[github/fretlink/tap-google-sheets.git] / tap_google_sheets / schema.py

import os
import json
import re
import urllib.parse
from collections import OrderedDict
import singer
from singer import metadata
from tap_google_sheets.streams import STREAMS

LOGGER = singer.get_logger()

# Reference:
# https://github.com/singer-io/getting-started/blob/master/docs/DISCOVERY_MODE.md#Metadata

# Convert column index to column letter
def colnum_string(num):
    string = ""
    while num > 0:
        num, remainder = divmod(num - 1, 26)
        string = chr(65 + remainder) + string
    return string


# Create sheet_metadata_json with columns from sheet
def get_sheet_schema_columns(sheet):
    sheet_title = sheet.get('properties', {}).get('title')
    sheet_json_schema = OrderedDict()
    data = next(iter(sheet.get('data', [])), {})
    row_data = data.get('rowData', [])
    if row_data == []:
        # Empty sheet, SKIP
        LOGGER.info('SKIPPING Empty Sheet: {}'.format(sheet_title))
        return None, None
    # spreadsheet is an OrderedDict, with orderd sheets and rows in the repsonse
    headers = row_data[0].get('values', [])
    first_values = row_data[1].get('values', [])
    # LOGGER.info('first_values = {}'.format(json.dumps(first_values, indent=2, sort_keys=True)))

    sheet_json_schema = {
        'type': 'object',
        'additionalProperties': False,
        'properties': {
            '__sdc_spreadsheet_id': {
                'type': ['null', 'string']
            },
            '__sdc_sheet_id': {
                'type': ['null', 'integer']
            },
            '__sdc_row': {
                'type': ['null', 'integer']
            }
        }
    }

    header_list = [] # used for checking uniqueness
    columns = []
    prior_header = None
    i = 0
    skipped = 0
    # Read column headers until end or 2 consecutive skipped headers
    for header in headers:
        # LOGGER.info('header = {}'.format(json.dumps(header, indent=2, sort_keys=True)))
        column_index = i + 1
        column_letter = colnum_string(column_index)
        header_value = header.get('formattedValue')
        if header_value: # NOT skipped
            column_is_skipped = False
            skipped = 0
            column_name = '{}'.format(header_value)
            if column_name in header_list:
                raise Exception('DUPLICATE HEADER ERROR: SHEET: {}, COL: {}, CELL: {}1'.format(
                    sheet_title, column_name, column_letter))
            header_list.append(column_name)

            first_value = None
            try:
                first_value = first_values[i]
            except IndexError as err:
                LOGGER.info('NO VALUE IN 2ND ROW FOR HEADER. SHEET: {}, COL: {}, CELL: {}2. {}'.format(
                    sheet_title, column_name, column_letter, err))
                first_value = {}
                first_values.append(first_value)
                pass

            column_effective_value = first_value.get('effectiveValue', {})

            col_val = None
            if column_effective_value == {}:
                column_effective_value_type = 'stringValue'
                LOGGER.info('WARNING: NO VALUE IN 2ND ROW FOR HEADER. SHEET: {}, COL: {}, CELL: {}2.'.format(
                    sheet_title, column_name, column_letter))
                LOGGER.info('   Setting column datatype to STRING')
            else:
                for key, val in column_effective_value.items():
                    if key in ('numberValue', 'stringValue', 'boolValue'):
                        column_effective_value_type = key
                        col_val = str(val)
                    elif key in ('errorType', 'formulaType'):
                        col_val = str(val)
                        raise Exception('DATA TYPE ERROR 2ND ROW VALUE: SHEET: {}, COL: {}, CELL: {}2, TYPE: {}, VALUE: {}'.format(
                            sheet_title, column_name, column_letter, key, col_val))

            column_number_format = first_values[i].get('effectiveFormat', {}).get(
                'numberFormat', {})
            column_number_format_type = column_number_format.get('type')

