I need to get a number of items from a GraphQL enabled database (no control over its schema) and output them in the exact order called.
For example, if the database holds the items 1,2,3 in that respective order I need to get them as 3,1,2.
Query:
{items(filter: {id: {_in: ["3","1","2"] } } ) {data}}
Actual result:
{"data": {"items": [{"data": "data-from-1"},{"data": "data-from-2"},{"data": "data-from-3"}]}}
Expected result:
{"data": {"items": [{"data": "data-from-3"},{"data": "data-from-1"},{"data": "data-from-1"}]}}
So I guess that what I'm looking for is a 'meta' operator that relates to other operators rather than the actual query – something like:
sort:["_in"] or orderby:{operator:"_in"}
...but I didn't manage to find out if such a thing exists or not.
So is it possible in general or maybe in some flavour of GraphQL? Or is it my only choice to prebuild a query with aliases and do it like this:
{
_3: items(filter:{id: { _eq: "3" }}){data}
_1: items(filter:{id: { _eq: "1" }}){data}
_2: items(filter:{id: { _eq: "2" }}){data}
}
Which GraphQL client are you using?
If you're using Apollo, and you really don't have access to the schema/resolvers in the server, you can create a local field and resolve it on your own, and so you can manipulate as much as you want.
Reference
https://www.apollographql.com/docs/react/local-state/managing-state-with-field-policies/#defining
Basically, if you're querying a field like:
query {
someQuery(someFilter: {foo: "bar"}) {
items {
data
}
}
}
You can create a local field and write a typePolicy to it. Then you can query something like:
query {
someQuery(someFilter: {foo: "bar"}) {
items {
data
}
parsedItems #client
}
}
Then you can get data from ìtems and resolve parsedItems locally as you want.
Related
Assume you have a GraphQL type and it includes many fields.
How to query all the fields without writing down a long query that includes the names of all the fields?
For example, If I have these fields :
public function fields()
{
return [
'id' => [
'type' => Type::nonNull(Type::string()),
'description' => 'The id of the user'
],
'username' => [
'type' => Type::string(),
'description' => 'The email of user'
],
'count' => [
'type' => Type::int(),
'description' => 'login count for the user'
]
];
}
To query all the fields usually the query is something like this:
FetchUsers{users(id:"2"){id,username,count}}
But I want a way to have the same results without writing all the fields, something like this:
FetchUsers{users(id:"2"){*}}
//or
FetchUsers{users(id:"2")}
Is there a way to do this in GraphQL ??
I'm using Folkloreatelier/laravel-graphql library.
Unfortunately what you'd like to do is not possible. GraphQL requires you to be explicit about specifying which fields you would like returned from your query.
Yes, you can do this using introspection. Make a GraphQL query like (for type UserType)
{
__type(name:"UserType") {
fields {
name
description
}
}
}
and you'll get a response like (actual field names will depend on your actual schema/type definition)
{
"data": {
"__type": {
"fields": [
{
"name": "id",
"description": ""
},
{
"name": "username",
"description": "Required. 150 characters or fewer. Letters, digits, and #/./+/-/_ only."
},
{
"name": "firstName",
"description": ""
},
{
"name": "lastName",
"description": ""
},
{
"name": "email",
"description": ""
},
( etc. etc. ...)
]
}
}
}
You can then read this list of fields in your client and dynamically build a second GraphQL query to get the values of these fields.
This relies on you knowing the name of the type that you want to get the fields for -- if you don't know the type, you could get all the types and fields together using introspection like
{
__schema {
types {
name
fields {
name
description
}
}
}
}
NOTE: This is the over-the-wire GraphQL data -- you're on your own to figure out how to read and write with your actual client. Your GraphQL javascript library may already employ introspection in some capacity. For example, the apollo codegen command uses introspection to generate types.
2022 Update
Since this answer was originally written, it is now a recommended security practice to TURN OFF introspection in production. Reference: Why you should disable GraphQL introspection in production.
For an environment where introspection is off in production, you could use it in development as a way to assist in creating a static query that was used in production; you wouldn't actually be able to create a query dynamically in production.
I guess the only way to do this is by utilizing reusable fragments:
fragment UserFragment on Users {
id
username
count
}
FetchUsers {
users(id: "2") {
...UserFragment
}
}
I faced this same issue when I needed to load location data that I had serialized into the database from the google places API. Generally I would want the whole thing so it works with maps but I didn't want to have to specify all of the fields every time.
I was working in Ruby so I can't give you the PHP implementation but the principle should be the same.
I defined a custom scalar type called JSON which just returns a literal JSON object.
