Building JSON command with bash script


Login or Register for Dates, Times and to Reply

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting Building JSON command with bash script
# 43  
I'd keep it simply with a case statement like in post #41

Code:
send_multiple_payment(){
   eval_send_amount
   mk_json_object_one_val "$btc_amount_dec" "${addr_arr[@]}"
   mk_json_lst_one_val "${addr_arr[@]}"
   echo "\$used_net is: $used_net"
   case "$used_net" in
       testnet) echo "bitcoin-cli -testnet sendmany \"\" {$pairs} 6 Payments [$items] true 6 CONSERVATIVE" ;;
             *) echo "bitcoin-cli sendmany \"\" {$pairs} 6 Payments [$items] true 6 CONSERVATIVE"
   esac
   #echo "TxID: $1"
 }

# 44  
Quote:
Originally Posted by Chubler_XL
I'd keep it simply with a case statement like in post #41

Code:
send_multiple_payment(){
   eval_send_amount
   mk_json_object_one_val "$btc_amount_dec" "${addr_arr[@]}"
   mk_json_lst_one_val "${addr_arr[@]}"
   echo "\$used_net is: $used_net"
   case "$used_net" in
       testnet) echo "bitcoin-cli -testnet sendmany \"\" {$pairs} 6 Payments [$items] true 6 CONSERVATIVE" ;;
             *) echo "bitcoin-cli sendmany \"\" {$pairs} 6 Payments [$items] true 6 CONSERVATIVE"
   esac
   #echo "TxID: $1"
 }

Yes, I understand your suggestion but I would like to know what is wrong with the 'test' I'm using there! It's so simple that I can't understand why it's not working!

Edited;
In the meantime I did another test with my code. I used 'if...then...fi' and it works... :s

Code:
send_multiple_payment(){
   eval_send_amount
   mk_json_object_one_val "$btc_amount_dec" "${addr_arr[@]}"
   mk_json_lst_one_val "${addr_arr[@]}"
   echo "\$used_net is: $used_net"
   if [ "$used_net" == "testnet" ]; then
     echo "bitcoin-cli -testnet sendmany "" {$pairs} 6 Payments [$items] true 6 CONSERVATIVE"
   else
     echo "bitcoin-cli sendmany "" {$pairs} 6 Payments [$items] true 6 CONSERVATIVE"
   fi
 #echo "TxID: $1"
 }

Code:
./auto_trbtc.sh -m -a addr_lst.dat
2 addresses sucessefuly loaded.

0.00256372
$used_net is: mainnet
bitcoin-cli sendmany  {"n1yswZYByRv3okGDHs1oDaevq8gsDaYZzC":"0.00256372","2NFafKRugHFdYEib7xVfkT6bvtkUKK8oShZ":"0.00256372"} 6 Payments ["n1yswZYByRv3okGDHs1oDaevq8gsDaYZzC","2NFafKRugHFdYEib7xVfkT6bvtkUKK8oShZ"] true 6 CONSERVATIVE

Code:
./auto_trbtc.sh -t -a addr_lst.dat
2 addresses sucessefuly loaded.

0.07931717
$used_net is: testnet
bitcoin-cli -testnet sendmany  {"n1yswZYByRv3okGDHs1oDaevq8gsDaYZzC":"0.07931717","2NFafKRugHFdYEib7xVfkT6bvtkUKK8oShZ":"0.07931717"} 6 Payments ["n1yswZYByRv3okGDHs1oDaevq8gsDaYZzC","2NFafKRugHFdYEib7xVfkT6bvtkUKK8oShZ"] true 6 CONSERVATIVE


Last edited by psysc0rpi0n; 10-01-2019 at 07:54 PM..
# 45  
Hello psy,

as you saw in the last post from Chubler and me, that we have different views on what is the preferred choice of coding. I hope this causes not too much confusion for you.

