[chore] The Big Middleware and API Refactor (tm) (#1250)

* interim commit: start refactoring middlewares into package under router

* another interim commit, this is becoming a big job

* another fucking massive interim commit

* refactor bookmarks to new style

* ambassador, wiz zeze commits you are spoiling uz

* she compiles, we're getting there

* we're just normal men; we're just innocent men

* apiutil

* whoopsie

* i'm glad noone reads commit msgs haha :blob_sweat:

* use that weirdo go-bytesize library for maxMultipartMemory

* fix media module paths

internal/api/client/accounts/relationships.go

@@ -0,0 +1,93 @@
+package accounts
+
+import (
+	"errors"
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
+	apiutil "github.com/superseriousbusiness/gotosocial/internal/api/util"
+	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
+	"github.com/superseriousbusiness/gotosocial/internal/oauth"
+)
+
+// AccountRelationshipsGETHandler swagger:operation GET /api/v1/accounts/relationships accountRelationships
+//
+// See your account's relationships with the given account IDs.
+//
+//	---
+//	tags:
+//	- accounts
+//
+//	produces:
+//	- application/json
+//
+//	parameters:
+//	-
+//		name: id
+//		type: array
+//		items:
+//			type: string
+//		description: Account IDs.
+//		in: query
+//		required: true
+//
+//	security:
+//	- OAuth2 Bearer:
+//		- read:accounts
+//
+//	responses:
+//		'200':
+//			name: account relationships
+//			description: Array of account relationships.
+//			schema:
+//				type: array
+//				items:
+//					"$ref": "#/definitions/accountRelationship"
+//		'400':
+//			description: bad request
+//		'401':
+//			description: unauthorized
+//		'404':
+//			description: not found
+//		'406':
+//			description: not acceptable
+//		'500':
+//			description: internal server error
+func (m *Module) AccountRelationshipsGETHandler(c *gin.Context) {
+	authed, err := oauth.Authed(c, true, true, true, true)
+	if err != nil {
+		apiutil.ErrorHandler(c, gtserror.NewErrorUnauthorized(err, err.Error()), m.processor.InstanceGet)
+		return
+	}
+
+	if _, err := apiutil.NegotiateAccept(c, apiutil.JSONAcceptHeaders...); err != nil {
+		apiutil.ErrorHandler(c, gtserror.NewErrorNotAcceptable(err, err.Error()), m.processor.InstanceGet)
+		return
+	}
+
+	targetAccountIDs := c.QueryArray("id[]")
+	if len(targetAccountIDs) == 0 {
+		// check fallback -- let's be generous and see if maybe it's just set as 'id'?
+		id := c.Query("id")
+		if id == "" {
+			err = errors.New("no account id(s) specified in query")
+			apiutil.ErrorHandler(c, gtserror.NewErrorBadRequest(err, err.Error()), m.processor.InstanceGet)
+			return
+		}
+		targetAccountIDs = append(targetAccountIDs, id)
+	}
+
+	relationships := []apimodel.Relationship{}
+
+	for _, targetAccountID := range targetAccountIDs {
+		r, errWithCode := m.processor.AccountRelationshipGet(c.Request.Context(), authed, targetAccountID)
+		if errWithCode != nil {
+			apiutil.ErrorHandler(c, errWithCode, m.processor.InstanceGet)
+			return
+		}
+		relationships = append(relationships, *r)
+	}
+
+	c.JSON(http.StatusOK, relationships)
+}