Handle more error scenarios for promql_api

Handle more error scenarios for promql
and improve README.Added copy rights

Change-Id: Idb3ac7e2aea6fe3e6df069f63e63b2a5208f96d1
Issue-ID: ONAPARC-452
Signed-off-by: Rajamohan Raj <rajamohan.raj@intel.com>

2 files changed, 77 insertions, 24 deletions

diff --git a/vnfs/DAaaS/lib/promql_api/README.md b/vnfs/DAaaS/lib/promql_api/README.md
index de64fe0b..f2d45951 100644
--- a/vnfs/DAaaS/lib/promql_api/README.md
+++ b/vnfs/DAaaS/lib/promql_api/README.md
@@ -1,12 +1,12 @@
 ## What does this API do ?
-This api as of now provides a function which takes in a lits of 'LABELS' of prometheus
+This api as of now provides a function which takes in a list of 'QUERY_STRINGs' with respect to prometheus
 and returns the corresponding result_sets in a list.
 
 For eg:
-If the labels is
+If the QUERY_STRING is
 
 ```
-LABELS = ['irate(collectd_cpufreq{exported_instance="otconap7",cpufreq="1"}[2m])']
+QUERY_STRING = ['irate(collectd_cpufreq{exported_instance="otconap7",cpufreq="1"}[2m])']
 ```
 
 The return is:
@@ -22,7 +22,7 @@ The return is:
              'service': 'collectd'},
   'value': [1559177169.415, '119727200']}]
 ```
-
+i
 ## How to use this API ?
 
 ```
@@ -35,13 +35,13 @@ from promql_api.prom_ql_api import query
 ```
 
 ```
-3. have a global or local variable as 'LABELS'
-LABELS = ['irate(collectd_cpufreq{exported_instance="otconap7",cpufreq="1"}[2m])']
+3. have a global or local variable as 'QUERY_STRING'
+QUERY_STRING = ['irate(collectd_cpufreq{exported_instance="otconap7",cpufreq="1"}[2m])']
 ```
 
