About

This library makes it easier to work with local JSON files in Go. Has multiple handy abstractions to get, set & update JSON objects and arrays.
It is currently a Work In Progress, and I built it as I did not really find any library of the same exact working. If you just want to work with JSON objects in code, checkout:

• gjson
• sjson

Features currently built

• GetAllObjects
• GetObjectFromIndex
• SetAllObjects
• AppendObjectToArray
• AppendObjectToArrayDirect

Path Note: In all functions, the filePath works with both absolute as well as relative paths

GetAllObjects

• Returns all the contents from the file
• This function unmarshals the object directly into the variable passed (Does require passing the var by reference.)
• If datatype is unknown, passing in an interface{} would still give results.

func main() {
  var users []models.Users // Replace with the datatype required.

  err := GetAllObjects(filePath, &users)
  // Handle errors

  b, _ := json.MarshalIndent(users, "", "  ")
  fmt.Print(string(b))
}

GetObjectFromIndex

• Returns a single object from an array of objects
• Uses generics to take care of typesafety & autocomplete
• Would throw an error if the index passed does not exist
• If datatype is unknown, can pass in any or discard it altogether

func main() {

  v, err := GetObjectFromIndex[models.Users](filePath, 5)
  // Handle errors

  fmt.Print(v.Name)
}

SetAllObjects

• Clears out the entire contents of the file and replaces it with the given contents

// To be added

AppendObjectToArray

• Appends an object to the end of the array.
• Follows the RMW (Read-Modify-Write) approach. Reads the entire file into memory, modifies it and then writes the file contents back.
• Currently only works with the entire object array. Working on appending objects to array fields.

func main() {
  
  obj := models.Users{
    ID:       1,
    Name:     "Leanne Graham",
    Username: "Bret",
    Email:    "[email protected]",
    Address: models.Address{
      // ...
    }
  }

  err = AppendObjectToArray(filePath, obj)

  // optional generic can also be added if you are sure that the other objects in the array are also of the same type
  // err = AppendObjectToArray[models.Users](filePath, obj)

  // Handle errors
}

AppendObjectToArrayDirect

• Does the same thing as AppendObjectToArray
• But instead of reading all the filecontents into memory, appends it directly using some manipulation.
• Is recommended when the filesize is too large to be read into memory.

func main() {
  
  obj := models.Users{
    ID:       1,
    Name:     "Leanne Graham",
    Username: "Bret",
    Email:    "[email protected]",
    Address: models.Address{
      // ...
    }
  }

  err = AppendObjectToArrayDirect(filePath, obj)
  // Handle errors
}

---

Things to note:

• If need more control over updates, it is better to GetAllObjects, run the updates and then SetAllObjects
• The generics are used for type safety and JSON structure consistency. Can use any if the structure is unknown or doesnt matter

TODO:

• Check wrongdatatypes for GetAllObjects
• Test and add code example for SetAllObjects