Source code for sphinx_gmt.gmtplot

"""
A directive for including a GMT plot in a Sphinx document.

Options
-------

The ``gmtplot`` directive supports the following options:

show-code
    Whether to show the source code. The default can be changed by the
    ``gmtplot_show_code`` variable in ``conf.py``.

language
    Specify the language of the source code: either "bash" or "python".

caption
    Caption of the rendered figure.

Additionally, this directive also supports options of the standard ``figure``
and ``literalinclude`` directives.

Configuration options
---------------------

The following options can be set in ``conf.py`` and will apply globally:

gmtplot_show_code
    Default value for the ``show-code`` option. Default is ``True``.

gmtplot_basedir
    Base directory, to which ``gmtplot`` file names are relative to. If None or
    empty, file names are relative to the directory where the file containing the
    directive is. However, if it is absolute (starting with ``/``), it is relative
    to the top source directory. Default is ``None``.

gmtplot_figure_align
    The figure alignment. Default is ``"center"``.

gmtplot_gmt_config
    A dict of GMT settings that are applied to all GMT scripts.
    Default is ``{"GMT_GRAPHICS_FORMAT": "ps"}``.

"""

import ast
import os
import shutil
import subprocess
import sys
import tempfile
import textwrap
from contextlib import contextmanager
from pathlib import Path

import jinja2
from docutils.parsers.rst import Directive, directives
from sphinx.util import md5

TEMPLATE = """
{%- if show_code -%}
.. literalinclude:: {{ code }}
    {% for option in code_opts -%}
    {{ option }}
    {% endfor %}
{%- else %}
:download:`Source Code <{{ code }}>`
{%- endif %}

.. figure:: {{ image }}
    :name: {{ label }}
    {% for option in image_opts -%}
    {{ option }}
    {% endfor %}

    {{ caption }}

"""


def _option_language(arg):
    """
    Check language option.
    """
    return directives.choice(arg, ("bash", "python"))


def _option_boolean(arg):
    """
    Check boolean options.
    """
    if not arg or not arg.strip():  # no argument given, assume used as a flag
        return True
    if arg.strip().lower() in ("no", "0", "false"):
        return False
    if arg.strip().lower() in ("yes", "1", "true"):
        return True
    raise ValueError('f"{arg}" unknown boolean')


def _option_align(arg):
    """
    Check align option.
    """
    return directives.choice(
        arg, ("top", "middle", "bottom", "left", "center", "right")
    )


def _updated_gmt_datadir(code_dir):
    """
    Add the code's current directory to evirionment variable GMT_DATADIR
    so that script can access its data files.
    """
    if os.environ.get("GMT_DATADIR") is not None:
        sep = ";" if sys.platform == "win32" else ":"
        return f"{sep}".join([str(code_dir), os.environ["GMT_DATADIR"]])
    return str(code_dir)


