LogStream

(class from pyomo.common.log)

class pyomo.common.log.LogStream(level, logger)

Bases: TextIOBase

This class logs whatever gets sent to the write method. This is useful for logging solver output (a LogStream instance can be handed to TeeStream from pyomo.common.tee).

__init__(level, logger)

Methods

__init__(level, logger)
close()	Flush and close the IO object.
detach()	Separate the underlying buffer from the TextIOBase and return it.
fileno()	Return underlying file descriptor if one exists.
flush()	Flush write buffers, if applicable.
isatty()	Return whether this is an 'interactive' stream.
read([size])	Read at most size characters from stream.
readable()	Return whether object was opened for reading.
readline([size])	Read until newline or EOF.
readlines([hint])	Return a list of lines from the stream.
redirect_streams(redirects)	Redirect StreamHandler objects to the original file descriptors
seek(offset[, whence])	Change the stream position to the given byte offset.
seekable()	Return whether object supports random access.
tell()	Return current stream position.
truncate([size])	Truncate file to size bytes.
writable()	Return whether object was opened for writing.
write(s)	Write string s to stream.
writelines(lines, /)	Write a list of lines to stream.

Attributes

closed
encoding	Encoding of the text stream.
errors	The error setting of the decoder or encoder.
newlines	Line endings translated so far.

Member Documentation

close()

Flush and close the IO object.

This method has no effect if the file is already closed.

detach()

Separate the underlying buffer from the TextIOBase and return it.

After the underlying buffer has been detached, the TextIO is in an unusable state.

fileno()

Return underlying file descriptor if one exists.

Raise OSError if the IO object does not use a file descriptor.

flush()

Flush write buffers, if applicable.

This is not implemented for read-only and non-blocking streams.

isatty()

Return whether this is an ‘interactive’ stream.

Return False if it can’t be determined.

read(size=-1, /)

Read at most size characters from stream.

Read from underlying buffer until we have size characters or we hit EOF. If size is negative or omitted, read until EOF.

readable()

Return whether object was opened for reading.

If False, read() will raise OSError.

readline(size=-1, /)

Read until newline or EOF.

Return an empty string if EOF is hit immediately. If size is specified, at most size characters will be read.

readlines(hint=-1, /)

Return a list of lines from the stream.

hint can be specified to control the number of lines read: no more lines will be read if the total size (in bytes/characters) of all lines so far exceeds hint.

redirect_streams(redirects)

Redirect StreamHandler objects to the original file descriptors

This utility method for py:class:~pyomo.common.tee.capture_output locates any StreamHandlers that would process messages from the logger assigned to this LogStream that would write to the file descriptors redirected by capture_output and yields context managers that will redirect those StreamHandlers back to duplicates of the original file descriptors.

seek(offset, whence=0, /)

Change the stream position to the given byte offset.

offset

The stream position, relative to ‘whence’.

whence

The relative position to seek from.

The offset is interpreted relative to the position indicated by whence. Values for whence are:

• os.SEEK_SET or 0 – start of stream (the default); offset should be zero or positive

• os.SEEK_CUR or 1 – current stream position; offset may be negative

• os.SEEK_END or 2 – end of stream; offset is usually negative

Return the new absolute position.

seekable()

Return whether object supports random access.

If False, seek(), tell() and truncate() will raise OSError. This method may need to do a test seek().

tell()

Return current stream position.

truncate(size=None, /)

Truncate file to size bytes.

File pointer is left unchanged. Size defaults to the current IO position as reported by tell(). Return the new size.

writable()

Return whether object was opened for writing.

If False, write() will raise OSError.

write(s: str) → int

Write string s to stream.

Return the number of characters written (which is always equal to the length of the string).

writelines(lines, /)

Write a list of lines to stream.

Line separators are not added, so it is usual for each of the lines provided to have a line separator at the end.

encoding

Encoding of the text stream.

Subclasses should override.

errors

The error setting of the decoder or encoder.

Subclasses should override.

newlines

Line endings translated so far.

Only line endings translated during reading are considered.

Subclasses should override.