Initial commit.

Author: jmcarp

.gitignore

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+*.py[cod]
+
+# C extensions
+*.so
+
+# Packages
+*.egg
+*.egg-info
+dist
+build
+eggs
+parts
+bin
+var
+sdist
+develop-eggs
+.installed.cfg
+lib
+lib64
+
+# Installer logs
+pip-log.txt
+
+# Unit test / coverage reports
+.coverage
+.tox
+nosetests.xml
+
+# Translations
+*.mo
+
+# Mr Developer
+.mr.developer.cfg
+.project
+.pydevproject
+
+# Complexity
+output/*.html
+output/*/index.html
+
+# Sphinx
+docs/_build
+README.html
+
+_sandbox

LICENSE

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+Copyright 2016 Joshua Carp
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

README.rst

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+=================
+sqlalchemy-export
+=================

setup.cfg

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+[wheel]
+# This flag says that the code is written to work on both Python 2 and Python
+# 3. If at all possible, it is good practice to do this. If you cannot, you
+# will need to generate wheels for each Python version that you support.
+universal=1
+
+# E127: continuation line over-indented for visual indent
+# E128: continuation line under-indented for visual indent
+# E265: block comment should start with #
+# E301: expected 1 blank line, found 1
+# E302: expected 2 blank lines, found 0
+[flake8]
+ignore = E127,E128,E265,E301,E302
+max-line-length = 90

setup.py

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+# -*- coding: utf-8 -*-
+
+import re
+from setuptools import setup
+from setuptools import find_packages
+
+REQUIRES = [
+    'six',
+    'sqlalchemy',
+]
+
+def find_version(fname):
+    """Attempts to find the version number in the file names fname.
+    Raises RuntimeError if not found.
+    """
+    version = ''
+    with open(fname, 'r') as fp:
+        reg = re.compile(r'__version__ = [\'"]([^\'"]*)[\'"]')
+        for line in fp:
+            m = reg.match(line)
+            if m:
+                version = m.group(1)
+                break
+    if not version:
+        raise RuntimeError('Cannot find version information')
+    return version
+
+def read(fname):
+    with open(fname) as fp:
+        content = fp.read()
+    return content
+
+setup(
+    name='sqlalchemy-export',
+    version=find_version('sqlalchemy_export/__init__.py'),
+    description='Bulk export utilities for SQLAlchemy',
+    long_description=read('README.rst'),
+    author='Joshua Carp',
+    author_email='[email protected]',
+    url='https://github.com/jmcarp/sqlalchemy-export',
+    packages=find_packages(exclude=('test*', )),
+    package_dir={'sqlalchemy_export': 'sqlalchemy_export'},
+    include_package_data=True,
+    install_requires=REQUIRES,
+    license=read('LICENSE'),
+    zip_safe=False,
+    keywords='sqlalchemy-export',
+    classifiers=[
+        'Development Status :: 2 - Pre-Alpha',
+        'Intended Audience :: Developers',
+        'License :: OSI Approved :: MIT License',
+        'Natural Language :: English',
+        'Programming Language :: Python :: 2',
+        'Programming Language :: Python :: 2.7',
+        'Programming Language :: Python :: 3',
+        'Programming Language :: Python :: 3.3',
+        'Programming Language :: Python :: 3.4',
+    ],
+    test_suite='tests',
+)

sqlalchemy_export/__init__.py

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+import six
+
+from sqlalchemy.sql import ColumnElement
+from sqlalchemy.orm import Mapper, class_mapper
+from sqlalchemy.orm.exc import UnmappedClassError
+from sqlalchemy.dialects import postgresql
+
+__version__ = '0.1.0'
+
+def export(select, engine, fp, **flags):
+    """Export a query or select to a file. For flags, see the PostgreSQL
+    documentation at http://www.postgresql.org/docs/9.5/static/sql-copy.html.
+
+    Examples: ::
+        select = MyTable.select()
+        with open('/path/to/file.tsv', 'w') as fp:
+            export(select, engine, fp)
+
+        query = session.query(MyModel)
+        with open('/path/to/file/csv', 'w') as fp:
+            export(query, engine, fp, format='csv', null='.')
+
+    :param select: SQLAlchemy query or select
+    :param engine: SQLAlchemy engine
+    :param fp: File pointer, using write mode
+    """
+    dialect = postgresql.dialect()
+    statement = getattr(select, 'statement', select)
+    compiled = statement.compile(dialect=dialect)
+    conn = engine.raw_connection()
+    cursor = conn.cursor()
+    query = cursor.mogrify(compiled.string, compiled.params).decode()
+    formatted_flags = '({})'.format(format_flags(flags)) if flags else ''
+    copy = 'COPY ({}) TO STDOUT {}'.format(query, formatted_flags)
+    cursor.copy_expert(copy, fp)
+    conn.close()
+
+def format_flags(flags):
+    return ', '.join(
+        '{} {}'.format(key.upper(), format_flag(value))
+        for key, value in flags.items()
+    )
+
+def format_flag(value):
+    return (
+        six.text_type(value).upper()
+        if isinstance(value, bool)
+        else repr(value)
+    )
+
+def label_entities(query):
+    entities = sum(
+        [extract_entities(defn) for defn in query.column_definitions],
+        []
+    )
+    return query.with_entities(*entities)
+
+def extract_entities(defn):
+    expr = defn['expr']
+    if isinstance(expr, Mapper):
+        return extract_mapper_entities(expr)
+    elif is_model(expr):
+        return extract_mapper_entities(expr.__mapper__)
+    elif isinstance(expr, ColumnElement):
+        return expr
+    else:
+        raise ValueError()
+
+def extract_mapper_entities(mapper):
+    model = mapper.class_
+    return [
+        getattr(model, prop.key).label(prop.key)
+        for prop in mapper.column_attrs
+    ]
+
+def is_model(class_):
+    try:
+        class_mapper(class_)
+        return True
+    except UnmappedClassError:
+        return False