graphql-mesh: why odata handler throws error when serving my local endpoint - graphql

Question

I am trying to follow the example in the GraphQL-Mesh and replace the endpoint with my own to see how it works. Default github example works however when I try to server the mesh for my example, it throws the following error:
$ "C:\Kiran\example\GraphQLMesh\node_modules\.bin\graphql-mesh" serve
Debugger listening on ws://127.0.0.1:64627/889629dc-8f00-446e-8927-5bdcd2791e10
For help, see: https://nodejs.org/en/docs/inspector
Debugger attached.
(node:13408) ExperimentalWarning: The fs.promises API is experimental
error: Unable to serve mesh: Cannot read property 'concat' of undefined {"stack":"TypeError: Cannot read property 'concat' of undefined\n at schemas.forEach (C:\\Kiran\\example\\GraphQLMesh\\node_modules\\#graphql-mesh\\odata\\index.cjs.js:493:51)\n at Array.forEach (<anonymous>)\n at ODataHandler.getMeshSource (C:\\Kiran\\example\\GraphQLMesh\\node_modules\\#graphql-mesh\\odata\\index.cjs.js:471:67)\n at process._tickCallback (internal/process/next_tick.js:68:7)"}
Waiting for the debugger to disconnect...
Done in 9.93s.
Waiting for the debugger to disconnect...
my .meshrc.yaml is very simple as shown below
sources:
- name: Mytest
handler:
odata:
baseUrl: http://localhost:6001/odata/v1/
batch: multipart
expandNavProps: true
serve:
exampleQuery: northwind-example.graphql
and package.json also is just copy of what is in the github
{
"name": "odata-example",
"version": "0.7.30",
"license": "MIT",
"private": true,
"scripts": {
"start": "graphql-mesh serve"
},
"dependencies": {
"#graphql-mesh/cli": "^0.12.1",
"#graphql-mesh/odata": "0.7.1",
"graphql": "^15.4.0"
}
}
When I hit the odata endpoint (http://localhost:6001/odata/v1/) on Postman, I see the following response:
Header
Status Code: 200 OK
content-type: application/json; odata.metadata=minimal; odata.streaming=true; charset=utf-8
date: Sat, 05 Dec 2020 06:52:51 GMT
odata-version: 4.0
server: Kestrel
transfer-encoding: chunked
Response
{
"#odata.context": "http://localhost:6001/odata/v1/$metadata",
"value": [{
"name": "Products",
"kind": "EntitySet",
"url": "Products"
}, {
"name": "Categories",
"kind": "EntitySet",
"url": "Categories"
}, {
"name": "Suppliers",
"kind": "EntitySet",
"url": "Suppliers"
}]
}
My example query is also very simple as shown below:
query fetchCatagories {
myCatagories {
CategoryId
CategoryName
Description
Products {
ProductName
OrderDetails {
OrderId
}
}
Catagories(queryOptions: { top: 1 }) {
Description
}
}
}
What am I missing in my example to get the mesh working and generating the GraphQL endpoint?
Also do I really need an example.graphql for OData as any OData service will have /$metadata endpoint that exposes the schema?
Update 1
Also I cannot get this to work with public odata endpoint like https://services.odata.org/V3/OData/OData.svc/
only the default example endpoints work
https://graph.microsoft.com/${GRAPH_VERSION:v1.0}
https://services.odata.org/TripPinRESTierService/(S(qzsyox3345c15qeq305pblvw))/
What is going on here?

Answer 1

if you run in to this issue, its a bug in the odata module and PR fix is available here