Global And Local Variables

I just checked your code at github and want to mention, that you are using global variables a lot which one should better avoid. Use local variables instead. A global variable is a variable that is accessible and changeable everywhere in the program. There's a danger if a global variable is changed/used where it is unexpected. One may use even the same variable name in different places for different purposes. It most likely will break the program. A local variable is valid only inside of a function in which it is defined.

Example:

Code:
# this is global
name="tony stark"

give_name() {

     # this is local
     local name="bruce banner"     # <--- this is the local variable name
                                   #      only valid in this function

     echo "$name"                  # <--- echo produces output of local variable name
}

give_name                          # <--- outputs what function give_name does ("bruce banner")

echo "hello $name"                 # <--- name is the global assigned name "tony stark"

name="$(give_name)"                # <--- assigns output of function 
                                   #      give_name()(="bruce banner") to global variable "name"

echo "hello $name"                 # <--- output newly assigned value of global variable

Output:

Code:
bruce banner
hello tony stark
hello bruce banner

Function Arguments And Return Values

A recommended way is to put what you need as arguments into your function and return back what you want from the function. Returning back in bash means mostly to print it(echo, printf, ...). (yes, return also exists, but I try to make it easy).

A simple example:

Code:
add() { 
   echo "$(( $1 + $2 ))"
}

sum="$( add "5" "4" )"

The function add takes 2 arguments, adds them and prints them. The output is received from the function and put into the (global) variable sum.

See also: Local Variables

P. S.: To avoid global variables is a good coding practice for starting. If one internalized it, one may break the habit occasionally.

Last edited by stomp; 10-01-2019 at 08:40 PM..
This User Gave Thanks to stomp For This Post:
# 46  
Quote:
Originally Posted by psysc0rpi0n
Yes, I understand your suggestion but I would like to know what is wrong with the 'test' I'm using there! It's so simple that I can't understand why it's not working!
&& and || control operators examine the exit status last command executed in the list.

If the last command has a zero exit status then a command following && will run:
Code:
$ [ 1 -eq 0 ]
$ echo $?
1
$ [ 1 -eq 1 ] && echo yes
yes

if the exit status is non-zero then the command following || will run:
Code:
$ [ 1 -eq 0 ]
$ echo $?
1
$ [ 1 -eq 0 ] || echo no
no

This is fairly straight forward so far. However when you string 2 control operators together like this:

Code:
$ [ 1 -eq 0 ] || echo no && echo yes

The exist status of the test is non-zero so echo no is executed. Following this the exit status of echo no is examined and found to be zero so echo yes is then executed.

For this reason I avoid stringing && and || control operators together in a single command line.

I don't mind stringing multiple && control operators together, this has the effect of continuing executing of each command as long as it's predecessor succeeds:
Code:
command1 && command2 && command3 && command4

--- Post updated at 01:07 PM ---

As a side note I'd like to discuss the code presented by Stomp earlier:

Code:
[ "$used_net" == "testnet" ] && btcopt="-testnet" || btcopt=

This works as intended because the command in the middle will always succeed (return a zero exit status) so the end command is not executed.

However, I feel this is a small time bomb waiting for someone to come along later, and because it isn't directly obvious that the execution of the 3rd command is dependent on the exit status of the 2nd (not the original test as many could assume) they change the 2nd command.
Example:
Code:
$ [ 1 -eq 1 ] && grep NotFound /dev/null || echo no
no

The above grep is just an illustration, any other command that has the potential to return a non-zero value would break the original intent.
This User Gave Thanks to Chubler_XL For This Post:
# 47  
@stomp

thanks for the suggestions and explanations.

There is no confusion about different ways of coding. I absolutely understand both approaches.

I'm also aware of global and local variables. I might have gave the wrong idea about me. I have some basic background in programming, mostly C language. So I have minimal and basic understanding about a few programming concepts, but of course I'm no expert. I don't do this for living and never did.

