def echo():
"""Use in a `with` block to draw some code on the app, then execute it.
Example
-------
>>> with st.echo():
>>> st.write('This code will be printed')
"""
code = empty() # noqa: F821
try:
frame = _traceback.extract_stack()[-3]
filename, start_line = frame.filename, frame.lineno
yield
frame = _traceback.extract_stack()[-3]
end_line = frame.lineno
lines_to_display = [] # type: List[str]
with _source_util.open_python_file(filename) as source_file:
source_lines = source_file.readlines()
lines_to_display.extend(source_lines[start_line:end_line])
match = _SPACES_RE.match(lines_to_display[0])
initial_spaces = match.end() if match else 0
for line in source_lines[end_line:]:
match = _SPACES_RE.match(line)
indentation = match.end() if match else 0
# The != 1 is because we want to allow '\n' between sections.
if indentation != 1 and indentation < initial_spaces:
break
lines_to_display.append(line)
line_to_display = _textwrap.dedent("".join(lines_to_display))
code.code(line_to_display, "python")
except FileNotFoundError as err:
code.warning("Unable to display code. %s" % err)
def echo(code_location="above"):
"""Use in a `with` block to draw some code on the app, then execute it.
Parameters
----------
code_location : "above" or "below"
Whether to show the echoed code before or after the results of the
executed code block.
Example
-------
>>> with st.echo():
>>> st.write('This code will be printed')
"""
if code_location == "below":
show_code = code
show_warning = warning
else:
placeholder = empty()
show_code = placeholder.code
show_warning = placeholder.warning
try:
frame = _traceback.extract_stack()[-3]
filename, start_line = frame.filename, frame.lineno
yield
frame = _traceback.extract_stack()[-3]
end_line = frame.lineno
lines_to_display = [] # type: List[str]
with _source_util.open_python_file(filename) as source_file:
source_lines = source_file.readlines()
lines_to_display.extend(source_lines[start_line:end_line])
match = _SPACES_RE.match(lines_to_display[0])
initial_spaces = match.end() if match else 0
for line in source_lines[end_line:]:
match = _SPACES_RE.match(line)
indentation = match.end() if match else 0
# The != 1 is because we want to allow '\n' between sections.
if indentation != 1 and indentation < initial_spaces:
break
lines_to_display.append(line)
line_to_display = _textwrap.dedent("".join(lines_to_display))
show_code(line_to_display, "python")
except FileNotFoundError as err:
show_warning("Unable to display code. %s" % err)
def end_code_block(display=True):
"""Ends the current code block and sends it to streamlit output.
Args:
display: whether to show this code block in the output
"""
global _current_end_line
global _space_for_code
frame = traceback.extract_stack()[
-2] # stack[-1] would be this frame itself
# stack[-2] is the frame in the user's "notebook" calling us
# (as long as the user is calling us directly)
filename, lineno = frame.filename, frame.lineno
with open_python_file(filename) as source_file:
source_lines = source_file.readlines()
lines_to_display = source_lines[_current_end_line:(
lineno - 1)] # `lineno-1` means we skip showing the call to us
_current_end_line = lineno
if display:
_space_for_code.code(''.join(lines_to_display), 'python')
_space_for_code = st.empty()
def end_code_block(display=True):
"""Ends the current code block and sends it to streamlit output.
Keyword Arguments:
display: whether to show this code block in the output
"""
global _CURRENT_END_LINE # pylint: disable=global-statement
global _SPACE_FOR_CODE # pylint: disable=global-statement
frame = traceback.extract_stack()[
-2] # stack[-1] would be this frame itself
# stack[-2] is the frame in the user's "notebook" calling us
# (as long as the user is calling us directly)
filename, lineno = frame.filename, frame.lineno
filename = awesome_streamlit_hack(filename)
with open_python_file(filename) as source_file:
source_lines = source_file.readlines()
# `lineno-1` means we skip showing the call to us
lines_to_display = source_lines[_CURRENT_END_LINE:(lineno - 1)]
_CURRENT_END_LINE = lineno
if display:
_SPACE_FOR_CODE.code("".join(lines_to_display), "python")
_SPACE_FOR_CODE = st.empty()
def echo():
"""Use in a `with` block to draw some code on the app, then execute it.
