feat(discord): Add API-driven pipeline backend for Discord integration setup

Implement get_pipeline_api_steps() on DiscordIntegrationProvider with a
custom DiscordOAuthApiStep that handles Discord's unique OAuth flow
(bot permissions in authorize URL, guild_id in callback). The step
binds guild_id and code to pipeline state so build_integration() works
unchanged for both legacy and API paths.

Refs [VDY-83](https://linear.app/getsentry/issue/VDY-83/discord-api-driven-integration-setup)

Author: evanpurkhiser

src/sentry/integrations/discord/integration.py

@@ -8,8 +8,10 @@
 from django.http.request import HttpRequest
 from django.http.response import HttpResponseBase
 from django.utils.translation import gettext_lazy as _
+from rest_framework.fields import CharField
 
 from sentry import options
+from sentry.api.serializers.rest_framework.base import CamelSnakeSerializer
 from sentry.constants import ObjectStatus
 from sentry.integrations.base import (
     FeatureDescription,
@@ -32,7 +34,8 @@
 )
 from sentry.notifications.platform.target import IntegrationNotificationTarget
 from sentry.organizations.services.organization.model import RpcOrganization
-from sentry.pipeline.views.base import PipelineView
+from sentry.pipeline.types import PipelineStepResult
+from sentry.pipeline.views.base import ApiPipelineSteps, PipelineView
 from sentry.shared_integrations.exceptions import ApiError, IntegrationError
 from sentry.utils.http import absolute_uri
 
@@ -141,6 +144,64 @@ def uninstall(self) -> None:
             return
 
 
+class DiscordOAuthApiSerializer(CamelSnakeSerializer):
+    code = CharField(required=True)
+    state = CharField(required=True)
+    guild_id = CharField(required=True)
+
+
+class DiscordOAuthApiStep:
+    """API-mode OAuth step for Discord integration setup.
+
+    Discord's OAuth flow is unique: the authorize URL includes bot permissions,
+    and the callback returns a guild_id alongside the authorization code.
+    This step handles both, binding guild_id and code to pipeline state.
+    """
+
+    step_name = "oauth_login"
+
+    def __init__(
+        self,
+        client_id: str,
+        permissions: int,
+        scopes: frozenset[str],
+        redirect_url: str,
+    ) -> None:
+        self.client_id = client_id
+        self.permissions = permissions
+        self.scopes = scopes
+        self.redirect_url = redirect_url
+
+    def get_step_data(self, pipeline: IntegrationPipeline, request: HttpRequest) -> dict[str, str]:
+        params = urlencode(
+            {
+                "client_id": self.client_id,
+                "permissions": self.permissions,
+                "scope": " ".join(self.scopes),
+                "response_type": "code",
+                "state": pipeline.signature,
+                "redirect_uri": self.redirect_url,
+            }
+        )
+        return {"oauthUrl": f"https://discord.com/api/oauth2/authorize?{params}"}
+
+    def get_serializer_cls(self) -> type:
+        return DiscordOAuthApiSerializer
+
+    def handle_post(
+        self,
+        validated_data: dict[str, str],
+        pipeline: IntegrationPipeline,
+        request: HttpRequest,
+    ) -> PipelineStepResult:
+        if validated_data["state"] != pipeline.signature:
+            return PipelineStepResult.error("An error occurred while validating your request.")
+
+        pipeline.bind_state("guild_id", validated_data["guild_id"])
+        pipeline.bind_state("code", validated_data["code"])
+        return PipelineStepResult.advance()
+
+
 class DiscordIntegrationProvider(IntegrationProvider):
     key = IntegrationProviderSlug.DISCORD.value
     name = "Discord"
@@ -176,6 +237,16 @@ def __init__(self) -> None:
     def get_pipeline_views(self) -> Sequence[PipelineView[IntegrationPipeline]]:
         return [DiscordInstallPipeline(self.get_params_for_oauth())]
 
+    def get_pipeline_api_steps(self) -> ApiPipelineSteps[IntegrationPipeline]:
+        return [
+            DiscordOAuthApiStep(
+                client_id=self.application_id,
+                permissions=self.bot_permissions,
+                scopes=self.oauth_scopes,
+                redirect_url=self.setup_url,
+            ),
+        ]
+
     def build_integration(self, state: Mapping[str, Any]) -> IntegrationData:
         guild_id = str(state.get("guild_id"))
 

tests/sentry/integrations/discord/test_integration.py

@@ -1,8 +1,12 @@
+from __future__ import annotations
+
+from typing import Any
 from unittest import mock
 from urllib.parse import parse_qs, urlencode, urlparse
 
 import pytest
 import responses
+from django.urls import reverse
 from responses.matchers import header_matcher, json_params_matcher
 
 from sentry import audit_log, options
@@ -18,6 +22,8 @@
     DiscordIntegrationProvider,
 )
 from sentry.integrations.models.integration import Integration
+from sentry.integrations.models.organization_integration import OrganizationIntegration
+from sentry.integrations.pipeline import IntegrationPipeline
 from sentry.models.auditlogentry import AuditLogEntry
 from sentry.notifications.platform.discord.provider import DiscordRenderable
 from sentry.notifications.platform.target import IntegrationNotificationTarget
@@ -30,7 +36,7 @@
     IntegrationConfigurationError,
     IntegrationError,
 )
-from sentry.testutils.cases import IntegrationTestCase, TestCase
+from sentry.testutils.cases import APITestCase, IntegrationTestCase, TestCase
 from sentry.testutils.silo import control_silo_test
 from sentry.utils import json
 
