[wasm] Use chromium dash to get the versions, instead of the obsoleted

.. omahaproxy.

The older way to get versions hasn't been removed yet, to wait to see
how stable this method is.

Author: radical

eng/testing/bump-chrome-version.proj

@@ -17,7 +17,7 @@
     </GetChromeVersions>
 
     <GetChromeVersions
-                OSIdentifier="win"
+                OSIdentifier="Windows"
                 OSPrefix="Win_x64"
                 Channel="$(ChromeChannel)"
                 MaxMajorVersionsToCheck="1"

eng/testing/wasm-provisioning.targets

@@ -5,8 +5,8 @@
     -->
     <ChromeChannel>stable</ChromeChannel>
 
-    <ChromeOSIdentifier Condition="$([MSBuild]::IsOSPlatform('windows'))">win</ChromeOSIdentifier>
-    <ChromeOSIdentifier Condition="$([MSBuild]::IsOSPlatform('linux'))">linux</ChromeOSIdentifier>
+    <ChromeOSIdentifier Condition="$([MSBuild]::IsOSPlatform('windows'))">Windows</ChromeOSIdentifier>
+    <ChromeOSIdentifier Condition="$([MSBuild]::IsOSPlatform('linux'))">Linux</ChromeOSIdentifier>
     <ChromeOSIdentifier Condition="'$(ChromeOSIdentifier)' == ''">unsupported-platform</ChromeOSIdentifier>
 
     <!-- disable by default on unsupported platforms -->

src/tasks/WasmBuildTasks/GetChromeVersions.cs

@@ -18,6 +18,7 @@ namespace Microsoft.WebAssembly.Build.Tasks;
 
 public class GetChromeVersions : MBU.Task
 {
+    private const string s_fetchReleasesUrl = "https://chromiumdash.appspot.com/fetch_releases?channel={0}&num=1";
     private const string s_allJsonUrl = "http://omahaproxy.appspot.com/all.json";
     private const string s_snapshotBaseUrl = $"https://storage.googleapis.com/chromium-browser-snapshots";
     private const string s_historyUrl = $"https://omahaproxy.appspot.com/history";
@@ -66,9 +67,10 @@ private async Task<bool> ExecuteInternalAsync()
 
         try
         {
-            (ChromeVersionSpec version, string baseUrl) = await FindVersionFromHistoryAsync().ConfigureAwait(false);
+            //(ChromeVersionSpec version, string baseUrl) = await FindVersionFromHistoryAsync().ConfigureAwait(false);
             // For using all.json, use this instead:
             // (ChromeVersionSpec version, string baseUrl) = await FindVersionFromAllJsonAsync().ConfigureAwait(false);
+            (ChromeVersionSpec version, string baseUrl) = await FindVersionFromChromiumDash().ConfigureAwait(false);
 
             BaseSnapshotUrl = baseUrl;
             ChromeVersion = version.version;
@@ -167,6 +169,34 @@ async IAsyncEnumerable<string> GetVersionsAsync()
         }
     }
 
+    private async Task<(ChromeVersionSpec version, string baseSnapshotUrl)> FindVersionFromChromiumDash()
+    {
+        using Stream stream = await GetDownloadFileStreamAsync("fetch_releases.json", string.Format(s_fetchReleasesUrl, Channel)).ConfigureAwait(false);
+
+        ChromiumDashRelease[]? releases = await JsonSerializer
+                                                    .DeserializeAsync<ChromiumDashRelease[]>(stream)
+                                                    .ConfigureAwait(false);
+        if (releases is null)
+            throw new LogAsErrorException($"Failed to read chrome versions from {s_fetchReleasesUrl}");
+
+        ChromiumDashRelease? foundRelease = releases.Where(rel => string.Equals(rel.platform, OSIdentifier, StringComparison.InvariantCultureIgnoreCase)).SingleOrDefault();
+        if (foundRelease is null)
+        {
+            string availablePlatformIds = string.Join(", ", releases.Select(rel => rel.platform).Distinct().Order());
+            throw new LogAsErrorException($"Unknown Platform '{OSIdentifier}'. Platforms found " +
+                                            $"in fetch_releases.json: {availablePlatformIds}");
+        }
+
+        ChromeVersionSpec versionSpec = new(foundRelease.platform,
+                                            Channel,
+                                            foundRelease.version,
+                                            foundRelease.chromium_main_branch_position.ToString(),
+                                            foundRelease.version);
+        string? baseSnapshotUrl = await FindSnapshotUrlFromBasePositionAsync(versionSpec, throwIfNotFound: true)
+                                        .ConfigureAwait(false);
+        return (versionSpec, baseSnapshotUrl!);
+    }
+
     private async Task<(ChromeVersionSpec versionSpec, string baseSnapshotUrl)> FindVersionFromAllJsonAsync()
     {
         using Stream stream = await GetDownloadFileStreamAsync("all.json", s_allJsonUrl).ConfigureAwait(false);
@@ -271,6 +301,8 @@ private async Task<Stream> GetDownloadFileStreamAsync(string filename, string ur
         return null;
     }
 
+    private sealed record ChromiumDashRelease(string channel, int chromium_main_branch_position, string milesone, string platform, string version);
+
     private sealed record PerOSVersions(string os, ChromeVersionSpec[] versions);
     private sealed record ChromeVersionSpec(string os, string channel, string version, string branch_base_position, string v8_version);
     private sealed record ChromeDepsVersionSpec(string chromium_version, string chromium_base_position, string v8_version)