Add configuration parameter to disable caching (ignore If-Modified-Si…

…nce header)
eeditiones · May 23, 2022 · 82a7a63 · 82a7a63
1 parent 48b65f2
commit 82a7a63
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Showing 4 changed files with 65 additions and 36 deletions.
diff --git a/Dockerfile b/Dockerfile
@@ -89,6 +89,7 @@ ARG HTTPS_PORT=8443
 
 ENV NER_ENDPOINT=http://localhost:8001
 ENV CONTEXT_PATH=auto
+ENV PROXY_CACHING=false
 
 ENV JAVA_OPTS \
     -Djetty.port=${HTTP_PORT} \
@@ -108,4 +109,4 @@ RUN if [ "${ADMIN_PASS}" != "none" ]; then bin/client.sh -l --no-gui --xpath "sm
 
 EXPOSE ${HTTP_PORT}
 
-ENTRYPOINT JAVA_OPTS="${JAVA_OPTS} -Dteipublisher.ner-endpoint=${NER_ENDPOINT} -Dteipublisher.context-path=${CONTEXT_PATH}" /exist/bin/startup.sh
+ENTRYPOINT JAVA_OPTS="${JAVA_OPTS} -Dteipublisher.ner-endpoint=${NER_ENDPOINT} -Dteipublisher.context-path=${CONTEXT_PATH} -Dteipublisher.proxy-caching=${PROXY_CACHING}" /exist/bin/startup.sh
diff --git a/modules/config.xqm b/modules/config.xqm
@@ -29,7 +29,19 @@ declare variable $config:origin-whitelist := (
     "https?://teipublisher.onrender.com"
 );
 
-(:~~
+(:~
+ : Set to true to allow caching: if the browser sends an If-Modified-Since header,
+ : TEI Publisher will respond with a 304 if the resource has not changed since last
+ : access. However, this does *not* take into account changes to ODD or other auxiliary 
+ : files, so don't use it during development.
+ :)
+declare variable $config:enable-proxy-caching :=
+    let $prop := util:system-property("teipublisher.proxy-caching")
+    return
+        exists($prop) and lower-case($prop) = 'true'
+;
+
+(:~
  : The version of the pb-components webcomponents library to be used by this app.
  : Should either point to a version published on npm,
  : or be set to 'local' or 'dev'. 

diff --git a/modules/lib/api/caching.xql b/modules/lib/api/caching.xql
@@ -3,42 +3,46 @@ xquery version "3.1";
 module namespace cutil="http://teipublisher.com/api/cache";
 
 import module namespace router="http://exist-db.org/xquery/router";
+import module namespace config="http://www.tei-c.org/tei-simple/config" at "../../config.xqm";
 
 declare function cutil:check-last-modified($request as map(*), $nodes as node()*, $callback as function(*)) {
-    util:log('INFO', 'If-Modified-Since: ' || $request?parameters?If-Modified-Since),
-    let $ifModifiedSince :=
-        if (map:contains($request?parameters, 'If-Modified-Since')) then
-            $request?parameters?If-Modified-Since => parse-ietf-date()
-        else
-            ()
-    let $lastModified :=
-        for $node in $nodes
-        let $modified :=
-            xmldb:last-modified(util:collection-name($node), util:document-name($node))
-        order by $modified descending
-        return
-            $modified
-    let $shouldReturn304 :=
-        if (exists($ifModifiedSince)) then
-            $ifModifiedSince ge
-                $lastModified
-                (: For the purpose of comparing the resource's last modified date with the If-Modified-Since
-                 : header supplied by the client, we must truncate any milliseconds from the last modified date.
-                 : This is because HTTP-date is only specific to the second.
-                 : @see https://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.3.1 :)
-                => format-dateTime("[Y0001]-[M01]-[D01]T[H01]:[m01]:[s01][Z]")
-                => xs:dateTime()
-        else
-            ()
-    return (
-        if(string-length($lastModified) >0) 
-        then (response:set-header("Last-Modified", cutil:format-http-date(head($lastModified)))) 
-        else (),        
-        if ($shouldReturn304) then
-            router:response(304, "", "")
-        else
-            $callback($request, $nodes)
-    )
+    if ($config:enable-proxy-caching) then (
+        util:log('INFO', 'If-Modified-Since: ' || $request?parameters?If-Modified-Since),
+        let $ifModifiedSince :=
+            if (map:contains($request?parameters, 'If-Modified-Since')) then
+                $request?parameters?If-Modified-Since => parse-ietf-date()
+            else
+                ()
+        let $lastModified :=
+            for $node in $nodes
+            let $modified :=
+                xmldb:last-modified(util:collection-name($node), util:document-name($node))
+            order by $modified descending
+            return
+                $modified
+        let $shouldReturn304 :=
+            if (exists($ifModifiedSince)) then
+                $ifModifiedSince ge
+                    $lastModified
+                    (: For the purpose of comparing the resource's last modified date with the If-Modified-Since
+                    : header supplied by the client, we must truncate any milliseconds from the last modified date.
+                    : This is because HTTP-date is only specific to the second.
+                    : @see https://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.3.1 :)
+                    => format-dateTime("[Y0001]-[M01]-[D01]T[H01]:[m01]:[s01][Z]")
+                    => xs:dateTime()
+            else
+                ()
+        return (
+            if(string-length($lastModified) >0) 
+            then (response:set-header("Last-Modified", cutil:format-http-date(head($lastModified)))) 
+            else (),        
+            if ($shouldReturn304) then
+                router:response(304, "", "")
+            else
+                $callback($request, $nodes)
+        )
+    ) else
+        $callback($request, $nodes)
 };
 
 declare function cutil:format-http-date($dateTime as xs:dateTime) as xs:string {

diff --git a/templates/basic/modules/config.xqm b/templates/basic/modules/config.xqm
@@ -52,6 +52,18 @@ declare variable $config:origin-whitelist := (
     "(?:https?://localhost:.*|https?://127.0.0.1:.*)"
 );
 
+(:~
+ : Set to true to allow caching: if the browser sends an If-Modified-Since header,
+ : TEI Publisher will respond with a 304 if the resource has not changed since last
+ : access. However, this does *not* take into account changes to ODD or other auxiliary 
+ : files, so don't use it during development.
+ :)
+declare variable $config:enable-proxy-caching :=
+    let $prop := util:system-property("teipublisher.proxy-caching")
+    return
+        exists($prop) and lower-case($prop) = 'true'
+;
+
 (:~
  : Should documents be located by xml:id or filename?
  :)