Example
-------
>>> with st.echo():
>>> st.write('This code will be printed')
"""
code = empty() # noqa: F821
try:
frame = _traceback.extract_stack()[-3]
if _is_running_py3():
filename, start_line = frame.filename, frame.lineno
else:
filename, start_line = frame[:2]
yield
frame = _traceback.extract_stack()[-3]
if _is_running_py3():
end_line = frame.lineno
else:
end_line = frame[1]
lines_to_display = []
with _source_util.open_python_file(filename) as source_file:
source_lines = source_file.readlines()
lines_to_display.extend(source_lines[start_line:end_line])
initial_spaces = _SPACES_RE.match(lines_to_display[0]).end()
for line in source_lines[end_line:]:
if _SPACES_RE.match(line).end() < initial_spaces:
break
lines_to_display.append(line)
lines_to_display = _textwrap.dedent("".join(lines_to_display))
code.code(lines_to_display, "python")
except FileNotFoundError as err: # noqa: F821
code.warning("Unable to display code. %s" % err)
def _run_script(self, rerun_data):
"""Run our script.
Parameters
----------
rerun_data: RerunData
The RerunData to use.
"""
assert self._is_in_script_thread()
LOGGER.debug("Running script %s", rerun_data)
# Reset DeltaGenerators, widgets, media files.
media_file_manager.clear_session_files()
ctx = get_report_ctx()
if ctx is None:
# This should never be possible on the script_runner thread.
raise RuntimeError(
"ScriptRunner thread has a null ReportContext. Something has gone very wrong!"
)
ctx.reset(query_string=rerun_data.query_string)
self.on_event.send(ScriptRunnerEvent.SCRIPT_STARTED)
# Compile the script. Any errors thrown here will be surfaced
# to the user via a modal dialog in the frontend, and won't result
# in their previous report disappearing.
try:
with source_util.open_python_file(self._report.script_path) as f:
filebody = f.read()
if config.get_option("runner.magicEnabled"):
filebody = magic.add_magic(filebody, self._report.script_path)
code = compile(
filebody,
# Pass in the file path so it can show up in exceptions.
self._report.script_path,
# We're compiling entire blocks of Python, so we need "exec"
# mode (as opposed to "eval" or "single").
mode="exec",
# Don't inherit any flags or "future" statements.
flags=0,
dont_inherit=1,
# Use the default optimization options.
optimize=-1,
)
except BaseException as e:
# We got a compile error. Send an error event and bail immediately.
LOGGER.debug("Fatal script error: %s" % e)
self.on_event.send(
ScriptRunnerEvent.SCRIPT_STOPPED_WITH_COMPILE_ERROR,
exception=e)
return
# If we get here, we've successfully compiled our script. The next step
# is to run it. Errors thrown during execution will be shown to the
# user as ExceptionElements.
# Update the Widget object with the new widget_states.
# (The ReportContext has a reference to this object, so we just update it in-place)
if rerun_data.widget_states is not None:
self._widgets.set_state(rerun_data.widget_states)
if config.get_option("runner.installTracer"):
self._install_tracer()
# This will be set to a RerunData instance if our execution
# is interrupted by a RerunException.
rerun_with_data = None
try:
# Create fake module. This gives us a name global namespace to
# execute the code in.
module = _new_module("__main__")
# Install the fake module as the __main__ module. This allows
# the pickle module to work inside the user's code, since it now
# can know the module where the pickled objects stem from.
# IMPORTANT: This means we can't use "if __name__ == '__main__'" in
# our code, as it will point to the wrong module!!!
sys.modules["__main__"] = module
# Add special variables to the module's globals dict.
# Note: The following is a requirement for the CodeHasher to
# work correctly. The CodeHasher is scoped to
# files contained in the directory of __main__.__file__, which we
# assume is the main script directory.
module.__dict__["__file__"] = self._report.script_path
with modified_sys_path(self._report), self._set_execing_flag():
exec(code, module.__dict__)
except RerunException as e:
rerun_with_data = e.rerun_data
except StopException:
pass
except BaseException as e:
handle_uncaught_app_exception(e)
finally:
self._widgets.reset_triggers()
self._widgets.cull_nonexistent(ctx.widget_ids_this_run.items())
self.on_event.send(ScriptRunnerEvent.SCRIPT_STOPPED_WITH_SUCCESS)
# delete expired files now that the script has run and files in use
# are marked as active
media_file_manager.del_expired_files()
# Use _log_if_error() to make sure we never ever ever stop running the
# script without meaning to.
_log_if_error(_clean_problem_modules)
if rerun_with_data is not None:
self._run_script(rerun_with_data)
def echo(code_location="above"):
"""Use in a `with` block to draw some code on the app, then execute it.
