Looping thru multiple regex matches with bash [duplicate] - json

Question

Just started out with Bash scripting and stumbled upon jq to work with JSON.
I need to transform a JSON string like below to a table for output in the terminal.
[{
"name": "George",
"id": 12,
"email": "george#domain.example"
}, {
"name": "Jack",
"id": 18,
"email": "jack#domain.example"
}, {
"name": "Joe",
"id": 19,
"email": "joe#domain.example"
}]
What I want to display in the terminal:
ID Name
=================
12 George
18 Jack
19 Joe
Notice how I don't want to display the email property for each row, so the jq command should involve some filtering. The following gives me a plain list of names and id's:
list=$(echo "$data" | jq -r '.[] | .name, .id')
printf "$list"
The problem with that is, I cannot display it like a table. I know jq has some formatting options, but not nearly as good as the options I have when using printf. I think I want to get these values in an array which I can then loop through myself to do the formatting...? The things I tried give me varying results, but never what I really want.
Can someone point me in the right direction?

Answer 1

Using the #tsv filter has much to recommend it, mainly because it handles numerous "edge cases" in a standard way:
.[] | [.id, .name] | #tsv
Adding the headers can be done like so:
jq -r '["ID","NAME"], ["--","------"], (.[] | [.id, .name]) | #tsv'
The result:
ID NAME
-- ------
12 George
18 Jack
19 Joe
As pointed out by #Tobia, you might want to format the table for viewing by using column to post-process the result produced by jq. If you are using a bash-like shell then column -ts $'\t' should be quite portable.
length*"-"
To automate the production of the line of dashes:
jq -r '(["ID","NAME"] | (., map(length*"-"))), (.[] | [.id, .name]) | #tsv'

Answer 2

Why not something like:
echo '[{
"name": "George",
"id": 12,
"email": "george#domain.example"
}, {
"name": "Jack",
"id": 18,
"email": "jack#domain.example"
}, {
"name": "Joe",
"id": 19,
"email": "joe#domain.example"
}]' | jq -r '.[] | "\(.id)\t\(.name)"'
Output
12 George
18 Jack
19 Joe
Edit 1 : For fine grained formatting use tools like awk
echo '[{
"name": "George",
"id": 12,
"email": "george#domain.example"
}, {
"name": "Jack",
"id": 18,
"email": "jack#domain.example"
}, {
"name": "Joe",
"id": 19,
"email": "joe#domain.example"
}]' | jq -r '.[] | [.id, .name] | #csv' | awk -v FS="," 'BEGIN{print "ID\tName";print "============"}{printf "%s\t%s%s",$1,$2,ORS}'
ID Name
============
12 "George"
18 "Jack"
19 "Joe"
Edit 2 : In reply to
There's no way I can get a variable containing an array straight
from jq?
Why not?
A bit involved example( in fact modified from yours ) where email is changed to an array demonstrates this
echo '[{
"name": "George",
"id": 20,
"email": [ "george#domain1.example" , "george#domain2.example" ]
}, {
"name": "Jack",
"id": 18,
"email": [ "jack#domain3.example" , "jack#domain5.example" ]
}, {
"name": "Joe",
"id": 19,
"email": [ "joe#domain.example" ]
}]' | jq -r '.[] | .email'
Output
[
"george#domain1.example",
"george#domain2.example"
]
[
"jack#domain3.example",
"jack#domain5.example"
]
[
"joe#domain.example"
]

