consul-patch-json

A small tool used to patch JSON values in consul.

Usage:

$ consul-patch-json apps/foo/config version='"1.0.0"'

Installation

$ cargo install consul-patch-json

Consul Configuration

The following environment variables are used to configure consul interaction:

• CONSUL_HTTP_ADDR
• CONSUL_CACERT
• CONSUL_CAPATH
• CONSUL_CLIENT_CERT
• CONSUL_CLIENT_KEY
• CONSUL_HTTP_TOKEN
• CONSUL_HTTP_SSL_VERIFY

Examples

Adding attributes

$ consul kv put apps/foo/config '{"version": "1.0.0"}'
$ consul-patch-json apps/foo/config description='"My app"'
$ consul kv get apps/foo/config
{"description":"My app","version":"1.0.0"}

Replacing attributes

$ consul kv put apps/foo/config '{"version": "1.0.0"}'
$ consul-patch-json apps/foo/config version='"1.0.1"'
$ consul kv get apps/foo/config
{"version":"1.0.1"}

Complex attributes

$ consul kv put apps/foo/config '{"version": "1.0.0"}'
$ consul-patch-json apps/foo/config features='["metrics"]'
$ consul kv get apps/foo/config
{"features":["metrics"],"version":"1.0.0"}

Reading standard input for single attributes

$ consul kv put apps/foo/config '{"version": "1.0.0"}'
$ echo '["coffee"]' | consul-patch-json apps/foo/config features=--
$ consul kv get apps/foo/config
{"features":["coffee"],"version":"1.0.0"}

JSON Merge Patch (RFC 7396)

$ consul kv put apps/foo/config '{"version": "1.0.0"}'
$ jo features=$(jo -a coffee metrics) | consul-patch-json apps/foo/config --
$ consul kv get apps/foo/config
{"features":["coffee","metrics"],"version":"1.0.0"}

See also: https://datatracker.ietf.org/doc/html/rfc7396

JSON Patch (RFC 6902)

$ consul kv put apps/foo/config '{"version": "1.0.0","features":["coffee"]}'
$ cat > patch.json <<EOF
[
    {"op": "test", "path": "/version", "value": "1.0.0"},
    {"op": "add","path": "/features/0", "value": "metrics"}
]
EOF
$ cat patch.json | consul-patch-json apps/foo/config --json-patch --
$ consul kv get apps/foo/config
{"features":["coffee","metrics"],"version":"1.0.0"}

See also: https://datatracker.ietf.org/doc/html/rfc6902

TODO

• Support transactions