[feature] Status source endpoint (#2848)

* [feature] statusSource endpoint

* finish up

7 files changed, 320 insertions, 0 deletions

diff --git a/docs/api/swagger.yaml b/docs/api/swagger.yaml
index 18c22a980..7fb3efe76 100644
--- a/docs/api/swagger.yaml
+++ b/docs/api/swagger.yaml
@@ -2399,6 +2399,27 @@ definitions:
         type: object
         x-go-name: StatusReblogged
         x-go-package: github.com/superseriousbusiness/gotosocial/internal/api/model
+    statusSource:
+        description: |-
+            StatusSource represents the source text of a
+            status as submitted to the API when it was created.
+        properties:
+            id:
+                description: ID of the status.
+                example: 01FBVD42CQ3ZEEVMW180SBX03B
+                type: string
+                x-go-name: ID
+            source:
+                description: Plain-text source of a status.
+                type: string
+                x-go-name: Text
+            spoiler_text:
+                description: Plain-text version of spoiler text.
+                type: string
+                x-go-name: SpoilerText
+        type: object
+        x-go-name: StatusSource
+        x-go-package: github.com/superseriousbusiness/gotosocial/internal/api/model
     swaggerCollection:
         properties:
             '@context':
@@ -7693,6 +7714,42 @@ paths:
             summary: View accounts that have reblogged/boosted the target status.
             tags:
                 - statuses
+    /api/v1/statuses/{id}/source:
+        get:
+            operationId: statusSourceGet
+            parameters:
+                - description: Target status ID.
+                  in: path
+                  name: id
+                  required: true
+                  type: string
+            produces:
+                - application/json
+            responses:
+                "200":
+                    description: ""
+                    schema:
+                        items:
+                            $ref: '#/definitions/statusSource'
+                        type: array
+                "400":
+                    description: bad request
+                "401":
+                    description: unauthorized
+                "403":
+                    description: forbidden
+                "404":
+                    description: not found
+                "406":
+                    description: not acceptable
+                "500":
+                    description: internal server error
+            security:
+                - OAuth2 Bearer:
+                    - read:statuses
+            summary: View source text of status with the given ID. Requester must own the status.
+            tags:
+                - statuses
     /api/v1/statuses/{id}/unbookmark:
         post:
             operationId: statusUnbookmark
diff --git a/internal/api/client/statuses/status.go b/internal/api/client/statuses/status.go
index 266481b91..33af9c456 100644
--- a/internal/api/client/statuses/status.go
+++ b/internal/api/client/statuses/status.go
@@ -67,6 +67,9 @@ const (
 
 	// HistoryPath is used for fetching history of posts.
 	HistoryPath = BasePathWithID + "/history"
+
+	// SourcePath is used for fetching source of a post.
+	SourcePath = BasePathWithID + "/source"
 )
 
 type Module struct {
@@ -110,4 +113,5 @@ func (m *Module) Route(attachHandler func(method string, path string, f ...gin.H
 