            # Determine datatype for sheet_json_schema
            #
            # column_effective_value_type = numberValue, stringValue, boolValue;
            #  INVALID: errorType, formulaType
            #  https://developers.google.com/sheets/api/reference/rest/v4/spreadsheets/other#ExtendedValue
            #
            # column_number_format_type = UNEPECIFIED, TEXT, NUMBER, PERCENT, CURRENCY, DATE,
            #   TIME, DATE_TIME, SCIENTIFIC
            #  https://developers.google.com/sheets/api/reference/rest/v4/spreadsheets/cells#NumberFormatType
            #
            column_format = None # Default
            if column_effective_value == {}:
                col_properties = {'type': ['null', 'string']}
                column_gs_type = 'stringValue'
                LOGGER.info('WARNING: 2ND ROW VALUE IS BLANK: SHEET: {}, COL: {}, CELL: {}2'.format(
                        sheet_title, column_name, column_letter))
                LOGGER.info('   Setting column datatype to STRING')
            elif column_effective_value_type == 'stringValue':
                col_properties = {'type': ['null', 'string']}
                column_gs_type = 'stringValue'
            elif column_effective_value_type == 'boolValue':
                col_properties = {'type': ['null', 'boolean', 'string']}
                column_gs_type = 'boolValue'
            elif column_effective_value_type == 'numberValue':
                if column_number_format_type == 'DATE_TIME':
                    col_properties = {
                        'type': ['null', 'string'],
                        'format': 'date-time'
                    }
                    column_gs_type = 'numberType.DATE_TIME'
                elif column_number_format_type == 'DATE':
                    col_properties = {
                        'type': ['null', 'string'],
                        'format': 'date'
                    }
                    column_gs_type = 'numberType.DATE'
                elif column_number_format_type == 'TIME':
                    col_properties = {
                        'type': ['null', 'string'],
                        'format': 'time'
                    }
                    column_gs_type = 'numberType.TIME'
                elif column_number_format_type == 'TEXT':
                    col_properties = {'type': ['null', 'string']}
                    column_gs_type = 'stringValue'
                else:
                    # Interesting - order in the anyOf makes a difference.
                    # Number w/ multipleOf must be listed last, otherwise errors occur.
                    col_properties =  {
                        'anyOf': [
                            {
                                'type': 'null'
                            },
                            {
                                'type': 'number',
                                'multipleOf': 1e-15
                            },
                            {
                                'type': 'string'
                            }
                        ]
                    }
                    column_gs_type = 'numberType'
            # Catch-all to deal with other types and set to string
            # column_effective_value_type: formulaValue, errorValue, or other
            else:
                col_properties = {'type': ['null', 'string']}
                column_gs_type = 'unsupportedValue'
                LOGGER.info('WARNING: UNSUPPORTED 2ND ROW VALUE: SHEET: {}, COL: {}, CELL: {}2, TYPE: {}, VALUE: {}'.format(
                        sheet_title, column_name, column_letter, column_effective_value_type, col_val))
                LOGGER.info('Converting to string.')
        else: # skipped
            column_is_skipped = True
            skipped = skipped + 1
            column_index_str = str(column_index).zfill(2)
            column_name = '__sdc_skip_col_{}'.format(column_index_str)
            col_properties = {'type': ['null', 'string']}
            column_gs_type = 'stringValue'
            LOGGER.info('WARNING: SKIPPED COLUMN; NO COLUMN HEADER. SHEET: {}, COL: {}, CELL: {}1'.format(
                sheet_title, column_name, column_letter))
            LOGGER.info('  This column will be skipped during data loading.')

        if skipped >= 2:
            # skipped = 2 consecutive skipped headers
            # Remove prior_header column_name
            sheet_json_schema['properties'].pop(prior_header, None)
            LOGGER.info('TWO CONSECUTIVE SKIPPED COLUMNS. STOPPING SCAN AT: SHEET: {}, COL: {}, CELL {}1'.format(
                sheet_title, column_name, column_letter))
            break

        else:
            column = {}
            column = {
                'columnIndex': column_index,
                'columnLetter': column_letter,
                'columnName': column_name,
                'columnType': column_gs_type,
                'columnSkipped': column_is_skipped
            }
            columns.append(column)

