huayra / varnish3to4

Varnish 3 to 4 migration script

varnish3to4


Script to assist migrating a VCL file from Varnish 3 to 4.x.

Suggested usage

 $ varnish3to4 -o <filename>.v4 <filename>
 $ diff -u <filename> <filename>.v4

To include changes for Varnish 4.1:

 $ varnish3to4 --41 -o <filename>.v4 <filename>
 $ diff -u <filename> <filename>.v4

Currently understands

V3	V4
{bereq,req}.backend.healthy	std.healthy({bereq.backend,req.backend_hint})
{bereq,req}.request	{bereq,req}.method
bereq.* in vcl_pass and vcl_miss	req.*
{beresp,obj,resp}.response	{beresp,obj,resp}.reason
beresp.storage	beresp.storage_hint
{client,server}.port	std.port({client,server}.ip)
error code response	return (synth(code, response))
obj.hits - writing to	-
obj.* in vcl_synth	resp.*
obj.lastuse	-
remove	unset
req.backend	req.backend_hint
req.grace	-
req.* in vcl_backend_response	bereq.*
return (fetch) in vcl_hit [1][2]	return (miss)
return (hash) in vcl_hash	return (lookup)
return (hit_for_pass)	set beresp.uncacheable = true; return (deliver);
return (lookup) in vcl_recv	return (hash)
return (pass) in vcl_pass	return (fetch)
return (restart) in vcl_fetch	return (retry)
std.real2integer(..) [1]	std.real2integer(.., n)
std.time2integer(..) [1]	std.time2integer(.., n)
std.time2real(..) [1]	std.time2real(.., n.n)
synthetic ..	synthetic(..)
vcl_error	vcl_backend_error and vcl_synth
vcl_fetch	vcl_backend_response

Limited coverage

V3	V4
purge	-

Won't be implemented

V3	V4

• | vcl 4.0
• | import directors
  new xx = directors.yy();
  xx.add_backend(ss);
  set req.backend_hint = xx.backend();

Add imports resulting from changes in V4, complete purge handling and any other changes missing from this document.

1. Varnish 4.1 and above.
2. This change is optional in 4.1 but mandatory starting with 5.0.