Hi Jim,

Until the bosh contributors get you an official doc, here are some pointers
I collected while studying the development of an external CPI [1]


- Stdin/stdout API wiki
<https://github.com/cloudfoundry/bosh/wiki/BOSH-CPI-API-v1-%28WIP%29>
- Sequenting of calls
<https://groups.google.com/a/cloudfoundry.org/d/msg/bosh-dev/QbZjCBJwNPE/dazJAUcjIEIJ>
- *"One way to find out order of all those things is to run bosh-lite
and look at the logs. All cpi methods act on some resources that
have cloud
ids. e.g. attach_disk for example takes vm_cid and disk_cid which means
that create_vm and create_disk would be called at some point before this.
Important thing to note is that bosh may call any of those methods in a
different order depending on the situation as long as bosh is able to
provide needed arguments to the methods."*
- *Another way is to look at the debug traces from the bosh-init
logging <https://bosh.io/docs/using-bosh-init.html#logging>*
- diagrams:
- deploy flow
<https://github.com/cloudfoundry/bosh-init/blob/master/docs/architecture.md#deploy-command-flow>
- delete flow
<https://github.com/cloudfoundry/bosh-init/blob/master/docs/architecture.md#delete-command-flow>


BTW, which Iaas are you looking at developping a CPI for ?

Hope this helps,

Guillaume.

[1]
https://github.com/cloudfoundry-community/bosh-cloudstack-cpi/issues/23#issuecomment-109260841