webpack.fixnedbpath.js

// Prevent nedb from substituting browser storage when running from the
// Electron renderer thread.
class FixNedb {
    apply(resolver) {
      resolver
        // Plug in after the description file (package.json) has been
        // identified for the import, because we'll depend on it for some of
        // the logic below.
        .getHook("beforeDescribed-relative")
        .tapAsync(
          "FixNedbForElectronRenderer",
          (request, resolveContext, callback) => {
            // Detect that the import is from NeDB via the description file
            // dectect for the import. Calling `callback` with no parameters
            // "bails", which proceeds with the normal resolution process.
            if (!request.descriptionFileData.name === "nedb") {
              return callback()
            }
   
            // When a require/import matches the target files from nedb, we
            // can form the paths to the Node-specific versions of the files
            // relative to the location of the description file. We can then
            // short-circuit the Webpack resolution process by calling the
            // callback with the finalized request object -- meaning that
            // the `path` is pointing at the file that should be imported.
            let relativePath
            if (
              request.path.startsWith(
                resolver.join(request.descriptionFileRoot, "lib/storage")
              )
            ) {
              relativePath = "lib/storage.js"
            } else if (
              request.path.startsWith(
                resolver.join(
                  request.descriptionFileRoot,
                  "lib/customUtils"
                )
              )
            ) {
              relativePath = "lib/customUtils.js"
            } else {
              // Must be a different file from NeDB, so bail.
              return callback()
            }
   
            const path = resolver.join(
              request.descriptionFileRoot,
              relativePath
            )
            const newRequest = Object.assign({}, request, { path })
            callback(null, newRequest)
          }
        )
    }
  }

module.exports = FixNedb