, url=None)
Bases:
Aggregate
Annotation for tuples of a single type
TupleOf(annotation, size) -> annotation
- add_to(container, value)
Experimental API . Add to add an element to the container
- Parameters:
container – the container to add elements to
element – the element to add to the container
- Returns:
None for mutable containers, or a new container if immutable.
- constructor
alias of
tuple
- class WholeRestOfLine(name=None, url=None, html_name=None)
Bases:
Annotation
Return the whole rest of the line including semicolons
- static parse(text, session)
Supported API . Convert text to appropriate type.
- Parameters:
text – command line text to parse
session – for session-dependent data types
- Returns:
3-tuple with the converted value, consumed text (possibly altered with expanded abbreviations), and the remaining unconsumed text
- Raises:
AnnotationError – if unable to convert text
The leading space in text must already be removed. It is up to the particular annotation to support abbreviations.
Empty text should raise a ValueError or AnnotationError exception (the exceptions being
NoArg
andEmptyArg
).
- static unparse(value, session=None)
Experimental API . Convert value to string that can parsed back into value
- Parameters:
value – the value to convert
session – requried for session-dependent data types
- Returns:
string version of the value
The return value should be what would be typed if the value were given on the command line.
- as_parser(annotation)
Experimental API . Deprecated API. Use make_converter() instead
- command_function(name, no_aliases=False, *, registry=None)
Experimental API . Return callable for given command name
- Parameters:
name – the name of the command
no_aliases – True if aliases should not be considered.
- Returns:
the callable that implements the command
- command_url(name, no_aliases=False, *, registry=None)
Experimental API . Return help URL for given command name
- Parameters:
name – the name of the command
no_aliases – True if aliases should not be considered.
- Returns:
the URL registered with the command
- commas(text_seq, conjunction='or')
Experimental API . Return comma separated list of words
- Parameters:
text_seq – a sequence of text strings
conjunction – a word to put for last item (default ‘or’)
- create_alias(name, text, *, user=False, logger=None, url=None, registry=None)
Experimental API . Create command alias
- Parameters:
name – name of the alias
text – text of the alias
user – boolean, true if user created alias
logger – optional logger
- delay_registration(name, proxy_function, logger=None)
Experimental API . delay registering a named command until needed
- Parameters:
proxy_function – the function to call if command is used
logger – optional logger
The proxy function should explicitly reregister the command or register subcommands and return nothing.
Example:
from chimerax.core.commands import cli def lazy_reg(): import module cli.register('cmd subcmd1', module.subcmd1_desc, module.subcmd1) cli.register('cmd subcmd2', module.subcmd2_desc, module.subcmd2) cli.delay_registration('cmd', lazy_reg)
- deregister(name, *, is_user_alias=False, registry=None)
Experimental API . Remove existing command and subcommands
- Parameters:
name – the name of the command
If the command was an alias, the previous version is restored
- discard_article(text)
Experimental API . remove leading article from text
- dq_repr(obj)
Experimental API . Like repr, but use double quotes
- expand_alias(name, *, registry=None)
Experimental API . Return text of named alias
- Parameters:
name – name of the alias
- is_python_keyword()
Experimental API . x.__contains__(y) <==> y in x.
- list_aliases(all=False, logger=None)
Experimental API . List all aliases
- Parameters:
all – if True, then list all aliases, not just user ones
Return in depth-first order.
- make_converter(annotation)
Supported API . Use any annotation to convert text to annotation’s type
- Parameters:
annotation – the annotation to use
- Raises:
AnnotationError – if unable to convert text
For example:
from chimerax.core.commands import make_converter, ColorArg convert_to_color = make_converter(ColorArg) color = convert_to_color(session, “red”)
- next_token(text, convert=False)
Experimental API . Extract next, optionally quoted, token from given text.
- Parameters:
text – text to parse without leading whitespace
convert – convert escape sequences to characters
- Returns:
a 3-tuple of first argument in text, the actual text used, and the rest of the text.
If the token is quoted, then the text between the quotes is returned. End quotes must be followed by whitespace or the end of the line. If convert is True, then escape sequences in the token are converted to the actual character. The escape sequences are the same as Python’s as documented in Literals.
