Merge ~sergiodj/ubuntu/+source/telegraf:bug1916305-telegraf-conf into ~ubuntu-server/ubuntu/+source/telegraf:master

[Sergio Durigan Junior]

Fix for bug 1916305.

In a nutshell: after installing telegraf, it will always try to connect to an influxdb instance. This is because of the default configuration file shipped with it. When it fails, it generated *a lot* of pollution in the log files. Since we might not always have such an instance in the system, it makes sense to disable this by default. And given that, by design, telegraf must always have at least one output configured, this MP enables the prometheus_client output, which should be harmless and is actually a good thing to allow the user to verify whether things are running OK.

There's a build with the proposed change here:

https://launchpad.net/~sergiodj/+archive/ubuntu/telegraf-merge

[Bryce Harrington (bryce)]

Yeah I remember these changes when doing the LMA docs. Dropping the influxdb config makes sense.

In testing upgrading to this version from an existing installation will prompt the user to confirm the config change. However, it looks like we only introduced telegraf as of groovy, so the impact on users can probably be considered negligible.

Other than that, the installation seems to work ok.

autopkgtest has been running `test basic-outputs` for a while for me in lxc, but seems to be stuck. Did you successfully verify autopkgtest already?

I spotted a small text error in the changelog. I also have some phrasing suggestions but that you can take or leave as you wish. No need to re-review after fixing those, you can go ahead and just land.

review: Needs Fixing

[Sergio Durigan Junior (sergiodj)]

Thanks for the review, Bryce.

Indeed, the autopkgtest is hanging there. I submitted the MP before running it, and I should have waited. Anyway, I already know why it's not finishing: if you look at the test, the initial part of it is actually doing exactly what this MP is proposing, so the fix is to actually remove this part, and everything runs nicely.

I thank you for spotting the (rather dumb) mistake in the changelog entry, and for the Bug-Ubuntu suggestion: I've fixed everything now.

I went ahead and pushed + uploaded everything:

$ gbp tag
gbp:info: Tagging Debian package 1.17.2+ds1-0ubuntu2 as debian/1.17.2+ds1-0ubuntu2 in git
$ gbp push
gbp:info: Pushing debian/1.17.2+ds1-0ubuntu2 to origin
gbp:info: Pushing upstream/1.17.2+ds1 to origin
gbp:info: Pushing refs/heads/master to origin:refs/heads/master
gbp:info: Pushing refs/heads/upstream to origin:refs/heads/upstream
gbp:info: Pushing refs/heads/pristine-tar to origin:refs/heads/pristine-tar
$ dput telegraf_1.17.2+ds1-0ubuntu2_source.changes
Trying to upload package to ubuntu
Checking signature on .changes
gpg: /home/sergio/work/telegraf/telegraf_1.17.2+ds1-0ubuntu2_source.changes: Valid signature from 106DA1C8C3CBBF14
Checking signature on .dsc
gpg: /home/sergio/work/telegraf/telegraf_1.17.2+ds1-0ubuntu2.dsc: Valid signature from 106DA1C8C3CBBF14
Uploading to ubuntu (via ftp to upload.ubuntu.com):
  Uploading telegraf_1.17.2+ds1-0ubuntu2.dsc: done.
  Uploading telegraf_1.17.2+ds1-0ubuntu2.debian.tar.xz: done.
  Uploading telegraf_1.17.2+ds1-0ubuntu2_source.buildinfo: done.
  Uploading telegraf_1.17.2+ds1-0ubuntu2_source.changes: done.
Successfully uploaded packages.

