perlsky is a Perl 5 implementation of an AT Protocol Personal Data Server.
Stop gzipping sync blob downloads
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docs/DEPLOYMENT.md
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docs/DEPLOYMENT.md
···
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}
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```
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`com.atproto.sync.getBlob` responses should stay uncompressed end-to-end. `perlsky` now bypasses Mojolicious dynamic gzip for blob bytes because some downstream image proxy routes will auto-decompress the body and accidentally forward a stale `Content-Encoding` header, which shows up in clients as broken image loads (`ERR_CONTENT_DECODING_FAILED`).
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This still requires wildcard DNS or per-handle DNS records so public ACME validation can reach the server.
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A minimal nginx site looks like:
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lib/ATProto/PDS/API/Sync.pm
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lib/ATProto/PDS/API/Sync.pm
···
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$c->res->headers->header('Content-Disposition' => 'attachment; filename="' . ($c->param('cid') // q()) . '"');
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$c->res->headers->header('Content-Security-Policy' => q{default-src 'none'; sandbox});
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$c->observe_blob_egress($blob->{mime_type}, length($bytes));
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-
$c->render(data => $bytes);
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# Blob bytes need to bypass Mojolicious' dynamic gzip so image proxy routes
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# do not see a decompressed body paired with a stale Content-Encoding header.
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$c->res->body($bytes);
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$c->rendered(200);
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return;
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});
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+10
t/blob-sync-surfaces.t
+10
t/blob-sync-surfaces.t
···
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->status_is(200);
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is($t->tx->res->body, 'blob-bytes', 'blob bytes are served back');
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like($t->tx->res->headers->content_type // '', qr{image/png}, 'blob content type preserved');
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ok(!defined($t->tx->res->headers->content_encoding), 'blob download is not dynamically compressed by default');
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my $gzip_blob_tx = $t->ua->build_tx(
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GET => '/xrpc/com.atproto.sync.getBlob?did=' . $did . '&cid=' . $blob_cid => {
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'Accept-Encoding' => 'gzip',
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},
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);
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$t->request_ok($gzip_blob_tx)->status_is(200);
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is($t->tx->res->body, 'blob-bytes', 'blob bytes stay readable when gzip is accepted');
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ok(!defined($t->tx->res->headers->content_encoding), 'blob download ignores Accept-Encoding gzip');
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$t->get_ok('/xrpc/com.atproto.sync.getLatestCommit?did=' . $did)
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->status_is(200)