Shell函数接收请求方法参数后异常：curl解析错误与重复输出

Alright, let's break down exactly what's causing the curl: (6) Could not resolve host: GET error and the duplicate 30 count:

The Core Issue: Duplicate $@ Usage #

Your modified mycurl function uses "$@" twice in the curl command, which completely messes up argument parsing.

When you call mycurl GET https://api.layer.com/apps/9d649224-cde5-11e7-b916-f3d1a15f96fe/exports, the "$@" variable expands to the full list of arguments you passed: GET https://api.layer.com/....

This turns your curl command into:

curl -X GET https://api.layer.com/... \
 -H 'Accept: application/vnd.layer+json; version=3.0' \
 -H 'Authorization: Bearer qFyBLjM9mhOlIwjZCeblbV9CrLZh2rqNzVIlIuf8a07UBj5F' \
 -H 'Content-Type: application/json' \
 GET https://api.layer.com/...

1. The "Could not resolve host: GET" Error #

Curl follows the syntax curl [options] URL.... After processing the first valid URL (https://api.layer.com/...), it treats the remaining GET as a second URL to request. Since GET isn't a valid hostname (there's no DNS record for it), curl throws the "Could not resolve host" error.

2. The Duplicate 30 Count #

Notice that after the GET "URL" fails, curl still processes the final https://api.layer.com/... argument as a third URL. That means you're actually sending two valid GET requests to the API: once from the first URL, once from the last.

Both requests return the same data, so when you parse the combined output with jq -r '.|length', you get two separate 30 values. The echo $count command then prints both numbers together.

How to Fix It #

You need to separate the request method from the rest of the arguments. Here's the corrected mycurl function:

mycurl() {
  # Capture the first argument as the HTTP method
  local http_method="$1"
  # Remove the first argument from the list, leaving only the URL/extra options
  shift
  curl -X "$http_method" \
    -H 'Accept: application/vnd.layer+json; version=3.0' \
    -H 'Authorization: Bearer qFyBLjM9mhOlIwjZCeblbV9CrLZh2rqNzVIlIuf8a07UBj5F' \
    -H 'Content-Type: application/json' \
    "$@"
}

• local http_method="$1" grabs the first argument (your HTTP method like GET or POST).
• shift removes that first argument from the argument list, so "$@" now only contains the URL and any extra curl options you might pass later.
• Now curl will only send one request to the correct URL, eliminating both the error and duplicate counts.

内容的提问来源于stack exchange，提问作者frigocat