luci-base: fs.js: add read_direct() and exec_direct() functions

Signed-off-by: Jo-Philipp Wich <jo@mein.io>
(cherry picked from commit f3724e46a5fc33b3a6fc9f935b88e395c746149f)

diff --git a/modules/luci-base/htdocs/luci-static/resources/fs.js b/modules/luci-base/htdocs/luci-static/resources/fs.js
index 8a96ea87e2e88294950f451cd5fa244e2a378992..612d4eb0f58545de135a7bbfc15ab920d4cac364 100644 (file)
--- a/modules/luci-base/htdocs/luci-static/resources/fs.js
+++ b/modules/luci-base/htdocs/luci-static/resources/fs.js
@@ -108,6 +108,31 @@ function handleRpcReply(expect, rc) {
        return rc;
 }
 
+function handleCgiIoReply(res) {
+       if (!res.ok || res.status != 200) {
+               var e = new Error(res.statusText);
+               switch (res.status) {
+               case 400:
+                       e.name = 'InvalidArgumentError';
+                       break;
+
+               case 403:
+                       e.name = 'PermissionError';
+                       break;
+
+               case 404:
+                       e.name = 'NotFoundError';
+                       break;
+
+               default:
+                       e.name = 'Error';
+               }
+               throw e;
+       }
+
+       return res.text();
+}
+
 /**
  * @class fs
  * @memberof LuCI
@@ -293,6 +318,74 @@ var FileSystem = L.Class.extend(/** @lends LuCI.fs.prototype */ {
 
                        return lines;
                });
+       },
+
+       /**
+        * Read the contents of the given file and return them, bypassing ubus.
+        *
+        * This function will read the requested file through the cgi-io
+        * helper applet at `/cgi-bin/cgi-download` which bypasses the ubus rpc
+        * transport. This is useful to fetch large file contents which might
+        * exceed the ubus message size limits or which contain binary data.
+        *
+        * The cgi-io helper will enforce the same access permission rules as
+        * the ubus based read call.
+        *
+        * @param {string} path
+        * The file path to read.
+        *
+        * @returns {Promise<string>}
+        * Returns a promise resolving to a string containing the file contents or
+        * rejecting with an error stating the failure reason.
+        */
+       read_direct: function(path) {
+               var postdata = 'sessionid=%s&path=%s'
+                       .format(encodeURIComponent(L.env.sessionid), encodeURIComponent(path));
+
+               return L.Request.post('/cgi-bin/cgi-download', postdata, {
+                       headers: { 'Content-Type': 'application/x-www-form-urlencoded' }
+               }).then(handleCgiIoReply);
+       },
+
+       /**
+        * Execute the specified command, bypassing ubus.
+        *
+        * Note: The `command` must be either the path to an executable,
+        * or a basename without arguments in which case it will be searched
+        * in $PATH. If specified, the values given in `params` will be passed
+        * as arguments to the command.
+        *
+        * This function will invoke the requested commands through the cgi-io
+        * helper applet at `/cgi-bin/cgi-exec` which bypasses the ubus rpc
+        * transport. This is useful to fetch large command outputs which might
+        * exceed the ubus message size limits or which contain binary data.
+        *
+        * The cgi-io helper will enforce the same access permission rules as
+        * the ubus based exec call.
+        *
+        * @param {string} command
+        * The command to invoke.
+        *
+        * @param {string[]} [params]
+        * The arguments to pass to the command.
+        *
+        * @returns {Promise<string>}
+        * Returns a promise resolving to the gathered command stdout output or
+        * rejecting with an error stating the failure reason.
+        */
+       exec_direct: function(command, params) {
+               var cmdstr = command;
+
+               if (Array.isArray(params))
+                       for (var i = 0; i < params.length; i++)
+                               cmdstr += ' ' + params[i];
+
+               var postdata = 'sessionid=%s&command=%s'
+                       .format(encodeURIComponent(L.env.sessionid), encodeURIComponent(cmdstr));
+
+               return L.Request.post('/cgi-bin/cgi-exec', postdata, {
+                       headers: { 'Content-Type': 'application/x-www-form-urlencoded' }
+               }).then(handleCgiIoReply);
        }
 });