- ordinal(i)
Experimental API . Return ordinal number name of number
- plural_form(things, word, plural=None)
Experimental API . Return plural of word based on length of sequence
- Parameters:
things – a sequence of objects or an integer
word – word to form the plural of
plural – optional explicit plural of word, otherwise best guess
- plural_of(word)
Experimental API . Return best guess of the American English plural of the word
- Parameters:
word – the word to form the plural version
The guess is rudimentary, e.g., it does not handle changing “leaf” to “leaves”. So in general, use the
plural_form()
function and explicitly give the plural.
- quote_if_necessary(s, additional_special_map={})
Experimental API . quote a string
So
StringArg
treats it like a single value
- quote_path_if_necessary(path)
Experimental API . quote a string
So a
FileNameArg
(or subclass) treats it like a singe value. String escape sequences are not recognized in paths, so there no way to quote a path so that both single and double quotes that would need quoting.
- register(name, cmd_desc=(), function=None, *, logger=None, registry=None)
Experimental API . register function that implements command
- Parameters:
- Return type:
If the function is None, then it assumed that
register()
is being used as a decorator.registry is a RegisteredCommandInfo instance and is only used if you want your own separate registry of commands, to be parsed/executed on text you provide. One usage scenario is a set of “subcommands” organized under an “umbrella” command, e.g.:
sequence viewer <viewer-id> command-to-viewer
The ‘command-to-viewer’ commands could have their own separate registry.
To delay introspecting the function until it is actually used, register using the
delay_registration()
function.
- registered_commands(multiword=False, _start=None)
Experimental API . Return a sorted list of the currently registered commands
- remove_alias(name=None, user=False, logger=None, *, registry=None)
Experimental API . Remove command alias
- Parameters:
name – name of the alias
user – boolean, true if user created alias
If no name is given, then all user generated aliases are removed.
- unescape(text)
Experimental API . Replace backslash escape sequences with actual character.
- Parameters:
text – the input text
- Returns:
the processed text
Follows Python’s string literal syntax for escape sequences.
- unescape_with_index_map(text)
Experimental API . Replace backslash escape sequences with actual character.
- Parameters:
text – the input text
- Returns:
the processed text and index map from processed to input text
Follows Python’s string literal syntax for escape sequences.
- user_kw(kw_name)
Experimental API . Return user version of a keyword argument name.
atomspec: atom specifier cli annotation and evaluation¶
The ‘atomspec’ module provides two classes:
AtomSpecArg : command line argument annotation class.
AtomSpec : atom specifier class.
AtomSpecArg is a cli type annotation and is used to describe an argument of a function that is registered with the cli module. When the registered function is called, the argument corresponding to the AtomSpecArg is an instance of AtomSpec, which contains a parsed version of the input atom specifier. The model elements (atoms, bonds, models, etc) that match an AtomSpec may be found by calling the ‘evaluate’ method which returns an instance of Objects. Each type of model elements may be accessed as an attribute of the Objects instance.
Selectors¶
A (name, function) pair may be registered as a ‘selector’ in an atom specifier. The selectors may either be global (e.g., chemical groups) or session-specific (e.g., active site). The selector name may appear wherever a model, residue or atom string does. The selector function is called when the atom specifier is evaluated and is expected to fill in an Objects instance.
Example
Here is an example of a function that may be registered with cli:
from chimerax.core.commands import cli, atomspec
def move(session, by, modelspec=None):
if modelspec is None:
modelspec = atomspec.everything(session)
spec = modelspec.evaluate(session)
import numpy
by_vector = numpy.array(by)
from chimerax.geometry import place
translation = place.translation(by_vector)
for m in spec.models:
m.position = translation * m.position
move_desc = cli.CmdDesc(required=[("by", cli.Float3Arg)],
optional=[("modelspec", atomspec.AtomSpecArg)])
Notes
AtomSpecArg arguments should always be optional because not providing an atom specifier is the same as choosing all atoms.
- class AtomSpec(operator, left_spec, right_spec, *, add_implied=True)¶
Bases:
object
AtomSpec instances store and evaluate atom specifiers.
An AtomSpec instance, returned by AtomSpecArg arguments in cli command functions, keeps track of an atom specifier. When evaluated, the model elements that match the specifier are returned.
- evaluate(session, models=None, *, order_implicit_atoms=False, add_implied=None, **kw)¶
Experimental API . Return results of evaluating atom specifier for given models.