I started using global variables because when I started this script I never thought it would turn this difficult or so big. This was supposed to be a script to run a single command but then I got excited and tried to add some more features and things got more complicated very quickly. So, that's why I started with global variables. one or two variables were supposed to be enough.

I'm perfectly comfortable with generic idea of 'if' and 'case' (switch case in C). I'm not as comfortable with loops as with conditional statements because they can be quite different from C. It's way closer to python but my python knowledge is also very limited.
Passing arguments into functions and calling functions themselves is also a bit different. Anyways, code is almost as I want it to be!...

I'm just bothered with something yet about 'test'.
This function I have in another version of my script, works as I was expecting. I mean, it never runs both commands like the function we have been talking lately about.
Is there any explanation for this:
Code:
# ------ Check loaded wallet balance ------ #
 check_balance(){
   echo "used_net: $used_net"
   echo Checking Full Node data...
   echo Current wallet has:
   [ "$used_net" == "testnet" ] && bitcoin-cli -testnet getbalance\
                                || bitcoin-cli getbalance
 }

This is another example of another function that is working correctly, or at least gives me the expected results, using '[]'.

Code:
eval_send_amount(){
   [ "$used_net" == "testnet" ] && btc_dec=$(bitcoin-cli -testnet getbalance)\
                                || btc_dec=$(bitcoin-cli getbalance)
   btc_sats=$(echo "$btc_dec * 1*10^8" | bc)
   btc_sats_amount=$(echo "$btc_sats / $num_addr" | bc)
   btc_amount_dec=$(printf "%.8f" $(echo "scale=8; $btc_sats_amount / (1*10^8)" | bc -l))
   echo "$btc_amount_dec"
 }

@Chubler_XL

You examples are next to be tried out in my terminal. Thanks for the simple and clear bits about my questions.

Thanks
Psy


Edited;
I'll update github files with latest versions of the scripts (versions of) that I'm actually working on.
They are basically the same but one will be to run with no human interference (with cron if possible) and the other one provides menus to run specific tasks by hand.
I'll paste here the link to github when I update the repository!


Eited 2;
I forgot one question.
The function we have been talking lately, the one called "send_multiple_payment" (or "sendmany" or "send_many", I think I've been changing its name from version of script to version of script) will run a command "bitcoin-cli sendmany blablabla........" and this command will return a value which is the transaction ID an it prints it out directly to stdout. I want to be able to show it by myself so I need to omit the output given by bitcoin-cli and fetch it somehow manually and print it myself using my code. I can I do this? I think I can redirect the command output with that thing "2>&1" or whatever it is but then how do I get it to be able to print it myself?

Last edited by psysc0rpi0n; 10-02-2019 at 06:45 PM..
# 48  
Anyone still around?

I'm trying to cut off global variables in my script but looks like there aren't that many variables I can change scope.
# 49  
Hello...

I've started to try something new for my script.
I'm trying to iterate over a JSON object, search for a specific value in all keys present in that object and finally, add those values.
Knowing that a specific key value can be accessed by

Code:
echo "$json_obj" | jq '.[0] .key'

I tried to use a variable to iterate through all keys and print their values

Code:
json_obj=(bitcoin-cli listunspent)
for i in "${#json_obj}";
do
echo "$json_obj" | jq '.[$i] .address'

But I get the following error which I can't fix.

Quote:
jq: error: i/0 is not defined at <top-level>, line 1:
.[$i] .address
jq: 1 compile error
I think this means that 'jq' cannot "expand" the $i variable so it returns that error, but I have no idea how to fix this!

Any help?

Edited;
I even tried this, but couldn't make it work either
Bash for Loop Over JSON Array Using jq

Last edited by psysc0rpi0n; 10-14-2019 at 08:09 PM..
Login or Register for Dates, Times and to Reply

Previous Thread | Next Thread
Thread Tools Search this Thread
Search this Thread:
Advanced Search

Test Your Knowledge in Computers #641
Difficulty: Medium
NeXTSTEP had a Unix operating system based on the Minix kernel, plus source code from System V.
True or False?

