Fixes bug introduced in v0.7.2 wherein matlab-proxy would crash when MATLAB is not on the path.

Introduces new error messages when MATLAB is not found on path or when specified incorrectly using the MWI_CUSTOM_MATLAB_ROOT environment variable.

Author: Prabhakar Kumar

gui/src/components/App/App.spec.js

@@ -151,7 +151,7 @@ describe('App Component', () => {
     });
 
 
-    const paragraphElements = [...container.getElementsByTagName('p')];
+    const paragraphElements = [...container.getElementsByTagName('pre')];
 
 
     expect(
@@ -173,7 +173,7 @@ describe('App Component', () => {
       initialState: initialState,
     });
 
-    const paragraphElements = [...container.getElementsByTagName('p')];
+    const paragraphElements = [...container.getElementsByTagName('pre')];
 
     expect(
       paragraphElements.some((p) =>

gui/src/components/Error/Error.css

@@ -1,12 +1,19 @@
-/* Copyright (c) 2020-2022 The MathWorks, Inc. */
+/* Copyright (c) 2020-2023 The MathWorks, Inc. */
 
 #error .alert {
     padding: 0;
     margin-bottom: 0;
     border-radius: 10px;
 }
 
-#error .modal-body,
+#error .modal-body pre { 
+    background-color: hsla(0, 0%, 100%, 0);
+    border: none;
+    font-family: inherit;
+    font-size: 15px;
+    white-space: pre-wrap;
+}
+
 #error .modal-header {
     padding-left: 45px;
 }

gui/src/components/Error/Error.spec.js

@@ -1,4 +1,4 @@
-// Copyright (c) 2020-2022 The MathWorks, Inc.
+// Copyright (c) 2020-2023 The MathWorks, Inc.
 
 import React from 'react';
 import Error from './index';
@@ -22,7 +22,7 @@ describe('Error Component', () => {
   it('should render without crashing ', () => {
     const { container } = render(<Error message={message} />);
 
-    const paragraphs = [...container.getElementsByTagName('p')];
+    const paragraphs = [...container.getElementsByTagName('pre')];
 
     expect(paragraphs.some((p) => p.textContent === message)).toBeTruthy();
   });

gui/src/components/Error/index.js

@@ -1,4 +1,4 @@
-// Copyright (c) 2020-2022 The MathWorks, Inc.
+// Copyright (c) 2020-2023 The MathWorks, Inc.
 
 import React from 'react';
 import PropTypes from 'prop-types';
@@ -28,7 +28,7 @@ function Error({ message, logs, children }) {
                         <h4 className="modal-title alert_heading">Error</h4>
                     </div>
                     <div className="modal-body">
-                        <p>{message}</p>
+                        <pre>{message}</pre>
                         <Linkify>{logReport}</Linkify>
                         {children}
                     </div>

matlab_proxy/app.py

@@ -19,7 +19,11 @@
 from matlab_proxy.util import list_servers, mwi
 from matlab_proxy.util.mwi import environment_variables as mwi_env
 from matlab_proxy.util.mwi import token_auth
-from matlab_proxy.util.mwi.exceptions import AppError, InvalidTokenError, LicensingError
+from matlab_proxy.util.mwi.exceptions import (
+    AppError,
+    InvalidTokenError,
+    LicensingError,
+)
 
 mimetypes.add_type("font/woff", ".woff")
 mimetypes.add_type("font/woff2", ".woff2")
@@ -109,12 +113,12 @@ async def create_status_response(app, loadUrl=None):
         {
             "matlab": {
                 "status": await state.get_matlab_state(),
-                "version": state.settings["matlab_version"],
+                "version": state.settings.get("matlab_version", "Unknown"),
             },
             "licensing": marshal_licensing_info(state.licensing),
             "loadUrl": loadUrl,
             "error": marshal_error(state.error),
-            "wsEnv": state.settings["ws_env"],
+            "wsEnv": state.settings.get("ws_env", ""),
         }
     )
 
@@ -160,7 +164,6 @@ async def authenticate_request(req):
     Returns:
         JSONResponse: JSONResponse object containing information about authentication status and error if any.
     """
-    state = req.app["state"]
     if await token_auth.authenticate_request(req):
         logger.debug("!!!!!! REQUEST IS AUTHORIZED !!!!")
         authStatus = True

matlab_proxy/app_state.py

@@ -15,10 +15,9 @@
 from matlab_proxy.util.mwi.exceptions import (
     EmbeddedConnectorError,
     EntitlementError,
-    InternalError,
+    FatalError,
     LicensingError,
     MatlabError,
-    MatlabInstallError,
     OnlineLicensingError,
     XvfbError,
     log_error,
@@ -70,11 +69,12 @@ def __init__(self, settings):
         self.logs = {
             "matlab": deque(maxlen=200),
         }
-        self.error = None
-        # Start in an error state if MATLAB is not present
-        if not self.is_matlab_present():
-            self.error = MatlabInstallError("'matlab' executable not found in PATH")
-            logger.error("'matlab' executable not found in PATH")
+
+        # Initialize with the error state from the initialization of settings
+        self.error = settings["error"]
+
+        if self.error is not None:
+            self.logs["matlab"].clear()
             return
 
         # Keep track of when the Embedded connector starts.
@@ -153,8 +153,8 @@ async def init_licensing(self):
             self.__delete_cached_licensing_file()
 
         # NLM Connection String set in environment
-        elif self.settings["nlm_conn_str"] is not None:
-            nlm_licensing_str = self.settings["nlm_conn_str"]
+        elif self.settings.get("nlm_conn_str", None) is not None:
+            nlm_licensing_str = self.settings.get("nlm_conn_str")
             logger.debug(f"Found NLM:[{nlm_licensing_str}] set in environment")
             logger.debug(f"Using NLM string to connect ... ")
             self.licensing = {
@@ -395,26 +395,17 @@ def is_licensed(self):
                 return True
         return False
 
-    def is_matlab_present(self):
-        """Is MATLAB install accessible?
-
-        Returns:
-            Boolean: True if MATLAB is present in the system. False otherwise.
-        """
-
-        return self.settings["matlab_path"] is not None
-
     async def update_entitlements(self):
         """Speaks to MW and updates MHLM entitlements
 
         Raises:
-            InternalError: When licensing is None or when licensing type is not MHLM.
+            FatalError: When licensing is None or when licensing type is not MHLM.
 
         Returns:
             Boolean: True if update was successful
         """
         if self.licensing is None or self.licensing["type"] != "mhlm":
-            raise InternalError(
+            raise FatalError(
                 "MHLM licensing must be configured to update entitlements!"
             )
 
@@ -722,26 +713,8 @@ async def start_matlab(self, restart_matlab=False):
 
         Args:
             restart_matlab (bool, optional): Whether to restart MATLAB. Defaults to False.
-
-        Raises:
-            Exception: When MATLAB is already running and restart is False.
-            Exception: When MATLAB is not licensed.
         """
 
-        # FIXME
-        if await self.get_matlab_state() != "down" and restart_matlab is False:
-            raise Exception("MATLAB already running/starting!")
-
-        # FIXME
-        if not self.is_licensed():
-            raise Exception("MATLAB is not licensed!")
-
-        if not self.is_matlab_present():
-            self.error = MatlabInstallError("'matlab' executable not found in PATH")
-            logger.error("'matlab' executable not found in PATH")
-            self.logs["matlab"].clear()
-            return
-
         # Ensure that previous processes are stopped
         await self.stop_matlab()