- Parameters:
session (chimerax.core.session.Session instance) – The session in which to evaluate atom specifier.
models (list of chimerax.core.models.Model instances) – Defaults to None, which uses all models in ‘session’.
order_implicit_atoms (whether to order atoms that aren't) – explicitly specified (e.g. “:5”) [which can be costly]
**kw (keyword arguments) – If ‘models’ is None, ‘kw’ is passed through to call to ‘session.models.list’ to generate the model list.
- Returns:
Instance containing data (atoms, bonds, etc) that match this atom specifier.
- Return type:
Objects instance
- class AtomSpecArg(name=None, url=None, html_name=None)¶
Bases:
Annotation
Command line type annotation for atom specifiers.
See cli documentation for details on type annotations.
- classmethod parse(text, session)¶
Experimental API . Parse text and return an atomspec parse tree
- all_objects(session)¶
Experimental API . Return Objects that matches everything.
- deregister_selector(name, logger=None)¶
Experimental API . Deregister a name as an atom specifier selector.
- Parameters:
name (str) – Previously registered selector name.
logger (instance of chimerax.core.logger.Logger) – Current logger.
- Raises:
KeyError – If name is not registered.
- everything(session)¶
Experimental API . Return AtomSpec that matches everything.
- Parameters:
session (instance of chimerax.core.session.Session) – Session in which the name may be used. If None, name is global.
- Returns:
An AtomSpec instance that matches everything in session.
- Return type:
AtomSpec instance
- get_selector(name)¶
Experimental API . Return value associated with registered selector name.
- Parameters:
name (str) – Previously registered selector name.
- Returns:
Callable object if name was registered; None, if not.
- Return type:
Callable object, Objects instance, or None.
- get_selector_description(name, session)¶
Experimental API . Return description for selector.
- Parameters:
session (instance of chimerax.core.session.Session) – Session in which the name may be used. If None, name is global.
name (str) – Previously registered selector name.
- Returns:
Description of selector. Registered description is used when available; otherwise, description is generated from the selector value.
- Return type:
string
- is_selector_atomic(name)¶
Experimental API . Return whether selector may select any atoms.
- Parameters:
name (str) – Previously registered selector name.
- Returns:
Whether selector name may select any atoms.
- Return type:
Boolean
- is_selector_user_defined(name)¶
Experimental API . Return whether selector name is user-defined.
- Parameters:
name (str) – Previously registered selector name.
- Returns:
Whether selector name is user-defined.
- Return type:
Boolean
- list_selectors()¶
Experimental API . Return a list of all registered selector names.
- Returns:
Iterator that yields registered selector names.
- Return type:
iterator yielding str
- register_selector(name, value, logger, *, user=False, desc=None, atomic=True)¶
Experimental API . Register a (name, value) pair as an atom specifier selector.
- Parameters:
name (str) – Selector name, preferably without whitespace.
value (callable object or instance of Objects) – Selector value. If a callable object, called as ‘value(session, models, results)’ where ‘models’ are chimerax.core.models.Model instances and ‘results’ is an Objects instance; the callable is expected to add selected items to ‘results’. If an Objects instance, items in value are merged with already selected items.
logger (instance of chimerax.core.logger.Logger) – Current logger.
user (boolean) – Boolean value indicating whether name is considered user-defined or not.
desc (string) – Selector description. Returned by get_selector_description(). If not supplied, a generic description will be generated.
atomic (boolean) – Boolean value indicating atoms may be selected using selector. Non-atomic selectors will not appear in Basic Actions tool.
- run(session, text, *, log=True, downgrade_errors=False, return_json=False, return_list=False)¶
Experimental API . execute a textual command
- Parameters:
text (string) – The text of the command to execute.
log (bool) – Print the command text to the reply log.
downgrade_errors (bool) – True if errors in the command should be logged as informational.
return_json (bool) – If True, underlying commands that themselves support a ‘return_json’ keyword should return a JSONResult object.
return_list (bool) – True if a list should be returned even if only one command is executed
- runscript(session, script_file, *, args=None)¶
Experimental API . Execute a Python or ChimeraX command script with arguments
- Parameters:
script_file (string) – Path to Python script file
args (string) – Optional string containing the arguments to pass to the script