Parameters
----------
code_location : "above" or "below"
Whether to show the echoed code before or after the results of the
executed code block.
Example
-------
>>> with st.echo():
>>> st.write('This code will be printed')
"""
from streamlit import code, warning, empty, source_util
if code_location == "below":
show_code = code
show_warning = warning
else:
placeholder = empty()
show_code = placeholder.code
show_warning = placeholder.warning
try:
# Get stack frame *before* running the echoed code. The frame's
# line number will point to the `st.echo` statement we're running.
frame = traceback.extract_stack()[-3]
filename, start_line = frame.filename, frame.lineno
# Read the file containing the source code of the echoed statement.
with source_util.open_python_file(filename) as source_file:
source_lines = source_file.readlines()
# Get the indent of the first line in the echo block, skipping over any
# empty lines.
initial_indent = _get_initial_indent(source_lines[start_line:])
# Iterate over the remaining lines in the source file
# until we find one that's indented less than the rest of the
# block. That's our end line.
#
# Note that this is *not* a perfect strategy, because
# de-denting is not guaranteed to signal "end of block". (A
# triple-quoted string might be dedented but still in the
# echo block, for example.)
# TODO: rewrite this to parse the AST to get the *actual* end of the block.
lines_to_display: List[str] = []
for line in source_lines[start_line:]:
indent = _get_indent(line)
if indent is not None and indent < initial_indent:
break
lines_to_display.append(line)
code_string = textwrap.dedent("".join(lines_to_display))
# Run the echoed code...
yield
# And draw the code string to the app!
show_code(code_string, "python")
except FileNotFoundError as err:
show_warning("Unable to display code. %s" % err)
def _run_script(self, rerun_data: RerunData) -> None:
"""Run our script.
Parameters
----------
rerun_data: RerunData
The RerunData to use.
"""
assert self._is_in_script_thread()
LOGGER.debug("Running script %s", rerun_data)
# Reset DeltaGenerators, widgets, media files.
in_memory_file_manager.clear_session_files()
ctx = self._get_script_run_ctx()
ctx.reset(query_string=rerun_data.query_string)
self.on_event.send(ScriptRunnerEvent.SCRIPT_STARTED)
# Compile the script. Any errors thrown here will be surfaced
# to the user via a modal dialog in the frontend, and won't result
# in their previous script elements disappearing.
try:
with source_util.open_python_file(
self._session_data.script_path) as f:
filebody = f.read()
if config.get_option("runner.magicEnabled"):
filebody = magic.add_magic(filebody,
self._session_data.script_path)
code = compile(
filebody,
# Pass in the file path so it can show up in exceptions.
self._session_data.script_path,
# We're compiling entire blocks of Python, so we need "exec"
# mode (as opposed to "eval" or "single").
mode="exec",
# Don't inherit any flags or "future" statements.
flags=0,
dont_inherit=1,
# Use the default optimization options.
optimize=-1,
)
except BaseException as e:
# We got a compile error. Send an error event and bail immediately.
LOGGER.debug("Fatal script error: %s" % e)
self._session_state[SCRIPT_RUN_WITHOUT_ERRORS_KEY] = False
self.on_event.send(
ScriptRunnerEvent.SCRIPT_STOPPED_WITH_COMPILE_ERROR,
exception=e)
return
# If we get here, we've successfully compiled our script. The next step
# is to run it. Errors thrown during execution will be shown to the
# user as ExceptionElements.
if config.get_option("runner.installTracer"):
self._install_tracer()
# This will be set to a RerunData instance if our execution
# is interrupted by a RerunException.
rerun_with_data = None
try:
# Create fake module. This gives us a name global namespace to
# execute the code in.
module = _new_module("__main__")
# Install the fake module as the __main__ module. This allows
# the pickle module to work inside the user's code, since it now
# can know the module where the pickled objects stem from.
# IMPORTANT: This means we can't use "if __name__ == '__main__'" in
# our code, as it will point to the wrong module!!!
sys.modules["__main__"] = module
# Add special variables to the module's globals dict.
# Note: The following is a requirement for the CodeHasher to
# work correctly. The CodeHasher is scoped to
# files contained in the directory of __main__.__file__, which we
# assume is the main script directory.
module.__dict__["__file__"] = self._session_data.script_path
with modified_sys_path(
self._session_data), self._set_execing_flag():
# Run callbacks for widgets whose values have changed.
if rerun_data.widget_states is not None:
