The performance was greatly improved by removing two N+1 queries issues
for each endpoint.
For comparison:
1. `GET /projects/:id/members`
With two N+1 queries issues (one was already fxed in the following
snippet):
```
ProjectMember Load (0.2ms) SELECT "members".* FROM "members" WHERE
"members"."source_type" = $1 AND "members"."type" IN ('ProjectMember')
AND "members"."source_id" = $2 AND "members"."source_type" = $3 AND
"members"."type" IN ('ProjectMember') AND "members"."requested_at" IS
NULL ORDER BY "members"."id" DESC [["source_type", "Project"],
["source_id", 1], ["source_type", "Project"]]
User Load (0.5ms) SELECT "users".* FROM "users" WHERE "users"."id" IN
(5, 22, 16, 13) ORDER BY "users"."id" DESC
ActiveRecord::SchemaMigration Load (0.2ms) SELECT
"schema_migrations".* FROM "schema_migrations"
ProjectMember Load (0.3ms) SELECT "members".* FROM "members" WHERE
"members"."source_type" = $1 AND "members"."type" IN ('ProjectMember')
AND "members"."source_id" = $2 AND "members"."source_type" = $3 AND
"members"."type" IN ('ProjectMember') AND "members"."requested_at" IS
NULL AND "members"."user_id" = $4 ORDER BY "members"."id" DESC LIMIT 1
[["source_type", "Project"], ["source_id", 1], ["source_type",
"Project"], ["user_id", 5]]
ProjectMember Load (0.3ms) SELECT "members".* FROM "members" WHERE
"members"."source_type" = $1 AND "members"."type" IN ('ProjectMember')
AND "members"."source_id" = $2 AND "members"."source_type" = $3 AND
"members"."type" IN ('ProjectMember') AND "members"."requested_at" IS
NULL AND "members"."user_id" = $4 ORDER BY "members"."id" DESC LIMIT 1
[["source_type", "Project"], ["source_id", 1], ["source_type",
"Project"], ["user_id", 22]]
ProjectMember Load (0.3ms) SELECT "members".* FROM "members" WHERE
"members"."source_type" = $1 AND "members"."type" IN ('ProjectMember')
AND "members"."source_id" = $2 AND "members"."source_type" = $3 AND
"members"."type" IN ('ProjectMember') AND "members"."requested_at" IS
NULL AND "members"."user_id" = $4 ORDER BY "members"."id" DESC LIMIT 1
[["source_type", "Project"], ["source_id", 1], ["source_type",
"Project"], ["user_id", 16]]
ProjectMember Load (0.3ms) SELECT "members".* FROM "members" WHERE
"members"."source_type" = $1 AND "members"."type" IN ('ProjectMember')
AND "members"."source_id" = $2 AND "members"."source_type" = $3 AND
"members"."type" IN ('ProjectMember') AND "members"."requested_at" IS
NULL AND "members"."user_id" = $4 ORDER BY "members"."id" DESC LIMIT 1
[["source_type", "Project"], ["source_id", 1], ["source_type",
"Project"], ["user_id", 13]]
```
Without the N+1 queries issues:
```
ProjectMember Load (0.3ms) SELECT "members".* FROM "members" WHERE
"members"."source_type" = $1 AND "members"."type" IN ('ProjectMember')
AND "members"."source_id" = $2 AND "members"."source_type" = $3 AND
"members"."type" IN ('ProjectMember') AND "members"."requested_at" IS
NULL ORDER BY "members"."id" DESC LIMIT 20 OFFSET 0 [["source_type",
"Project"], ["source_id", 1], ["source_type", "Project"]]
User Load (0.5ms) SELECT "users".* FROM "users" WHERE "users"."id" IN
(5, 22, 16, 13) ORDER BY "users"."id" DESC
```
2. `GET /projects/:id/access_requests`
With two N+1 queries issues:
```
ProjectMember Load (0.3ms) SELECT "members".* FROM "members" WHERE
"members"."source_type" = $1 AND "members"."type" IN ('ProjectMember')
AND "members"."source_id" = $2 AND "members"."source_type" = $3 AND
"members"."type" IN ('ProjectMember') AND ("members"."requested_at" IS
NOT NULL) ORDER BY "members"."id" DESC [["source_type", "Project"],
["source_id", 8], ["source_type", "Project"]]
User Load (0.1ms) SELECT "users".* FROM "users" WHERE "users"."id" =
$1 ORDER BY "users"."id" DESC LIMIT 1 [["id", 24]]
User Load (0.1ms) SELECT "users".* FROM "users" WHERE "users"."id" =
$1 ORDER BY "users"."id" DESC LIMIT 1 [["id", 23]]
ActiveRecord::SchemaMigration Load (0.2ms) SELECT
"schema_migrations".* FROM "schema_migrations"
ProjectMember Load (0.1ms) SELECT "members".* FROM "members" WHERE
"members"."source_type" = $1 AND "members"."type" IN ('ProjectMember')
AND "members"."source_id" = $2 AND "members"."source_type" = $3 AND
"members"."type" IN ('ProjectMember') AND ("members"."requested_at" IS
NOT NULL) AND "members"."user_id" = $4 ORDER BY "members"."id" DESC
LIMIT 1 [["source_type", "Project"], ["source_id", 8], ["source_type",
"Project"], ["user_id", 24]]
ProjectMember Load (0.2ms) SELECT "members".* FROM "members" WHERE
"members"."source_type" = $1 AND "members"."type" IN ('ProjectMember')
AND "members"."source_id" = $2 AND "members"."source_type" = $3 AND
"members"."type" IN ('ProjectMember') AND ("members"."requested_at" IS
NOT NULL) AND "members"."user_id" = $4 ORDER BY "members"."id" DESC
LIMIT 1 [["source_type", "Project"], ["source_id", 8], ["source_type",
"Project"], ["user_id", 23]]
```
Without the N+1 queries issues:
```
ProjectMember Load (0.3ms) SELECT "members".* FROM "members" WHERE
"members"."source_type" = $1 AND "members"."type" IN ('ProjectMember')
AND "members"."source_id" = $2 AND "members"."source_type" = $3 AND
"members"."type" IN ('ProjectMember') AND ("members"."requested_at" IS
NOT NULL) ORDER BY "members"."id" DESC LIMIT 20 OFFSET 0
[["source_type", "Project"], ["source_id", 8], ["source_type",
"Project"]]
User Load (0.5ms) SELECT "users".* FROM "users" WHERE "users"."id" IN
(24, 23) ORDER BY "users"."id" DESC
```
Signed-off-by: Rémy Coutable <remy@rymai.me>
Also, mutualize AccessRequests and Members endpoints for Group &
Project.
New API documentation for the AccessRequests endpoints.
Signed-off-by: Rémy Coutable <remy@rymai.me>
