'use strict';
'require baseclass';
'require request';
let rpcRequestID = 1;
let rpcSessionID = L.env.sessionid ?? '00000000000000000000000000000000';
let rpcBaseURL = L.url('admin/ubus');
const rpcInterceptorFns = [];
/**
* @class rpc
* @memberof LuCI
* @hideconstructor
* @classdesc
*
* The `LuCI.rpc` class provides high level ubus JSON-RPC abstractions
* and means for listing and invoking remove RPC methods.
*/
return baseclass.extend(/** @lends LuCI.rpc.prototype */ {
/* privates */
call(req, cb, nobatch) {
let q = '';
if (Array.isArray(req)) {
if (req.length == 0)
return Promise.resolve([]);
for (let i = 0; i < req.length; i++)
if (req[i].params)
q += '%s%s.%s'.format(
q ? ';' : '/',
req[i].params[1],
req[i].params[2]
);
}
return request.post(rpcBaseURL + q, req, {
timeout: (L.env.rpctimeout ?? 20) * 1000,
nobatch,
credentials: true
}).then(cb, cb);
},
parseCallReply(req, res) {
let msg = null;
if (res instanceof Error)
return req.reject(res);
try {
if (!res.ok)
L.raise('RPCError', 'RPC call to %s/%s failed with HTTP error %d: %s',
req.object, req.method, res.status, res.statusText || '?');
msg = res.json();
}
catch (e) {
return req.reject(e);
}
/*
* The interceptor args are intentionally swapped.
* Response is passed as first arg to align with Request class interceptors
*/
Promise.all(rpcInterceptorFns.map(fn => fn(msg, req)))
.then(this.handleCallReply.bind(this, req, msg))
.catch(req.reject);
},
handleCallReply(req, msg) {
const type = Object.prototype.toString;
let ret = null;
try {
/* verify message frame */
if (!L.isObject(msg) || msg.jsonrpc != '2.0')
L.raise('RPCError', 'RPC call to %s/%s returned invalid message frame',
req.object, req.method);
/* check error condition */
if (L.isObject(msg.error) && msg.error.code && msg.error.message)
L.raise('RPCError', 'RPC call to %s/%s failed with error %d: %s',
req.object, req.method, msg.error.code, msg.error.message || '?');
}
catch (e) {
return req.reject(e);
}
if (!req.object && !req.method) {
ret = msg.result;
}
else if (Array.isArray(msg.result)) {
if (req.raise && msg.result[0] !== 0)
L.raise('RPCError', 'RPC call to %s/%s failed with ubus code %d: %s',
req.object, req.method, msg.result[0], this.getStatusText(msg.result[0]));
ret = (msg.result.length > 1) ? msg.result[1] : msg.result[0];
}
if (req.expect) {
for (const key in req.expect) {
if (ret != null && key != '')
ret = ret[key];
if (ret == null || type.call(ret) != type.call(req.expect[key]))
ret = req.expect[key];
break;
}
}
/* apply filter */
if (typeof(req.filter) == 'function') {
req.priv[0] = ret;
req.priv[1] = req.params;
ret = req.filter.apply(this, req.priv);
}
req.resolve(ret);
},
/**
* Lists available remote ubus objects or the method signatures of
* specific objects.
*
* This function has two signatures and is sensitive to the number of
* arguments passed to it:
* - `list()` -
* Returns an array containing the names of all remote `ubus` objects
* - `list("objname", ...)`
* Returns method signatures for each given `ubus` object name.
*
* @param {...string} [objectNames]
* If any object names are given, this function will return the method
* signatures of each given object.
*
* @returns {Promise<Array<string>|Object<string, Object<string, Object<string, string>>>>}
* When invoked without arguments, this function will return a promise
* resolving to an array of `ubus` object names. When invoked with one or
* more arguments, a promise resolving to an object describing the method
* signatures of each requested `ubus` object name will be returned.
*/
list(...args) {
const msg = {
jsonrpc: '2.0',
id: rpcRequestID++,
method: 'list',
params: args.length ? args : undefined
};
return new Promise(L.bind(function(resolve, reject) {
/* store request info */
const req = { resolve, reject };
/* call rpc */
this.call(msg, this.parseCallReply.bind(this, req));
}, this));
},
/**
* @typedef {Object} DeclareOptions
* @memberof LuCI.rpc
*
* @property {string} object
* The name of the remote `ubus` object to invoke.
*
* @property {string} method
* The name of the remote `ubus` method to invoke.
*
* @property {string[]} [params]
* Lists the named parameters expected by the remote `ubus` RPC method.
