Stumped by regular expression

Question

Requirement: build a health Check to send an api url call to server and parse the return value for key indicators.&nbsp;URL: rldimedas1.tcbna.net/rest/apigateway/health/all&nbsp;Crafted Send String: GET /rest/apigateway/health/all HTTP/1.1
Host: rldimedas1.tcbna.net
Connection: Close

&nbsp;User name and password required: DEVF5Inside / &lt;password&gt;&nbsp;Expected return to be parsed:&nbsp;{&nbsp;&nbsp;"status": "green",&nbsp;&nbsp;"elasticsearch": {&nbsp;&nbsp;&nbsp;&nbsp;"cluster_name": "DEV_EventDataStore",&nbsp;&nbsp;&nbsp;&nbsp;"status": "green",&nbsp;&nbsp;&nbsp;&nbsp;"number_of_nodes": "2",&nbsp;&nbsp;&nbsp;&nbsp;"number_of_data_nodes": "2",&nbsp;&nbsp;&nbsp;&nbsp;"timed_out": "false",&nbsp;&nbsp;&nbsp;&nbsp;"active_shards": "388",&nbsp;&nbsp;&nbsp;&nbsp;"initializing_shards": "0",&nbsp;&nbsp;&nbsp;&nbsp;"unassigned_shards": "0",&nbsp;&nbsp;&nbsp;&nbsp;"task_max_waiting_in_queue_millis": "0",&nbsp;&nbsp;&nbsp;&nbsp;"port_9240": "ok",&nbsp;&nbsp;&nbsp;&nbsp;"response_time_ms": "16"&nbsp;&nbsp;},&nbsp;&nbsp;"is": {&nbsp;&nbsp;&nbsp;&nbsp;"status": "green",&nbsp;&nbsp;&nbsp;&nbsp;"diskspace": {&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"status": "up",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"free": "99419619328",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"inuse": "152539549696",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"threshold": "25195916902",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"total": "251959169024"&nbsp;&nbsp;&nbsp;&nbsp;},&nbsp;&nbsp;&nbsp;&nbsp;"memory": {&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"status": "up",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"freemem": "2668806528",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"maxmem": "3817865216",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"threshold": "368102604",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"totalmem": "3681026048"&nbsp;&nbsp;&nbsp;&nbsp;},&nbsp;&nbsp;&nbsp;&nbsp;"servicethread": {&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"status": "up",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"avail": "286",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"inuse": "14",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"max": "300",&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;"threshold": "30"&nbsp;&nbsp;&nbsp;&nbsp;},&nbsp;&nbsp;&nbsp;&nbsp;"response_time_ms": "103"&nbsp;&nbsp;},&nbsp;&nbsp;"terracotta": {&nbsp;&nbsp;&nbsp;&nbsp;"status": "green",&nbsp;&nbsp;&nbsp;&nbsp;"nodes": "2",&nbsp;&nbsp;&nbsp;&nbsp;"healthy_nodes": "2",&nbsp;&nbsp;&nbsp;&nbsp;"response_time_ms": "67"&nbsp;&nbsp;}}&nbsp;3 Key Indicators of healthy Services:&nbsp;#1 "elasticsearch": {&nbsp;&nbsp;&nbsp;&nbsp;"cluster_name": "DEV_EventDataStore",&nbsp;&nbsp;&nbsp;&nbsp;"status": "green",&nbsp;#2 "is": {&nbsp;&nbsp;&nbsp;&nbsp;"status": "green",&nbsp;#3 "terracotta": {&nbsp;&nbsp;&nbsp;&nbsp;"status": "green",&nbsp;&nbsp;I would think it was possible to craft the received string parse to check for all 2 key indicators so I do not have to create 3 separate health checks.&nbsp;I have tried just checking for the first indication by following suggestion in DevCentral but is did not work:&nbsp;\"elasticsearch\": \{\"cluster_name\": \"DEV_EventDataStore\",\"status\": \"green\",&nbsp;This solution is complicated by all 3 indicators being the same syntax: "status": "green"&nbsp;I think there might be an issue with my GET string as well because the Monitor log only shows "200 OK" as the response from the server.&nbsp;When I change the receive string to only elasticsearch, it passes.&nbsp;Any Help Here?

richard_grigsb1 · Answer

Issue resolved.&nbsp;I discovered that the "Type" and "parent monitor" were set to "HTTPS" but SSL Profile was left at "NONE".  I selected a generic ssl profile and the health check started functioning. &nbsp;Here is what I end up with for the unique/per server in the pool/heath check.&nbsp;Send String: GET /rest/apigateway/health/all HTTP/1.1
Host:&nbsp;rldimedas1.tcbna.net
Connection: Close

Receive String: elasticsearch.*cluster_name.*DEV_EventDataStore.*status.*green.*number_of_nodes.*status.*green.*diskspace.*terracotta.*status.*green.*nodes&nbsp;The additional items in the receive string parse are so the F5 does not match subsequent &nbsp;"status": "green" occurrences in the reply.&nbsp;Thank You for your responses.&nbsp;I am moving forward with the "monitoring server platform" idea that will provide an UP/DOWN HTML page for the F5 to check.&nbsp;

simon_blakely · Answer

I always start my regex development at &nbsp;regex101.com &nbsp;(\"elasticsearch\")(.*)(
\B)(\s*.*
\B)(\s*\"status\": \"green\")&nbsp;matches the first stanza.&nbsp;It gets harder from there ...

jrahm · Answer

Could you use an external monitor so you can parse the json return data more cleanly than with REGEX? in python, that would be pretty simple:from sys import stdout
resp = '''your json response string'''
if resp['elasticsearch']['status'] == 'green' and resp['is']['status'] == 'green' and resp['terracotta']['status'] == 'green':
    stdout.write('UP')
else:
    stdout.write('DOWN')
    
UPYou can find a full python external monitor sample here in the codeshare for RADIUS that you could modify to meet your needs.

richard_grigsb1 · Answer

Could the issue actually be in the formatting of my GET string?&nbsp;Here is the URL the DEV OPS Team gave me:HTTPS:// rldimedas1.tcbna.net/rest/apigateway/health/all&nbsp;Here is how I formatted the Send String:GET /rest/apigateway/health/all HTTP/1.1
Host: rldimedas1.tcbna.net
Connection: Close

&nbsp;This request requires a username and password so they have been entered

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Stumped by regular expression

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