new: usr: NO-JIRA: Sample code for submitting Presto command and down…

…loading result (#216)

example/qubole_presto_api_example.py

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+
+"""
+This is the sample code used for submitting a Presto query (PrestoCommand) and getting the result back to local file.
+Similar way can be followed for HiveCommand etc.
+"""
+
+import sys
+import string
+from ConfigParser import SafeConfigParser
+from qds_sdk.qubole import Qubole
+from qds_sdk.commands import *
+import boto
+import time
+
+
+# Used for generating file name to download the result
+def get_random_filename(size=10):
+    return "/tmp/result_" + str(int(time.time())) + ".tsv"
+
+# Returning content from the file 
+def get_content(filename):
+    with open(filename, 'r') as content_file:
+        content = content_file.read()
+    return content
+
+# Executing given query
+def execute_query(query):
+    if query is None or query == "":
+        return None
+    cmd = PrestoCommand.create(query=query)
+    query_id = str(cmd.id)
+    print "Starting Command with id: " + query_id + "\nProgress: =>",
+    while not PrestoCommand.is_done(cmd.status):
+        print "\b=>",
+        cmd = PrestoCommand.find(cmd.id)
+        time.sleep(5)
+    print cmd.get_log()
+    if PrestoCommand.is_success(cmd.status):
+        print "\nCommand Executed: Completed successfully"
+    else:
+        print "\nCommand Executed: Failed!!!. The status returned is: " + str(cmd.status)
+    return cmd
+
+# Downloading the result
+def get_results(command):
+    if command is None:
+        return None
+    filename = get_random_filename(10)
+    print filename
+    fp = open(filename, 'w')
+    command.get_results(fp, delim="\n")
+    print "Starting Result fetch with Command id: " + str(command.id) + "\nProgress: =>",
+    while not PrestoCommand.is_done(command.status):
+        print "\b=>",
+        time.sleep(5)
+    if PrestoCommand.is_success(command.status):
+        print "\nCommand Executed: Results fetch completed successfully"
+    else:
+        print "\nCommand Executed: Result fetch for original command " + str(command.id) + "Failed!!!. The status returned is: " + str(command.status)
+    fp.close()
+    content = get_content(filename)
+    return content
+
+
+if __name__ == '__main__':
+    # Stting API token
+    Qubole.configure(api_token='YOUR-QUBOLE-API-TOKEN')
+    get_results(execute_query("select * from  default.cities limit 100;"))