fetching JSON content (e.g. _graph.json_) or 404 files are breaking local dev E-Tag caching mechanism

[thescientist13]

Type of Change

• New Feature Request
• Documentation / Website
• Improvement / Suggestion
• Bug
• Other (please clarify below)

Summary

Looks like a case was missed as part of #629 / #760 but it seems if a request comes in with 'Content-Type: application/json' the project breaks with an error on the request.

% yarn develop
yarn run v1.22.5
$ greenwood develop
-------------------------------------------------------
Welcome to Greenwood (v0.24.0) ♻️
-------------------------------------------------------
Running Greenwood with the develop command.
Initializing project config
Initializing project workspace contexts
Generating graph of workspace files...
building from local sources...
Started local development server at localhost:1984
Unable to look up greenwood-starter-presentation using NodeJS require.resolve.
Unable to look up greenwood-starter-presentation using NodeJS require.resolve.
Unable to look up greenwood-starter-presentation using NodeJS require.resolve.
Unable to look up greenwood-starter-presentation using NodeJS require.resolve.

  TypeError: inputString.charCodeAt is not a function
      at hashString (file:///Users/owenbuckley/Workspace/github/repos/greenwood-starter-presentation/node_modules/@greenwood/cli/src/lib/hashing-utils.js:6:40)
      at file:///Users/owenbuckley/Workspace/github/repos/greenwood-starter-presentation/node_modules/@greenwood/cli/src/lifecycles/serve.js:141:26
      at dispatch (/Users/owenbuckley/Workspace/github/repos/greenwood-starter-presentation/node_modules/koa-compose/index.js:42:32)
      at file:///Users/owenbuckley/Workspace/github/repos/greenwood-starter-presentation/node_modules/@greenwood/cli/src/lifecycles/serve.js:125:11
      at async file:///Users/owenbuckley/Workspace/github/repos/greenwood-starter-presentation/node_modules/@greenwood/cli/src/lifecycles/serve.js:88:5
      at async file:///Users/owenbuckley/Workspace/github/repos/greenwood-starter-presentation/node_modules/@greenwood/cli/src/lifecycles/serve.js:51:5

Details

Seems to be because this logic passes body right to the hashing function

const inm = ctx.headers['if-none-match'];
const etagHash = hashString(body);

But in the case of JSON, body is an Array, which means it wont have a charAt method since it is not a string. A quick test shows this simple check can solve it.

const etagHash = ctx.headers['content-type'].indexOf('application/json') >= 0
  ? hashString(JSON.stringify(body))
  : hashString(body);

Should probably add a test or figure out how to test for it.

[thescientist13]

Found another edge case, like with TypeScript sourcemaps which are currently not working, so have an empty body and should be excluded from trying to be E-Tag cached.