Building JSON command with bash script


 
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# 29  
Old 09-25-2019
With some more mucking around, I now have a version without eval that also escapes the reserved JSON characters:

Code:
#!/bin/bash
mk_json_object(){
   local items rest

   printf -v items '  "%s": "%s"' $(json_quote "$1" "$2")
   shift 2
   [ $# -gt 1 ] && printf -v rest ',\n  "%s": "%s"' $(json_quote "$@")
   printf "{\n%s\n}\n" "$items$rest"
}

mk_json_lst(){
   local list rest
   printf -v list '  "%s"' $(json_quote "$1")
   shift
   [ $# -gt 0 ] && printf -v rest ',\n  "%s"' $(json_quote "$@")
   printf "[\n%s\n]\n" "$list$rest"
}

json_quote() {
    while [ $# -gt 0 ]
    do
        val=${1//\\/\\\\}
        val=${val//\"/\\\"}
        val=${val//$'\n'/\\\n}
        val=${val//$'\t'/\\\t}
        val=${val//$'\r'/\\\r}
        val=${val//$'\f'/\\\f}
        val=${val//$'\b'/\\\b}
        printf "%s" "$val"
        shift
        [ $# -gt 0 ] && printf " "
    done
}

mk_json_object_one_val() {
        local key=$1
        while [ $# -gt 1 ]
        do
            shift
            args=( "${args[@]}" "$key" "$1" )
        done
        mk_json_object "${args[@]}"
}

mk_json_object_one_val '$(uname)' "key
1" '"test"' more$'\r'
mk_json_lst test$'\b' key-2

output:
Code:
{
  "$(uname)": "key\n1",
  "$(uname)": "\"test\"",
  "$(uname)": "more\r"
}
[
  "test\b",
  "key-2"
]

Note there are some extra space and newline characters added to the output in mk_json_object() and mk_json_lst() that you many want to remove if you a building variables to send as paramters to another program.

--- Post updated at 09:50 AM ---

Quote:
Originally Posted by psysc0rpi0n
Now, according to the examples from bitcoin core:
Code:
> bitcoin-cli sendmany "" "{\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\":0.01,\"1353tsE8YMTA4EuV7dgUXGjNFf9KpVvKHz\":0.02}" 1 "" "[\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\",\"1353tsE8YMTA4EuV7dgUXGjNFf9KpVvKHz\"]"

So the functions outputs are not matching exactly the docs example. The thing is that the docs example wouldn't also pass in a json checker tool like jsonlint. This said,I think the backslashes escaping the inner double quotes of each address can be removed.

Now, there is a question that might be asked at this point. Will these backslashes be handled by bitcoin core and removed later to pass the command to the RPC server? Are they really needed? I would take a chance in saying they are not needed.
These escaped quotes are simply to protect them from the shell the actual argument values that will react the bitcoin-cli process will be

Code:
1:sendmany
2:
3:{"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX":0.01,"1353tsE8YMTA4EuV7dgUXGjNFf9KpVvKHz":0.02}
4:1
5:
6:["1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX","1353tsE8YMTA4EuV7dgUXGjNFf9KpVvKHz"]


Last edited by Chubler_XL; 09-25-2019 at 08:00 PM..
This User Gave Thanks to Chubler_XL For This Post:
# 30  
Old 09-25-2019
But I still need to understand something else. But it's something related with the way bitcoin core processes the command.

Stomp functions don't add any backslashes and the script don't return any script related errors. The error returned is from bitcoin core which complains about insufficient funds. However, when I tried to run the commands above manually without the backslashes, bitcoin core complained about json parsing error. So, why running the command by hand with no backslashes, produces errors and running the command without backslashes using the script, don't produce any errors (related with the script code)????

Tomorrow I need to look into this new issue!

ok, enough for today. Time to sleep.

Thanks to both of you.

Last edited by psysc0rpi0n; 09-25-2019 at 08:09 PM..
# 31  
Old 09-25-2019
Quote:
Originally Posted by psysc0rpi0n
But I still need to understand something else. But it's something related with the way bitcoin core processes the command.

Stomp functions don't add any backslashes and the script don't return any script related errors. The error returned is from bitcoin core which complains about insufficient funds. However, when I tried to run the commands above manually without the backslashes, bitcoin core complained about json parsing error. So, why running the command by hand with no backslashes, produces errors and running the command without backslashes using the script, don't produce any errors (related with the script code)????

Tomorrow I need to look into this new issue!

ok, enough for today. Time to sleep.

