Why does this AWS AppSync list operation using OR return an empty list even when part of the OR returns truthy values? - graphql

Context:
I am trying to query for all notifications sent or received by a user in my mobile app, and am getting results that (I think) show that AWS AppSync's OR filtering is slightly broken (or that I do not understand how it works)
Note that I am performing these queries using AWS AppSync Queries, but the results are consistent when using their GUI or by sending the queries from the React Native app
Here is my list query using the OR statement
query listAllNotifsForUser {
listNotifications(filter: {sentUserID: {eq: "arbitrary-id-1"}, or: {receivedUserID: {eq: "arbitrary-id-1"}}}) {
items {
id
}
nextToken
}
}
This query returns
"data": {
"listNotifications": {
"items": [],
"nextToken": null
}
Here is my query when listing specifically notifications that have the sentUserID equal to arbitrary-id-1 (no OR statement, only the first half of the OR filter from above)
query listAllNotifsForUser {
listNotifications(filter: {sentUserID: {eq: "arbitrary-id-1"}}) {
items {
id
}
nextToken
}
}
and here is the result from that query
{
"data": {
"listNotifications": {
"items": [
{
"id": "88d204c8-7346-4f69-bc6a-c1e5db1ce5f4"
},
{
"id": "29e03351-75f0-46b2-933b-c3cca43a6067"
},
{
"id": "e21cf81a-7cb3-4331-90af-6ef266f75820"
},
{
"id": "17b42150-ae7c-4852-a58c-85d73ed2e247"
}
],
"nextToken": null
}
}
}
Notice the ONLY difference between these two queries is the removal of the 'or' and the second half of the boolean check, which from basic knowledge of programming, one would not imagine this should ever limit the results compared to a single boolean statement
Any thoughts?

I did this on my AppSync console and it worked:
query MyQuery {
listJobListings(filter: {or: [{ city: {eq: "Chongqing City"} }, { city: {eq: "Beijing"} }]}) {
nextToken
items {
city
}
}
}
Which means you'll need to do this:
query listAllNotifsForUser {
listNotifications(filter: {or: [{ sentUserID: {eq: "user-id"} }, { sentUserID: {eq: "user-id"} }]}) {
items {
id
}
nextToken
}
}
More information here

Related

AppSync/GraphQL filter nested objects

I have a DynamoDB table with the following structure
site (String)
addresses (List)
|-> address (String)
|-> isCurrent (Boolean)
I want to filter a specific site for either current or all address(s).
query MyQuery {
getSite(site: "site1", isCurrent: true) {
site
addresses{
adress
isCurrent
}
the schema looks like
type Sites{
site: String!
addresses: [Address]
}
type Address {
address: String
isCurrent: Boolean
}
type Query{
getSite(site: String!, isCurrent:Boolean)
}
The Resolver I have
#if($ctx.args.isCurrent)
{
"version": "2017-02-28",
"operation": "Query",
"query": {. // Filter for specific Site
"expression": "#siteName = :siteNameByUser",
"expressionNames": {
"#siteName": "site"
},
"expressionValues": {
":siteNameByUser": {"S": $util.toJson($ctx.args.site)}
}
}, // Filter Current Address(s)
"filter": {
"expression": "addresses.isCurrent = :isActiveByUser",
"expressionValues": {
":isActiveByUser": $util.dynamodb.toDynamoDBJson($ctx.args.isCurrent)
}
}
}
#else
{
"version": "2017-02-28",
"operation": "GetItem",
"key": {
"site": $util.dynamodb.toDynamoDBJson($ctx.args.site)
}
}
#end
I'm not getting any results when I add filter ( it works without the filter or with isCurrent=False ).
I am trying to filter the inner objects in Addresses list based on a value user sends for isCurrent. Any help is much appreciated!
I tried writing a resolver with a filter condition on an inner value (addresses.isCurrent).
{
"version": "2017-02-28",
"operation": "Query",
"query": {. // Filter for specific Site
"expression": "#siteName = :siteNameByUser",
"expressionNames": {
"#siteName": "site"
},
"expressionValues": {
":siteNameByUser": {"S": $util.toJson($ctx.args.site)}
}
}, // Filter Current Address(s)
"filter": {
"expression": "addresses.isCurrent = :isActiveByUser",
"expressionValues": {
":isActiveByUser": $util.dynamodb.toDynamoDBJson($ctx.args.isCurrent)
}
}
}
Apparently, DynamoDB does not let you filter on Complex object types like List of Maps (your case), see a related question: DynamoDB: How to store a list of items
I'd suggest changing your DynamoDB table data model if possible to site, address, isCurrentAddress to achieve what you are trying to do. Or you can
write logic in VTL response mapping template to filter your result set based on isCurrentAddress value. Btw AppSync recently launched JavaScript resolvers, go through that and see if that helps in writing your resolver logic simpler.

grpc/protobuffer ask for specific fields

GraphQL lets you ask for specific fields, the response contains only the fields that you had asked for. For example:
a graphql query like:
{
hero {
name
}
}
will return:
{
"data": {
"hero": {
"name": "R2-D2"
}
}
}
where as a graphQl query like:
{
hero {
name
friends {
name
}
}
}
would return:
{
"data": {
"hero": {
"name": "R2-D2",
"friends": [
{
"name": "Luke"
},
{
"name": "Han Solo"
},
{
"name": "Leia"
}
]
}
}
}
Is there a similar mechanism/library/pattern that can be used in gRPC to achieve the same?
FieldMask is similar in protobuf. It is a list of fields to retain, so the first example would be paths: "hero.name" and the second would be paths: ["hero.name", "hero.friends.name"].
It is probably most frequently used to specify which fields should be changed in an update. But it can equally be used to specify the fields that should be returned.
The server can either process the FieldMask directly (e.g., only using the listed fields in a SELECT SQL query), or it can retrieve all the information and filter the result using FieldMaskUtil.merge() to copy just the requested fields into a new proto message to return to the client.

