How Do I Fix 'Metadata Load Error' in AGE Viewer?

When using npm start to start AGE Viewer, I get the following error in my terminal.

Error: Not connected
    at _callee4$ (/home/hallixon/age-viewer/backend/src/controllers/databaseController.js:64:19)
    at tryCatch (/home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/regeneratorRuntime.js:44:17)
    at Generator.<anonymous> (/home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/regeneratorRuntime.js:125:22)
    at Generator.next (/home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/regeneratorRuntime.js:69:21)
    at asyncGeneratorStep (/home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/asyncToGenerator.js:3:24)
    at _next (/home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/asyncToGenerator.js:22:9)
    at /home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/asyncToGenerator.js:27:7
    at new Promise (<anonymous>)
    at apply (/home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/asyncToGenerator.js:19:12)
    at getMetadata (/home/hallixon/age-viewer/backend/src/controllers/databaseController.js:66:6)
info: ::ffff:127.0.0.1 - - [05/Aug/2023:04:50:51 +0000] "POST /api/v1/db/meta HTTP/1.1" 500 51
 {"timestamp":"2023-08-05 05:50:51"}
Error: Not connected
    at _callee3$ (/home/hallixon/age-viewer/backend/src/controllers/databaseController.js:54:19)
    at tryCatch (/home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/regeneratorRuntime.js:44:17)
    at Generator.<anonymous> (/home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/regeneratorRuntime.js:125:22)
    at Generator.next (/home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/regeneratorRuntime.js:69:21)
    at asyncGeneratorStep (/home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/asyncToGenerator.js:3:24)
    at _next (/home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/asyncToGenerator.js:22:9)
    at /home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/asyncToGenerator.js:27:7
    at new Promise (<anonymous>)
    at apply (/home/hallixon/age-viewer/backend/node_modules/@babel/runtime/helpers/asyncToGenerator.js:19:12)
    at getStatus (/home/hallixon/age-viewer/backend/src/controllers/databaseController.js:56:6)
info: ::ffff:127.0.0.1 - - [05/Aug/2023:04:50:51 +0000] "GET /api/v1/db HTTP/1.1" 500 51
 {"timestamp":"2023-08-05 05:50:51"}
info: ::ffff:127.0.0.1 - - [05/Aug/2023:04:50:51 +0000] "GET /api/v1/miscellaneous HTTP/1.1" 304 -
 {"timestamp":"2023-08-05 05:50:51"}

Still, AGE Viewer runs just fine on port 3000.

Now, I'm trying to connect to my database on Viewer, and I get the error 'Metadata Load Error'.

I also noticed that information about my graphs, nodes, and edges are missing. Clicking the dropdown to select Current Graph does not show any of my graphs.

I expected that information about the existing graphs, nodes, and edges in the database were displayed, and that there were no errors on connection to my database.

Solution

The error may be happening because you are using pg version > 12. In that case there should be a .version sql file in the backend folder of age-viewer. Because there's a code to fetch the sql version and match it with the .sql file, without which metadata endpoint will not give proper response, and so graph will also not load.