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

How to convert any shell command output to JSON format?

Hi All, I am new to shell scripting, Need your help in creating a shell script which converts any unix command output to JSON format output. example: sample df -h command ouput : Filesystem size used avail capacity Mounted /dev/dsk/c1t0d0s0 8.1G 4.0G 4.0G 50% /... (11 Replies)
Discussion started by: balu1234
11 Replies

2. Shell Programming and Scripting

Fun with terminal plotting JSON data at the command line

One of the great thing about unix is the ability to pipe multiple programs together to manipulate data. Plain, unstructured text is the most common type of data that is passed between programs, but these days JSON is becoming more popular. I thought it would be fun to pipe together some command... (1 Reply)
Discussion started by: kbrazil
1 Replies

3. Shell Programming and Scripting

JSON structure to table form in awk, bash

Hello guys, I want to parse a JSON file in order to get the data in a table form. My JSON file is like this: { "document":{ "page": }, { "column": } ] }, { ... (6 Replies)
Discussion started by: Gescad
6 Replies

4. UNIX for Beginners Questions & Answers

Json field grap via shell script/awk

i have a json data that looks like this: { "ip": "16.66.35.10", "hostname": "No Hostname", "city": "Stepney", "region": "England", "country": "GB", "loc": "51.57,-0.0333", "org": "AS6871 British Telecommunications PLC", "postal": "E1" } im looking for a way to assign... (9 Replies)
Discussion started by: SkySmart
9 Replies

5. Shell Programming and Scripting

Parsing and Editing a json file with bash script

I am trying to automate editing of a json file using bash script. The file I initially receive is { "appMap": { "URL1": { "name": "a" }, "URL2": { "name": "b" }, "URL3": { "name": "c" }, } WHat I would like to do is replace... (5 Replies)
Discussion started by: Junaid Subhani
5 Replies

6. Shell Programming and Scripting

UNIX or Perl script to convert JSON to CSV

Is there a Unix or Perl script that converts JSON files to CSV or tab delimited format? We are running AIX 6.1. Thanks in advance! (1 Reply)
Discussion started by: warpmail
1 Replies

7. Shell Programming and Scripting

Bash script - cygwin (powershell?) pull from GitHub API Parse JSON

All, Have a weird issue where i need to generate a report from GitHub monthly detailing user accounts and the last time they logged in. I'm using a windows box to do this (work issued) and would like to know if anyone has any experience scripting for GitAPI using windows / cygwin / powershell?... (9 Replies)
Discussion started by: ChocoTaco
9 Replies

8. Shell Programming and Scripting

How to define a variable in a BASH script by using a JSON file online?

Hello, I would like to modify an existing script of mine that uses a manually defined "MCVERSION" variable and make it define that variable instead based on this JSON file stored online: https://s3.amazonaws.com/Minecraft.Download/versions/versions.json Within that JSON, I 'm looking for... (4 Replies)
Discussion started by: nbsparks
4 Replies

9. Shell Programming and Scripting

BASH SCRIPT of LS command

I need help in writing a BASH SCRIPT of ls command. for example: $ ./do_ls.sh files f1.txt f2.jpeg f3.doc $ ./do_ls.sh dirs folder1 folder2 folder3 My attempt: #!/bin/bash # if test $# -d file then echo $dirs else (3 Replies)
Discussion started by: above8k
3 Replies

10. Shell Programming and Scripting

Building command line parameters of arbitrary length

I couldn't find an existing thread that addressed this question, so hopefully this isn't redundant with anything previously posted. Here goes: I am writing a C-Shell script that runs a program that takes an arbitrary number of parameters: myprog -a file1 \ -b file2 \ -c file3 ... \ -n... (2 Replies)
Discussion started by: cmcnorgan
2 Replies

Featured Tech Videos