Zlib::BufError: buffer error

[mattandayo]

Basic Info

• Faraday Version: 0.12.2
• Ruby Version: 2.5.3

Issue description

I have a rails app with requesting a api by http.
See example below:

conn = Faraday::Connection.new(
           url: 'API base url',
           headers: {
             'apikey': 'API Key',
             'content-type': 'application/json'
           }
         )

res = conn.post do |req|
  req.url '/end_point'
  req.body = 'json'
end

I succeeded the way that is requesting with the same content by curl, but I didn't succeeded the way with using faraday.
client.post raised Zlib::BufError .
See example below:

res = conn.post do |req|
  req.url 'end_point'
  req.body = 'json'
end

=>
Zlib::BufError: buffer error
from /usr/local/lib/ruby/2.5.3/net/http/response.rb:366:in `finish'

Is there any settings in Faraday that I'm missing ?
Any help would be greatly appreciated. Thanks

[iMacTia]

@mattandayo since the last stack trace call is on Net::HTTP, I'd first like to confirm this is a Faraday issue. Have you tried performing the same request using pure Net::HTTP Ruby client?

[technoweenie]

A Zlib error implies issues regarding gzip encoding. Net::HTTP sends an Accept-Encoding header to enable compression automatically.

Some questions:

1. What HTTP headers from the request is the Rails app seeing? It should require an Accept-Encoding header specifying gzip or deflate before it compresses the response body.
2. What HTTP headers is the Rails app sending? If it's gzipping the response, there should be a Content-Encoding header saying that.

Since Faraday is raising an exception, it may not be that useful in debugging this. A full curl -v ... command for the exact same request could help.

There's the possibility that the Zlib error is raised because irb is calling Faraday::Response#inspect. You can get around that like this:

require 'pp'
res = conn.post do |req|
  req.url 'end_point'
  req.body = 'json'
end ; nil # this prevents irb from calling res.inspect
pp res.headers

[grosser]

at least faraday should catch this error and re-raise as Faradayish error ?

just saw the same while doing a http get:

Zlib::BufError: buffer error
  File "/usr/local/lib/ruby/2.6.0/net/http/response.rb", line 366, in finish
  File "/usr/local/lib/ruby/2.6.0/net/http/response.rb", line 366, in finish
  File "/usr/local/lib/ruby/2.6.0/net/http/response.rb", line 268, in ensure in inflater
  File "/usr/local/lib/ruby/2.6.0/net/http/response.rb", line 267, in inflater
  File "/usr/local/lib/ruby/2.6.0/net/http/response.rb", line 283, in read_body_0
  File "/usr/local/lib/ruby/2.6.0/net/http/response.rb", line 204, in read_body
  File "/usr/local/lib/ruby/2.6.0/net/http.rb", line 1229, in block in get
  File "/usr/local/lib/ruby/2.6.0/net/http.rb", line 1518, in block in transport_request
  File "/usr/local/lib/ruby/2.6.0/net/http/response.rb", line 165, in reading_body
  File "/usr/local/lib/ruby/2.6.0/net/http.rb", line 1517, in transport_request
  File "/usr/local/lib/ruby/2.6.0/net/http.rb", line 1479, in request
  File "/usr/local/lib/ruby/2.6.0/net/http.rb", line 1472, in block in request
  File "/usr/local/lib/ruby/2.6.0/net/http.rb", line 920, in start
  File "/usr/local/lib/ruby/2.6.0/net/http.rb", line 1470, in request
  File "/usr/local/lib/ruby/2.6.0/net/http.rb", line 1228, in get
  File "/app/vendor/bundle/ruby/2.6.0/gems/faraday-0.15.0/lib/faraday/adapter/net_http.rb", line 80, in perform_request