Answer 3

Defining headers by hand is suboptimal! Omitting headers is also suboptimal.
TL;DR
data
[{ "name": "George", "id": 12, "email": "george#domain.example" },
{ "name": "Jack", "id": 18, "email": "jack#domain.example" },
{ "name": "Joe", "id": 19, "email": "joe#domain.example" }]
script
[.[]| with_entries( .key |= ascii_downcase ) ]
| (.[0] |keys_unsorted | #tsv)
, (.[] |map(.) |#tsv)
how to run
$ < data jq -rf script | column -t
name id email
George 12 george#domain.example
Jack 18 jack#domain.example
Joe 19 joe#domain.example
I found this question while summarizng some data from amazon web services. The problem I was working on, in case you want another example:
$ aws ec2 describe-spot-instance-requests | tee /tmp/ins |
jq --raw-output '
# extract instances as a flat list.
[.SpotInstanceRequests | .[]
# remove unwanted data
| {
State,
statusCode: .Status.Code,
type: .LaunchSpecification.InstanceType,
blockPrice: .ActualBlockHourlyPrice,
created: .CreateTime,
SpotInstanceRequestId}
]
# lowercase keys
# (for predictable sorting, optional)
| [.[]| with_entries( .key |= ascii_downcase ) ]
| (.[0] |keys_unsorted | #tsv) # print headers
, (.[]|.|map(.) |#tsv) # print table
' | column -t
Output:
state statuscode type blockprice created spotinstancerequestid
closed instance-terminated-by-user t3.nano 0.002000 2019-02-24T15:21:36.000Z sir-r5bh7skq
cancelled bad-parameters t3.nano 0.002000 2019-02-24T14:51:47.000Z sir-1k9s5h3m
closed instance-terminated-by-user t3.nano 0.002000 2019-02-24T14:55:26.000Z sir-43x16b6n
cancelled bad-parameters t3.nano 0.002000 2019-02-24T14:29:23.000Z sir-2jsh5brn
active fulfilled t3.nano 0.002000 2019-02-24T15:37:26.000Z sir-z1e9591m
cancelled bad-parameters t3.nano 0.002000 2019-02-24T14:33:42.000Z sir-n7c15y5p
Input:
$ cat /tmp/ins
{
"SpotInstanceRequests": [
{
"Status": {
"Message": "2019-02-24T15:29:38+0000 : 2019-02-24T15:29:38+0000 : Spot Instance terminated due to user-initiated termination.",
"Code": "instance-terminated-by-user",
"UpdateTime": "2019-02-24T15:31:03.000Z"
},
"ActualBlockHourlyPrice": "0.002000",
"ValidUntil": "2019-03-03T15:21:36.000Z",
"InstanceInterruptionBehavior": "terminate",
"Tags": [],
"InstanceId": "i-0414083bef5e91d94",
"BlockDurationMinutes": 60,
"SpotInstanceRequestId": "sir-r5bh7skq",
"State": "closed",
"ProductDescription": "Linux/UNIX",
"LaunchedAvailabilityZone": "eu-north-1a",
"LaunchSpecification": {
"Placement": {
"Tenancy": "default",
"AvailabilityZone": "eu-north-1a"
},
"ImageId": "ami-6d27a913",
"BlockDeviceMappings": [
{
"DeviceName": "/dev/sda1",
"VirtualName": "root",
"NoDevice": "",
"Ebs": {
"Encrypted": false,
"DeleteOnTermination": true,
"VolumeType": "gp2",
"VolumeSize": 8
}
}
],
"EbsOptimized": false,
"SecurityGroups": [
{
"GroupName": "default"
}
],
"Monitoring": {
"Enabled": false
},
"InstanceType": "t3.nano",
"AddressingType": "public",
"NetworkInterfaces": [
{
"DeviceIndex": 0,
"Description": "eth-zero",
"NetworkInterfaceId": "",
"DeleteOnTermination": true,
"SubnetId": "subnet-420ffc2b",
"AssociatePublicIpAddress": true
}
]
},
"Type": "one-time",
"CreateTime": "2019-02-24T15:21:36.000Z",
"SpotPrice": "0.008000"
},
{
"Status": {
"Message": "Your Spot request failed due to bad parameters.",
"Code": "bad-parameters",
"UpdateTime": "2019-02-24T14:51:48.000Z"
},
"ActualBlockHourlyPrice": "0.002000",
"ValidUntil": "2019-03-03T14:51:47.000Z",
"InstanceInterruptionBehavior": "terminate",
"Tags": [],
"Fault": {
"Message": "Invalid device name /dev/sda",
"Code": "InvalidBlockDeviceMapping"
},
"BlockDurationMinutes": 60,
"SpotInstanceRequestId": "sir-1k9s5h3m",
"State": "cancelled",
"ProductDescription": "Linux/UNIX",
"LaunchedAvailabilityZone": "eu-north-1a",
"LaunchSpecification": {
"Placement": {
"Tenancy": "default",
"AvailabilityZone": "eu-north-1a"
},
"ImageId": "ami-6d27a913",
"BlockDeviceMappings": [
{
"DeviceName": "/dev/sda",
"VirtualName": "root",
"NoDevice": "",
"Ebs": {
"Encrypted": false,
"DeleteOnTermination": true,
"VolumeType": "gp2",
"VolumeSize": 8
}
}
],
"EbsOptimized": false,
"SecurityGroups": [
{
"GroupName": "default"
}
],
"Monitoring": {
"Enabled": false
},
"InstanceType": "t3.nano",
"AddressingType": "public",
"NetworkInterfaces": [
{
"DeviceIndex": 0,
"Description": "eth-zero",
"NetworkInterfaceId": "",
"DeleteOnTermination": true,
"SubnetId": "subnet-420ffc2b",
"AssociatePublicIpAddress": true
}
]
},
"Type": "one-time",
"CreateTime": "2019-02-24T14:51:47.000Z",
"SpotPrice": "0.011600"
},
{
"Status": {
"Message": "2019-02-24T15:02:17+0000 : 2019-02-24T15:02:17+0000 : Spot Instance terminated due to user-initiated termination.",
"Code": "instance-terminated-by-user",
"UpdateTime": "2019-02-24T15:03:34.000Z"
},
"ActualBlockHourlyPrice": "0.002000",
"ValidUntil": "2019-03-03T14:55:26.000Z",
"InstanceInterruptionBehavior": "terminate",
"Tags": [],