Nested query in Strapi GraphQL

I have a document structured as follows, more or less:
post {
_id
title
isPublished
}
user {
_id
username
name
[posts]
}
I know I can query fields like postConnection and userConnection with the aggregate subfield in order to query a count of all objects. But how do I get the total count of all posts by a given user?
I was able to come up with this:
{
postsConnection(where: {isPublished: true}){
groupBy{
author{
key
connection{
aggregate{
count
}
}
}
}
}
}
But this returns (expectedly) something like this:
{
"data": {
"postsConnection": {
"groupBy": {
"author": [
{
"key": "5c9136976238de2cc029b5d3",
"connection": {
"aggregate": {
"count": 5
}
}
},
{
"key": "5c99d5d5fcf70010b75c07d5",
"connection": {
"aggregate": {
"count": 3
}
}
}
]
}
}
}
}
As you can see, it returns post counts for all authors in an array. What I need is to be able to return the count for only one specific user and not by _id (which is what the key field seems to map to) but by another unique field I have in the users collection, i.e. username.
Is that possible?
Need to pass in a parameter to either the query or the field to return specific data

Nested pagination with relay graphql

Currently having an issue with the relay approach to nested pagination. An example below to illustrate what I mean:
{
"data": {
"locations": {
"edges": [
{
"node": {
"id": "Location_254"
}
},
{
"node": {
"id": "Location_247"
}
},
{
"node": {
"id": "Location_217"
}
},
]
}
}
Here I have 3 locations returned from a query. Now I wanted to paginate on these locations and look at their 'history'.
query {
locations {
edges {
node {
history(
first:10
after:"eyJzbm9vemVJZCI6Mzg3fQ=="
)
}
}
}
}
This would paginate 10 results after the specified cursor. My issue is, is that this cursor is specific to the location it was obtained from. The cursor it is referring to paginate after, only applies to the location it came from.
Nested pagination tries to paginate on ALL locations here, when in actuality, the cursor being used, was grabbed from a specific location.
Am I seeing this incorrectly, or is there a better way I could be approaching this issue?
Regards, Sebastian

GraphQL Github API formatting

I am wondering how to deal with the following problem. I am using GraphQL to query the v4 Github API with the following query:
{
viewer {
repositories(first: 30) {
edges {
node {
name
}
}
}
}
}
This gets me a response that looks like so:
{
"data": {
"viewer": {
"repositories": {
"edges": [
{
"node": {
"name": "test-repo"
}
},
{
"node": {
"name": "another-repo"
}
}
]
}
}
}
}
I am pretty new to GraphQL, I understand that in my query I need to provide the edges and nodes but I would rather get a response back in this kind of way because I am not interested to know about "edges" and "nodes" in my frontend:
{
"data": {
"viewer": {
"repositories": [
{
"name": "test-repo"
},
{
"name": "another-repo"
}
]
}
}
}
}
I am guessing this kind of response is normal for GraphQL but it would be pretty cumbersome to rewrite to response all the time for easier usage in my frontend. Is there some way to emit the "edges" and "nodes" and get the formatting that I would like or is this simply all up to me to deal with?
I have looked at some libraries like Apollo but I have no idea is this is a right fit to deal with things like this. Hopefully someone a bit more experienced with GraphQL could tell me something more.
Sometimes, services provides two endpoints: Relay endpoint (with edges and nodes) and simple endpoint.
Looks like GitHub only have a Relay endpoint. In this case, the only thing you can do is to manually format the response on your frontend.
Actually, such complex response structure is needed because we often need to do a pagination. Take a look at the example:
{
getArticle(id: "some-id") {
id
userId
user {
id
name
}
tags(first: 10, after: "opaqueCursor") {
edges {
node {
id
name
itemsCount
}
}
pageInfo {
hasNextPage
hasPreviousPage
endCursor
startCursor
}
}
}
}
pageInfo is located at the same level as edges.
So if you later will need to do a pagination, it would be better to keep the response format as is.
You can remove the edges query if you know you aren't searching along those relationships. Cursor-based pagination will work by checking the pageInfo value hasNextPage and using endCursor as the after query parameter:
viewer {
repositories(first: 30,after:"<CURSOR_STRING>") {
totalCount
pageInfo{
hasNextPage
endCursor
}
nodes{
name
}
}
}
returns
"viewer": {
"repositories": {
"totalCount": 38,
"pageInfo": {
"hasNextPage": true,
"endCursor": "Y3Vyc29yOnYyOpHOAl/5mw=="
},
"nodes": [
{
"name": "AllStarRoom"
},
{
"name": "shimsham"
},
{
"name": "Monitor-Docs"
}
]
}
}

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