Apollo GraphQL kubernetes controller

This controller manages the Apollo GraphQL router. The controller can lookup SubGraph resources and compose a SuperGraphSchema using rover. A router can be deployed using a SuperGraph which uses a composed SuperGraphSchema.

Beta API notice

For v0.x releases and beta api we try not to break the API specs. However in rare cases backports happen to fix major issues.

Example

Define some sub graphs:

apiVersion: apollo.infra.doodle.com/v1beta1
kind: SubGraph
metadata:
  name: products
spec:
  endpoint: http://product-service/graphql
  schema:
    sdl: |
      extend schema
        @link(url: "https://specs.apollo.dev/federation/v2.0", import: ["@key", "@tag"])

      type Query {
        products: [Product!]!
        product(id: ID!): Product
      }

      type Product @key(fields: "id") {
        id: ID!
        name: String!
        price: Float!
      }
---
apiVersion: apollo.infra.doodle.com/v1beta1
kind: SubGraph
metadata:
  name: users
spec:
  endpoint: http://user-server/graphql
  schema:
    sdl: |
      extend schema
        @link(url: "https://specs.apollo.dev/federation/v2.0", import: ["@key", "@tag"])

      type Query {
        users: [User!]!
        user(id: ID!): User
      }

      type User @key(fields: "id") {
        id: ID!
        username: String!
      }

By defining a SuperGraphSchema the controller will compose a schema which again can be used by the router:

apiVersion: apollo.infra.doodle.com/v1beta1
kind: SuperGraphSchema
metadata:
  name: root-schema
spec:
  subGraphSelector:
    matchLabels: {}

If no subGraph selector on the schema is configured no sub graphs will be included. matchLabels: {} will include all of them in the same namespace as the schema. By using match labels or expressions it can be configured what sub graphs should be included.

Similar to the subGraphSelector it is possible to match sub graphs cross namespace by using spec.namespaceSelector. By default a SuperGraphSchema only looks up sub graphs from the same namespace but with a namespace selector this behaviour can be changed. Using namespaceSelector.matchLabels: {} will lookup sub graphs across all namespaces.

IMPORTANT: The apollo-controller uses doodlescheduling/rover as image for the apollo rover cli since the is no official one. rover requires you as a user to accept the license, by design we do not package this acknowledgment. You will need agree to the license via the reconciler template as follow or package your own rover image.

apiVersion: apollo.infra.doodle.com/v1beta1
kind: SuperGraphSchema
metadata:
  name: root-schema
spec:
  subGraphSelector:
    matchLabels: {}
  reconcilerTemplate:
    metadata:
      namespace: controller-namespace
    spec:
      containers:
      - name: rover
        env:
        - name: APOLLO_ELV2_LICENSE
          value: accept

Deploy a router:

apiVersion: apollo.infra.doodle.com/v1beta1
kind: SuperGraph
metadata:
  name: entrypoint
spec:
  schema:
    name: root-schema
  routerConfig: {}

Router deployment template

It is possible to define a custom apollo deployment template which the controller will use to spin up the managed deployment. In the following example the deployment receives an additional container called mysidecar. Also resources are declared for the router container.

Note: The apollo router container is always called router. It is possible to patch that container by using said name as in the example bellow.

apiVersion: apollo.infra.doodle.com/v1beta1
kind: SuperGraph
metadata:
  name: entrypoint
spec:
  schema:
    name: root-schema
  deploymentTemplate:
    spec:
      template:
        replicas: 3
        spec:
          containers:
          - name: router
            resources:
              requests:
                memory: 256Mi
                cpu: 50m
              limits:
                memory: 512Mi
          - name: random-sidecar
            image: mysidecar

SuperGraphSchema rover reconciler template

The super graph schema composer emits a custom rover reconciler pod which composes the super graph config. The reconciler pod can be customized:

apiVersion: apollo.infra.doodle.com/v1beta1
kind: SuperGraphSchema
metadata:
  name: root-schema
spec:
  subGraphSelector:
    matchLabels: {}
  reconcilerTemplate:
    spec:
      containers:
      - name: rover
        resources:
          request:
            memory: 24Mi
            cpu: 50m
          limit:
            memory: 24Mi

Suspend/Resume reconciliation

The reconciliation can be paused by setting spec.suspend to true:

kubectl patch SuperGraph default-p '{"spec":{"suspend": true}}' --type=merge

Observe SuperGraph reconciliation

A SuperGraph will have all discovered resources populated in .status.subResourceCatalog. Also there are two conditions which are useful for observing Ready and a temporary one named Reconciling as long as a reconciliation is in progress.

Installation

Helm

Please see chart/apollo-controller for the helm chart docs.

Manifests/kustomize

Alternatively you may get the bundled manifests in each release to deploy it using kustomize or use them directly.

Configuration

The controller can be configured using cmd args:

--concurrent int                            The number of concurrent SuperGraph reconciles. (default 4)
--enable-leader-election                    Enable leader election for controller manager. Enabling this will ensure there is only one active controller manager.
--graceful-shutdown-timeout duration        The duration given to the reconciler to finish before forcibly stopping. (default 10m0s)
--health-addr string                        The address the health endpoint binds to. (default ":9557")
--insecure-kubeconfig-exec                  Allow use of the user.exec section in kubeconfigs provided for remote apply.
--insecure-kubeconfig-tls                   Allow that kubeconfigs provided for remote apply can disable TLS verification.
--kube-api-burst int                        The maximum burst queries-per-second of requests sent to the Kubernetes API. (default 300)
--kube-api-qps float32                      The maximum queries-per-second of requests sent to the Kubernetes API. (default 50)
--leader-election-lease-duration duration   Interval at which non-leader candidates will wait to force acquire leadership (duration string). (default 35s)
--leader-election-release-on-cancel         Defines if the leader should step down voluntarily on controller manager shutdown. (default true)
--leader-election-renew-deadline duration   Duration that the leading controller manager will retry refreshing leadership before giving up (duration string). (default 30s)
--leader-election-retry-period duration     Duration the LeaderElector clients should wait between tries of actions (duration string). (default 5s)
--log-encoding string                       Log encoding format. Can be 'json' or 'console'. (default "json")
--log-level string                          Log verbosity level. Can be one of 'trace', 'debug', 'info', 'error'. (default "info")
--max-retry-delay duration                  The maximum amount of time for which an object being reconciled will have to wait before a retry. (default 15m0s)
--metrics-addr string                       The address the metric endpoint binds to. (default ":9556")
--min-retry-delay duration                  The minimum amount of time for which an object being reconciled will have to wait before a retry. (default 750ms)
--watch-all-namespaces                      Watch for resources in all namespaces, if set to false it will only watch the runtime namespace. (default true)
--watch-label-selector string               Watch for resources with matching labels e.g. 'sharding.fluxcd.io/shard=shard1'.