Add PROXY_CACHE_USE_STALE environment variable

default value for this variable is 'error timeout http_500 http_502 http_503 http_504'.

Author: MohammadHosein Bahmani

Dockerfile.buildkit.plus

@@ -16,6 +16,7 @@ ENV PROXY_CACHE_SLICE_SIZE=1m
 ENV PROXY_CACHE_VALID_OK=1h
 ENV PROXY_CACHE_VALID_NOTFOUND=1m
 ENV PROXY_CACHE_VALID_FORBIDDEN=30s
+ENV PROXY_CACHE_USE_STALE='error timeout http_500 http_502 http_503 http_504'
 
 # CORS env vars
 ENV CORS_ENABLED=0

Dockerfile.oss

@@ -11,6 +11,7 @@ ENV PROXY_CACHE_SLICE_SIZE=1m
 ENV PROXY_CACHE_VALID_OK=1h
 ENV PROXY_CACHE_VALID_NOTFOUND=1m
 ENV PROXY_CACHE_VALID_FORBIDDEN=30s
+ENV PROXY_CACHE_USE_STALE='error timeout http_500 http_502 http_503 http_504'
 
 # CORS env vars
 ENV CORS_ENABLED=0

Dockerfile.plus

@@ -16,6 +16,7 @@ ENV PROXY_CACHE_SLICE_SIZE=1m
 ENV PROXY_CACHE_VALID_OK=1h
 ENV PROXY_CACHE_VALID_NOTFOUND=1m
 ENV PROXY_CACHE_VALID_FORBIDDEN=30s
+ENV PROXY_CACHE_USE_STALE='error timeout http_500 http_502 http_503 http_504'
 
 # CORS env vars
 ENV CORS_ENABLED=0