Thanks to both of you.
The reason for this is that quote removal only occurs on the original input words, not the result of expansions. To demonstrate:

Code:
$ echo "Hello, world"
Hello, world
$ VAR='echo "Hello, world"'
$ $VAR
"Hello, world"

It's also worth noting that quote matching is done before any expansion, for example:
Code:
$ QT='"'
$ echo "$QT"
"
$ echo $QT
"

If you save this code a pparam(or make it a function in your script) you can use it to debug what the shell is doing to your parameters before they are passed on to scripts/functions:

Code:
for((i=1;i<=${#};i++))
do
   echo Param $i: ${!i}
done

Code:
$ VAR='"one" "two"'
$ ./pparam $VAR
Param 1: "one"
Param 2: "two"
$ ./pparam "$VAR"
Param 1: "one" "two"
$ ./pparam "one" "two"
Param 1: one
Param 2: two

These 3 Users Gave Thanks to Chubler_XL For This Post:
# 32  
Old 09-26-2019
Quote:
Attempt 3 - readded backslashes because it's clear that they are needed.
Code:
bitcoin-cli -testnet sendmany "" "{\"n1yswZYByRv3okGDHs1oDaevq8gsDaYZzC\":"0.079319635", \"2NFafKRugHFdYEib7xVfkT6bvtkUKK8oShZ\":"0.079319635"}" 6 "Payments" "[\"n1yswZYByRv3okGDHs1oDaevq8gsDaYZzC\", \"2NFafKRugHFdYEib7xVfkT6bvtkUKK8oShZ\"]" true 6 CONSERVATIVE

Result:
Code:
error code: -3
error message:
Invalid amount

I think that is also wrong quoting, because the amounts are not escaped(prepended with slashes). But this causes no errors, because numbers should not be quoted in json. Maybe it will cause an error if you fix the quoting. :-)
# 33  
Old 09-26-2019
Quote:
Originally Posted by stomp
Code:
bitcoin-cli -testnet sendmany "" "{\"n1yswZYByRv3okGDHs1oDaevq8gsDaYZzC\":"0.079319635", \"2NFafKRugHFdYEib7xVfkT6bvtkUKK8oShZ\":"0.079319635"}" 6 "Payments" "[\"n1yswZYByRv3okGDHs1oDaevq8gsDaYZzC\", \"2NFafKRugHFdYEib7xVfkT6bvtkUKK8oShZ\"]" true 6 CONSERVATIVE

Result:
Code:
error code: -3
error message:
Invalid amount

I think that is also wrong quoting, because the amounts are not escaped(prepended with slashes). But this causes no errors, because numbers should not be quoted in json. Maybe it will cause an error if you fix the quoting. :-)
In bitcoin core docs, says that the amount can be strings too.

Later after work, I'll look into this.
Thanks
Psy
# 34  
Old 09-26-2019
Quote:
Originally Posted by Chubler_XL

...

These escaped quotes are simply to protect them from the shell the actual argument values that will react the bitcoin-cli process will be
Ok, I'm going to try your examples. This is not trivial for a starter. I've just been reading but not practicing much, so this is not clear at first sight!

--- Post updated at 10:02 PM ---

Quote:
Originally Posted by Chubler_XL
The reason for this is that quote removal only occurs on the original input words, not the result of expansions. To demonstrate:

Code:
$ echo "Hello, world"
Hello, world
$ VAR='echo "Hello, world"'
$ $VAR
"Hello, world"

It's also worth noting that quote matching is done before any expansion, for example:
Code:
$ QT='"'
$ echo "$QT"
"
$ echo $QT
"

If you save this code a pparam(or make it a function in your script) you can use it to debug what the shell is doing to your parameters before they are passed on to scripts/functions:

Code:
for((i=1;i<=${#};i++))
do
   echo Param $i: ${!i}
done

Code:
$ VAR='"one" "two"'
$ ./pparam $VAR
Param 1: "one"
Param 2: "two"
$ ./pparam "$VAR"
Param 1: "one" "two"
$ ./pparam "one" "two"
Param 1: one
Param 2: two

I don't fully understand what you mean by:
Quote:
that quote removal only occurs on the original input words, not the result of expansions.
and
Quote:
It's also worth noting that quote matching is done before any expansion, for example:
.

I need to read about expansions!
# 35  
Old 09-26-2019
I finally reached my goal...

Some changes in the script in the meantime.

I share the link in github:
TugaRevoBTC/TugaRevoTestnet.sh at master . PsySc0rpi0n/TugaRevoBTC . GitHub

Edited;
But this is not over... Heheh
I'll be doing some changes and I'll be doing tutorials and asking questions here.

Last edited by psysc0rpi0n; 09-27-2019 at 05:00 AM..
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