(#373) Ensure that release is located correctly

There is no method in Octockit to find a release by a name, only by
a tag. GRM, previously, had a method to filter a returned list of
releases to find the one with the given name, however, this was
incorrectly refactored out, and work had to be done to put it back in
place. Found during testing on Twitch stream.

Author: gep13

src/GitReleaseManager.Core/Provider/GitHubProvider.cs

@@ -254,7 +254,14 @@ public Task<Release> GetReleaseAsync(string owner, string repository, string tag
         {
             return ExecuteAsync(async () =>
             {
-                var release = await _gitHubClient.Repository.Release.Get(owner, repository, tagName).ConfigureAwait(false);
+                // This method wants to return a single Release, that has the tagName that is requested.
+                // The obvious thing to do here would be to use Repository.Release.Get, however, this doesn't
+                // return a release if it hasn't been published yet.  As a result, we have to get all of them,
+                // and then filter down to the required tagName. This isn't very efficient, and would love to
+                // have a better approach, but for now, this does the job.
+                var releases = await _gitHubClient.Repository.Release.GetAll(owner, repository).ConfigureAwait(false);
+
+                var release = releases.FirstOrDefault(r => r.TagName == tagName);
 
                 return _mapper.Map<Release>(release);
             });

src/GitReleaseManager.Core/VcsService.cs

@@ -68,10 +68,19 @@ private async Task<Release> CreateReleaseAsync(string owner, string repository,
         {
             Release release;
 
-            try
+            release = await _vcsProvider.GetReleaseAsync(owner, repository, tagName).ConfigureAwait(false);
+
+            if (release == null)
             {
-                release = await _vcsProvider.GetReleaseAsync(owner, repository, tagName).ConfigureAwait(false);
+                release = CreateReleaseModel(name, tagName, body, prerelease, targetCommitish);
+
+                _logger.Verbose("Creating new release with tag '{TagName}' on '{Owner}/{Repository}'", tagName, owner, repository);
+                _logger.Debug("{@Release}", release);
 
+                release = await _vcsProvider.CreateReleaseAsync(owner, repository, release).ConfigureAwait(false);
+            }
+            else
+            {
                 if (!release.Draft && !_configuration.Create.AllowUpdateToPublishedRelease)
                 {
                     throw new InvalidOperationException($"Release with tag '{tagName}' not in draft state, so not updating");
@@ -85,15 +94,6 @@ private async Task<Release> CreateReleaseAsync(string owner, string repository,
 
                 await _vcsProvider.UpdateReleaseAsync(owner, repository, release).ConfigureAwait(false);
             }
-            catch (NotFoundException)
-            {
-                release = CreateReleaseModel(name, tagName, body, prerelease, targetCommitish);
-
-                _logger.Verbose("Creating new release with tag '{TagName}' on '{Owner}/{Repository}'", tagName, owner, repository);
-                _logger.Debug("{@Release}", release);
-
-                release = await _vcsProvider.CreateReleaseAsync(owner, repository, release).ConfigureAwait(false);
-            }
 
             await AddAssetsAsync(owner, repository, tagName, assets).ConfigureAwait(false);