Better error handling

[kmcginnes]

Description

Improves the error handling within Graph Explorer and the proxy server in various ways.

Client Side Changes

• Add createDisplayError() function to map errors to friendly errors that can be displayed to the user (this will grow over time)
• Use createDisplayError() in schema sync and keyword search
• Check if response.ok for any useGEFetch() requests and throw an error if it is not
• Attempt to decode error response bodies in a safe way

Server Side Changes

• Move routes out of unnecessary async closure
• Remove duplicate app.use(errorHandler)
• Send error responses from the remote database through the proxy back to the client with minimal changes

Validation

• When reviewing the code it will be useful to turn on the "ignore whitespace changes" feature in GitHub
• Added tests for errors I know about
• Disconnect VPC or wifi to get the connection refused error
• Set fetch timeout for connection to something low (e.g. 50 ms) to get the fetch timeout error
• Connect to large RDF dataset and do a keyword search with all nodes types, all predicates, and partial precision, then use a long series of characters in the query field (e.g. "aaaaaaaaaaaaa") to get the server timeout error

Schema sync failure (connection refused)

Fetch timeout

Neptune long query server timeout

Related Issues

Fixes issue #275

Check List

• I confirm that my contribution is made under the terms of the Apache 2.0 license.
• I have run pnpm run checks to ensure code compiles and meets standards.
• I have run pnpm run test to check if all tests are passing.
• I've covered new added functionality with unit tests if necessary.

[codecov]

Codecov Report

Attention: Patch coverage is 45.21739% with 63 lines in your changes are missing coverage. Please review.

Project coverage is 12.15%. Comparing base (7fbac1e) to head (2849d14).

Files	Patch %	Lines
...ackages/graph-explorer/src/connector/useGEFetch.ts	0.00%	46 Missing ⚠️
packages/graph-explorer/src/hooks/useSchemaSync.ts	0.00%	14 Missing ⚠️
...src/modules/KeywordSearch/useKeywordSearchQuery.ts	0.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #283      +/-   ##
==========================================
+ Coverage   12.02%   12.15%   +0.13%     
==========================================
  Files         410      411       +1     
  Lines       30481    30575      +94     
  Branches      764      776      +12     
==========================================
+ Hits         3665     3717      +52     
- Misses      26483    26525      +42     
  Partials      333      333              

Flag	Coverage Δ
unittests	12.15% <45.21%> (+0.13%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[vkagamlyk]

LGTM

[michaelnchin]

Thanks @kmcginnes ! This should substantially improve user debugging.