@@ -552,3 +558,128 @@ def test_send_notification_api_error(self, mock_send: mock.MagicMock) -> None:
             self.installation.send_notification(target=self.target, payload=payload)
 
         assert str(e.value) == error_payload
+
+
+@control_silo_test
+class DiscordApiPipelineTest(APITestCase):
+    endpoint = "sentry-api-0-organization-pipeline"
+    method = "post"
+
+    guild_id = "1234567890"
+    guild_name = "Cool server"
+
+    def setUp(self) -> None:
+        super().setUp()
+        self.login_as(self.user)
+        self.application_id = "application-id"
+        self.public_key = "public-key"
+        self.bot_token = "bot-token"
+        self.client_secret = "client-secret"
+        options.set("discord.application-id", self.application_id)
+        options.set("discord.public-key", self.public_key)
+        options.set("discord.bot-token", self.bot_token)
+        options.set("discord.client-secret", self.client_secret)
+
+    def tearDown(self) -> None:
+        responses.reset()
+        super().tearDown()
+
+    def _get_pipeline_url(self) -> str:
+        return reverse(
+            self.endpoint,
+            args=[self.organization.slug, IntegrationPipeline.pipeline_name],
+        )
+
+    def _initialize_pipeline(self) -> Any:
+        return self.client.post(
+            self._get_pipeline_url(),
+            data={"action": "initialize", "provider": "discord"},
+            format="json",
+        )
+
+    def _advance_step(self, data: dict[str, Any]) -> Any:
+        return self.client.post(self._get_pipeline_url(), data=data, format="json")
+
+    def _get_pipeline_signature(self, resp: Any) -> str:
+        return resp.data["data"]["oauthUrl"].split("state=")[1].split("&")[0]
+
+    @responses.activate
+    def test_initialize_pipeline(self) -> None:
+        resp = self._initialize_pipeline()
+        assert resp.status_code == 200
+        assert resp.data["step"] == "oauth_login"
+        assert resp.data["stepIndex"] == 0
+        assert resp.data["totalSteps"] == 1
+        assert resp.data["provider"] == "discord"
+        oauth_url = resp.data["data"]["oauthUrl"]
+        assert "discord.com/api/oauth2/authorize" in oauth_url
+        assert "permissions=" in oauth_url
+
+        parsed = urlparse(oauth_url)
+        params = parse_qs(parsed.query)
+        assert params["client_id"] == [self.application_id]
+        assert params["permissions"] == [str(DiscordIntegrationProvider.bot_permissions)]
+        requested_scopes = set(params["scope"][0].split(" "))
+        assert requested_scopes == DiscordIntegrationProvider.oauth_scopes
+
+    @responses.activate
+    def test_oauth_step_missing_guild_id(self) -> None:
+        resp = self._initialize_pipeline()
+        pipeline_signature = self._get_pipeline_signature(resp)
+        resp = self._advance_step({"code": "auth-code", "state": pipeline_signature})
+        assert resp.status_code == 400
+
+    @responses.activate
+    @mock.patch("sentry.integrations.discord.client.DiscordClient.set_application_command")
+    def test_full_pipeline_flow(self, mock_set_application_command: mock.MagicMock) -> None:
+        responses.add(
+            responses.GET,
+            url=f"{DiscordClient.base_url}{GUILD_URL.format(guild_id=self.guild_id)}",
+            match=[header_matcher({"Authorization": f"Bot {self.bot_token}"})],
+            json={"id": self.guild_id, "name": self.guild_name},
+        )
+        responses.add(
+            responses.GET,
+            url=f"{DiscordClient.base_url}{APPLICATION_COMMANDS_URL.format(application_id=self.application_id)}",
+            match=[header_matcher({"Authorization": f"Bot {self.bot_token}"})],
+            json=COMMANDS,
+        )
+        responses.add(
+            responses.POST,
+            url=f"{DISCORD_BASE_URL}/oauth2/token",
+            json={"access_token": "access_token"},
+        )
+        responses.add(
+            responses.GET,
+            url=f"{DiscordClient.base_url}/users/@me",
+            json={"id": "user_1234"},
+        )
+        responses.add(
+            responses.GET,
+            url=f"{DiscordClient.base_url}/users/@me/guilds/{self.guild_id}/member",
+            json={},
+        )
+
+        resp = self._initialize_pipeline()
+        assert resp.data["step"] == "oauth_login"
+        pipeline_signature = self._get_pipeline_signature(resp)
+
+        resp = self._advance_step(
+            {
+                "code": "discord-auth-code",
+                "state": pipeline_signature,
+                "guildId": self.guild_id,
+            }
+        )
+        assert resp.status_code == 200
+        assert resp.data["status"] == "complete"
+        assert "data" in resp.data
+
+        integration = Integration.objects.get(provider="discord")
+        assert integration.external_id == self.guild_id
+        assert integration.name == self.guild_name
+
+        assert OrganizationIntegration.objects.filter(
+            organization_id=self.organization.id,
+            integration=integration,
+        ).exists()