The ruby implementation was like so (using graphql-ruby)
module Graph
module Types
JsonType = GraphQL::ScalarType.define do
name "JSON"
coerce_input -> (x) { x }
coerce_result -> (x) { x }
end
end
end
Then I used it for our objects like so
field :location, Types::JsonType
I would use this very sparingly though, using it only where you know you always need the whole JSON object (as I did in my case). Otherwise it is defeating the object of GraphQL more generally speaking.
GraphQL query format was designed in order to allow:
Both query and result shape be exactly the same.
The server knows exactly the requested fields, thus the client downloads only essential data.
However, according to GraphQL documentation, you may create fragments in order to make selection sets more reusable:
# Only most used selection properties
fragment UserDetails on User {
id,
username
}
Then you could query all user details by:
FetchUsers {
users() {
...UserDetails
}
}
You can also add additional fields alongside your fragment:
FetchUserById($id: ID!) {
users(id: $id) {
...UserDetails
count
}
}
Package graphql-type-json supports custom-scalars type JSON.
Use it can show all the field of your json objects.
Here is the link of the example in ApolloGraphql Server.
https://www.apollographql.com/docs/apollo-server/schema/scalars-enums/#custom-scalars
I have a GraphQL query called myAccounts which returns an array of accounts. When I go to the Playground and call the query:
{
accounts {
email
}
}
I get this result:
"data": {
"accounts": [
{
"email": "zach#email-one.com",
},
{
"email": "zach#email-two.com",
}
]
}
However, when I am in my Component, vue-apollo returns two items in the array, but seems to overwrite the second item with the first. Here is the query (in MyAccounts.gql):
query myAccounts {
accounts: myAccounts {
email
}
}
and here is the Apollo query in the component:
import MY_ACCOUNTS_QUERY from '~/apollo/queries/MyAccounts'
...
apollo: {
accounts: {
query: MY_ACCOUNTS_QUERY,
result(data) {
console.log(JSON.stringify(data))
}
}
}
and here is what vue-apollo logs out through the result:
{
"data":{
"accounts":[
{
"email":"zach#email-one.com",
"__typename":"Account"
},
{
"email":"zach#email-one.com",
"__typename":"Account"
}
]
},
"loading":false,
"networkStatus":7,
"stale":false
}
Expected behavior
I would expect the data returned in the Playground to be identical to what vue-apollo is fetching.
Versions
vue: 2.6.10
vue-apollo: #nuxtjs/apollo: 4.0.0-rc18
Additional context
I thought the result hook would be the best way to debug, but any other suggestions gladly welcomed. I assumed that this was a bug in our code, but I cannot figure out what could be causing the repetition (and mismatch).
Apollo normalizes its cache based on the __typename and the id (or _id) field. You need to include an id or _id field in your selection set alongside email. Failing to do so results in both objects being assigned the same key. If you don't have an id field to request, you'll need to provide a custom dataIdFromObject function as shown here.
From Guillaume Chau (https://github.com/Akryum):
This is because the Apollo Client cache can't compute a different ID
for the two items, so you endup with Account:undefined (or similar)
for both. Open the Apollo devtools and look at the myAccounts key in
the cache.
Learn more:
https://www.apollographql.com/docs/react/caching/cache-configuration/
Assume you have a GraphQL type and it includes many fields.
How to query all the fields without writing down a long query that includes the names of all the fields?
For example, If I have these fields :
public function fields()
{
return [
'id' => [
'type' => Type::nonNull(Type::string()),
'description' => 'The id of the user'
],
'username' => [
'type' => Type::string(),
'description' => 'The email of user'
],
'count' => [
'type' => Type::int(),
'description' => 'login count for the user'
]
];
}
To query all the fields usually the query is something like this:
FetchUsers{users(id:"2"){id,username,count}}
But I want a way to have the same results without writing all the fields, something like this:
FetchUsers{users(id:"2"){*}}
//or
FetchUsers{users(id:"2")}
Is there a way to do this in GraphQL ??
I'm using Folkloreatelier/laravel-graphql library.
Unfortunately what you'd like to do is not possible. GraphQL requires you to be explicit about specifying which fields you would like returned from your query.
Yes, you can do this using introspection. Make a GraphQL query like (for type UserType)
{
__type(name:"UserType") {
fields {
name
description
}
}
}
and you'll get a response like (actual field names will depend on your actual schema/type definition)
{
"data": {
"__type": {
"fields": [
{
"name": "id",
"description": ""
},
{
"name": "username",
"description": "Required. 150 characters or fewer. Letters, digits, and #/./+/-/_ only."
},
{
"name": "firstName",
"description": ""
},
{
"name": "lastName",
"description": ""
},
{
"name": "email",
"description": ""
},
( etc. etc. ...)
]
}
}
}
You can then read this list of fields in your client and dynamically build a second GraphQL query to get the values of these fields.
