586178b4ab
Essentially, just don't try to set a status code and send any error message in the body once metrics gathering has succeeded. At that point, the most likely reason for errors is anyway that the client has disconnected, in which sending an error is moot. The other possible reason for an error is a problem during metrics encoding. This is unlikely to happen (it's a coding error here in client_golang in any case), and if it is happening, the odds are we have already sent something to the ResponseWriter, which means we cannot set a status code anymore. The doc comment for HTTPErrorOnError now describes these circumstances explicitly and recommends to set a logger to report that kind of error. This should fix the reason for the infamous `superfluous response.WriteHeader call` message. Signed-off-by: beorn7 <beorn@grafana.com> |
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api | ||
examples | ||
prometheus | ||
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CHANGELOG.md | ||
CONTRIBUTING.md | ||
Dockerfile | ||
LICENSE | ||
MAINTAINERS.md | ||
Makefile | ||
Makefile.common | ||
NOTICE | ||
README.md | ||
VERSION | ||
go.mod | ||
go.sum |
README.md
Prometheus Go client library
This is the Go client library for Prometheus. It has two separate parts, one for instrumenting application code, and one for creating clients that talk to the Prometheus HTTP API.
This library requires Go1.9 or later. The minimum required patch releases for older Go versions are Go1.9.7 and Go1.10.3.
Important note about releases and stability
This repository generally follows Semantic Versioning. However, the API client in prometheus/client_golang/api/… is still considered experimental. Breaking changes of the API client will not trigger a new major release. The same is true for selected other new features explicitly marked as EXPERIMENTAL in CHANGELOG.md.
Features that require breaking changes in the stable parts of the repository are being batched up and tracked in the v2 milestone. The v2 development happens in a separate branch for the time being. v2 releases off that branch will happen once sufficient stability is reached. In view of the widespread use of this repository, v1 and v2 will coexist for a while to enable a convenient transition.
Instrumenting applications
The
prometheus
directory
contains the instrumentation library. See the
guide on the Prometheus
website to learn more about instrumenting applications.
The
examples
directory
contains simple examples of instrumented code.
Client for the Prometheus HTTP API
The
api/prometheus
directory
contains the client for the
Prometheus HTTP API. It allows you
to write Go applications that query time series data from a Prometheus
server. It is still in alpha stage.
Where is model
, extraction
, and text
?
The model
packages has been moved to
prometheus/common/model
.
The extraction
and text
packages are now contained in
prometheus/common/expfmt
.
Contributing and community
See the contributing guidelines and the Community section of the homepage.