            sheet_json_schema['properties'][column_name] = col_properties

        prior_header = column_name
        i = i + 1

    return sheet_json_schema, columns


# Get Header Row and 1st data row (Rows 1 & 2) from a Sheet on Spreadsheet w/ sheet_metadata query
#   endpoint: spreadsheets/{spreadsheet_id}
#   params: includeGridData = true, ranges = '{sheet_title}'!1:2
# This endpoint includes detailed metadata about each cell - incl. data type, formatting, etc.
def get_sheet_metadata(sheet, spreadsheet_id, client):
    sheet_id = sheet.get('properties', {}).get('sheetId')
    sheet_title = sheet.get('properties', {}).get('title')
    LOGGER.info('sheet_id = {}, sheet_title = {}'.format(sheet_id, sheet_title))

    stream_name = 'sheet_metadata'
    stream_metadata = STREAMS.get(stream_name)
    api = stream_metadata.get('api', 'sheets')
    params = stream_metadata.get('params', {})
    sheet_title_encoded = urllib.parse.quote_plus(sheet_title)
    sheet_title_escaped = re.escape(sheet_title)
    querystring = '&'.join(['%s=%s' % (key, value) for (key, value) in \
        params.items()]).replace('{sheet_title}', sheet_title_encoded)
    path = '{}?{}'.format(stream_metadata.get('path').replace('{spreadsheet_id}', \
        spreadsheet_id), querystring)

    sheet_md_results = client.get(path=path, api=api, endpoint=sheet_title_escaped)
    # sheet_metadata: 1st `sheets` node in results
    sheet_metadata = sheet_md_results.get('sheets')[0]

    # Create sheet_json_schema (for discovery/catalog) and columns (for sheet_metadata results)
    try:
        sheet_json_schema, columns = get_sheet_schema_columns(sheet_metadata)
    except Exception as err:
        LOGGER.warning('{}'.format(err))
        LOGGER.warning('SKIPPING Malformed sheet: {}'.format(sheet_title))
        sheet_json_schema, columns = None, None

    return sheet_json_schema, columns


def get_abs_path(path):
    return os.path.join(os.path.dirname(os.path.realpath(__file__)), path)

def get_schemas(client, spreadsheet_id):
    schemas = {}
    field_metadata = {}

    for stream_name, stream_metadata in STREAMS.items():
        schema_path = get_abs_path('schemas/{}.json'.format(stream_name))
        with open(schema_path) as file:
            schema = json.load(file)
        schemas[stream_name] = schema
        mdata = metadata.new()

        # Documentation:
        # https://github.com/singer-io/getting-started/blob/master/docs/DISCOVERY_MODE.md#singer-python-helper-functions
        # Reference:
        # https://github.com/singer-io/singer-python/blob/master/singer/metadata.py#L25-L44
        mdata = metadata.get_standard_metadata(
            schema=schema,
            key_properties=stream_metadata.get('key_properties', None),
            valid_replication_keys=stream_metadata.get('replication_keys', None),
            replication_method=stream_metadata.get('replication_method', None)
        )
        field_metadata[stream_name] = mdata

        if stream_name == 'spreadsheet_metadata':
            api = stream_metadata.get('api', 'sheets')
            params = stream_metadata.get('params', {})
            querystring = '&'.join(['%s=%s' % (key, value) for (key, value) in params.items()])
            path = '{}?{}'.format(stream_metadata.get('path').replace('{spreadsheet_id}', \
                spreadsheet_id), querystring)

            # GET spreadsheet_metadata, which incl. sheets (basic metadata for each worksheet)
            spreadsheet_md_results = client.get(path=path, params=querystring, api=api, \
                endpoint=stream_name)

            sheets = spreadsheet_md_results.get('sheets')
            if sheets:
                # Loop thru each worksheet in spreadsheet
                for sheet in sheets:
                    # GET sheet_json_schema for each worksheet (from function above)
                    sheet_json_schema, columns = get_sheet_metadata(sheet, spreadsheet_id, client)