[docs]@contextmanager def environ(env): """ Temporarily set environment variables inside the context manager and fully restore previous environment afterwards. """ original_env = {key: os.getenv(key) for key in env} os.environ.update(env) try: yield finally: for key, value in original_env.items(): if value is None: del os.environ[key] else: os.environ[key] = value
def _write_gmt_config(gmt_config, cwd): """ Write GMT settings to a gmt.conf file in the current directory. """ if not gmt_config: return with open(Path(cwd, "gmt.conf"), "w", encoding="utf-8") as fconf: for key, value in gmt_config.items(): fconf.write(f"{key} = {value}") def _search_images(cwd): # pylint: disable=no-else-return,no-else-raise """ Search images in PNG and PDF format in a specified directory. If .png and .pdf files are not found and .ps file is found, then convert .ps file to PNG and PDF format. """ cwd = Path(cwd) png_images = list(cwd.glob("*.png")) if len(png_images) > 1: raise ValueError("More than one figure generated in one GMT plot.") elif len(png_images) == 1: pdf_images = list(cwd.glob("*.pdf")) if len(pdf_images) == 1: return [png_images[0], pdf_images[0]] else: return [png_images[0]] else: # no PNG found ps_images = list(cwd.glob("*.ps")) if len(ps_images) > 1: raise ValueError("More than one figure generated in one GMT plot.") elif len(ps_images) == 1: # PS found cmd = "gmt psconvert -A -P -T{} {}" subprocess.run(cmd.format("g", ps_images[0]), shell=True, check=False) subprocess.run(cmd.format("f", ps_images[0]), shell=True, check=False) png_images = list(cwd.glob("*.png")) pdf_images = list(cwd.glob("*.pdf")) if len(png_images) == 1 and len(pdf_images) == 1: return [png_images[0], pdf_images[0]] else: return [] else: # No PNG and PS found return []
[docs]def eval_bash(code, code_dir, output_dir, output_base, config=None): """ Execute a multi-line block of bash code and copy the generated image files to specified output directory. """ with environ( {"GMT_END_SHOW": "off", "GMT_DATADIR": _updated_gmt_datadir(code_dir)} ), tempfile.TemporaryDirectory() as tmpdir: Path(tmpdir, "gmtplot-script.sh").write_text(code, encoding="utf-8") if config.gmtplot_gmt_config: _write_gmt_config(config.gmtplot_gmt_config, cwd=tmpdir) proc = subprocess.run( ["bash", "-e", Path(tmpdir, "gmtplot-script.sh")], check=False, cwd=tmpdir, stdout=subprocess.PIPE, stderr=subprocess.PIPE, ) if proc.returncode != 0: raise RuntimeError( "\nGMT bash failed:\n" f"{code}" f"STDOUT: {proc.stdout.decode('utf-8')}" f"STDERR: {proc.stderr.decode('utf-8')}" ) for image in _search_images(tmpdir): shutil.move(image, Path(output_dir, output_base).with_suffix(image.suffix)) return f"{output_base}.*"
class _CatchDisplay: "Class to temporarily catch sys.displayhook" # pylint: disable=too-few-public-methods # pylint: disable=attribute-defined-outside-init def __init__(self): self.output = None def __enter__(self): self.old_hook = sys.displayhook sys.displayhook = self return self def __exit__(self, dtype, value, traceback): sys.displayhook = self.old_hook # Returning False will cause exceptions to propagate return False def __call__(self, output): self.output = output
[docs]def eval_python( code, code_dir, output_dir, output_base, filename="<string>", config=None ): # pylint: disable=exec-used,too-many-arguments """ Execute a multi-line block of Python code and copy the generated image files to specified output directory. """ tree = ast.parse(code, filename="<ast>", mode="exec") if ( isinstance(tree.body[-1], ast.Expr) and tree.body[-1].value.func.attr == "show" ): # last statement is `fig.show()` in pygmt to_exec, to_eval = tree.body[:-1], tree.body[-1:] else: to_exec, to_eval = tree.body, [] cwd = os.getcwd() with environ( {"GMT_END_SHOW": "off", "GMT_DATADIR": _updated_gmt_datadir(code_dir)} ), tempfile.TemporaryDirectory() as tmpdir: os.chdir(tmpdir) if config.gmtplot_gmt_config: _write_gmt_config(config.gmtplot_gmt_config, cwd=".") for node in to_exec: exec( compile( ast.Module([node], type_ignores=[]), filename=filename, mode="exec" ) ) images = _search_images(tmpdir) if images: for image in images: shutil.move( image, Path(output_dir, output_base).with_suffix(image.suffix) ) else: catch_display = _CatchDisplay() with catch_display: for node in to_eval: exec( compile( ast.Interactive([node]), filename=filename, mode="single" ) ) Path(output_dir, output_base).with_suffix(".png").write_bytes( catch_display.output.data ) os.chdir(cwd) return f"{output_base}.*"
[docs]def render_figure(code, code_dir, language, output_dir, output_base, config=None): """ Run a GMT code and save the images in *output_dir* with file names derived from *output_base*. """ # pylint: disable=too-many-arguments if language == "bash": figname = eval_bash(code, code_dir, output_dir, output_base, config=config) elif language == "python": figname = eval_python(code, code_dir, output_dir, output_base, config=config) return figname
[docs]def guess_language(filename): """ Guess language from suffix of the script. """ suffix = Path(filename).suffix if suffix in [".sh", ".bash"]: return "bash" if suffix == ".py": return "python" raise ValueError(f"Cannot guess language for file {filename}.")