* The arguments passed to the resulting generated method call function
* will be mapped to named parameters in the order they appear in this
* array.
*
* Extraneous parameters passed to the generated function will not be
* sent to the remote procedure but are passed to the
* {@link LuCI.rpc~filterFn filter function} if one is specified.
*
* Examples:
* - `params: [ "foo", "bar" ]` -
* When the resulting call function is invoked with `fn(true, false)`,
* the corresponding args object sent to the remote procedure will be
* `{ foo: true, bar: false }`.
* - `params: [ "test" ], filter: function(reply, args, extra) { ... }` -
* When the resulting generated function is invoked with
* `fn("foo", "bar", "baz")` then `{ "test": "foo" }` will be sent as
* argument to the remote procedure and the filter function will be
* invoked with `filterFn(reply, [ "foo" ], "bar", "baz")`
*
* @property {Object<string,*>} [expect]
* Describes the expected return data structure. The given object is
* supposed to contain a single key selecting the value to use from
* the returned `ubus` reply object. The value of the sole key within
* the `expect` object is used to infer the expected type of the received
* `ubus` reply data.
*
* If the received data does not contain `expect`'s key, or if the
* type of the data differs from the type of the value in the expect
* object, the expect object's value is returned as default instead.
*
* The key in the `expect` object may be an empty string (`''`) in which
* case the entire reply object is selected instead of one of its subkeys.
*
* If the `expect` option is omitted, the received reply will be returned
* as-is, regardless of its format or type.
*
* Examples:
* - `expect: { '': { error: 'Invalid response' } }` -
* This requires the entire `ubus` reply to be a plain JavaScript
* object. If the reply isn't an object but e.g. an array or a numeric
* error code instead, it will get replaced with
* `{ error: 'Invalid response' }` instead.
* - `expect: { results: [] }` -
* This requires the received `ubus` reply to be an object containing
* a key `results` with an array as value. If the received reply does
* not contain such a key, or if `reply.results` points to a non-array
* value, the empty array (`[]`) will be used instead.
* - `expect: { success: false }` -
* This requires the received `ubus` reply to be an object containing
* a key `success` with a boolean value. If the reply does not contain
* `success` or if `reply.success` is not a boolean value, `false` will
* be returned as default instead.
*
* @property {LuCI.rpc~filterFn} [filter]
* Specifies an optional filter function which is invoked to transform the
* received reply data before it is returned to the caller.
*
* @property {boolean} [reject=false]
* If set to `true`, non-zero ubus call status codes are treated as fatal
* error and lead to the rejection of the call promise. The default
* behaviour is to resolve with the call return code value instead.
*/
/**
* The filter function is invoked to transform a received `ubus` RPC call
* reply before returning it to the caller.
*
* @callback LuCI.rpc~filterFn
*
* @param {*} data
* The received `ubus` reply data or a subset of it as described in the
* `expect` option of the RPC call declaration. In case of remote call
* errors, `data` is numeric `ubus` error code instead.
*
* @param {Array<*>} args
* The arguments the RPC method has been invoked with.
*
* @param {...*} extraArgs
* All extraneous arguments passed to the RPC method exceeding the number
* of arguments describes in the RPC call declaration.
*
* @return {*}
* The return value of the filter function will be returned to the caller
* of the RPC method as-is.
*/
/**
* The generated invocation function is returned by
* {@link LuCI.rpc#declare rpc.declare()} and encapsulates a single
* RPC method call.
*
* Calling this function will execute a remote `ubus` HTTP call request
* using the arguments passed to it as arguments and return a promise
* resolving to the received reply values.
*
* @callback LuCI.rpc~invokeFn
*
* @param {...*} params
* The parameters to pass to the remote procedure call. The given
* positional arguments will be named to named RPC parameters according
* to the names specified in the `params` array of the method declaration.
*
* Any additional parameters exceeding the amount of arguments in the
* `params` declaration are passed as private extra arguments to the
* declared filter function.
*
* @return {Promise<*>}
* Returns a promise resolving to the result data of the remote `ubus`
* RPC method invocation, optionally substituted and filtered according
* to the `expect` and `filter` declarations.
*/
/**
* Describes a remote RPC call procedure and returns a function
* implementing it.
*
* @param {LuCI.rpc.DeclareOptions} options
* If any object names are given, this function will return the method
* signatures of each given object.
*
* @returns {LuCI.rpc~invokeFn}
* Returns a new function implementing the method call described in
* `options`.