"InstanceId": "i-010442ac3cc85ec08",
"BlockDurationMinutes": 60,
"SpotInstanceRequestId": "sir-43x16b6n",
"State": "closed",
"ProductDescription": "Linux/UNIX",
"LaunchedAvailabilityZone": "eu-north-1a",
"LaunchSpecification": {
"Placement": {
"Tenancy": "default",
"AvailabilityZone": "eu-north-1a"
},
"ImageId": "ami-6d27a913",
"BlockDeviceMappings": [
{
"DeviceName": "/dev/sda1",
"VirtualName": "root",
"NoDevice": "",
"Ebs": {
"Encrypted": false,
"DeleteOnTermination": true,
"VolumeType": "gp2",
"VolumeSize": 8
}
}
],
"EbsOptimized": false,
"SecurityGroups": [
{
"GroupName": "default"
}
],
"Monitoring": {
"Enabled": false
},
"InstanceType": "t3.nano",
"AddressingType": "public",
"NetworkInterfaces": [
{
"DeviceIndex": 0,
"Description": "eth-zero",
"NetworkInterfaceId": "",
"DeleteOnTermination": true,
"SubnetId": "subnet-420ffc2b",
"AssociatePublicIpAddress": true
}
]
},
"Type": "one-time",
"CreateTime": "2019-02-24T14:55:26.000Z",
"SpotPrice": "0.011600"
},
{
"Status": {
"Message": "Your Spot request failed due to bad parameters.",
"Code": "bad-parameters",
"UpdateTime": "2019-02-24T14:29:24.000Z"
},
"ActualBlockHourlyPrice": "0.002000",
"ValidUntil": "2019-03-03T14:29:23.000Z",
"InstanceInterruptionBehavior": "terminate",
"Tags": [],
"Fault": {
"Message": "Addressing type must be 'public'",
"Code": "InvalidParameterCombination"
},
"BlockDurationMinutes": 60,
"SpotInstanceRequestId": "sir-2jsh5brn",
"State": "cancelled",
"ProductDescription": "Linux/UNIX",
"LaunchedAvailabilityZone": "eu-north-1a",
"LaunchSpecification": {
"Placement": {
"Tenancy": "default",
"AvailabilityZone": "eu-north-1a"
},
"ImageId": "ami-6d27a913",
"BlockDeviceMappings": [
{
"DeviceName": "/dev/sda",
"VirtualName": "root",
"NoDevice": "",
"Ebs": {
"Encrypted": false,
"DeleteOnTermination": true,
"VolumeType": "gp2",
"VolumeSize": 8
}
}
],
"EbsOptimized": false,
"SecurityGroups": [
{
"GroupName": "default"
}
],
"Monitoring": {
"Enabled": false
},
"InstanceType": "t3.nano",
"AddressingType": "",
"NetworkInterfaces": [
{
"DeviceIndex": 0,
"Description": "eth-zero",
"NetworkInterfaceId": "",
"DeleteOnTermination": true,
"SubnetId": "subnet-420ffc2b",
"AssociatePublicIpAddress": true
}
]
},
"Type": "one-time",
"CreateTime": "2019-02-24T14:29:23.000Z",
"SpotPrice": "0.011600"
},
{
"Status": {
"Message": "Your spot request is fulfilled.",
"Code": "fulfilled",
"UpdateTime": "2019-02-24T15:37:28.000Z"
},
"ActualBlockHourlyPrice": "0.002000",
"ValidUntil": "2019-03-03T15:37:26.000Z",
"InstanceInterruptionBehavior": "terminate",
"Tags": [],
"InstanceId": "i-0a29e9de6d59d433f",
"BlockDurationMinutes": 60,
"SpotInstanceRequestId": "sir-z1e9591m",
"State": "active",
"ProductDescription": "Linux/UNIX",
"LaunchedAvailabilityZone": "eu-north-1a",
"LaunchSpecification": {
"Placement": {
"Tenancy": "default",
"AvailabilityZone": "eu-north-1a"
},
"ImageId": "ami-6d27a913",
"BlockDeviceMappings": [
{
"DeviceName": "/dev/sda1",
"VirtualName": "root",
"NoDevice": "",
"Ebs": {
"Encrypted": false,
"DeleteOnTermination": true,
"VolumeType": "gp2",
"VolumeSize": 8
}
}
],
"EbsOptimized": false,
"SecurityGroups": [
{
"GroupName": "default"
}
],
"Monitoring": {
"Enabled": false
},
"InstanceType": "t3.nano",
"AddressingType": "public",
"NetworkInterfaces": [
{
"DeviceIndex": 0,
"Description": "eth-zero",
"NetworkInterfaceId": "",
"DeleteOnTermination": true,
"SubnetId": "subnet-420ffc2b",
"AssociatePublicIpAddress": true
}
]
},
"Type": "one-time",
"CreateTime": "2019-02-24T15:37:26.000Z",
"SpotPrice": "0.008000"
},
{
"Status": {
"Message": "Your Spot request failed due to bad parameters.",
"Code": "bad-parameters",
"UpdateTime": "2019-02-24T14:33:43.000Z"
},
"ActualBlockHourlyPrice": "0.002000",
"ValidUntil": "2019-03-03T14:33:42.000Z",
"InstanceInterruptionBehavior": "terminate",
"Tags": [],
"Fault": {
"Message": "Invalid device name /dev/sda",
"Code": "InvalidBlockDeviceMapping"
},
"BlockDurationMinutes": 60,
"SpotInstanceRequestId": "sir-n7c15y5p",
"State": "cancelled",
"ProductDescription": "Linux/UNIX",
"LaunchedAvailabilityZone": "eu-north-1a",
"LaunchSpecification": {
"Placement": {
"Tenancy": "default",
"AvailabilityZone": "eu-north-1a"
},
"ImageId": "ami-6d27a913",
"BlockDeviceMappings": [
{
"DeviceName": "/dev/sda",
"VirtualName": "root",
"NoDevice": "",
"Ebs": {
"Encrypted": false,
"DeleteOnTermination": true,
"VolumeType": "gp2",
"VolumeSize": 8
}
}
],
"EbsOptimized": false,
"SecurityGroups": [
{
"GroupName": "default"
}
],
"Monitoring": {
"Enabled": false
},
"InstanceType": "t3.nano",
"AddressingType": "public",
"NetworkInterfaces": [
{
"DeviceIndex": 0,
"Description": "eth-zero",
"NetworkInterfaceId": "",
"DeleteOnTermination": true,
"SubnetId": "subnet-420ffc2b",
"AssociatePublicIpAddress": true
}
]
},
"Type": "one-time",
"CreateTime": "2019-02-24T14:33:42.000Z",
"SpotPrice": "0.011600"
}
]
}

