File-based configuration for local development

1config implements a hierarchical search when it looks for valid configurations. It searches in many different locations and a valid configuration. For more information please see the Configuration Providers for the details.

If you wish to use 1config for local development (without a connection to AWS DynamoDB) it is possible by creating entries in your 1config home directory (~/.1config/). You can override this directory by setting ONECONFIG_HOME in the environment.

You can create a files under ~/.1config/ (in your home) and put the configuration for one or more services in one or more environments with the following format: ~/.1config/<service-key>/<env>/<version>/<service-key>.<ext>

For example, these are all valid entries:

• ~/.1config/service1/dev/3.2.0/service1.edn
• ~/.1config/service1/dev/3.10.6/service1.txt
• ~/.1config/user-database/dev/1.0.0/user-database.properties
• ~/.1config/service1/staging/3.10.6/service1.json

The intended use of the configuration in ~/.1config/ is to facilitate development and allow the service to start with a local configuration which doesn't reside in your code.

The easiest way to set the configuration is by using 1cfg command line tool.

$ 1cfg list -b fs
|------------+-----+---------+------------+------+-----------|
| Config key | Env | Version | Change num | Type | Timestamp |
|------------+-----+---------+------------+------+-----------|
|------------+-----+---------+------------+------+-----------|
(*) Timestamp is in local time.

Now create one entry:

$ 1cfg -b fs -k service1 -e local -v 1.2.3 -t edn set '{:server {:port 8080}}'

Now we can see it with the list command:

$ 1cfg list -b fs
|------------+-------+---------+---------------+------+----------------------|
| Config key |  Env  | Version |   Change num  | Type |       Timestamp      |
|------------+-------+---------+---------------+------+----------------------|
| service1   | local | 1.2.3   | 1580063063132 | edn  | 2020-01-26  18:24:23 |
|------------+-------+---------+---------------+------+----------------------|
(*) Timestamp is in local time.

Now let's inspect the content of the 1config home:

$ find ~/.1config
~/.1config
~/.1config/user-profiles.edn
~/.1config/service1
~/.1config/service1/local
~/.1config/service1/local/1.2.3
~/.1config/service1/local/1.2.3/service1.edn

And if we check the content, no surprise, it's what we set:

$ cat ~/.1config/service1/local/1.2.3/service1.edn
{:server {:port 8080}}

NOTE: It is convention to use local environment name for local development but it is not a requirement the name of the environment can be anything.

NOTE: Be aware that if a config entry exists in the local filesystem (via -b fs) for a key/env which is also in DynamoDB, the local filesystem will supersede the DynamoDB backend, even if a better match exists in the dynamo backend. This is to allow local overrides of remote configurations.

NOTE: You can set the filesystem as your default local backend either using the environment variable ONECONFIG_DEFAULT_BACKEND (for example export ONECONFIG_DEFAULT_BACKEND=fs) or via the Java property 1config.default.backend (ex: -D1config.default.backend=fs).