*/
declare(options) {
return Function.prototype.bind.call(function(rpc, options, ...args) {
return new Promise((resolve, reject) => {
/* build parameter object */
let p_off = 0;
const params = { };
if (Array.isArray(options.params))
for (p_off = 0; p_off < options.params.length; p_off++)
params[options.params[p_off]] = args[p_off];
/* all remaining arguments are private args */
const priv = [ undefined, undefined ];
for (; p_off < args.length; p_off++)
priv.push(args[p_off]);
/* store request info */
const req = {
expect: options.expect,
filter: options.filter,
resolve,
reject,
params,
priv,
object: options.object,
method: options.method,
raise: options.reject
};
/* build message object */
const msg = {
jsonrpc: '2.0',
id: rpcRequestID++,
method: 'call',
params: [
rpcSessionID,
options.object,
options.method,
params
]
};
/* call rpc */
rpc.call(msg, rpc.parseCallReply.bind(rpc, req), options.nobatch);
});
}, this, this, options);
},
/**
* Returns the current RPC session id.
*
* @returns {string}
* Returns the 32 byte session ID string used for authenticating remote
* requests.
*/
getSessionID() {
return rpcSessionID;
},
/**
* Set the RPC session id to use.
*
* @param {string} sid
* Sets the 32 byte session ID string used for authenticating remote
* requests.
*/
setSessionID(sid) {
rpcSessionID = sid;
},
/**
* Returns the current RPC base URL.
*
* @returns {string}
* Returns the RPC URL endpoint to issue requests against.
*/
getBaseURL() {
return rpcBaseURL;
},
/**
* Set the RPC base URL to use.
*
* @param {string} url
* Sets the RPC URL endpoint to issue requests against.
*/
setBaseURL(url) {
rpcBaseURL = url;
},
/**
* Translates a numeric `ubus` error code into a human readable
* description.
*
* @param {number} statusCode
* The numeric status code.
*
* @returns {string}
* Returns the textual description of the code.
*/
getStatusText(statusCode) {
switch (statusCode) {
case 0: return _('Command OK');
case 1: return _('Invalid command');
case 2: return _('Invalid argument');
case 3: return _('Method not found');
case 4: return _('Resource not found');
case 5: return _('No data received');
case 6: return _('Permission denied');
case 7: return _('Request timeout');
case 8: return _('Not supported');
case 9: return _('Unspecified error');
case 10: return _('Connection lost');
default: return _('Unknown error code');
}
},
/**
* Registered interceptor functions are invoked before the standard reply
* parsing and handling logic.
*
* By returning rejected promises, interceptor functions can cause the
* invocation function to fail, regardless of the received reply.
*
* Interceptors may also modify their message argument in-place to
* rewrite received replies before they're processed by the standard
* response handling code.
*
* A common use case for such functions is to detect failing RPC replies
* due to expired authentication in order to trigger a new login.
*
* @callback LuCI.rpc~interceptorFn
*
* @param {*} msg
* The unprocessed, JSON decoded remote RPC method call reply.
*
* Since interceptors run before the standard parsing logic, the reply
* data is not verified for correctness or filtered according to
* `expect` and `filter` specifications in the declarations.
*
* @param {Object} req
* The related request object which is an extended variant of the
* declaration object, allowing access to internals of the invocation
* function such as `filter`, `expect` or `params` values.
*
* @return {Promise<*>|*}
* Interceptor functions may return a promise to defer response
* processing until some delayed work completed. Any values the returned
* promise resolves to are ignored.
*
* When the returned promise rejects with an error, the invocation
* function will fail too, forwarding the error to the caller.
*/
/**
* Registers a new interceptor function.
*
* @param {LuCI.rpc~interceptorFn} interceptorFn
* The interceptor function to register.
*
* @returns {LuCI.rpc~interceptorFn}
* Returns the given function value.
*/
addInterceptor(interceptorFn) {
if (typeof(interceptorFn) == 'function')
rpcInterceptorFns.push(interceptorFn);
return interceptorFn;
},
/**
* Removes a registered interceptor function.
*
* @param {LuCI.rpc~interceptorFn} interceptorFn
* The interceptor function to remove.
*
* @returns {boolean}
* Returns `true` if the given function has been removed or `false`
* if it has not been found.
*/
removeInterceptor(interceptorFn) {
const oldlen = rpcInterceptorFns.length;
let i = oldlen;
while (i--)
if (rpcInterceptorFns[i] === interceptorFn)
rpcInterceptorFns.splice(i, 1);
return (rpcInterceptorFns.length < oldlen);
}
});