PromQL api for query

Initial commit for promQL query api and sample app for using the api

Change-Id: Id9c5d95f621edbb14b2eba7493c968c138d2d02a
Issue-ID: ONAPARC-452
Signed-off-by: Rajamohan Raj <rajamohan.raj@intel.com>

4 files changed, 145 insertions, 0 deletions

diff --git a/vnfs/DAaaS/applications/m3db_promql/promql_api/README.md b/vnfs/DAaaS/applications/m3db_promql/promql_api/README.md
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+## What does this API do ?
+This api as of now provides a function which takes in a lits of 'LABELS' of prometheus
+and returns the corresponding result_sets in a list.
+
+For eg:
+If the labels is
+
+```
+LABELS = ['irate(collectd_cpufreq{exported_instance="otconap7",cpufreq="1"}[2m])']
+```
+
+The return is:
+
+```
+[{'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': [1559177169.415, '119727200']}]
+```
+
+## How to use this API ?
+
+```
+1. Copy the directory 'promql_api' to your working directory. 
+```
+
+```
+2. Import the API function: query_m3db
+from promql_api.prom_ql_api import query_m3db
+```
+
+```
+3. have a global or local variable as 'LABELS'
+LABELS = ['irate(collectd_cpufreq{exported_instance="otconap7",cpufreq="1"}[2m])']
+```
+
+```
+4. Store the result set in a list:
+list_of_result_sets = query_m3db(LABELS)
+```
+
+## How to troubleshoot ?
+
+* Check the sample file - sample_promql_query.py in the repo.
+* Make sure the file __init__.py is present in promql_api directory after you copy the directory.
diff --git a/vnfs/DAaaS/applications/m3db_promql/promql_api/__init__.py b/vnfs/DAaaS/applications/m3db_promql/promql_api/__init__.py
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+++ b/vnfs/DAaaS/applications/m3db_promql/promql_api/__init__.py
diff --git a/vnfs/DAaaS/applications/m3db_promql/promql_api/prom_ql_api.py b/vnfs/DAaaS/applications/m3db_promql/promql_api/prom_ql_api.py
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+++ b/vnfs/DAaaS/applications/m3db_promql/promql_api/prom_ql_api.py
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+from __future__ import print_function
+from os import environ
+import logging
+import sysconfig
+import requests
+from requests.exceptions import HTTPError
+
+
+#LABELS = [ 'irate(http_requests_total{code="200"}[1m])', 'collectd_cpu_percent{job="collectd", exported_instance="an11-31"}[1m]' ]
+#LABELS = ['irate(collectd_cpufreq{exported_instance="otconap7",cpufreq="1"}[2m])', 'go_info']
+API_VERSION = '/api/v1/query'
+LIST_OF_ENV_VARIABLES = ["PROMETHEUS_SERVER_URL"]
+MAP_ENV_VARIABLES = dict()
+#MAP_ENV_VARIABLES['PROMETHEUS_SERVER_URL']='http://172.25.103.1:30090' #to be deleted
+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',
+                    level=logging.DEBUG, 
+                    filename='promql_api.log',
+                    filemode='w')
+    LOG.info("Set the log configs.")
+
+
+def load_and_validate_env_vars(list_of_env_vars):
+    LOG.info("Loading the env variables ...")
+    for env_var in list_of_env_vars:
+        if env_var in environ:
+            LOG.info("Found env variable: {} ".format(env_var.upper()))
+            MAP_ENV_VARIABLES[env_var.upper()] = environ.get(env_var)
+        else:
+            #MAP_ENV_VARIABLES['PROMETHEUS_SERVER_URL']='http://172.25.103.1:30090' # to be deleted
+            LOG.error("Env var: {} not found ! ".format(env_var.upper()))
+            raise KeyError("Env variable: {} not found ! ".format(env_var.upper()))
+
+
+def query_m3db(LABELS):
+    """
+    Input parameters:
+        LABELS : a list of the LABELS
+    Return:
+        returns a list of  result sets of different labels
+    """
+
+    LOG.info("Forming the get request ...")
+    list_of_substrings = []
+    params_map = {}
+    list_of_result_sets = []
+    list_of_substrings.append(MAP_ENV_VARIABLES['PROMETHEUS_SERVER_URL'])
+    list_of_substrings.append(API_VERSION)
+    url = ''.join(list_of_substrings)
+    
+    for each_label in LABELS:
+        params_map['query'] = each_label
+        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()
+        except HTTPError as http_err:
+            print(f'HTTP error occurred: {http_err}')
+            return None  
+        except Exception as err:
+            print(f'Other error occurred: {err}')
+            return None 
+        else:
+            
+            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)
+    return list_of_result_sets
+
+
+# def main():
+#     set_log_config()
+#     load_and_validate_env_vars(LIST_OF_ENV_VARIABLES)
+#     query_m3db(LABELS)
+
+# if __name__ == "__main__":
+#     main()
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diff --git a/vnfs/DAaaS/applications/m3db_promql/sample_promql_query.py b/vnfs/DAaaS/applications/m3db_promql/sample_promql_query.py
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+++ b/vnfs/DAaaS/applications/m3db_promql/sample_promql_query.py
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+from promql_api.prom_ql_api import query_m3db
+import pprint
+
+LABELS = ['irate(collectd_cpufreq{exported_instance="otconap7",cpufreq="1"}[2m])']
+
+def main():
+    list_of_result_sets = query_m3db(LABELS)
+    for each_result in list_of_result_sets:
+        pprint.pprint(each_result)
+
+if __name__ == "__main__":
+     main()
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