[docs]def get_suffix_from_language(language): """ Determine suffix from language. """ if language == "bash": return "sh" if language == "python": return "py" raise ValueError(f"Unrecognized language {language}.")
[docs]class GMTPlotDirective(Directive): """ The gmtplot directive implementation. """ has_content = True required_arguments = 0 optional_arguments = 1 final_argument_whitespace = False # options for the literalinclude directive options_code = { "dedent": int, "linenos": directives.flag, "lineno-start": int, "lineno-match": directives.flag, "tab-width": int, "language": _option_language, "encoding": directives.encoding, "lines": directives.unchanged_required, "start-after": directives.unchanged_required, "end-before": directives.unchanged_required, "start-at": directives.unchanged_required, "end-at": directives.unchanged_required, "prepend": directives.unchanged_required, "append": directives.unchanged_required, "emphasize-lines": directives.unchanged_required, "name": directives.unchanged, } # options for the figure directive options_figure = { "alt": directives.unchanged, "height": directives.length_or_unitless, "width": directives.length_or_percentage_or_unitless, "scale": directives.nonnegative_int, "align": _option_align, "class": directives.class_option, } # options for the gmtplot directive option_spec = { "show-code": _option_boolean, "caption": directives.unchanged, **options_code, **options_figure, } def run(self): # pylint: disable=too-many-locals document = self.state_machine.document env = self.state_machine.document.settings.env config = self.state_machine.document.settings.env.config # set options to default values if not specified self.options.setdefault("show-code", config.gmtplot_show_code) self.options.setdefault("align", config.gmtplot_figure_align) # Get the name of the rst source file we are currently processing rst_file = Path(document["source"]) # current working directory of the rst source file cwd = rst_file.parent if self.arguments: # load codes from a file # Guess language from suffix of the script if "language" not in self.options: self.options["language"] = guess_language(self.arguments[0]) # Get absolute path of the script if config.gmtplot_basedir: # relative to gmtplot_basedir code_file = Path( env.app.srcdir, config.gmtplot_basedir, self.arguments[0] ) elif self.arguments[0].startswith("/"): # relative to source directory code_file = Path(env.app.srcdir, self.arguments[0][1:]) else: # relative to current rst file's path code_file = Path(cwd, self.arguments[0]) code_basedir = code_file.absolute().parent code = code_file.read_text(encoding="utf-8") # If there is content, it will be passed as a caption. caption = "\n".join(self.content) else: # inline codes if "language" not in self.options: self.options["language"] = config.highlight_language code_basedir = cwd code = textwrap.dedent("\n".join(map(str, self.content))) caption = self.options["caption"] if "caption" in self.options else "" # use the md5sum value of the code as the basename of script and image files output_base = md5(code.encode()).hexdigest() # determine unique code filename under current working directory suffix = get_suffix_from_language(self.options["language"]) code_file = Path(cwd, f"{output_base}.{suffix}") code_opts = "" if self.options["show-code"]: code_opts = [] for key, val in self.options.items(): if key == "linenos": code_opts.append(f":{key}:") elif key in self.options_code: code_opts.append(f":{key}: {val}") image_opts = [ f":{key}: {val}" for key, val in self.options.items() if key in self.options_figure ] # builddir: where to place output files (temporarily) builddir = Path(env.app.doctreedir).parent / "gmtplot_directive" # determine how to link to files in builddir from the RST file # use os.path.relpath rather than relative_to! builddir_link = "/" / Path("/", os.path.relpath(str(builddir), env.app.srcdir)) # copy script to builddir builddir.mkdir(parents=True, exist_ok=True) Path(builddir, code_file.name).write_text(code, encoding="utf-8") # make figures image = render_figure( code, code_basedir, self.options["language"], builddir, output_base, config ) gmtplot_block = ( jinja2.Template(TEMPLATE) .render( label="gmtplot-" + output_base, show_code=self.options["show-code"], code=builddir_link / code_file.name, code_opts=code_opts, image=builddir_link / image, image_opts=image_opts, caption=caption, ) .split("\n") ) gmtplot_block.extend("\n") self.state_machine.insert_input(gmtplot_block, source=str(rst_file)) return []
[docs]def setup(app): """ Add the gmtplot directive to the sphinx app. """ setup.app = app setup.config = app.config setup.confdir = app.confdir app.add_directive("gmtplot", GMTPlotDirective) app.add_config_value("gmtplot_basedir", None, True) app.add_config_value("gmtplot_show_code", True, True) app.add_config_value("gmtplot_figure_align", "center", True) app.add_config_value("gmtplot_gmt_config", {"GMT_GRAPHICS_FORMAT": "ps"}, True) metadata = { "version": "0.3.0", "parallel_read_safe": True, "parallel_write_safe": True, } return metadata