 ```
 4. Store the result set in a list:
-list_of_result_sets = query(LABELS)
+list_of_result_sets = query(QUERY_STRING)
 ```
 
 ## Troubleshooting tips
@@ -49,6 +49,7 @@ list_of_result_sets = query(LABELS)
 * Check the sample file - sample_promql_query.py in the repo ( sample-apps/m3db_promql)
 * Make sure the file "__init__.py" is present in promql_api directory after you copy the directory.
 * Make sure environment variables like "DATA_ENDPOINT" are correctly set.
+* For custom and advanced querying https://prometheus.io/docs/prometheus/latest/querying/api/
 * Logs are generated in the directory where the query function is called.
 * sample log file - promql_api.log
 
@@ -63,3 +64,24 @@ list_of_result_sets = query(LABELS)
  05-30-2019 08:47:53PM ::prom_ql_api.py :: query :: INFO :: ::::::::::RESULTS:::::::::::::                           irate(collectd_cpufreq{exported_instance="otconap7",cpufreq="1"}[2m])
  05-30-2019 08:47:53PM ::prom_ql_api.py :: query :: INFO :: {'metric': {'cpufreq': '1', 'endpoint': 'collectd-       prometheus', 'exported_instance': 'otconap7', 'instance': '172.25.103.1:9103', 'job': 'collectd', 'namespace':      'edge1', 'pod': 'plundering-liger-collectd-wz7xg', 'service': 'collectd'}, 'value': [1559249299.084, '236300']}
  ```
+
+ * Tested Error scenario: Configure QUERY_STRING as :
+ ```
+ QUERY_STRING = ['irate(collectd_cpufreq{exported_instance="otconap7", cpufreq="1"}[2m])', 'collectd_cpu_percent{job="collectd" exported_instance="an11-31"}[1m]']
+ ```
+ O/P :
+ ```
+ Check logs..HTTP error occurred: 400 Client Error: Bad Request for url: http://172.25.103.1:30090/api/v1/query?query=collectd_cpu_percent%7Bjob%3D%22collectd%22+exported_instance%3D%22an11-31%22%7D%5B1m%5D
+[{'metric': {'cpufreq': '1',
+             'endpoint': 'collectd-prometheus',
+             'exported_instance': 'otconap7',
+             'instance': '172.25.103.1:9103',
+             'job': 'collectd',
+             'namespace': 'edge1',
+             'pod': 'plundering-liger-collectd-wz7xg',
+             'service': 'collectd'},
+  'value': [1559343866.631, '119798600']}]
+{'error': 'parse error at char 37: missing comma before next identifier '
+          '"exported_instance"',
+ 'errorType': 'bad_data'}
+```
diff --git a/vnfs/DAaaS/lib/promql_api/prom_ql_api.py b/vnfs/DAaaS/lib/promql_api/prom_ql_api.py
index 970d2416..8a5ce508 100644
--- a/vnfs/DAaaS/lib/promql_api/prom_ql_api.py
+++ b/vnfs/DAaaS/lib/promql_api/prom_ql_api.py
@@ -1,3 +1,21 @@
+# -------------------------------------------------------------------------
+#   Copyright (c) 2019 Intel Corporation Intellectual Property
+#
+#   Licensed under the Apache License, Version 2.0 (the "License");
+#   you may not use this file except in compliance with the License.
+#   You may obtain a copy of the License at
+#
+#       http://www.apache.org/licenses/LICENSE-2.0
+#
+#   Unless required by applicable law or agreed to in writing, software
+#   distributed under the License is distributed on an "AS IS" BASIS,
+#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#   See the License for the specific language governing permissions and
+#   limitations under the License.
+#
+# -------------------------------------------------------------------------
+
+
 from __future__ import print_function
 from os import environ
 import logging
@@ -5,12 +23,12 @@ import requests
 from requests.exceptions import HTTPError
 
 
-
 API_VERSION = '/api/v1/query'
 LIST_OF_ENV_VARIABLES = ["DATA_ENDPOINT"]
 MAP_ENV_VARIABLES = dict()
 LOG = logging.getLogger(__name__)
 
+
 def set_log_config():
     logging.basicConfig(format='%(asctime)s ::%(filename)s :: %(funcName)s :: %(levelname)s :: %(message)s',
                     datefmt='%m-%d-%Y %I:%M:%S%p',
@@ -32,12 +50,12 @@ def load_and_validate_env_vars(list_of_env_vars):
             raise KeyError("Env variable: {} not found ! ".format(env_var.upper()))
 
 
-def query(LABELS):
+def query(QUERY_STRING):
     """
     Input parameters:
-        LABELS : a list of the LABELS like ['irate(collectd_cpufreq{exported_instance="otconap7",cpufreq="1"}[2m])']
+        QUERY_STRING : a list of the query strings like ['irate(collectd_cpufreq{exported_instance="otconap7",cpufreq="1"}[2m])']
     Return:
-        returns a list of  result sets of different labels.
+        returns a list of  result sets corresponding to each of the query strings..
         SAMPLE O/P:
         [{'metric': {'cpufreq': '1',
              'endpoint': 'collectd-prometheus',
@@ -59,24 +77,37 @@ def query(LABELS):
     list_of_substrings.append(API_VERSION)
     url = ''.join(list_of_substrings)
 
-    for each_label in LABELS:
-        params_map['query'] = each_label
+    for each_query_string in QUERY_STRING:
+        params_map['query'] = each_query_string
         try:
             LOG.info('API request::: URL: {} '.format(url))
             LOG.info('API request::: params: {} '.format(params_map))
             response = requests.get(url, params=params_map)
-            response.raise_for_status()
+            response.raise_for_status() # This might raise HTTPError which is handled in except block
         except HTTPError as http_err:
-            print(f'HTTP error occurred: {http_err}')
-            return None
+            if response.json()['status'] == "error":
+                LOG.error("::::ERROR OCCURED::::")
+                LOG.error("::::ERROR TYPE:::: {}".format(response.json()['errorType']))
+                LOG.error("::::ERROR:::: {}".format(response.json()['error']))
+                list_of_result_sets.append(dict({'error':response.json()['error'],
+                                                'errorType' : response.json()['errorType']}))
+            print(f'Check logs..HTTP error occurred: {http_err}')
+
         except Exception as err:
-            print(f'Other error occurred: {err}')
-            return None
-        else:
+            print(f'Check logs..Other error occurred: {err}')
 
-            results = response.json()['data']['result']
-            LOG.info('::::::::::RESULTS::::::::::::: {}'.format(each_label))
-            for each_result in results:
-                LOG.info(each_result)
-            list_of_result_sets.append(results)
+        else:
+            if response.json()['status'] == "error":
+                LOG.error("::::ERROR OCCURED!::::")
+                LOG.error("::::ERROR TYPE:::: {}".format(response.json()['errorType']))
+                LOG.error("::::ERROR:::: {}".format(response.json()['error']))
+                list_of_result_sets.append(response.json()['error'])
+                list_of_result_sets.append(dict({'error':response.json()['error'],
+                                                'errorType' : response.json()['errorType']}))
+            else:
+                results = response.json()['data']['result']
+                LOG.info('::::::::::RESULTS::::::::::::: {}'.format(each_query_string))
+                for each_result in results:
+                    LOG.info(each_result)
+                list_of_result_sets.append(results)
     return list_of_result_sets