apollo-errors
Machine-readable custom errors for Apollostack's GraphQL server
Example from Apollo Day
Installation and usage
Install the package:
npm install apollo-errors
Create some errors:
; const FooError = ;
Hook up formatting:
;;;;; const app = ; app; app
Throw some errors:
; const resolverThatThrowsError = { throw data: something: 'important' internalData: error: `The SQL server died.` ;}
Witness glorious simplicity:
POST /graphql (200)
The internalData
property is meant for data you want to store on the error object (e.g. for logging), but not send out to your end users.
You can utilize this data for logging purposes.
; { const originialError = error; if // log internalData to stdout but not include it in the formattedError console; return }
API
ApolloError ({ [time_thrown: String, data: Object, internalData: object message: String ]})
Creates a new ApolloError object. Note that ApolloError
in this context refers
to an error class created and returned by createError
documented below. Error can be
initialized with a custom time_thrown
ISODate (default is current ISODate), data
object (which will be merged with data specified through createError
, if it exists), internalData
object (which will be merged with internalData specified trough createError
) and message
(which will override the message specified through createError
).
createError(name, {message: String, [data: Object, internalData: object, options: Object]}): ApolloError
Creates and returns an error class with the given name
and message
, optionally initialized with the given data
, internalData
and options
. data
and internalData
passed to createError
will later be merged with any data passed to the constructor.
Options (default):
showPath
(false): Preserve the GraphQLErrorpath
data.showLocations
(false): Preserve the GraphQLErrorlocations
data.
formatError (error, strict = false): ApolloError|Error|null
If the error is a known ApolloError, returns the serialized form of said error.
Otherwise, if strict is not truthy, returns the original error passed into formatError.
Otherwise, if strict is truthy, returns null.
isInstance (error): Boolean
Returns true if the error is an instance of an ApolloError. Otherwise, returns false