                    # SKIP empty sheets (where sheet_json_schema and columns are None)
                    if sheet_json_schema and columns:
                        sheet_title = sheet.get('properties', {}).get('title')
                        schemas[sheet_title] = sheet_json_schema
                        sheet_mdata = metadata.new()
                        sheet_mdata = metadata.get_standard_metadata(
                            schema=sheet_json_schema,
                            key_properties=['__sdc_row'],
                            valid_replication_keys=None,
                            replication_method='FULL_TABLE'
                        )
                        field_metadata[sheet_title] = sheet_mdata

    return schemas, field_metadata
Commit	Line	Data
89643ba6 JH	1	import os
89643ba6 JH	2	import json
5fc2ead5 JH	3	import re
5fc2ead5 JH	4	import urllib.parse
89643ba6 JH	5	from collections import OrderedDict
	6	import singer
	7	from singer import metadata
	8	from tap_google_sheets.streams import STREAMS
	9
	10	LOGGER = singer.get_logger()
	11
	12	# Reference:
	13	# https://github.com/singer-io/getting-started/blob/master/docs/DISCOVERY_MODE.md#Metadata
	14
	15	# Convert column index to column letter
99424fee	16	def colnum_string(num):
89643ba6	17	string = ""
99424fee JH	18	while num > 0:
99424fee JH	19	num, remainder = divmod(num - 1, 26)
89643ba6 JH	20	string = chr(65 + remainder) + string
	21	return string
	22
	23
	24	# Create sheet_metadata_json with columns from sheet
99424fee	25	def get_sheet_schema_columns(sheet):
43a24cba	26	sheet_title = sheet.get('properties', {}).get('title')
89643ba6 JH	27	sheet_json_schema = OrderedDict()
89643ba6 JH	28	data = next(iter(sheet.get('data', [])), {})
99424fee	29	row_data = data.get('rowData', [])
376f1145 JH	30	if row_data == []:
	31	# Empty sheet, SKIP
	32	LOGGER.info('SKIPPING Empty Sheet: {}'.format(sheet_title))
	33	return None, None
f6d7c509	34	# spreadsheet is an OrderedDict, with orderd sheets and rows in the repsonse
	35	headers = row_data[0].get('values', [])
	36	first_values = row_data[1].get('values', [])
	37	# LOGGER.info('first_values = {}'.format(json.dumps(first_values, indent=2, sort_keys=True)))
376f1145	38
f6d7c509	39	sheet_json_schema = {
	40	'type': 'object',
	41	'additionalProperties': False,
	42	'properties': {
	43	'__sdc_spreadsheet_id': {
	44	'type': ['null', 'string']
	45	},
	46	'__sdc_sheet_id': {
	47	'type': ['null', 'integer']
	48	},
	49	'__sdc_row': {
	50	'type': ['null', 'integer']
89643ba6 JH	51	}
89643ba6 JH	52	}
f6d7c509	53	}
376f1145	54
f6d7c509	55	header_list = [] # used for checking uniqueness
	56	columns = []
	57	prior_header = None
	58	i = 0
	59	skipped = 0
	60	# Read column headers until end or 2 consecutive skipped headers
	61	for header in headers:
	62	# LOGGER.info('header = {}'.format(json.dumps(header, indent=2, sort_keys=True)))
	63	column_index = i + 1
	64	column_letter = colnum_string(column_index)
	65	header_value = header.get('formattedValue')
	66	if header_value: # NOT skipped
	67	column_is_skipped = False
	68	skipped = 0
	69	column_name = '{}'.format(header_value)
	70	if column_name in header_list:
	71	raise Exception('DUPLICATE HEADER ERROR: SHEET: {}, COL: {}, CELL: {}1'.format(
	72	sheet_title, column_name, column_letter))
	73	header_list.append(column_name)
376f1145	74
