How do I know when to use which hyperledger fabric docker container env variables

Question

I played around with Hyperledger Fabric lately and I'm not able to find a good and exhaustive description of ALL environment variables one can set on the hyperledger fabric docker containers (fabric-orderer, fabric-peer, fabric-ca, fabric-tools, fabric-kafka, ...)

Is there such a documentation? I only find so little about the possible variables and what their different values would do and when one would choose which value; even on the official documentation.

Can anyone provide such a list with explanation? Or can we collect information to create such a list?

Ideally, I would like to have something like the following:

---

fabric-orderer

ORDERER_GENERAL_GENESISMETHOD  

values: file, provisional (default)

file is used when you want provide the genesis block as file to the container (see ORDERER_GENERAL_GENESISFILE)

provisional is used when ...

ORDERER_GENERAL_GENESISFILE

value(s): path to genesis file path

---

fabric-peer

some env var

... explanation ...

---

Here's also a sample list of some env variables I've seen other people using and don't why, what it means or if it even works:

• ORDERER_GENERAL_LEDGERTYPE
• ORDERER_GENERAL_BATCHTIMEOUT
• ORDERER_GENERAL_MAXWINDOWSIZE
• CONFIGTX_ORDERER_KAFKA_BROKERS
• ORDERER_GENERAL_LISTENADDRESS
• ORDERER_GENERAL_PORT
• ORDERER_GENERAL_HOST
• ...

I hope asking this question here is ok (it's my first).
Thanks a lot for your help!

Answer 1

This is a great question, and would indeed make a good addition to the docs. It is not currently explicitly documented, but I can explain at least how you can determine what the variables are.

We use viper for managing configuration. We ship a sample configuration with the distribution of the docker images and binaries. As you can see, there are three configuration yaml files: configtx.yaml, core.yaml and orderer.yaml. For each configuration parameter in the yaml file, you can derive an environment variable that can be used to override the value in the config file used at startup. The environment variable name is derived from the filename (e.g. CORE for core.yaml), and underscore-separated capitalization of the nested properties in the config, (e.g. CORE_LOGGING_LEVEL).

The sample apps provided contain docker-compose yaml configurations that leverage most of the properties you might consider leveraging for your own purposes.

Meanwhile, I have created a JIRA to track this and invite contributions to help us flesh out an addition to our documentation that provides a useful reference.