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krajorama
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Oct 7, 2025
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There's more escaping schemes https://prometheus.io/docs/instrumenting/escaping_schemes/
If, as you say, prom2json doesn't actually care about the names, why single out utf-8? Might as well enumerate the possible values in the option ?
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True. It didn't occur to me that people would like to pick other schemes (just that we cannot just make utf-8 the default). But you are right, maybe some people really want a particular escaping in their JSON. Will update. |
ywwg
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Oct 7, 2025
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All addressed. PHAL. |
Due to its simplistic design, prom2json has always tolerated any characters in metric and label names. (It does not validate anything, just puts strings into JSON objects…) However, a compliant scrape target will only serve unescaped UTF-8 in names if asked to do so. This commit adds a CLI option to add the 'escaping=SCHEME' parameter in content negotiation. We cannot set this option to 'allow-utf-8' by default without a major release because users might depend on the default (underscore) escaping. I implemented this in a slightly clunky way to not change the library API (although we use semver for the user API, not the library API here – I still thought we can be nice at a relatively small price). Signed-off-by: beorn7 <beorn@grafana.com>
krajorama
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Oct 14, 2025
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Due to its simplistic design, prom2json has always tolerated any characters in metric and label names. (It does not validate anything, just puts strings into JSON objects…)
However, a compliant scrape target will only serve unescaped UTF-8 in names if asked to do so. This commit adds a CLI option to make prom2json ask for it.
We cannot set this option by default without a major release because users might depend on the escaping.
I implemented this in a slightly clunky way to not change the library API (although we use semver for the user API, not the library API here – I still thought we can be nice at a relatively small price).