Read And Update JSON File Using nsJSON Plugin (NSIS) - nsis

Question

I am trying to update one data on JSON file using nsJson Plugin.
My JSON data on File
{ "header_left_lebel": "LEFT LEBEL",
"header_center_label": "CENTER LEBEL",
"base_path": "E:\Workspace\my-demo-app"
}
I want to edit the base path during installation of the application.
My Code to Read and Update the Value
Section "Installation Section"
SetOutPath "$INSTDIR"
GetFullPathName $0 ..
StrCpy $installationPath "$0\${applicationName}";This Holds the installation path
nsJSON::Set /file `$installationPath/config/settings.json`
nsJSON::Set `base_path` /value `"$installationPath"`
nsJSON::Serialize /file `$installationPath/config/settings.json`
WriteUninstaller "$INSTDIR\Uninstall.exe"
SectionEnd
The above code updates the JSON file but it only keeps base_path
I want to keep all the data and only to update base_path
Any help or links will be appreciated.

Answer 1

Your code works correctly for me when using NSIS v3.04 and JSON plug-in v1.1.1.0 (November 2017):
Unicode True
!macro DumpTxtFile file
Push "${file}"
Call DumpTxtFile
!macroend
Function DumpTxtFile
Exch $0
Push $1
FileOpen $0 $0 r
loop:
ClearErrors
FileRead $0 $1
IfErrors done
DetailPrint $1
Goto loop
done:
FileClose $0
Pop $1
Pop $0
FunctionEnd
!include LogicLib.nsh
Section
FileOpen $0 "$temp\NSIStest.json" w
FileWrite $0 '{ "header_left_lebel": "LEFT LEBEL",$\r$\n'
FileWrite $0 ' "header_center_label": "CENTER LEBEL",$\r$\n'
FileWrite $0 ' "base_path": "E:\Workspace\my-demo-app"$\r$\n'
FileWrite $0 '}'
FileClose $0
!insertmacro DumpTxtFile "$temp\NSIStest.json"
Var /Global installationPath
StrCpy $installationPath "c:\dummy\path"
ClearErrors
nsJSON::Set /file `$temp\NSIStest.json`
nsJSON::Set `base_path` /value `"$installationPath"`
nsJSON::Serialize /format /file `$temp\NSIStest.json`
${If} ${Errors}
Abort "Unable to update JSON file!"
${EndIf}
!insertmacro DumpTxtFile "$temp\NSIStest.json"
SectionEnd