This relies on you knowing the name of the type that you want to get the fields for -- if you don't know the type, you could get all the types and fields together using introspection like
{
__schema {
types {
name
fields {
name
description
}
}
}
}
NOTE: This is the over-the-wire GraphQL data -- you're on your own to figure out how to read and write with your actual client. Your GraphQL javascript library may already employ introspection in some capacity. For example, the apollo codegen command uses introspection to generate types.
2022 Update
Since this answer was originally written, it is now a recommended security practice to TURN OFF introspection in production. Reference: Why you should disable GraphQL introspection in production.
For an environment where introspection is off in production, you could use it in development as a way to assist in creating a static query that was used in production; you wouldn't actually be able to create a query dynamically in production.
I guess the only way to do this is by utilizing reusable fragments:
fragment UserFragment on Users {
id
username
count
}
FetchUsers {
users(id: "2") {
...UserFragment
}
}
I faced this same issue when I needed to load location data that I had serialized into the database from the google places API. Generally I would want the whole thing so it works with maps but I didn't want to have to specify all of the fields every time.
I was working in Ruby so I can't give you the PHP implementation but the principle should be the same.
I defined a custom scalar type called JSON which just returns a literal JSON object.
The ruby implementation was like so (using graphql-ruby)
module Graph
module Types
JsonType = GraphQL::ScalarType.define do
name "JSON"
coerce_input -> (x) { x }
coerce_result -> (x) { x }
end
end
end
Then I used it for our objects like so
field :location, Types::JsonType
I would use this very sparingly though, using it only where you know you always need the whole JSON object (as I did in my case). Otherwise it is defeating the object of GraphQL more generally speaking.
GraphQL query format was designed in order to allow:
Both query and result shape be exactly the same.
The server knows exactly the requested fields, thus the client downloads only essential data.
However, according to GraphQL documentation, you may create fragments in order to make selection sets more reusable:
# Only most used selection properties
fragment UserDetails on User {
id,
username
}
Then you could query all user details by:
FetchUsers {
users() {
...UserDetails
}
}
You can also add additional fields alongside your fragment:
FetchUserById($id: ID!) {
users(id: $id) {
...UserDetails
count
}
}
Package graphql-type-json supports custom-scalars type JSON.
Use it can show all the field of your json objects.
Here is the link of the example in ApolloGraphql Server.
https://www.apollographql.com/docs/apollo-server/schema/scalars-enums/#custom-scalars
I cannot get a WHERE statement working with an 'OR' condition in Strapi via graphql playground.
I would like to return all results where either the 'title' OR 'content' fields contain the search_text.
I have tried the following:
articles(where: {
or: [
{"title_contains" : "search_text"},
{"content_contains" : "search_text"}
]
}) {
title
content
}
but an error is returned.
ERROR: "Your filters contain a field 'or' that doesnt appear on your model definition nor it's relations.
Some statements that work (but not what I am after):
where: { "title_contains" : "sometext" }
working, but behaves as an 'AND'
where: {
"title_contains" : "search_text",
"content_contains" : "search_text"
}
As of July it's possible to do it like this
(where: { _or: [{ someField: "1" }, { someField2: "2" }] })
The workaround here is to create a custom Query and make a custom database query that matches your need.
Here is how to create a custom GraphQL query:
https://strapi.io/documentation/3.0.0-beta.x/guides/graphql.html#example-2
To access the data model, you will have to use strapi.models.article (For an Article model) and inside this variable, you will access to native Mongoose or Bookshelf function. So you will be able to query with an OR
I'm need help passing arguments to collections/connections/arrays in GraphQL syntax.
I'm just learning it, playing with the SWAPI at http://graphql.org/swapi-graphql/
I can pass an id argument to a single type, like this:
query getANewHope {
film(id: "ZmlsbXM6MQ==") {
id
title
}
}
But I don't know how to query the results of a collection/connection
query starships {
allStarships(id: "c3RhcnNoaXBzOjI=") { # this doesn't work
edges {
node(id: "c3RhcnNoaXBzOjI=") { # ...nor this.
id
}
}
}
}
I want to query collections because, I'd like to connect the two ideas like "All Starfighter type ships in A New Hope"?
query filmStarships {
film(id: "ZmlsbXM6MQ==") {
title
starshipConnection { #How to limit this? I can't use (starshipClass: "Starfighter") here...
edges {
node { # ...nor here..
starshipClass # ...nor here.
}
}
}
}
}
query starships2 {
starship (id: "c3RhcnNoaXBzOjI=") { # This doesn't work either
id # even without an arugment abovce, it says "Unknown argument \"id\" on field \"node\" of type \"StarshipsEdge\"."
}
}
Arguments like you're asking for have to be implemented in the schema. The SWAPI does does not expose an argument to filter by starshipClass. Click Docs on the top right of the GraphiQL window to explore the provided schema.
If you are implementing your own schema it would be very easy to add a filter on starshipClass in the resolvers.