Gzip¶
By enabling compression in Envoy you can save some network bandwidth, at the expense of increased processor usage.
Envoy supports compression and decompression for both requests and responses.
This sandbox provides an example of response compression served over HTTP
. Although HTTPS
is not demonstrated, compression can be used for this also.
The sandbox covers two scenarios:
compression of files from an upstream server
compression of Envoy’s own statistics
Step 1: Start all of our containers¶
Change to the examples/gzip
directory and bring up the docker composition.
$ pwd
envoy/examples/gzip
$ docker-compose build --pull
$ docker-compose up -d
$ docker-compose ps
Name Command State Ports
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
gzip_envoy-stats_1 /docker-entrypoint.sh /usr ... Up 0.0.0.0:10000->10000/tcp,:::10000->10000/tcp, 0.0.0.0:9901->9901/tcp,:::9901->9901/tcp, 0.0.0.0:9902->9902/tcp,:::9902->9902/tcp
gzip_service_1 python3 /code/service.py Up
Step 2: Test Envoy’s compression of upstream files¶
The sandbox is configured with two endpoints on port 10000
for serving upstream files:
/file.txt
/file.json
Only /file.json
is configured to be compressed.
Use curl
to check that the response from requesting file.json
contains the content-encoding: gzip
header.
You will need to add an accept-encoding: gzip
request header.
$ curl -si -H "Accept-Encoding: gzip" localhost:10000/file.json | grep "content-encoding"
content-encoding: gzip
As only files with a content-type of application/json
are configured to be gzipped, the response from requesting file.txt
should not contain the content-encoding: gzip
header, and the file will not be compressed:
$ curl -si -H "Accept-Encoding: gzip" localhost:10000/file.txt | grep "content-encoding"
Step 3: Test compression of Envoy’s statistics¶
The sandbox is configured with two ports serving Envoy’s admin and statistics interface:
9901
exposes the standard admin interface9902
exposes a compressed version of the admin interface
Use curl
to make a request for uncompressed statistics on port 9901
, it should not contain the content-encoding
header in the response:
$ curl -si -H "Accept-Encoding: gzip" localhost:9901/stats/prometheus | grep "content-encoding"
Now, use curl
to make a request for the compressed statistics:
$ curl -si -H "Accept-Encoding: gzip" localhost:9902/stats/prometheus | grep "content-encoding"
content-encoding: gzip
See also
- Gzip API
API and configuration reference for Envoy’s gzip compression.
- Compression configuration
Reference documentation for Envoy’s compressor filter.
- Envoy admin quick start guide
Quick start guide to the Envoy admin interface.