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releases/0.4.2.md

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+# pict-rs 0.4.2
+
+## Overview
+
+I'm happy to announc pict-rs 0.4.2 today. This is a smaller release but includes some important
+changes. A few users had been seeing issues around pict-rs' HTTP client when talking to object
+storage or downloading media, this release should fix these issues.
+
+### Features
+
+- [Process Timeout](#process-timeout)
+
+
+### Bugfix
+
+- [Dangling Backgrounded Uploads](#dangling-backgrounded-uploads)
+
+
+### Changes
+
+- [Reqwest](#reqwest)
+
+
+## Upgrade Notes
+
+There's no significant changes from 0.4.1, so upgrading should be as simple as pulling a new version
+of pict-rs.
+
+
+## Descriptions
+
+### Process Timeout
+
+pict-rs spawns processes to handle identifying and processing images. These processes have not had
+many bounds in place so far, and are left to run more or less unattended for as long as they care to
+take. This can cause problems when a large file is uploaded and causes clients to time out while
+waiting. While the proper solution for these cases is to use the backgrounded endpoint to avoid
+timing out http requests when processing large files, It may be worth limiting the duration these
+processes are allowed to run for.
+
+0.4.2 introduces a new config option: `PICTRS__MEDIA__PROCESS_TIMEOUT`, which governs how long any
+given process that pict-rs spawns is allowed to run. The default value here is 30 seconds, but on
+systems with slower CPUs or if larger files need to be handled, this value can be increased.
+Alternatively, if only small or simple files need to be hosted, then this value can be lowered,
+ensuring any file that is too complex will not be succesfully processed.
+
+When an operation times out, this is considered a client error, since the client initiated a request
+with a file too complex to process in a reasonable amount of time.
+
+
+### Dangling Backgrounded Uploads
+
+In some cases, a backgrounded upload could fail and leave the original unprocessed media in the
+store, but inaccessible from any client. This is now solved by ensuring that even when processing a
+backgrounded upload fails, the source files are cleaned before the job completes.
+
+
+### Reqwest
+
+This release swaps the `awc` HTTP client library for `reqwest`. Due to a number of HTTP-related
+issues, and awc's status as a less-supported member of the actix-web ecosystem, pict-rs has moved to
+`reqwest` for making HTTP requests. This should result in slightly better performance, fewer
+dangling connections, and fewer connection errors.
+
+The `PICTRS__SERVER__CLIENT_POOL_SIZE` variable is now less useful. Since reqwest doesn't give
+control of its pool size directly, this value now limits simultaneous idle connections to a given
+host.