Add timeout and gh-proxy fallback for git source installs

docs/arm64.md

@@ -53,5 +53,9 @@ run on Windows ARM64.
 - **No checksum is verified.** Git history is the integrity check.
 - **No `-arm64` variants for legacy releases.** Versions without architecture
   metadata (such as `2.10.0`) keep their existing x64-only behavior.
-- **Mirrors don't apply.** `FLUTTER_STORAGE_BASE_URL` (see `mirror.md`) only
-  affects archive downloads; source installs clone from GitHub.
+- **Mirrors don't apply to archive downloads.** `FLUTTER_STORAGE_BASE_URL`
+  (see `mirror.md`) only affects archive downloads; source installs clone
+  from GitHub. If GitHub sends no data within 10s, the plugin
+  automatically falls back to the `https://gh-proxy.org/` mirror and shows
+  a countdown while probing. Once the transfer starts it is never
+  interrupted.

docs/mirror.md

@@ -48,3 +48,11 @@ $env:FLUTTER_STORAGE_BASE_URL = "https://storage.flutter-io.cn"
 ```powershell
 [Environment]::SetEnvironmentVariable('FLUTTER_STORAGE_BASE_URL', 'https://storage.flutter-io.cn', 'Machine')
 ```
+
+## GitHub mirror for source installs
+
+On Linux ARM64 and Windows ARM64,
+the plugin installs Flutter from git source instead of a prebuilt archive.
+If `https://github.com` sends no data within 10s,
+the plugin automatically falls back to `https://gh-proxy.org/`.
+Once the transfer starts it is never interrupted.

hooks/available.lua

@@ -10,7 +10,7 @@ require("util")
 local function releases(type)
     local resp, err
     for attempt = 1, MAX_ATTEMPTS do
-        resp, err = http.get({ url = BASE_URL:format(type.osType) })
+        resp, err = http.get({ url = getReleasesUrl(type.osType) })
         if resp ~= nil and resp.status_code == 200 then
             return json.decode(resp.body)
         end

hooks/pre_install.lua

@@ -16,7 +16,7 @@ function PLUGIN:PreInstall(ctx)
     local channelKey
     if arg == "beta" or arg == "dev" or arg == "stable" then
         local resp, err = http.get({
-            url = BASE_URL:format(platform.osType)
+            url = getReleasesUrl(platform.osType)
         })
         if err ~= nil or resp.status_code ~= 200 then
             error("get version failed: " .. tostring(err) .. " (status " .. tostring(resp and resp.status_code) .. ")")

lib/git.lua

@@ -3,7 +3,10 @@ local FALLBACK_HOME_ENV = { "HOME", "USERPROFILE" }
 local VFOX_DIR = ".vfox"
 local TMP_DIR = "tmp"
 local ENGINE_PIN = "bin/internal/engine.version"
+local FETCH_TIMEOUT = 10
 local FETCH_ATTEMPTS = 3
+local GH_PROXY_PREFIX = "https://gh-proxy.org/"
+local GH_BASE = "https://github.com/"
 
 local M = {}
 
@@ -34,6 +37,129 @@ local function localPath(path)
     return path:gsub("/", sep())
 end
 