# Update the WidgetManager with the new widget_states.
# The old states, used to skip callbacks if values
# haven't changed, are also preserved in the
# WidgetManager.
self._session_state.compact_state()
self._session_state.set_widgets_from_proto(
rerun_data.widget_states)
self._session_state.call_callbacks()
ctx.on_script_start()
exec(code, module.__dict__)
self._session_state[SCRIPT_RUN_WITHOUT_ERRORS_KEY] = True
except RerunException as e:
rerun_with_data = e.rerun_data
except StopException:
pass
except BaseException as e:
self._session_state[SCRIPT_RUN_WITHOUT_ERRORS_KEY] = False
handle_uncaught_app_exception(e)
finally:
self._on_script_finished(ctx)
# Use _log_if_error() to make sure we never ever ever stop running the
# script without meaning to.
_log_if_error(_clean_problem_modules)
if rerun_with_data is not None:
self._run_script(rerun_with_data)
def _run_script(self, rerun_data):
"""Run our script.
Parameters
----------
rerun_data: RerunData
The RerunData to use.
"""
assert self._is_in_script_thread()
LOGGER.debug("Running script %s", rerun_data)
# Reset delta generator so it starts from index 0.
import streamlit as st
st._reset(self._main_dg, self._sidebar_dg)
self.on_event.send(ScriptRunnerEvent.SCRIPT_STARTED)
# Compile the script. Any errors thrown here will be surfaced
# to the user via a modal dialog in the frontend, and won't result
# in their previous report disappearing.
try:
# Python 3 got rid of the native execfile() command, so we read
# the file, compile it, and exec() it. This implementation is
# compatible with both 2 and 3.
with source_util.open_python_file(self._report.script_path) as f:
filebody = f.read()
if config.get_option("runner.magicEnabled"):
filebody = magic.add_magic(filebody, self._report.script_path)
code = compile(
filebody,
# Pass in the file path so it can show up in exceptions.
self._report.script_path,
# We're compiling entire blocks of Python, so we need "exec"
# mode (as opposed to "eval" or "single").
mode="exec",
# Don't inherit any flags or "future" statements.
flags=0,
dont_inherit=1,
# Parameter not supported in Python2:
# optimize=-1,
)
except BaseException as e:
# We got a compile error. Send an error event and bail immediately.
LOGGER.debug("Fatal script error: %s" % e)
self.on_event.send(
ScriptRunnerEvent.SCRIPT_STOPPED_WITH_COMPILE_ERROR,
exception=e)
return
# If we get here, we've successfully compiled our script. The next step
# is to run it. Errors thrown during execution will be shown to the
# user as ExceptionElements.
# Update the Widget singleton with the new widget_state
if rerun_data.widget_state is not None:
self._widgets.set_state(rerun_data.widget_state)
if config.get_option("runner.installTracer"):
self._install_tracer()
# This will be set to a RerunData instance if our execution
# is interrupted by a RerunException.
rerun_with_data = None
try:
# Create fake module. This gives us a name global namespace to
# execute the code in.
module = _new_module("__main__")
# Install the fake module as the __main__ module. This allows
# the pickle module to work inside the user's code, since it now
# can know the module where the pickled objects stem from.
# IMPORTANT: This means we can't use "if __name__ == '__main__'" in
# our code, as it will point to the wrong module!!!
sys.modules["__main__"] = module
# Add special variables to the module's globals dict.
# Note: The following is a requirement for the CodeHasher to
# work correctly. The CodeHasher is scoped to
# files contained in the directory of __main__.__file__, which we
# assume is the main script directory.
module.__dict__["__file__"] = self._report.script_path
with modified_sys_path(self._report), self._set_execing_flag():
exec(code, module.__dict__)
except RerunException as e:
rerun_with_data = e.rerun_data
except StopException:
pass
except BaseException as e:
# Show exceptions in the Streamlit report.
LOGGER.debug(e)
import streamlit as st
st.exception(e) # This is OK because we're in the script thread.
# TODO: Clean up the stack trace, so it doesn't include
# ScriptRunner.
finally:
self._widgets.reset_triggers()
self.on_event.send(ScriptRunnerEvent.SCRIPT_STOPPED_WITH_SUCCESS)
# Use _log_if_error() to make sure we never ever ever stop running the
# script without meaning to.
_log_if_error(_clean_problem_modules)
if rerun_with_data is not None:
self._run_script(rerun_with_data)
