To get the JSON data used in each `curl` statement while using `xargs` and map it to its corresponding result, you can use a combination of `xargs` and `jq`, a lightweight and flexible command-line JSON processor. Here's a step-by-step guide:
Assuming you have a file containing a list of JSON data (one JSON object per line) and you want to make a `curl` request with each JSON object and then map the response to the original input:
1. **Create a file with JSON data**:
You should have a file (e.g., `input.json`) with one JSON object per line. For example:
```json
{"id": 1, "name": "John"}
{"id": 2, "name": "Jane"}
{"id": 3, "name": "Bob"}
```
2. **Use `xargs` with `curl` and `jq`**:
You can use the `xargs` command along with `curl` and `jq` to make the `curl` request for each line of JSON data and then process the response. Here's a command that does this:
```bash
cat input.json | xargs -I {} -P 4 sh -c 'echo "{}" | curl -s -X POST -H "Content-Type: application/json" -d @- https://example.com/api/endpoint | jq -s .'
```
Let's break down the command:
- `cat input.json`: This reads the lines of JSON data from the `input.json` file.
- `xargs -I {} -P 4`: This processes each line of JSON data in parallel (adjust the number of parallel processes with the `-P` option).
- `sh -c '...'`: This is used to execute a shell command, which is enclosed in single quotes.
- `echo "{}" | curl ...`: This sends the JSON data to the specified URL using `curl`.
- `curl -s -X POST -H "Content-Type: application/json" -d @- https://example.com/api/endpoint`: This is the `curl` command that posts the JSON data to the API endpoint.
- `jq -s .`: This processes the response using `jq` and outputs the result. You can customize the `jq` filter according to your JSON structure.
The above command will make a `curl` request for each line of JSON data and use `jq` to process the response for each request, preserving the mapping of input to output. The `-P` option in `xargs` allows for parallel processing to improve performance.
Make sure to adjust the `curl` options and URL to match your specific use case.