f6d7c509	75	first_value = None
	76	try:
	77	first_value = first_values[i]
	78	except IndexError as err:
5fc2ead5	79	LOGGER.info('NO VALUE IN 2ND ROW FOR HEADER. SHEET: {}, COL: {}, CELL: {}2. {}'.format(
f6d7c509	80	sheet_title, column_name, column_letter, err))
5fc2ead5 JH	81	first_value = {}
	82	first_values.append(first_value)
	83	pass
376f1145	84
f6d7c509	85	column_effective_value = first_value.get('effectiveValue', {})
376f1145	86
f6d7c509	87	col_val = None
	88	if column_effective_value == {}:
	89	column_effective_value_type = 'stringValue'
	90	LOGGER.info('WARNING: NO VALUE IN 2ND ROW FOR HEADER. SHEET: {}, COL: {}, CELL: {}2.'.format(
	91	sheet_title, column_name, column_letter))
	92	LOGGER.info(' Setting column datatype to STRING')
	93	else:
	94	for key, val in column_effective_value.items():
	95	if key in ('numberValue', 'stringValue', 'boolValue'):
	96	column_effective_value_type = key
	97	col_val = str(val)
	98	elif key in ('errorType', 'formulaType'):
	99	col_val = str(val)
	100	raise Exception('DATA TYPE ERROR 2ND ROW VALUE: SHEET: {}, COL: {}, CELL: {}2, TYPE: {}, VALUE: {}'.format(
	101	sheet_title, column_name, column_letter, key, col_val))
376f1145	102
f6d7c509	103	column_number_format = first_values[i].get('effectiveFormat', {}).get(
	104	'numberFormat', {})
	105	column_number_format_type = column_number_format.get('type')
	106
	107	# Determine datatype for sheet_json_schema
	108	#
	109	# column_effective_value_type = numberValue, stringValue, boolValue;
	110	# INVALID: errorType, formulaType
	111	# https://developers.google.com/sheets/api/reference/rest/v4/spreadsheets/other#ExtendedValue
	112	#
	113	# column_number_format_type = UNEPECIFIED, TEXT, NUMBER, PERCENT, CURRENCY, DATE,
	114	# TIME, DATE_TIME, SCIENTIFIC
	115	# https://developers.google.com/sheets/api/reference/rest/v4/spreadsheets/cells#NumberFormatType
	116	#
	117	column_format = None # Default
	118	if column_effective_value == {}:
	119	col_properties = {'type': ['null', 'string']}
	120	column_gs_type = 'stringValue'
	121	LOGGER.info('WARNING: 2ND ROW VALUE IS BLANK: SHEET: {}, COL: {}, CELL: {}2'.format(
	122	sheet_title, column_name, column_letter))
	123	LOGGER.info(' Setting column datatype to STRING')
	124	elif column_effective_value_type == 'stringValue':
	125	col_properties = {'type': ['null', 'string']}
	126	column_gs_type = 'stringValue'
	127	elif column_effective_value_type == 'boolValue':
	128	col_properties = {'type': ['null', 'boolean', 'string']}
	129	column_gs_type = 'boolValue'
	130	elif column_effective_value_type == 'numberValue':
	131	if column_number_format_type == 'DATE_TIME':
	132	col_properties = {
	133	'type': ['null', 'string'],
	134	'format': 'date-time'
	135	}
	136	column_gs_type = 'numberType.DATE_TIME'
	137	elif column_number_format_type == 'DATE':
	138	col_properties = {
	139	'type': ['null', 'string'],
	140	'format': 'date'
	141	}
	142	column_gs_type = 'numberType.DATE'
	143	elif column_number_format_type == 'TIME':
	144	col_properties = {
	145	'type': ['null', 'string'],
	146	'format': 'time'
	147	}
	148	column_gs_type = 'numberType.TIME'
	149	elif column_number_format_type == 'TEXT':
5890b89c	150	col_properties = {'type': ['null', 'string']}
89643ba6 JH	151	column_gs_type = 'stringValue'
89643ba6 JH	152	else:
f6d7c509	153	# Interesting - order in the anyOf makes a difference.
