Easy check to see if string exists in json file

Easy check json file

Prompt 1

what is the easiest way to check if something exists as a string in a json file and then do something based on the string exists or not.
so i have a videoids in json file, if it is found do nothing, otherwise execute command

Answer 1

Certainly! Here’s a simple way to check if a string (e.g., a video ID) exists in a JSON file, and then do something based on whether it exists or not.

Assuming your JSON file (let’s call it videoids.json) looks like this:

{  
  "videoids": ["abc123", "def456", "ghi789"]  
}  

Python Example

import json  
  
video_id_to_check = "xyz000"  
  
with open('videoids.json', 'r') as f:  
    data = json.load(f)  
  
if video_id_to_check in data.get("videoids", []):  
    print("Video ID exists. Do nothing.")  
else:  
    print("Video ID not found. Executing command...")  
    # Place your command here, e.g.:  
    # os.system('your-command-here')  

Explanation:

• Load the JSON file.
• Check if the string is in the list.
• Do something if it’s not found.

---

Bash/JQ Example

If you want to do this in bash using jq:

video_id_to_check="xyz000"  
if jq -e --arg id "$video_id_to_check" '.videoids | index($id)' videoids.json > /dev/null; then  
  echo "Video ID exists. Do nothing."  
else  
  echo "Video ID not found. Executing command..."  
  # your command here  
fi  

---

Summary:

• Load the JSON.
• Check if the string is present.
• Take action based on the result.

Let me know if you need this in another language or with a different JSON structure!

Prompt 2

can i just use grep ?

Answer 2

Great question! Yes, you can use grep for a quick-and-dirty check, but there are some caveats:

Using grep to Check for a String in a JSON File

If your JSON file is simple (like your example), you can use grep to check if the string exists:

video_id_to_check="xyz000"  
if grep -q "$video_id_to_check" videoids.json; then  
  echo "Video ID exists. Do nothing."  
else  
  echo "Video ID not found. Executing command..."  
  # your command here  
fi  

Caveats:

• grep just searches for the string anywhere in the file. It doesn’t understand JSON structure.
• If your video IDs are unique and don’t appear as substrings elsewhere, this is usually fine.
• If you want to be more precise (e.g., avoid matching "xyz0001" when searching for "xyz000"), you can use word boundaries or more specific patterns, but it’s still not as robust as using jq or a proper JSON parser.

Example with word boundaries:

if grep -qw "\"$video_id_to_check\"" videoids.json; then  
  # The -w flag matches whole words, and the quotes help match the exact string in JSON array  
  echo "Video ID exists. Do nothing."  
else  
  echo "Video ID not found. Executing command..."  
fi  

Summary

• grep is fast and easy for simple checks.
• For more complex or reliable checks (especially with nested or large JSON), use jq or a proper parser.