diskimage-builder/elements/cloud-init-datasources
Ian Wienand 36b59c001c Standarise tracing for scripts
There is a wide variety of tracing options through the various shell
scripts.  Some use "set -eux", others explicity set xtrace and others
do nothing.  There is a "-x" option to bin/disk-image-create but it
doesn't flow down to the many scripts it calls.

This adds a global integer variable set by disk-image-create
DIB_DEBUG_TRACE.  All scripts have a stanza added to detect this and
turn on tracing.  Any other tracing methods are rolled into this.  So
the standard header is

---
if [ "${DIB_DEBUG_TRACE:-0}" -gt 0 ]; then
    set -x
fi
set -eu
set -o pipefail
---

Multiple -x options can be specified to dib-create-image, which
increases the value of DIB_DEBUG_TRACE.  If script authors feel their
script should only trace at higher levels, they should modify the
"-gt" value.  If they feel it should trace by default, they can modify
the default value also.

Changes to pachset 16 : scripts which currently trace themselves by
default have retained this behaviour with DIB_DEBUG_TRACE defaulting
to "1".  This was done by running [1] on patch set 15.  See the thread
beginning at [2]

dib-lint is also updated to look for the variable being matched.

[1] https://gist.github.com/ianw/71bbda9e6acc74ccd0fd
[2] http://lists.openstack.org/pipermail/openstack-dev/2014-November/051575.html

Change-Id: I6c5a962260741dcf6f89da9a33b96372a719b7b0
2015-02-12 10:41:32 +11:00
..
install.d Standarise tracing for scripts 2015-02-12 10:41:32 +11:00
README.rst Create docs site containing element READMEs 2015-02-10 11:45:35 -08:00

cloud-init-datasources

Configures cloud-init to only use an explicit list of data sources.

Cloud-init contains a growing collection of data source modules and most are enabled by default. This causes cloud-init to query each data source on first boot. This can cause delays or even boot problems depending on your environment.

You must define DIB_CLOUD_INIT_DATASOURCES as a comma-separated list of valid data sources to limit the data sources that will be queried for metadata on first boot.

For instance, to enable only the Ec2 datasource:

export DIB_CLOUD_INIT_DATASOURCES="Ec2"

Or to enable multiple:

export DIB_CLOUD_INIT_DATASOURCES="Ec2, ConfigDrive, OpenStack"

Including this element without setting DIB_CLOUD_INIT_DATASOURCES will cause image builds to fail.