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UTF-8 Encoding Error When Accessing WeBWorK via Brightspace LTI

UTF-8 Encoding Error When Accessing WeBWorK via Brightspace LTI

by Bianca Sosnovski -
Number of replies: 1

Hi everyone,

We’re running a WeBWorK server on version 2.19. Everything had been functioning well until today, when we re-integrated WeBWorK with Brightspace. During the Spring semester, students accessed WeBWorK through direct login while we performed system upgrades and resolved other issues.

We're not certain whether the current problem is related to the Brightspace integration, but I’ve had to recreate a few faculty accounts due to the following error message:

DBD::mysql::st execute failed: Incorrect string value: '\xE2\x80\xAFAM' for column 'comment' at row 1 at /opt/webwork/webwork2/lib/WeBWorK/DB/Schema/NewSQL/Std.pm line 930.


This error occurs when trying to access WeBWorK via an LTI link in Brightspace. It affects accounts that were originally created on a much older version of our WeBWorK server (circa 2018–2020) and later imported during our full server rebuild in the Spring. Interestingly, this issue doesn’t occur with new accounts using the same LTI links. At least one of the affected accounts run fine in the spring with the direct student login.


When checking the affected courses in Course Administration, the database tables appear fine and do not indicate that any upgrades are needed.


In addition to recreating the affected accounts, is there any alternative fix for this issue? Has anyone encountered and resolved a similar UTF-8 encoding problem in the WeBWorK database?


Any suggestions would be greatly appreciated.


Thanks,

                        

    
    
    
                            
    
    
                                

                                        
                                

    
                            
                    

                

            

        

    
        

                

                    

                        
                
                        

                            

                                        

                                                
                                        

                                

                                        In reply to Bianca Sosnovski
                                        
Re: UTF-8 Encoding Error When Accessing WeBWorK via Brightspace LTI

                                        

                                            by Danny Glin - 
                                        

                                

                            

                
                            

                                        

                                        

                
                                

                                    

                                        
If you restore a course from an archive, then the database tables will use the encoding that was used when the course was archived, so even if your new server is set to use utf8mb4, any courses imported from previous versions might not be.  Moreover the "Upgrade Courses" feature in Course Administration doesn't handle upgrades of character sets and collations, so it wouldn't fix this issue.
In your case the error appears to be coming from the comment field, so it may be sufficient to log into the course and use the Accounts Manager to delete any text from the comment field for the affected user(s).
If you want to make sure that everything is set up for utf8mb4, you can try running the upgrade-database-to-utf8mb4.pl script, but I recommend backing up your database before doing this.