diff --git a/debian/changelog b/debian/changelog
index 3669daf..dcf24af 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,16 @@
+telegraf (1.17.2+ds1-0ubuntu2) hirsute; urgency=medium
+
+  * d/p/adjust-etc-telegraf.conf.patch: Adjust /etc/telegraf.conf.
+    Change telegraf's default configuration to not attempt connecting to
+    an influxdb instance, as it's not required for installation and thus
+    may not be present. (LP: #1916305)
+  * d/t/basic-outputs: Update and simplify test preparation.
+    With the change in the configuration file, there is no more need to
+    comment out the influxdb output nor to add the prometheus_client
+    output.
+
+ -- Sergio Durigan Junior <[e-mail]>  Fri, 19 Feb 2021 23:46:34 -0500
+
 telegraf (1.17.2+ds1-0ubuntu1) hirsute; urgency=medium
 
   * d/repack-telegraf-with-vendor.sh: Fix "trap" instruction.
diff --git a/debian/patches/adjust-etc-telegraf.conf.patch b/debian/patches/adjust-etc-telegraf.conf.patch
new file mode 100644
index 0000000..e424fa4
--- /dev/null
+++ b/debian/patches/adjust-etc-telegraf.conf.patch
@@ -0,0 +1,48 @@
+From: Sergio Durigan Junior <[e-mail]>
+Date: Fri, 19 Feb 2021 18:00:08 -0500
+Subject: Adjust /etc/telegraf.conf
+
+Change telegraf's default configuration to not attempt connecting to
+an influxdb instance, as it's not required for installation and thus
+may not be present.
+
+Bug-Ubuntu: https://bugs.launchpad.net/ubuntu/+source/telegraf/+bug/1916305
+Forwarded: not-needed
+---
+ etc/telegraf.conf | 8 ++++----
+ 1 file changed, 4 insertions(+), 4 deletions(-)
+
+diff --git a/etc/telegraf.conf b/etc/telegraf.conf
+index 9d52d0a..7efb747 100644
+--- a/etc/telegraf.conf
++++ b/etc/telegraf.conf
+@@ -102,7 +102,7 @@
+ 
+ 
+ # Configuration for sending metrics to InfluxDB
+-[[outputs.influxdb]]
++#[[outputs.influxdb]]
+   ## The full HTTP or UDP URL for your InfluxDB instance.
+   ##
+   ## Multiple URLs can be specified for a single cluster, only ONE of the
+@@ -1203,9 +1203,9 @@
+ 
+ 
+ # # Configuration for the Prometheus client to spawn
+-# [[outputs.prometheus_client]]
++[[outputs.prometheus_client]]
+ #   ## Address to listen on
+-#   listen = ":9273"
++    listen = ":9273"
+ #
+ #   ## Metric version controls the mapping from Telegraf metrics into
+ #   ## Prometheus format.  When using the prometheus input, use the same value in
+@@ -1213,7 +1213,7 @@
+ #   ##
+ #   ##   example: metric_version = 1; deprecated in 1.13
+ #   ##            metric_version = 2; recommended version
+-#   # metric_version = 1
++    metric_version = 2
+ #
+ #   ## Use HTTP Basic Authentication.
+ #   # basic_username = "Foo"
diff --git a/debian/patches/series b/debian/patches/series
index 74d79c4..7de5f2c 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -1 +1,2 @@
 adjust-service-user.patch
+adjust-etc-telegraf.conf.patch
diff --git a/debian/tests/basic-outputs b/debian/tests/basic-outputs
index fa29a75..0d844d1 100644
--- a/debian/tests/basic-outputs
+++ b/debian/tests/basic-outputs
@@ -7,15 +7,8 @@ set -e
 set -x
 set -o pipefail
 
-# Disable the influxdb output plugin since we won't be using it.
-sed -i 's@^\(\[\[outputs.influxdb\]\]\)$@#\1@' /etc/telegraf/telegraf.conf
-
 # Enable some output plugins.
 cat >> /etc/telegraf/telegraf.conf << EOF
-[[outputs.prometheus_client]]
-  listen = "127.0.0.1:9273"
-  metric_version = 2
-
 [[outputs.http]]
   url = "http://127.0.0.1:8080/"
 EOF