first commit

grafana/dashboards/requests/node_modules/http-basic/lib/cache-control-utils.js

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+"use strict";
+exports.__esModule = true;
+var parseCacheControl = require('parse-cache-control');
+function parseCacheControlHeader(res) {
+    var cacheControl = res.headers['cache-control'];
+    var normalisedCacheControl = typeof cacheControl === 'string' ? cacheControl.trim() : ''; // must be normalised for parsing (e.g. parseCacheControl)
+    if (!cacheControl) {
+        return null;
+    }
+    return parseCacheControl(cacheControl);
+}
+// for the purposes of this library, we err on the side of caution and do not cache anything except public (or implicit public)
+var nonCaching = ['private', 'no-cache', 'no-store', 'no-transform', 'must-revalidate', 'proxy-revalidate'];
+function isCacheControlCacheable(parsedCacheControl) {
+    if (!parsedCacheControl) {
+        return false;
+    }
+    if (parsedCacheControl.public) {
+        return true;
+    }
+    // note that the library does not currently support s-maxage
+    if (parsedCacheControl["max-age"]) {
+        // https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9.3
+        // The max-age directive on a response implies that the response is cacheable (i.e., "public") unless some other, more restrictive cache directive is also present.
+        for (var i = 0; i < nonCaching.length; i++) {
+            if (parsedCacheControl[nonCaching[i]]) {
+                return false;
+            }
+        }
+        return true;
+    }
+    return false;
+}
+/**
+ * returns true if this response is cacheable (according to cache-control headers)
+ */
+function isCacheable(res) {
+    return isCacheControlCacheable(parseCacheControlHeader(res));
+}
+exports.isCacheable = isCacheable;
+function buildPolicy(parsedCacheControl) {
+    // note that the library does not currently support s-maxage
+    return { maxage: parsedCacheControl['max-age'] || null };
+}
+/**
+ * if the response is cacheable, returns an object detailing the maxage of the cache
+ * otherwise returns null
+ */
+function cachePolicy(res) {
+    var parsed = parseCacheControlHeader(res);
+    return parsed && isCacheControlCacheable(parsed) ? buildPolicy(parsed) : null;
+}
+exports.cachePolicy = cachePolicy;