More stuff

Author: DilumAluthge

src/VersionsJSONUtil.jl

@@ -217,11 +217,24 @@ function our_serialize_json(io::IO, dict::Union{VersionsJsonDocument, InternalJs
 end
 
 function checkpoint(content::OutputJsonContent, cfg::Config)
-    open(cfg.versions_json_filename, "w") do io
-        our_serialize_json(io, content.versions_json)
-    end
-    open(cfg.internal_json_filename, "w") do io
-        our_serialize_json(io, content.internal_json)
+    mktempdir() do tmpdir
+        version_json_tempfile = joinpath(tmpdir, "version.json.temp")
+        internal_json_tempfile = joinpath(tmpdir, "internal.json.temp")
+
+        version_json_truefile = cfg.versions_json_filename
+        internal_json_truefile = cfg.internal_json_filename
+
+        open(version_json_tempfile, "w") do io
+            our_serialize_json(io, content.versions_json)
+        end
+        open(internal_json_tempfile, "w") do io
+            our_serialize_json(io, content.internal_json)
+        end
+
+        # We don't move to the true location until we've completely finished serializing.
+        # That way, if an error is thrown during serialization, we don't have a broken JSON file.
+        mv(version_json_tempfile, version_json_truefile; force = true)
+        mv(internal_json_tempfile, internal_json_truefile; force = true)
     end
     return nothing
 end
@@ -468,8 +481,11 @@ function main!(content::OutputJsonContent, cfg::Config)
         return nothing
     end
 
-    checkpoint(content, cfg)
     for version in tag_versions
+        # Write out new versions of our versions.json every time we finish a version.
+        # The fact that we wait until we've finished a version is intentional.
+        # We don't want to write out a partial version - we want to wait until we've finished the version.
+        checkpoint(content, cfg)
         for platform in julia_platforms
             url_probe_index += 1
             url = download_url(version, platform)
@@ -495,7 +511,6 @@ function main!(content::OutputJsonContent, cfg::Config)
                 catch ex
                     if (ex isa HTTP.Exceptions.StatusError) && (ex.status == 404)
                         mark_url_as_nonexistent!(content, version, url)
-                        checkpoint(content, cfg)
                         update_download_progress!(version, filename; advance = true)
                         continue # skip the rest of this for-loop iteration
                     else
@@ -561,8 +576,7 @@ function main!(content::OutputJsonContent, cfg::Config)
                 # and make this an array of dictionaries that is easy to extensibly match
                 push!(meta[version].files, FileDict(file_dict))
 
-                # Write out new versions of our versions.json as we go
-                checkpoint(content, cfg)
+
 
                 # Delete downloaded file
                 rm(filepath)
@@ -589,7 +603,6 @@ function main!(content::OutputJsonContent, cfg::Config)
                     catch ex
                         if (ex isa HTTP.Exceptions.StatusError) && (ex.status == 404)
                             mark_url_as_nonexistent!(content, version, url)
-                            checkpoint(content, cfg)
                             update_download_progress!(version, filename; advance = true)
                             continue # skip the rest of this for-loop iteration
                         else
@@ -601,7 +614,6 @@ function main!(content::OutputJsonContent, cfg::Config)
                 # Add in `.asc` signature content, if applicable
                 if !isnothing(asc_signature)
                     file_dict.asc = asc_signature
-                    checkpoint(content, cfg)
                 end
             end
             update_download_progress!(version, filename; advance = true)