def update_check(settings):

    # Get Web2py environment into our globals.
    #globals().update(**environment)
    request = current.request

    # Fatal errors
    errors = []
    # Non-fatal warnings
    warnings = []

    # -------------------------------------------------------------------------
    # Check Python libraries

    # Get mandatory global dependencies
    app_path = request.folder

    gr_path = os.path.join(app_path, "requirements.txt")
    or_path = os.path.join(app_path, "optional_requirements.txt")

    global_dep = parse_requirements({}, gr_path)
    optional_dep = parse_requirements({}, or_path)

    templates = settings.get_template()
    location = settings.get_template_location()
    if not isinstance(templates, (tuple, list)):
        templates = (templates,)
    template_dep = {}
    template_optional_dep = {}
    for template in templates:
        tr_path = os.path.join(app_path, location, "templates", template, "requirements.txt")
        tor_path = os.path.join(app_path, location, "templates", template, "optional_requirements.txt")
        parse_requirements(template_dep, tr_path)
        parse_requirements(template_optional_dep, tor_path)

    # Remove optional dependencies which are already accounted for in template dependencies
    unique = set(optional_dep.keys()).difference(set(template_dep.keys()))
    for dependency in optional_dep.keys():
        if dependency not in unique:
            del optional_dep[dependency]

    # Override optional dependency messages from template
    unique = set(optional_dep.keys()).difference(set(template_optional_dep.keys()))
    for dependency in optional_dep.keys():
        if dependency not in unique:
            del optional_dep[dependency]

    errors, warnings = s3_check_python_lib(global_dep, template_dep, template_optional_dep, optional_dep)
    # @ToDo: Move these to Template
    # for now this is done in s3db.climate_first_run()
    if settings.has_module("climate"):
        if settings.get_database_type() != "postgres":
            errors.append("Climate unresolved dependency: PostgreSQL required")
        try:
           import rpy2
        except ImportError:
           errors.append("Climate unresolved dependency: RPy2 required")
        try:
           from Scientific.IO import NetCDF
        except ImportError:
           warnings.append("Climate unresolved dependency: NetCDF required if you want to import readings")
        try:
           from scipy import stats
        except ImportError:
           warnings.append("Climate unresolved dependency: SciPy required if you want to generate graphs on the map")

    # -------------------------------------------------------------------------
    # Check Web2Py version
    #
    # Currently, the minimum usable Web2py is determined by whether the
    # Scheduler is available
    web2py_minimum_version = "Version 2.4.7-stable+timestamp.2013.05.27.11.49.44"
    # Offset of datetime in return value of parse_version.
    datetime_index = 4
    web2py_version_ok = True
    try:
        from gluon.fileutils import parse_version
    except ImportError:
        web2py_version_ok = False
    if web2py_version_ok:
        try:
            web2py_minimum_parsed = parse_version(web2py_minimum_version)
            web2py_minimum_datetime = web2py_minimum_parsed[datetime_index]
            version_info = open("VERSION", "r")
            web2py_installed_version = version_info.read().split()[-1].strip()
            version_info.close()
            if isinstance(web2py_installed_version, str):
                # Post 2.4.2, global_settings.web2py_version is unparsed
                web2py_installed_parsed = parse_version(web2py_installed_version)
                web2py_installed_datetime = web2py_installed_parsed[datetime_index]
            else:
                # 2.4.2 & earlier style
                web2py_installed_datetime = web2py_installed_version[datetime_index]
            web2py_version_ok = web2py_installed_datetime >= web2py_minimum_datetime
        except:
            # Will get AttributeError if Web2py's parse_version is too old for
            # its current version format, which changed in 2.3.2.
            web2py_version_ok = False
    if not web2py_version_ok:
        warnings.append(
            "The installed version of Web2py is too old to support the current version of Sahana Eden."
            "\nPlease upgrade Web2py to at least version: %s" % \
            web2py_minimum_version)

    # -------------------------------------------------------------------------
    # Create required directories if needed
    databases_dir = os.path.join(app_path, "databases")
    try:
        os.stat(databases_dir)
    except OSError:
        # not found, create it
        os.mkdir(databases_dir)

    # -------------------------------------------------------------------------
    # Copy in Templates
    # - 000_config.py (machine-specific settings)
    # - rest are run in-place
    #
    template_folder = os.path.join(app_path, "modules", "templates")

    template_files = {
        # source : destination
        "000_config.py" : os.path.join("models", "000_config.py"),
    }

    copied_from_template = []

    for t in template_files:
        src_path = os.path.join(template_folder, t)
        dst_path = os.path.join(app_path, template_files[t])
        try:
            os.stat(dst_path)
        except OSError:
            # Not found, copy from template
            if t == "000_config.py":
                input = open(src_path)
                output = open(dst_path, "w")
                for line in input:
                    if "akeytochange" in line:
                        # Generate a random hmac_key to secure the passwords in case
                        # the database is compromised
                        import uuid
                        hmac_key = uuid.uuid4()
                        line = 'settings.auth.hmac_key = "%s"' % hmac_key
                    output.write(line)
                output.close()
                input.close()
            else:
                import shutil
                shutil.copy(src_path, dst_path)
            copied_from_template.append(template_files[t])

            # @ToDo: WebSetup
            #  http://eden.sahanafoundation.org/wiki/DeveloperGuidelines/WebSetup
            #if not os.path.exists("%s/applications/websetup" % os.getcwd()):
            #    # @ToDo: Check Permissions
            #    # Copy files into this folder (@ToDo: Pythonise)
            #    cp -r private/websetup "%s/applications" % os.getcwd()
            # Launch WebSetup
            #redirect(URL(a="websetup", c="default", f="index",
            #             vars=dict(appname=request.application,
            #                       firstTime="True")))
        else:
            # Found the file in the destination
            # Check if it has been edited
            import re
            edited_pattern = r"FINISHED_EDITING_\w*\s*=\s*(True|False)"
            edited_matcher = re.compile(edited_pattern).match
            has_edited = False
            with open(dst_path) as f:
                for line in f:
                    edited_result = edited_matcher(line)
                    if edited_result:
                        has_edited = True
                        edited = edited_result.group(1)
                        break
            if has_edited and (edited != "True"):
                errors.append("Please edit %s before starting the system." % t)
            # Check if it's up to date (i.e. a critical update requirement)
            version_pattern = r"VERSION =\s*([0-9]+)"
            version_matcher = re.compile(version_pattern).match
            has_version = False
            with open(dst_path) as f:
                for line in f:
                    version_result = version_matcher(line)
                    if version_result:
                        has_version = True
                        version = version_result.group(1)
                        break
            if not has_version:
                error = "Your %s is using settings from the old templates system. Please switch to the new templates system: http://eden.sahanafoundation.org/wiki/DeveloperGuidelines/Templates" % t
                errors.append(error)
            elif int(version) != VERSION:
                error = "Your %s is using settings from template version %s. Please update with new settings from template version %s before starting the system." % \
                                (t, version, VERSION)
                errors.append(error)

    if copied_from_template:
        errors.append(
            "The following files were copied from templates and should be edited: %s" %
            ", ".join(copied_from_template))

    return {"error_messages": errors, "warning_messages": warnings}

# -------------------------------------------------------------------------
Gets a list of subjects from the DRCOG data catalog
dataset/ETHPy150Open sahana/eden/modules/s3_update_check.py/update_check--crossover with--dataset/ETHPy150Open opencolorado/OpenColorado-Tools-and-Utilities/Scripts/Harvest/Drcog/DrcogSync.py/get_subjects