JQ - Join nested arrays and filter - json

Question

I'm trying to use JQ to create the following paths:
/staging-data-0/cassandra/cassandra-client-port
/staging-data-0/cassandra/cassandra-gossip-port
from the following blob of JSON (I've stripped unnecessary bits out):
{
"DebugConfig": {
"ServerPort": 8300,
"Services": [
{
"Checks": [
{
"CheckID": "cassandra-client-port",
"Timeout": "1s"
},
{
"CheckID": "cassandra-gossip-port",
"Timeout": "1s"
}
],
"Name": "cassandra"
},
{
"Checks": [
{
"CheckID": "cockroachdb-tcp",
"Timeout": "1s"
}
],
"Name": "cockroachdb"
}
]
},
"Member": {
"Name": "staging-data-0"
},
"Meta": {
"consul-network-segment": ""
}
}
I'm struggling with the JQ manual to generate the paths, I can only pull out the last part so far with
jq '.DebugConfig.Services | map(select(.Name=="cassandra")) | map(.Checks[].CheckID)'
The final path should be /{.Member.Name}/{.DebugConfig.Services.Name}/{.DebugConfig.Services.Checks.CheckID}

Answer 1

Only cassandra
jq -r '{a:.Member.Name, b:.DebugConfig.Services[]} | select(.b.Name=="cassandra") | {a:.a, b:.b.Name, c:.b.Checks[].CheckID} | [.a, .b, .c] | join("/")'
staging-data-0/cassandra/cassandra-client-port
staging-data-0/cassandra/cassandra-gossip-port
Both
jq -r '{a:.Member.Name, b:.DebugConfig.Services[]} | {a:.a, b:.b.Name, c:.b.Checks[].CheckID} | [.a, .b, .c] | join("/")'
staging-data-0/cassandra/cassandra-client-port
staging-data-0/cassandra/cassandra-gossip-port
staging-data-0/cockroachdb/cockroachdb-tcp

Answer 2

With your input, the jq filter:
.DebugConfig.Services[] as $s
| "/\(.Member.Name)/\($s.Name)/\($s.Checks[].CheckID)"
produces:
"/staging-data-0/cassandra/cassandra-client-port"
"/staging-data-0/cassandra/cassandra-gossip-port"
"/staging-data-0/cockroachdb/cockroachdb-tcp"
Since you only want the "cassandra" strings, you just need to interject a "select" filter:
.DebugConfig.Services[] as $s
| "/\(.Member.Name)/\($s.Name)/" +
($s
| select(.Name == "cassandra")
| .Checks[].CheckID)
but it's worth noting how easy it is to process all the "Checks" items.