diff query_mass_repos.py @ 23:85fd05d0d16c

New tool to Query multiple public repositories for elemental compositions from accurate mass values detected by high-resolution mass spectrometers
author pieter.lukasse@wur.nl
date Thu, 03 Apr 2014 16:44:11 +0200
parents
children 60b53f2aa48a
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/query_mass_repos.py	Thu Apr 03 16:44:11 2014 +0200
@@ -0,0 +1,289 @@
+#!/usr/bin/env python
+# encoding: utf-8
+'''
+Module to query a set of accurate mass values detected by high-resolution mass spectrometers
+against various repositories/services such as METabolomics EXPlorer database or the 
+MFSearcher service (http://webs2.kazusa.or.jp/mfsearcher/).
+
+It will take the input file and for each record it will query the 
+molecular mass in the selected repository/service. If one or more compounds are found 
+then extra information regarding these compounds is added to the output file.
+
+The output file is thus the input file enriched with information about 
+related items found in the selected repository/service.   
+
+The service should implement the following interface: 
+
+http://service_url/mass?targetMs=500&margin=1&marginUnit=ppm&output=txth   (txth means there is guaranteed to be a header line before the data)
+
+The output should be tab separated and should contain the following columns (in this order)
+db-name    molecular-formula    dbe    formula-weight    id    description
+
+
+'''
+import csv
+import sys
+import fileinput
+import urllib2
+import time
+from collections import OrderedDict
+
+__author__ = "Pieter Lukasse"
+__contact__ = "pieter.lukasse@wur.nl"
+__copyright__ = "Copyright, 2014, Plant Research International, WUR"
+__license__ = "Apache v2"
+
+def _process_file(in_xsv, delim='\t'):
+    '''
+    Generic method to parse a tab-separated file returning a dictionary with named columns
+    @param in_csv: input filename to be parsed
+    '''
+    data = list(csv.reader(open(in_xsv, 'rU'), delimiter=delim))
+    return _process_data(data)
+    
+def _process_data(data):
+    
+    header = data.pop(0)
+    # Create dictionary with column name as key
+    output = OrderedDict()
+    for index in xrange(len(header)):
+        output[header[index]] = [row[index] for row in data]
+    return output
+
+
+def _query_and_add_data(input_data, molecular_mass_col, repository_dblink, error_margin, margin_unit):
+    
+    '''
+    This method will iterate over the record in the input_data and
+    will enrich them with the related information found (if any) in the 
+    chosen repository/service
+    
+    # TODO : could optimize this with multi-threading, see also nice example at http://stackoverflow.com/questions/2846653/python-multithreading-for-dummies
+    '''
+    merged = []
+    
+    for i in xrange(len(input_data[input_data.keys()[0]])):
+        # Get the record in same dictionary format as input_data, but containing
+        # a value at each column instead of a list of all values of all records:
+        input_data_record = OrderedDict(zip(input_data.keys(), [input_data[key][i] for key in input_data.keys()]))
+        
+        # read the molecular mass :
+        molecular_mass = input_data_record[molecular_mass_col]
+        
+        
+        # search for related records in repository/service:
+        data_found = None
+        if molecular_mass != "": 
+            molecular_mass = float(molecular_mass)
+            
+            # 1- search for data around this MM:
+            query_link = repository_dblink + "/mass?targetMs=" + str(molecular_mass) + "&margin=" + str(error_margin) + "&marginUnit=" + margin_unit + "&output=txth"
+            
+            data_found = _fire_query_and_return_dict(query_link + "&_format_result=tsv")
+            data_type_found = "MM"
+        
+                
+        if data_found == None:
+            # If still nothing found, just add empty columns
+            extra_cols = ['', '','','','','']
+        else:
+            # Add info found:
+            extra_cols = _get_extra_info_and_link_cols(data_found, data_type_found, query_link)
+        
+        # Take all data and merge it into a "flat"/simple array of values:
+        field_values_list = _merge_data(input_data_record, extra_cols)
+    
+        merged.append(field_values_list)
+
+    # return the merged/enriched records:
+    return merged
+
+
+def _get_extra_info_and_link_cols(data_found, data_type_found, query_link):
+    '''
+    This method will go over the data found and will return a 
+    list with the following items:
+    - details of hits found :
+         db-name    molecular-formula    dbe    formula-weight    id    description
+    - Link that executes same query
+        
+    '''
+    
+    # set() makes a unique list:
+    db_name_set = []
+    molecular_formula_set = []
+    id_set = []
+    description_set = []
+    
+    
+    if 'db-name' in data_found:
+        db_name_set = set(data_found['db-name'])
+    elif '# db-name' in data_found:
+        db_name_set = set(data_found['# db-name'])    
+    if 'molecular-formula' in data_found:
+        molecular_formula_set = set(data_found['molecular-formula'])
+    if 'id' in data_found:
+        id_set = set(data_found['id'])
+    if 'description' in data_found:
+        description_set = set(data_found['description'])
+    
+    result = [data_type_found,