	154	# Number w/ multipleOf must be listed last, otherwise errors occur.
	155	col_properties = {
	156	'anyOf': [
	157	{
	158	'type': 'null'
	159	},
	160	{
	161	'type': 'number',
	162	'multipleOf': 1e-15
	163	},
	164	{
	165	'type': 'string'
	166	}
	167	]
	168	}
	169	column_gs_type = 'numberType'
	170	# Catch-all to deal with other types and set to string
	171	# column_effective_value_type: formulaValue, errorValue, or other
	172	else:
5890b89c	173	col_properties = {'type': ['null', 'string']}
f6d7c509	174	column_gs_type = 'unsupportedValue'
	175	LOGGER.info('WARNING: UNSUPPORTED 2ND ROW VALUE: SHEET: {}, COL: {}, CELL: {}2, TYPE: {}, VALUE: {}'.format(
	176	sheet_title, column_name, column_letter, column_effective_value_type, col_val))
	177	LOGGER.info('Converting to string.')
	178	else: # skipped
	179	column_is_skipped = True
	180	skipped = skipped + 1
	181	column_index_str = str(column_index).zfill(2)
	182	column_name = '__sdc_skip_col_{}'.format(column_index_str)
	183	col_properties = {'type': ['null', 'string']}
	184	column_gs_type = 'stringValue'
	185	LOGGER.info('WARNING: SKIPPED COLUMN; NO COLUMN HEADER. SHEET: {}, COL: {}, CELL: {}1'.format(
	186	sheet_title, column_name, column_letter))
	187	LOGGER.info(' This column will be skipped during data loading.')
89643ba6	188
f6d7c509	189	if skipped >= 2:
	190	# skipped = 2 consecutive skipped headers
	191	# Remove prior_header column_name
	192	sheet_json_schema['properties'].pop(prior_header, None)
	193	LOGGER.info('TWO CONSECUTIVE SKIPPED COLUMNS. STOPPING SCAN AT: SHEET: {}, COL: {}, CELL {}1'.format(
	194	sheet_title, column_name, column_letter))
	195	break
89643ba6	196
f6d7c509	197	else:
	198	column = {}
	199	column = {
	200	'columnIndex': column_index,
	201	'columnLetter': column_letter,
	202	'columnName': column_name,
	203	'columnType': column_gs_type,
	204	'columnSkipped': column_is_skipped
	205	}
	206	columns.append(column)
89643ba6	207
f6d7c509	208	sheet_json_schema['properties'][column_name] = col_properties
376f1145	209
f6d7c509	210	prior_header = column_name
f6d7c509	211	i = i + 1
376f1145	212
f6d7c509	213	return sheet_json_schema, columns
89643ba6 JH	214
89643ba6 JH	215
5890b89c JH	216	# Get Header Row and 1st data row (Rows 1 & 2) from a Sheet on Spreadsheet w/ sheet_metadata query
	217	# endpoint: spreadsheets/{spreadsheet_id}
	218	# params: includeGridData = true, ranges = '{sheet_title}'!1:2
	219	# This endpoint includes detailed metadata about each cell - incl. data type, formatting, etc.
89643ba6 JH	220	def get_sheet_metadata(sheet, spreadsheet_id, client):
	221	sheet_id = sheet.get('properties', {}).get('sheetId')
	222	sheet_title = sheet.get('properties', {}).get('title')
	223	LOGGER.info('sheet_id = {}, sheet_title = {}'.format(sheet_id, sheet_title))
	224
	225	stream_name = 'sheet_metadata'
	226	stream_metadata = STREAMS.get(stream_name)
	227	api = stream_metadata.get('api', 'sheets')
	228	params = stream_metadata.get('params', {})
5fc2ead5 JH	229	sheet_title_encoded = urllib.parse.quote_plus(sheet_title)
5fc2ead5 JH	230	sheet_title_escaped = re.escape(sheet_title)
99424fee	231	querystring = '&'.join(['%s=%s' % (key, value) for (key, value) in \
5fc2ead5	232	params.items()]).replace('{sheet_title}', sheet_title_encoded)
99424fee JH	233	path = '{}?{}'.format(stream_metadata.get('path').replace('{spreadsheet_id}', \
99424fee JH	234	spreadsheet_id), querystring)
