InfluxDB no longer parsing Grafana queries #91

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The problem

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Last night InfluxDB stopped parsing the queries sent by Grafana, without anything changed to HA/Grafana/InfluxDB. Has worked perfectly for several months.

What is still working?

• InfluxDB is still filling with HA data
• Using Chronograf from within HA, connection to InfluxDB is ok, I can query the DB and view results
• InfluxDB & Grafana start without errors, no errors in Add-In logs and Core logs in HA

What no longer working?

• All Grafana queries to InfluxDB throw errors that suggest the HTTP GET requests are not parsed

Environment

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• Home Assistant Core release with the issue: 0.115.6
• Last working Home Assistant Core release (if known): 0.115.6
• Operating environment (OS/Container/Supervised/Core): Supervised
• Integration causing this issue: InfluxDB
• Link to integration documentation on our website:

Problem-relevant configuration.yaml

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Traceback/Error logs

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When creating a new dashboard, Grafana immediately throws the following error:

InfluxDB Error: error parsing query: found %, expected identifier, string, number, bool at line 1, char 13

Char 13 is the % right after mean( in the query field Corresponding request in the Grafana Add-In logs:

[07/Oct/2020:10:49:51 +0200] 400 185.160.220.41, 172.30.32.1(172.30.32.2) GET /api/datasources/proxy/1/query?db=ha&q=SELECT+mean(%2522value%2522)+FROM+%2522measurement%2522+WHERE+time+%253E%253D+now()+-+6h+GROUP+BY+time(20s)+fill(null)&epoch=ms HTTP/1.1 (Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/85.0.4183.121 Safari/537.36)

When adding a new InfluxDB connection to Grafana, after removing the existing connection (following the configuration steps in the documentation)

InfluxDB Error: error parsing query: found %, expected identifier at line 1, char 28

Char 28 is the % right after +on+ in the query field Corresponding request in the Grafana Add-In logs:

[07/Oct/2020:10:54:19 +0200] 400 185.160.220.41, 172.30.32.1(172.30.32.2) GET /api/datasources/proxy/1/query?db=ha&q=SHOW+RETENTION+POLICIES+on+%2522ha%2522&epoch=ms HTTP/1.1 (Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/85.0.4183.121 Safari/537.36)

Additional information

It seems to me that InfluxDB is no longer correctly parsing the URL ASCII encoding. Reinstall of Grafana in HA yielded no results. Reinstall of InfluxDB was not yet tried, fear of losing all the data.