GraphQL
Since Camel 3.0
Only producer is supported
The GraphQL component is a GraphQL client that communicates over HTTP and supports queries and mutations, but not subscriptions. It uses the Apache HttpClient library.
Maven users will need to add the following dependency to their pom.xml
for this component:
<dependency>
<groupId>org.apache.camel</groupId>
<artifactId>camel-graphql</artifactId>
<version>x.x.x</version>
<!-- use the same version as your Camel core version -->
</dependency>
GraphQL Endpoint URI
The GraphQL endpoint is configured using URI syntax:
graphql:httpUri
with the following path and query parameters:
Path Parameters (1 parameters):
Name | Description | Default | Type |
---|---|---|---|
httpUri |
Required The GraphQL server URI. |
URI |
Query Parameters (11 parameters):
Name | Description | Default | Type |
---|---|---|---|
lazyStartProducer (producer) |
Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. |
false |
boolean |
operationName (producer) |
The query or mutation name. |
String |
|
proxyHost (producer) |
The proxy host in the format hostname:port. |
String |
|
query (producer) |
The query text. |
String |
|
queryFile (producer) |
The query file name located in the classpath. |
String |
|
variables (producer) |
The JsonObject instance containing the operation variables. |
JsonObject |
|
synchronous (advanced) |
Sets whether synchronous processing should be strictly used, or Camel is allowed to use asynchronous processing (if supported). |
false |
boolean |
accessToken (security) |
The access token sent in the Authorization header. |
String |
|
jwtAuthorizationType (security) |
The JWT Authorization type. Default is Bearer. |
Bearer |
String |
password (security) |
The password for Basic authentication. |
String |
|
username (security) |
The username for Basic authentication. |
String |
GraphQL Component Options
The GraphQL component supports 2 options, which are listed below.
Name | Description | Default | Type |
---|---|---|---|
lazyStartProducer (producer) |
Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. |
false |
boolean |
autowiredEnabled (advanced) |
Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc. |
true |
boolean |
Message Body
Camel will store the GraphQL response from the external server on the OUT message body. All headers from the IN message will be copied to the OUT message, so headers are preserved during routing. Additionally Camel will add the HTTP response headers as well to the OUT message headers.
Examples
Queries
Simple queries can be defined directly in the URI:
from("direct:start")
.to("graphql://http://example.com/graphql?query={books{id name}}")
More complex queries can be stored in a file and referenced in the URI:
# booksQuery.graphql
query Books {
books {
id
name
}
}
from("direct:start")
.to("graphql://http://example.com/graphql?queryFile=booksQuery.graphql")
When the query file defines multiple operations, it’s required to specify which one should be executed:
from("direct:start")
.to("graphql://http://example.com/graphql?queryFile=multipleQueries.graphql&operationName=Books")
Queries with variables need to reference a JsonObject instance from the registry:
@BindToRegistry("bookByIdQueryVariables")
public JsonObject bookByIdQueryVariables() {
JsonObject variables = new JsonObject();
variables.put("id", "book-1");
return variables;
}
from("direct:start")
.to("graphql://http://example.com/graphql?queryFile=bookByIdQuery.graphql&variables=#bookByIdQueryVariables")
Mutations
Mutations are like queries with variables. They specify a query and a reference to a variables bean:
# addBookMutation.graphql
mutation AddBook($bookInput: BookInput) {
addBook(bookInput: $bookInput) {
id
name
author {
name
}
}
}
@BindToRegistry("addBookMutationVariables")
public JsonObject addBookMutationVariables() {
JsonObject bookInput = new JsonObject();
bookInput.put("name", "Typee");
bookInput.put("authorId", "author-2");
JsonObject variables = new JsonObject();
variables.put("bookInput", bookInput);
return variables;
}
from("direct:start")
.to("graphql://http://example.com/graphql?graphql?queryFile=addBookMutation.graphql&variables=#addBookMutationVariables")
Spring Boot Auto-Configuration
When using graphql with Spring Boot make sure to use the following Maven dependency to have support for auto configuration:
<dependency>
<groupId>org.apache.camel.springboot</groupId>
<artifactId>camel-graphql-starter</artifactId>
<version>x.x.x</version>
<!-- use the same version as your Camel core version -->
</dependency>
The component supports 3 options, which are listed below.
Name | Description | Default | Type |
---|---|---|---|
camel.component.graphql.autowired-enabled |
Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc. |
true |
Boolean |
camel.component.graphql.enabled |
Whether to enable auto configuration of the graphql component. This is enabled by default. |
Boolean |
|
camel.component.graphql.lazy-start-producer |
Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing. |
false |
Boolean |