+local function isGithubUrl(url)
+    return type(url) == "string" and url:sub(1, #GH_BASE) == GH_BASE
+end
+
+local B64CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
+
+local function base64(data)
+    local out = {}
+    for i = 1, #data, 3 do
+        local a = data:byte(i)
+        local b = data:byte(i + 1) or 0
+        local c = data:byte(i + 2) or 0
+        local n = a * 65536 + b * 256 + c
+        out[#out + 1] = B64CHARS:sub(math.floor(n / 262144) % 64 + 1, math.floor(n / 262144) % 64 + 1)
+            .. B64CHARS:sub(math.floor(n / 4096) % 64 + 1, math.floor(n / 4096) % 64 + 1)
+        if i + 1 > #data then
+            out[#out + 1] = "=="
+        elseif i + 2 > #data then
+            out[#out + 1] = B64CHARS:sub(math.floor(n / 64) % 64 + 1, math.floor(n / 64) % 64 + 1) .. "="
+        else
+            out[#out + 1] = B64CHARS:sub(math.floor(n / 64) % 64 + 1, math.floor(n / 64) % 64 + 1)
+                .. B64CHARS:sub(n % 64 + 1, n % 64 + 1)
+        end
+    end
+    return table.concat(out)
+end
+
+-- PowerShell -EncodedCommand needs UTF-16LE. The script is ASCII-only, so
+-- interleaving NUL bytes is sufficient.
+local function utf16le(data)
+    return data:gsub("(.)", "%1" .. string.char(0))
+end
+
+-- Probe whether the remote answers within the timeout. Success means the
+-- first byte arrived: once the transfer starts, the real fetch below runs
+-- without a timeout and is never interrupted.
+local function probeWithTimeoutUnix(remote, ref, timeout)
+    local gitCmd = "git ls-remote --exit-code " .. quote(remote) .. " " .. quote(ref)
+    -- Note: %%s becomes %s for the shell, %d is the Lua format arg for timeout
+    local script = string.format(
+        [[tmp=$(mktemp /tmp/vfox_probe_XXXXXX)
+start=$(date +%%s)
+end=$((start + %d))
+%s >"$tmp" 2>/dev/null &
+pid=$!
+while kill -0 $pid 2>/dev/null; do
+    if [ -s "$tmp" ]; then
+        kill $pid 2>/dev/null
+        wait $pid 2>/dev/null
+        rm -f "$tmp"
+        printf "\r%%*s\r" 40 ""
+        printf "\n"
+        exit 0
+    fi
+    now=$(date +%%s)
+    remaining=$((end - now))
+    if [ $remaining -le 0 ]; then
+        kill $pid 2>/dev/null
+        wait $pid 2>/dev/null
+        rm -f "$tmp"
+        printf "\r%%*s\r" 40 ""
+        printf "\n"
+        exit 124
+    fi
+    printf "\rTimeout in %%3ds... " $remaining
+    sleep 1
+done
+wait $pid
+rc=$?
+rm -f "$tmp"
+printf "\r%%*s\r" 40 ""
+printf "\n"
+exit $rc
+]], timeout, gitCmd)
+    return exec(script)
+end
+
+local function probeWithTimeoutWindows(remote, ref, timeout)
+    -- The plugin runtime does not process shell quotes on Windows (a quoted
+    -- -File path arrives literally and fails with "Illegal characters in
+    -- path"), so the script is passed via -EncodedCommand instead: base64
+    -- has no spaces or quotes and survives any argv splitting.
+    local function psArg(value)
+        return '"' .. value:gsub('"', '""') .. '"'
+    end
+    local script = string.format([[
+$tmp = Join-Path ([IO.Path]::GetTempPath()) ("vfox_probe_" + $PID + ".out")
+$proc = Start-Process -FilePath "git" -ArgumentList @("ls-remote", "--exit-code", %s, %s) -RedirectStandardOutput $tmp -RedirectStandardError "NUL" -PassThru -NoNewWindow
+$deadline = (Get-Date).AddSeconds(%d)
+while (-not $proc.HasExited) {
+    if ((Test-Path $tmp) -and ((Get-Item $tmp).Length -gt 0)) {
+        try { $proc.Kill() } catch {}
+        Remove-Item -Force $tmp
+        Write-Host ""
+        exit 0
+    }
+    $remaining = [int]($deadline - (Get-Date)).TotalSeconds
+    if ($remaining -le 0) {
+        try { $proc.Kill() } catch {}
+        Remove-Item -Force $tmp -ErrorAction SilentlyContinue
+        Write-Host ""
+        exit 124
+    }
+    Write-Host -NoNewline ("`rTimeout in " + $remaining + " s... ")
+    Start-Sleep -Seconds 1
+}
+Remove-Item -Force $tmp -ErrorAction SilentlyContinue
+Write-Host ""
+exit $proc.ExitCode
+]], psArg(remote), psArg(ref), timeout)
+    return exec("powershell -NoProfile -NoLogo -ExecutionPolicy Bypass -EncodedCommand "
+        .. base64(utf16le(script)))
+end
+
+local function probeWithTimeout(remote, ref, timeout)
+    io.write(string.format("Connecting to %s (timeout: %ds)...\n", remote, timeout))
+    io.flush()
+    if RUNTIME.osType == "windows" then
+        return probeWithTimeoutWindows(remote, ref, timeout)
+    end
+    return probeWithTimeoutUnix(remote, ref, timeout)
+end
+
 function M.removeDir(path)
     if RUNTIME.osType == "windows" then
         exec('if exist "' .. path .. '" rmdir /s /q "' .. path .. '"')
@@ -93,7 +219,7 @@ function M.init(root)
     return git(root, "config core.longpaths true")
 end
 