89643ba6	235
5fc2ead5	236	sheet_md_results = client.get(path=path, api=api, endpoint=sheet_title_escaped)
5890b89c JH	237	# sheet_metadata: 1st `sheets` node in results
5890b89c JH	238	sheet_metadata = sheet_md_results.get('sheets')[0]
89643ba6	239
5890b89c	240	# Create sheet_json_schema (for discovery/catalog) and columns (for sheet_metadata results)
f6d7c509	241	try:
f6d7c509	242	sheet_json_schema, columns = get_sheet_schema_columns(sheet_metadata)
5fc2ead5 JH	243	except Exception as err:
	244	LOGGER.warning('{}'.format(err))
	245	LOGGER.warning('SKIPPING Malformed sheet: {}'.format(sheet_title))
f6d7c509	246	sheet_json_schema, columns = None, None
5890b89c JH	247
5890b89c JH	248	return sheet_json_schema, columns
89643ba6 JH	249
	250
	251	def get_abs_path(path):
	252	return os.path.join(os.path.dirname(os.path.realpath(__file__)), path)
	253
	254	def get_schemas(client, spreadsheet_id):
	255	schemas = {}
	256	field_metadata = {}
	257
	258	for stream_name, stream_metadata in STREAMS.items():
	259	schema_path = get_abs_path('schemas/{}.json'.format(stream_name))
	260	with open(schema_path) as file:
	261	schema = json.load(file)
	262	schemas[stream_name] = schema
	263	mdata = metadata.new()
	264
	265	# Documentation:
	266	# https://github.com/singer-io/getting-started/blob/master/docs/DISCOVERY_MODE.md#singer-python-helper-functions
	267	# Reference:
	268	# https://github.com/singer-io/singer-python/blob/master/singer/metadata.py#L25-L44
	269	mdata = metadata.get_standard_metadata(
	270	schema=schema,
	271	key_properties=stream_metadata.get('key_properties', None),
	272	valid_replication_keys=stream_metadata.get('replication_keys', None),
	273	replication_method=stream_metadata.get('replication_method', None)
	274	)
	275	field_metadata[stream_name] = mdata
99424fee	276
89643ba6 JH	277	if stream_name == 'spreadsheet_metadata':
	278	api = stream_metadata.get('api', 'sheets')
	279	params = stream_metadata.get('params', {})
	280	querystring = '&'.join(['%s=%s' % (key, value) for (key, value) in params.items()])
99424fee JH	281	path = '{}?{}'.format(stream_metadata.get('path').replace('{spreadsheet_id}', \
99424fee JH	282	spreadsheet_id), querystring)
89643ba6	283
5890b89c	284	# GET spreadsheet_metadata, which incl. sheets (basic metadata for each worksheet)
99424fee JH	285	spreadsheet_md_results = client.get(path=path, params=querystring, api=api, \
99424fee JH	286	endpoint=stream_name)
89643ba6 JH	287
	288	sheets = spreadsheet_md_results.get('sheets')
	289	if sheets:
5890b89c	290	# Loop thru each worksheet in spreadsheet
89643ba6	291	for sheet in sheets:
5890b89c JH	292	# GET sheet_json_schema for each worksheet (from function above)
5890b89c JH	293	sheet_json_schema, columns = get_sheet_metadata(sheet, spreadsheet_id, client)
376f1145 JH	294
	295	# SKIP empty sheets (where sheet_json_schema and columns are None)
	296	if sheet_json_schema and columns:
	297	sheet_title = sheet.get('properties', {}).get('title')
	298	schemas[sheet_title] = sheet_json_schema
	299	sheet_mdata = metadata.new()
	300	sheet_mdata = metadata.get_standard_metadata(
	301	schema=sheet_json_schema,
	302	key_properties=['__sdc_row'],
	303	valid_replication_keys=None,
	304	replication_method='FULL_TABLE'
	305	)
	306	field_metadata[sheet_title] = sheet_mdata
99424fee	307
89643ba6	308	return schemas, field_metadata