Dipak Dipak - 5 months ago 14
Bash Question

Parsing in Linux shell script

I am trying to parse the output below:

+--------------------------------------+-----------------+-----------+------+-----------+------+-------+-------------+-----------+
| ID | Name | Memory_MB | Disk | Ephemeral | Swap | VCPUs | RXTX_Factor | Is_Public |
+--------------------------------------+-----------------+-----------+------+-----------+------+-------+-------------+-----------+
| 1 | m1.tiny | 512 | 1 | 0 | | 1 | 1.0 | True |
| 2 | m1.small | 2048 | 20 | 0 | | 1 | 1.0 | True |
| 214b272c-e6a4-4bb5-96a4-c74c64984e5a | MC | 2048 | 100 | 0 | | 1 | 1.0 | True |
| 3 | m1.medium | 4096 | 40 | 0 | | 2 | 1.0 | True |
| 4 | m1.large | 8192 | 80 | 0 | | 4 | 1.0 | True |
| 5 | m1.xlarge | 16384 | 160 | 0 | | 8 | 1.0 | True |
| 71aa57d1-52e3-4499-abd2-23985949aeb4 | slmc | 4096 | 32 | 0 | | 2 | 1.0 | True |
| 7cf1d926-c904-47b8-af70-499196a1f65f | new test flavor | 1 | 1 | 0 | | 1 | 1.0 | True |
| 97b3dc38-f752-437b-881d-c3415c8a682c | slstore | 10240 | 32 | 0 | | 4 | 1.0 | True |
+--------------------------------------+-----------------+-----------+------+-----------+------+-------+-------------+-----------+


It is the list of flavours in open-stack. I am expecting output as below:

m1.tiny;m1.small;MC;m1.medium;m1.large;m1.xlarge;slmc;new test flavor;slstore;


What I tried:

I came up with below command for parsing:

nova flavor-list | grep '|' | awk 'NR>1 {print $4}' | tr '\n' ';'


but the issue is that the command returns output as follows:

m1.tiny;m1.small;MC;m1.medium;m1.large;m1.xlarge;slmc;new;slstore;


There is a problem with the space in
new test flavor
.

Answer

Below command will give expected output

nova flavor-list | grep '|' | awk -F "|" 'NR>1 {print $3}' | tr '\n' ';'

Above command will give output will white spaces i.e.

$ nova flavor-list | grep '|' | awk -F "|" 'NR>1  {print $3}' | tr '\n' ';'
 m1.tiny         ; m1.small        ; MC              ; m1.medium       ; m1.large        ; m1.xlarge       ; slmc            ; new test flavor ; slstore         ;

To get output without white spaces use below command

$nova flavor-list | grep '|' | awk -F "|" 'NR>1  {print $3}' | awk -F "\n" '{gsub(/^[ \t]+|[ \t]+$/, "", $1)}1' | tr '\n' ';' 
m1.tiny;m1.small;MC;m1.medium;m1.large;m1.xlarge;slmc;new test flavor;slstore;