Answer 4

The problem with the answers above is they only work if the fields are all about the same width.
To avoid this issue, the Linux column command could be used:
// input.json
[
{
"name": "George",
"id": "a very very long field",
"email": "george#domain.example"
},
{
"name": "Jack",
"id": 18,
"email": "jack#domain.example"
},
{
"name": "Joe",
"id": 19,
"email": "joe#domain.example"
}
]
Then:
▶ jq -r '.[] | [.id, .name] | #tsv' input.json | column -ts $'\t'
a very very long field George
18 Jack
19 Joe

Answer 5

I made a mix with all responses to get all this behaviours
create header table
handle long fields
create a function to reuse
function bash
function jsonArrayToTable(){
jq -r '(.[0] | ([keys[] | .] |(., map(length*"-")))), (.[] | ([keys[] as $k | .[$k]])) | #tsv' | column -t -s $'\t'
}
Sample use
echo '[{"key1":"V1.1", "key2":"V2.1"}, {"keyA":"V1.2", "key2":"V2.2"}]' | jsonArrayToTable
output
key1 key2
---- ----
V1.1 V2.1
V2.2 V1.2

Answer 6

If you want to generate an HTML table instead of a table for terminal output:
echo '[{
"name": "George",
"id": 12,
"email": "george#domain.example"
}, {
"name": "Jack",
"id": 18,
"email": "jack#domain.example"
}, {
"name": "Joe",
"id": 19,
"email": "joe#domain.example"
}]' | jq -r 'map("<tr><td>" + .name + "</td><td>" + (.id | tostring) + "</td></tr>") | ["<table>"] + . + ["</table>"] | .[]'
Output:
<table>
<tr><td>George</td><td>12</td></tr>
<tr><td>Jack</td><td>18</td></tr>
<tr><td>Joe</td><td>19</td></tr>
</table>

Answer 7

If the values don't contain spaces, this might be helpful:
read -r -a data <<<'name1 value1 name2 value2'
echo "name value"
echo "=========="
for ((i=0; i<${#data[#]}; i+=2)); do
echo ${data[$i]} ${data[$((i+1))]}
done
Output
name value
==========
name1 value1
name2 value2

Answer 8

More simple implement:
jq -r '(.[0]|keys_unsorted|(.,map(length*"-"))),.[]|map(.)|#tsv'|column -ts $'\t'
you can add the following jq function into ~/.jq:
def pretty_table:
(.[0]|keys_unsorted|(.,map(length*"-"))),.[]|map(.)|#tsv
;
and then run:
cat apps.json | jq -r pretty_table | column -ts $'\t'