+              _to_xsv(db_name_set),
+              _to_xsv(molecular_formula_set),
+              _to_xsv(id_set),
+              _to_xsv(description_set),
+              #To let Excel interpret as link, use e.g. =HYPERLINK("http://stackoverflow.com", "friendly name"): 
+              "=HYPERLINK(\""+ query_link + "\", \"Link to entries found in DB \")"]
+    return result
+
+
+def _to_xsv(data_set):
+    result = ""
+    for item in data_set:
+        result = result + str(item) + "|"    
+    return result
+
+
+def _fire_query_and_return_dict(url):
+    '''
+    This method will fire the query as a web-service call and 
+    return the results as a list of dictionary objects
+    '''
+    
+    try:
+        data = urllib2.urlopen(url).read()
+        
+        # transform to dictionary:
+        result = []
+        data_rows = data.split("\n")
+        
+        # remove comment lines if any (only leave the one that has "molecular-formula" word in it...compatible with kazusa service):
+        data_rows_to_remove = []
+        for data_row in data_rows:
+            if data_row == "" or (data_row[0] == '#' and "molecular-formula" not in data_row):
+                data_rows_to_remove.append(data_row)
+                
+        for data_row in data_rows_to_remove:
+            data_rows.remove(data_row)
+        
+        # check if there is any data in the response:
+        if len(data_rows) <= 1 or data_rows[1].strip() == '': 
+            # means there is only the header row...so no hits:
+            return None
+        
+        for data_row in data_rows:
+            if not data_row.strip() == '':
+                row_as_list = _str_to_list(data_row, delimiter='\t')
+                result.append(row_as_list)
+        
+        # return result processed into a dict:
+        return _process_data(result)
+        
+    except urllib2.HTTPError, e:
+        raise Exception( "HTTP error for URL: " + url + " : %s - " % e.code + e.reason)
+    except urllib2.URLError, e:
+        raise Exception( "Network error: %s" % e.reason.args[1] + ". Administrator: please check if service [" + url + "] is accessible from your Galaxy server. ")
+
+def _str_to_list(data_row, delimiter='\t'):    
+    result = []
+    for column in data_row.split(delimiter):
+        result.append(column)
+    return result
+    
+    
+# alternative: ?    
+#     s = requests.Session()
+#     s.verify = False
+#     #s.auth = (token01, token02)
+#     resp = s.get(url, params={'name': 'anonymous'}, stream=True)
+#     content = resp.content
+#     # transform to dictionary:
+    
+    
+    
+    
+def _merge_data(input_data_record, extra_cols):
+    '''
+    Adds the extra information to the existing data record and returns
+    the combined new record.
+    '''
+    record = []
+    for column in input_data_record:
+        record.append(input_data_record[column])
+    
+    
+    # add extra columns
+    for column in extra_cols:
+        record.append(column)    
+    
+    return record  
+    
+
+def _save_data(data_rows, headers, out_csv):
+    '''
+    Writes tab-separated data to file
+    @param data_rows: dictionary containing merged/enriched dataset
+    @param out_csv: output csv file
+    '''
+
+    # Open output file for writing
+    outfile_single_handle = open(out_csv, 'wb')
+    output_single_handle = csv.writer(outfile_single_handle, delimiter="\t")
+
+    # Write headers
+    output_single_handle.writerow(headers)
+
+    # Write one line for each row
+    for data_row in data_rows:
+        output_single_handle.writerow(data_row)
+
+def _get_repository_URL(repository_file):
+    '''
+    Read out and return the URL stored in the given file.
+    '''
+    file_input = fileinput.input(repository_file)
+    try:
+        for line in file_input:
+            if line[0] != '#':
+                # just return the first line that is not a comment line:
+                return line
+    finally:
+        file_input.close()
+    
+
+def main():
+    '''
+    Query main function
+    
+    The input file can be any tabular file, as long as it contains a column for the molecular mass.
+    This column is then used to query against the chosen repository/service Database.   
+    '''
+    seconds_start = int(round(time.time()))
+    
+    input_file = sys.argv[1]
+    molecular_mass_col = sys.argv[2]
+    repository_file = sys.argv[3]
+    error_margin = float(sys.argv[4])
+    margin_unit = sys.argv[5]
+    output_result = sys.argv[6]
+
+    # Parse repository_file to find the URL to the service:
+    repository_dblink = _get_repository_URL(repository_file)
+    
+    # Parse tabular input file into dictionary/array:
+    input_data = _process_file(input_file)
+    
+    # Query data against repository :
+    enriched_data = _query_and_add_data(input_data, molecular_mass_col, repository_dblink, error_margin, margin_unit)
+    headers = input_data.keys() + ['SEARCH hits for ','SEARCH hits: db-names', 'SEARCH hits: molecular-formulas ',
+                                   'SEARCH hits: ids','SEARCH hits: descriptions', 'Link to SEARCH hits']
+
+    _save_data(enriched_data, headers, output_result)
+    
+    seconds_end = int(round(time.time()))
+    print "Took " + str(seconds_end - seconds_start) + " seconds"
+                      
+                      
+
+if __name__ == '__main__':
+    main()