 	// history/edit stuff
 	attachHandler(http.MethodGet, HistoryPath, m.StatusHistoryGETHandler)
+	attachHandler(http.MethodGet, SourcePath, m.StatusSourceGETHandler)
 }
diff --git a/internal/api/client/statuses/statussource.go b/internal/api/client/statuses/statussource.go
new file mode 100644
index 000000000..c74d99bfc
--- /dev/null
+++ b/internal/api/client/statuses/statussource.go
@@ -0,0 +1,95 @@
+// GoToSocial
+// Copyright (C) GoToSocial Authors admin@gotosocial.org
+// SPDX-License-Identifier: AGPL-3.0-or-later
+//
+// 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 statuses
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	apiutil "github.com/superseriousbusiness/gotosocial/internal/api/util"
+	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
+	"github.com/superseriousbusiness/gotosocial/internal/oauth"
+)
+
+// StatusSourceGETHandler swagger:operation GET /api/v1/statuses/{id}/source statusSourceGet
+//
+// View source text of status with the given ID. Requester must own the status.
+//
+//	---
+//	tags:
+//	- statuses
+//
+//	produces:
+//	- application/json
+//
+//	parameters:
+//	-
+//		name: id
+//		type: string
+//		description: Target status ID.
+//		in: path
+//		required: true
+//
+//	security:
+//	- OAuth2 Bearer:
+//		- read:statuses
+//
+//	responses:
+//		'200':
+//			schema:
+//				type: array
+//				items:
+//					"$ref": "#/definitions/statusSource"
+//		'400':
+//			description: bad request
+//		'401':
+//			description: unauthorized
+//		'403':
+//			description: forbidden
+//		'404':
+//			description: not found
+//		'406':
+//			description: not acceptable
+//		'500':
+//			description: internal server error
+func (m *Module) StatusSourceGETHandler(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.InstanceGetV1)
+		return
+	}
+
+	if _, err := apiutil.NegotiateAccept(c, apiutil.JSONAcceptHeaders...); err != nil {
+		apiutil.ErrorHandler(c, gtserror.NewErrorNotAcceptable(err, err.Error()), m.processor.InstanceGetV1)
+		return
+	}
+
+	targetStatusID, errWithCode := apiutil.ParseID(c.Param(IDKey))
+	if errWithCode != nil {
+		apiutil.ErrorHandler(c, errWithCode, m.processor.InstanceGetV1)
+		return
+	}
+
+	resp, errWithCode := m.processor.Status().SourceGet(c.Request.Context(), authed.Account, targetStatusID)
+	if errWithCode != nil {
+		apiutil.ErrorHandler(c, errWithCode, m.processor.InstanceGetV1)
+		return
+	}
+
+	c.JSON(http.StatusOK, resp)
+}
diff --git a/internal/api/client/statuses/statussource_test.go b/internal/api/client/statuses/statussource_test.go
new file mode 100644
index 000000000..edb2dad3c
--- /dev/null
+++ b/internal/api/client/statuses/statussource_test.go
@@ -0,0 +1,101 @@
+// GoToSocial
+// Copyright (C) GoToSocial Authors admin@gotosocial.org
+// SPDX-License-Identifier: AGPL-3.0-or-later
+//
+// 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 statuses_test
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/suite"
+	"github.com/superseriousbusiness/gotosocial/internal/api/client/statuses"
+	"github.com/superseriousbusiness/gotosocial/internal/oauth"
+	"github.com/superseriousbusiness/gotosocial/testrig"
+)
+
+type StatusSourceTestSuite struct {
+	StatusStandardTestSuite
+}
+
+func (suite *StatusSourceTestSuite) TestGetSource() {
+	var (
+		testApplication = suite.testApplications["application_1"]
+		testAccount     = suite.testAccounts["local_account_1"]
+		testUser        = suite.testUsers["local_account_1"]
+		testToken       = oauth.DBTokenToToken(suite.testTokens["local_account_1"])
+		targetStatusID  = suite.testStatuses["local_account_1_status_1"].ID
+		target          = fmt.Sprintf("http://localhost:8080%s", strings.ReplaceAll(statuses.SourcePath, ":id", targetStatusID))
+	)
+
+	// Setup request.
+	recorder := httptest.NewRecorder()
+	request := httptest.NewRequest(http.MethodGet, target, nil)
+	request.Header.Set("accept", "application/json")
+	ctx, _ := testrig.CreateGinTestContext(recorder, request)
+
+	// Set auth + path params.
+	ctx.Set(oauth.SessionAuthorizedApplication, testApplication)
+	ctx.Set(oauth.SessionAuthorizedToken, testToken)
+	ctx.Set(oauth.SessionAuthorizedUser, testUser)
+	ctx.Set(oauth.SessionAuthorizedAccount, testAccount)
+	ctx.Params = gin.Params{
+		gin.Param{
+			Key:   statuses.IDKey,
+			Value: targetStatusID,
+		},
+	}
+
+	// Call the handler.
+	suite.statusModule.StatusSourceGETHandler(ctx)
+
+	// Check code.
+	if code := recorder.Code; code != http.StatusOK {
+		suite.FailNow("", "unexpected http code: %d", code)
+	}
+
+	// Read body.
+	result := recorder.Result()
+	defer result.Body.Close()
+
+	b, err := io.ReadAll(result.Body)
+	if err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	// Indent nicely.
+	dst := new(bytes.Buffer)
+	if err := json.Indent(dst, b, "", "  "); err != nil {
+		suite.FailNow(err.Error())
+	}
+
+	suite.Equal(`{
+  "id": "01F8MHAMCHF6Y650WCRSCP4WMY",
+  "source": "hello everyone!",
+  "spoiler_text": "introduction post"
+}`, dst.String())
+}
+
+func TestStatusSourceTestSuite(t *testing.T) {
+	suite.Run(t, new(StatusSourceTestSuite))
+}
diff --git a/internal/api/model/status.go b/internal/api/model/status.go
index e8677ff6b..d7d3266ed 100644
--- a/internal/api/model/status.go
+++ b/internal/api/model/status.go
@@ -250,6 +250,20 @@ const (
 	StatusContentTypeDefault                    = StatusContentTypePlain
 )
 