-function M.fetch(root, remote, ref)
+local function fetchPlain(root, remote, ref)
     for _ = 1, FETCH_ATTEMPTS do
         if git(root, "fetch -q --depth 1 " .. remote .. " " .. ref) then
             return true
@@ -102,6 +228,25 @@ function M.fetch(root, remote, ref)
     return false
 end
 
+function M.fetch(root, remote, ref)
+    if not isGithubUrl(remote) then
+        return fetchPlain(root, remote, ref)
+    end
+    local remotes = { remote, GH_PROXY_PREFIX .. remote }
+    for i, url in ipairs(remotes) do
+        if probeWithTimeout(url, ref, FETCH_TIMEOUT) then
+            if fetchPlain(root, url, ref) then
+                return true
+            end
+        end
+        if i < #remotes then
+            io.write(string.format("Cannot reach %s, trying %s...\n", url, remotes[i + 1]))
+            io.flush()
+        end
+    end
+    return false
+end
+
 function M.checkoutHead(root)
     return git(root, "checkout -q FETCH_HEAD")
 end

lib/ohos.lua

@@ -2,11 +2,15 @@ local http = require("http")
 local json = require("json")
 local git = require("git")
 
+require("util")
+
 local MARKER = "-ohos-"
 local REPO = "CPF-Flutter/flutter_flutter"
 local RELEASES_URL = "https://gitcode.com/api/v5/repos/%s/releases?per_page=100"
 local CLONE_URL = "https://gitcode.com/%s.git"
 local NOTE = "OpenHarmony"
+local RELEASES_ATTEMPTS = 3
+local RETRY_DELAY = 10
 
 local M = {}
 
@@ -15,15 +19,23 @@ function M.isOhosVersion(version)
 end
 
 local function releases()
-    local resp, err = http.get({ url = RELEASES_URL:format(REPO) })
-    if err ~= nil or resp.status_code ~= 200 then
-        return nil, err or ("HTTP " .. tostring(resp.status_code))
-    end
-    local body = json.decode(resp.body)
-    if type(body) ~= "table" then
-        return nil, "the releases response is not a JSON array"
+    local lastErr = "unknown error"
+    for attempt = 1, RELEASES_ATTEMPTS do
+        local resp, err = http.get({ url = RELEASES_URL:format(REPO) })
+        if err == nil and resp ~= nil and resp.status_code == 200 then
+            local body = json.decode(resp.body)
+            if type(body) == "table" then
+                return body
+            end
+            lastErr = "the releases response is not a JSON array"
+        else
+            lastErr = err or ("HTTP " .. tostring(resp and resp.status_code))
+        end
+        if attempt < RELEASES_ATTEMPTS then
+            sleep(RETRY_DELAY)
+        end
     end
-    return body
+    return nil, lastErr
 end
 
 function M.list()

lib/util.lua

@@ -16,7 +16,9 @@ function getStorageBaseUrl()
     return DEFAULT_STORAGE_BASE_URL
 end
 
-BASE_URL = getStorageBaseUrl() .. "/flutter_infra_release/releases/releases_%s.json"
+function getReleasesUrl(osType)
+    return getStorageBaseUrl() .. "/flutter_infra_release/releases/releases_" .. osType .. ".json"
+end
 
 
 function getOsTypeAndArch()