[feature] Implement `/api/v2/instance` endpoint (#1409)

* interim: start adding /api/v2/instance

* finish up

1 files changed, 117 insertions, 0 deletions

diff --git a/internal/api/model/instancev1.go b/internal/api/model/instancev1.go
new file mode 100644
index 000000000..291b3f34b
--- /dev/null
+++ b/internal/api/model/instancev1.go
@@ -0,0 +1,117 @@
+/*
+   GoToSocial
+   Copyright (C) 2021-2023 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package model
+
+// InstanceV1 models information about this instance.
+//
+// swagger:model instanceV1
+type InstanceV1 struct {
+	// The URI of the instance.
+	// example: https://gts.example.org
+	URI string `json:"uri,omitempty"`
+	// The domain of accounts on this instance.
+	// This will not necessarily be the same as
+	// simply the Host part of the URI.
+	// example: example.org
+	AccountDomain string `json:"account_domain,omitempty"`
+	// The title of the instance.
+	// example: GoToSocial Example Instance
+	Title string `json:"title,omitempty"`
+	// Description of the instance.
+	//
+	// Should be HTML formatted, but might be plaintext.
+	//
+	// This should be displayed on the 'about' page for an instance.
+	Description string `json:"description"`
+	// A shorter description of the instance.
+	//
+	// Should be HTML formatted, but might be plaintext.
+	//
+	// This should be displayed on the instance splash/landing page.
+	ShortDescription string `json:"short_description"`
+	// An email address that may be used for inquiries.
+	// example: admin@example.org
+	Email string `json:"email"`
+	// The version of GoToSocial installed on the instance.
+	//
+	// This will contain at least a semantic version number.
+	//
+	// It may also contain, after a space, the short git commit ID of the running software.
+	//
+	// example: 0.1.1 cb85f65
+	Version string `json:"version"`
+	// Primary language of the instance.
+	// example: en
+	Languages []string `json:"languages,omitempty"`
+	// New account registrations are enabled on this instance.
+	Registrations bool `json:"registrations"`
+	// New account registrations require admin approval.
+	ApprovalRequired bool `json:"approval_required"`
+	// Invites are enabled on this instance.
+	InvitesEnabled bool `json:"invites_enabled"`
+	// Configuration object containing values about status limits etc.
+	// This key/value will be omitted for remote instances.
+	Configuration InstanceV1Configuration `json:"configuration,omitempty"`
+	// URLs of interest for client applications.
+	URLs InstanceV1URLs `json:"urls,omitempty"`
+	// Statistics about the instance: number of posts, accounts, etc.
+	Stats map[string]int `json:"stats,omitempty"`
+	// URL of the instance avatar/banner image.
+	// example: https://example.org/files/instance/thumbnail.jpeg
+	Thumbnail string `json:"thumbnail"`
+	// MIME type of the instance thumbnail.
+	// example: image/png
+	ThumbnailType string `json:"thumbnail_type,omitempty"`
+	// Description of the instance thumbnail.
+	// example: picture of a cute lil' friendly sloth
+	ThumbnailDescription string `json:"thumbnail_description,omitempty"`
+	// Contact account for the instance.
+	ContactAccount *Account `json:"contact_account,omitempty"`
+	// Maximum allowed length of a post on this instance, in characters.
+	//
+	// This is provided for compatibility with Tusky and other apps.
+	//
+	// example: 5000
+	MaxTootChars uint `json:"max_toot_chars"`
+}
+
+// InstanceV1URLs models instance-relevant URLs for client application consumption.
+//
+// swagger:model instanceV1URLs
+type InstanceV1URLs struct {
+	// Websockets address for status and notification streaming.
+	// example: wss://example.org
+	StreamingAPI string `json:"streaming_api"`
+}
+
+// InstanceV1Configuration models instance configuration parameters.
+//
+// swagger:model instanceV1Configuration
+type InstanceV1Configuration struct {
+	// Instance configuration pertaining to status limits.
+	Statuses InstanceConfigurationStatuses `json:"statuses"`
+	// Instance configuration pertaining to media attachment types + size limits.
+	MediaAttachments InstanceConfigurationMediaAttachments `json:"media_attachments"`
+	// Instance configuration pertaining to poll limits.
+	Polls InstanceConfigurationPolls `json:"polls"`
+	// Instance configuration pertaining to accounts.
+	Accounts InstanceConfigurationAccounts `json:"accounts"`
+	// Instance configuration pertaining to emojis.
+	Emojis InstanceConfigurationEmojis `json:"emojis"`
+}