🔧 allow gzip to be set via env (#1133)

* 🔧 allow gzip to be set via env

* 📝 update changelog

Author: chriddyp

CHANGELOG.md

@@ -2,6 +2,10 @@
 All notable changes to `dash` will be documented in this file.
 This project adheres to [Semantic Versioning](http://semver.org/).
 
+## [Unreleased]
+### Added
+- [#1133](github.com/plotly/dash/pull/1133) Allow the `compress` config variable to be set with an environment variable with DASH_COMPRESS=FALSE
+
 ## [1.9.0] - 2020-02-04
 ### Fixed
 - [#1080](https://github.com/plotly/dash/pull/1080) Handle case where dash fails to load when used inside an iframe with a sandbox attribute that only has allow-scripts

dash/_configs.py

@@ -29,12 +29,13 @@ def load_dash_env_vars():
                 'DASH_HOT_RELOAD_MAX_RETRY',
                 'DASH_SILENCE_ROUTES_LOGGING',
                 'DASH_PRUNE_ERRORS',
+                'DASH_COMPRESS'
             )
         }
     )
 
 
-DASH_ENV_VARS = load_dash_env_vars()
+DASH_ENV_VARS = load_dash_env_vars()  # used in tests
 
 
 def get_combined_config(name, val, default=None):

dash/dash.py

@@ -221,7 +221,7 @@ def __init__(
         requests_pathname_prefix=None,
         routes_pathname_prefix=None,
         serve_locally=True,
-        compress=True,
+        compress=None,
         meta_tags=None,
         index_string=_default_index,
         external_scripts=None,
@@ -276,7 +276,9 @@ def __init__(
             routes_pathname_prefix=routes_prefix,
             requests_pathname_prefix=requests_prefix,
             serve_locally=serve_locally,
-            compress=compress,
+            compress=get_combined_config(
+                "compress", compress, True
+            ),
             meta_tags=meta_tags or [],
             external_scripts=external_scripts or [],
             external_stylesheets=external_stylesheets or [],