+// StatusSource represents the source text of a
+// status as submitted to the API when it was created.
+//
+// swagger:model statusSource
+type StatusSource struct {
+	// ID of the status.
+	// example: 01FBVD42CQ3ZEEVMW180SBX03B
+	ID string `json:"id"`
+	// Plain-text source of a status.
+	Text string `json:"source"`
+	// Plain-text version of spoiler text.
+	SpoilerText string `json:"spoiler_text"`
+}
+
 // StatusEdit represents one historical revision of a status, containing
 // partial information about the state of the status at that revision.
 //
diff --git a/internal/processing/status/get.go b/internal/processing/status/get.go
index 8b0c21adf..57fd4005c 100644
--- a/internal/processing/status/get.go
+++ b/internal/processing/status/get.go
@@ -73,6 +73,44 @@ func (p *Processor) Get(ctx context.Context, requestingAccount *gtsmodel.Account
 	return p.c.GetAPIStatus(ctx, requestingAccount, targetStatus)
 }
 
+// SourceGet returns the *apimodel.StatusSource version of the targetStatusID.
+// Status must belong to the requester, and must not be a boost.
+func (p *Processor) SourceGet(ctx context.Context, requestingAccount *gtsmodel.Account, targetStatusID string) (*apimodel.StatusSource, gtserror.WithCode) {
+	targetStatus, errWithCode := p.c.GetVisibleTargetStatus(ctx,
+		requestingAccount,
+		targetStatusID,
+		nil, // default freshness
+	)
+	if errWithCode != nil {
+		return nil, errWithCode
+	}
+
+	// Redirect to wrapped status if boost.
+	targetStatus, errWithCode = p.c.UnwrapIfBoost(
+		ctx,
+		requestingAccount,
+		targetStatus,
+	)
+	if errWithCode != nil {
+		return nil, errWithCode
+	}
+
+	if targetStatus.AccountID != requestingAccount.ID {
+		err := gtserror.Newf(
+			"status %s does not belong to account %s",
+			targetStatusID, requestingAccount.ID,
+		)
+		return nil, gtserror.NewErrorNotFound(err)
+	}
+
+	statusSource, err := p.converter.StatusToAPIStatusSource(ctx, targetStatus)
+	if err != nil {
+		err = gtserror.Newf("error converting status: %w", err)
+		return nil, gtserror.NewErrorInternalError(err)
+	}
+	return statusSource, nil
+}
+
 // WebGet gets the given status for web use, taking account of privacy settings.
 func (p *Processor) WebGet(ctx context.Context, targetStatusID string) (*apimodel.Status, gtserror.WithCode) {
 	targetStatus, errWithCode := p.c.GetVisibleTargetStatus(ctx,
diff --git a/internal/typeutils/internaltofrontend.go b/internal/typeutils/internaltofrontend.go
index fa704a5bb..98e1a4611 100644
--- a/internal/typeutils/internaltofrontend.go
+++ b/internal/typeutils/internaltofrontend.go
@@ -792,6 +792,17 @@ func (c *Converter) StatusToWebStatus(
 	return webStatus, nil
 }
 
+// StatusToAPIStatusSource returns the *apimodel.StatusSource of the given status.
+// Callers should check beforehand whether a requester has permission to view the
+// source of the status, and ensure they're passing only a local status into this function.
+func (c *Converter) StatusToAPIStatusSource(ctx context.Context, s *gtsmodel.Status) (*apimodel.StatusSource, error) {
+	return &apimodel.StatusSource{
+		ID:          s.ID,
+		Text:        s.Text,
+		SpoilerText: s.ContentWarning,
+	}, nil
+}
+
 // statusToFrontend is a package internal function for
 // parsing a status into its initial frontend representation.
 //