1
import {
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  BranchName,
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  CommitSha,
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  type WebhookProvider as WebhookProviderValue,
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  type BranchName as BranchNameValue,
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  type CommitSha as CommitShaValue,
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} from "@/contracts";
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import { type WebhookTriggerPayload } from "@/worker/contracts";
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import { normalizeRepositoryUrl } from "@/worker/validation";
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import { HttpError } from "@/worker/http";
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export type ParsedJsonObject = Record<string, unknown>;
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const textDecoder = new TextDecoder();
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export const parseJsonObject = (body: Uint8Array): ParsedJsonObject => {
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  try {
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    const parsed = JSON.parse(textDecoder.decode(body)) as unknown;
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    if (!parsed || typeof parsed !== "object" || Array.isArray(parsed)) {
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      throw new Error("not an object");
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    }
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    return parsed as ParsedJsonObject;
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  } catch (error) {
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    throw new HttpError(400, "invalid_json", "Webhook body must be valid JSON.", error);
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  }
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};
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export const requireRecord = (value: unknown, fieldName: string): ParsedJsonObject => {
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  if (!value || typeof value !== "object" || Array.isArray(value)) {
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    throw new HttpError(400, "invalid_request", `Webhook payload field ${fieldName} is invalid.`);
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  }
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  return value as ParsedJsonObject;
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};
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export const requireString = (value: unknown, fieldName: string): string => {
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  if (typeof value !== "string" || value.length === 0) {
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    throw new HttpError(400, "invalid_request", `Webhook payload field ${fieldName} is invalid.`);
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  }
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  return value;
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};
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export const decodeCommitSha = (value: unknown, fieldName: string): CommitShaValue | null => {
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  if (value === null || value === undefined) {
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    return null;
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  }
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50
  if (typeof value !== "string" || value.length === 0) {
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    throw new HttpError(400, "invalid_request", `Webhook payload field ${fieldName} is invalid.`);
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  }
53
 
54
  if (/^0+$/u.test(value)) {
55
    return null;
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  }
57
 
58
  try {
59
    return CommitSha.assertDecode(value);
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  } catch {
61
    throw new HttpError(400, "invalid_request", `Webhook payload field ${fieldName} is invalid.`);
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  }
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};
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export const decodeBranchFromRef = (ref: string | null): BranchNameValue | null => {
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  if (ref === null) {
67
    return null;
68
  }
69
 
70
  if (!ref.startsWith("refs/heads/")) {
71
    return null;
72
  }
73
 
74
  const branch = ref.slice("refs/heads/".length);
75
  try {
76
    return BranchName.assertDecode(branch);
77
  } catch {
78
    throw new HttpError(400, "invalid_request", "Webhook branch ref is invalid.");
79
  }
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};
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const normalizePushStylePayload = (input: {
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  provider: Extract<WebhookProviderValue, "github" | "gitea">;
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  payload: ParsedJsonObject;
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  eventName: string;
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  resolveRepositoryUrl: (repository: ParsedJsonObject) => string;
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}): WebhookTriggerPayload => {
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  const repository = requireRecord(input.payload.repository, "repository");
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  const isPush = input.eventName === "push";
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  const isPing = input.eventName === "ping";
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  const ref = input.payload.ref === undefined ? null : requireString(input.payload.ref, "ref");
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  return {
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    provider: input.provider,
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    deliveryId: "",
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    eventKind: isPing ? "ping" : isPush ? "push" : "other",
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    eventName: input.eventName,
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    repoUrl: input.resolveRepositoryUrl(repository),
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    ref,
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    branch: decodeBranchFromRef(ref),
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    commitSha: isPush ? decodeCommitSha(input.payload.after, "after") : null,
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    beforeSha: isPush ? decodeCommitSha(input.payload.before, "before") : null,
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  };
104
};
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const normalizeGitHubPayload = (payload: ParsedJsonObject, eventName: string): WebhookTriggerPayload =>
107
  normalizePushStylePayload({
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    provider: "github",
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    payload,
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    eventName,
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    resolveRepositoryUrl: (repository) => {
112
      const fullName = requireString(repository.full_name, "repository.full_name");
113
      return normalizeRepositoryUrl(`https://github.com/${fullName}`);
114
    },
115
  });
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const normalizeGitLabPayload = (payload: ParsedJsonObject, eventName: string): WebhookTriggerPayload => {
118
  const project = requireRecord(payload.project, "project");
119
  const repository = payload.repository === undefined ? null : requireRecord(payload.repository, "repository");
120
  const repoUrlValue =
121
    project.git_http_url ?? project.http_url ?? (repository === null ? undefined : repository.git_http_url);
122
  const repoUrl = normalizeRepositoryUrl(requireString(repoUrlValue, "project.git_http_url"));
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  const ref = payload.ref === undefined ? null : requireString(payload.ref, "ref");
124
  const objectKind = payload.object_kind === undefined ? null : requireString(payload.object_kind, "object_kind");
125
  const payloadEventName = payload.event_name === undefined ? null : requireString(payload.event_name, "event_name");
126
  // GitLab system hooks and test-system-hook payloads are not push or ping
127
  // events in v1, so they stay in the generic non-push bucket.
128
  const isPush = eventName === "Push Hook" && objectKind === "push" && payloadEventName === "push";
129
  const commitSha = isPush ? decodeCommitSha(payload.checkout_sha ?? payload.after, "checkout_sha") : null;
130
 
131
  return {
132
    provider: "gitlab",
133
    deliveryId: "",
134
    eventKind: isPush ? "push" : "other",
135
    eventName,
136
    repoUrl,
137
    ref,
138
    branch: decodeBranchFromRef(ref),
139
    commitSha,
140
    beforeSha: isPush ? decodeCommitSha(payload.before, "before") : null,
141
  };
142
};
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144
const normalizeGiteaPayload = (payload: ParsedJsonObject, eventName: string): WebhookTriggerPayload =>
145
  normalizePushStylePayload({
146
    provider: "gitea",
147
    payload,
148
    eventName,
149
    resolveRepositoryUrl: (repository) =>
150
      normalizeRepositoryUrl(requireString(repository.clone_url, "repository.clone_url")),
151
  });
152
 
153
export const webhookPayloadNormalizers = {
154
  github: normalizeGitHubPayload,
155
  gitlab: normalizeGitLabPayload,
156
  gitea: normalizeGiteaPayload,
157
} as const satisfies Record<
158
  WebhookProviderValue,
159
  (payload: ParsedJsonObject, eventName: string) => WebhookTriggerPayload
160
>;