debian-mirror-gitlab/doc/architecture/blueprints/pods/pods-feature-graphql.md
2023-01-12 18:35:48 +00:00

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---
stage: enablement
group: pods
comments: false
description: 'Pods: GraphQL'
---
DISCLAIMER:
This page may contain information related to upcoming products, features and
functionality. It is important to note that the information presented is for
informational purposes only, so please do not rely on the information for
purchasing or planning purposes. Just like with all projects, the items
mentioned on the page are subject to change or delay, and the development,
release, and timing of any products, features, or functionality remain at the
sole discretion of GitLab Inc.
This document is a work-in-progress and represents a very early state of the
Pods design. Significant aspects are not documented, though we expect to add
them in the future. This is one possible architecture for Pods, and we intend to
contrast this with alternatives before deciding which approach to implement.
This documentation will be kept even if we decide not to implement this so that
we can document the reasons for not choosing this approach.
# Pods: GraphQL
GitLab exensively uses GraphQL to perform efficient data query operations.
GraphQL due to it's nature is not directly routable. The way how GitLab uses
it calls the `/api/graphql` endpoint, and only query or mutation of body request
might define where the data can be accessed.
## 1. Definition
## 2. Data flow
## 3. Proposal
There are at least two main ways to implement GraphQL in Pods architecture.
### 3.1. GraphQL routable by endpoint
Change `/api/graphql` to `/api/organization/<organization>/graphql`.
- This breaks all existing usages of `/api/graphql` endpoint
since the API URI is changed.
### 3.2. GraphQL routable by body
As part of router parse GraphQL body to find a routable entity, like `project`.
- This still makes the GraphQL query be executed only in context of a given Pod
and not allowing the data to be merged.
```json
# Good example
{
project(fullPath:"gitlab-org/gitlab") {
id
description
}
}
# Bad example, since Merge Request is not routable
{
mergeRequest(id: 1111) {
iid
description
}
}
```
### 3.3. Merging GraphQL Proxy
Implement as part of router GraphQL Proxy which can parse body
and merge results from many Pods.
- This might make pagination hard to achieve, or we might assume that
we execute many queries of which results are merged across all Pods.
```json
{
project(fullPath:"gitlab-org/gitlab"){
id, description
}
group(fullPath:"gitlab-com") {
id, description
}
}
```
## 4. Evaluation
## 4.1. Pros
## 4.2. Cons