fix: more robustness in http handling (#4)

* fix: more robustness in http handling

* Update lib/utils.py

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* add missing import

* fix timeout

* readme

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: jiacai2050

.github/workflows/release.yml

@@ -2,7 +2,7 @@
 
 # asdf-zig [![Build](https://github.com/zigcc/asdf-zig/actions/workflows/build.yml/badge.svg)](https://github.com/zigcc/asdf-zig/actions/workflows/build.yml)
 
-[asdf-zig](https://github.com/zigcc/asdf-zig) plugin for the [asdf version manager](https://asdf-vm.com).
+[Zig](http://ziglang.org/) plugin for the [asdf version manager](https://asdf-vm.com).
 
 </div>
 
@@ -13,7 +13,7 @@
 
 # Install
 
-First add asdf-zig as plugin:
+After installing [asdf](https://asdf-vm.com/guide/getting-started.html), install the plugin by running:
 
 ```shell
 asdf plugin add zig https://github.com/zigcc/asdf-zig.git

.github/workflows/semantic-pr.yml

@@ -7,12 +7,14 @@
 import sys
 import urllib.request
 from urllib.parse import urljoin
+from urllib.error import HTTPError
 import json
 import hashlib
 import logging
 
 INDEX_URL = os.getenv("ASDF_ZIG_INDEX_URL", "https://ziglang.org/download/index.json")
 HTTP_TIMEOUT = int(os.getenv("ASDF_ZIG_HTTP_TIMEOUT", "30"))
+USER_AGENT = "asdf-zig (https://github.com/zigcc/asdf-zig)"
 
 # https://github.com/mlugg/setup-zig/blob/main/mirrors.json
 # If any of these mirrors are down, please open an issue!
@@ -32,17 +34,30 @@
     "arm64": "aarch64",
 }
 
+class HTTPAccessError(Exception):
+    def __init__(self, url, code, reason, body):
+        super().__init__(f"{url} access failed, code:{code}, reason:{reason}, body:{body}")
+        self.url = url
+        self.code = code
+        self.reason = reason
+        self.body = body
+
+def http_get(url, timeout=HTTP_TIMEOUT):
+    try:
+        req = urllib.request.Request(url, headers={'User-Agent': USER_AGENT})
+        return urllib.request.urlopen(req, timeout=timeout)
+    except HTTPError as e:
+        body = e.read().decode("utf-8")
+        raise HTTPAccessError(url, e.code, e.reason, body)
 
 def fetch_index():
-    with urllib.request.urlopen(INDEX_URL, timeout=HTTP_TIMEOUT) as response:
-        if response.getcode() == 200:
-            body = response.read().decode("utf-8")
-            return json.loads(body)
-        else:
-            raise Exception(f"Fetch index.json error: {response.getcode()}")
+    with http_get(INDEX_URL) as response:
+        body = response.read().decode("utf-8")
+        return json.loads(body)
 
 
-def all_versions(index=fetch_index()):
+def all_versions():
+    index = fetch_index()
     versions = [k for k in index.keys() if k != "master"]
     versions.sort(key=lambda v: tuple(map(int, v.split("."))))
     return versions
@@ -52,10 +67,7 @@ def download_and_check(url, out_file, expected_shasum, total_size):
     logging.info(f"Begin download tarball({total_size}) from {url} to {out_file}...")
     chunk_size = 1024 * 1024 # 1M chunks
     sha256_hash = hashlib.sha256()
-    with urllib.request.urlopen(url, timeout=HTTP_TIMEOUT) as response:
-        if response.getcode() != 200:
-            raise Exception(f"Fetch index.json error: {response.getcode()}")
-
+    with http_get(url) as response:
         read_size = 0
         with open(out_file, "wb") as f:
             while True:
@@ -113,7 +125,7 @@ def download(version, out_file):
 
 
 def main(args):
-    command = args[0] if args else "default"
+    command = args[0] if args else "all-versions"
     if command == "all-versions":
         versions = all_versions()
         print(" ".join(versions))