diff options
Diffstat (limited to 'deno/mail-relay/mail.ts')
| -rw-r--r-- | deno/mail-relay/mail.ts | 330 |
1 files changed, 0 insertions, 330 deletions
diff --git a/deno/mail-relay/mail.ts b/deno/mail-relay/mail.ts deleted file mode 100644 index d6dfe65..0000000 --- a/deno/mail-relay/mail.ts +++ /dev/null @@ -1,330 +0,0 @@ -import { encodeBase64 } from "@std/encoding/base64"; -import { parse } from "@std/csv/parse"; -import emailAddresses from "email-addresses"; - -class MailSimpleParseError extends Error {} - -class MailSimpleParsedHeaders { - constructor(public fields: [key: string, value: string][]) {} - - getFirst(fieldKey: string): string | undefined { - for (const [key, value] of this.fields) { - if (key.toLowerCase() === fieldKey.toLowerCase()) return value; - } - return undefined; - } - - messageId(): string | undefined { - const messageIdField = this.getFirst("message-id"); - if (messageIdField == null) return undefined; - - const match = messageIdField.match(/\<(.*?)\>/); - if (match != null) { - return match[1]; - } else { - console.warn("Invalid message-id header of mail: " + messageIdField); - return undefined; - } - } - - date(invalidToUndefined: boolean = true): Date | undefined { - const dateField = this.getFirst("date"); - if (dateField == null) return undefined; - - const date = new Date(dateField); - if (invalidToUndefined && isNaN(date.getTime())) { - console.warn(`Invalid date string (${dateField}) found in header.`); - return undefined; - } - return date; - } - - recipients(options?: { domain?: string; headers?: string[] }): Set<string> { - const domain = options?.domain; - const headers = options?.headers ?? ["to", "cc", "bcc", "x-original-to"]; - const recipients = new Set<string>(); - for (const [key, value] of this.fields) { - if (headers.includes(key.toLowerCase())) { - emailAddresses - .parseAddressList(value) - ?.flatMap((a) => (a.type === "mailbox" ? a : a.addresses)) - ?.forEach(({ address }) => { - if (domain == null || address.endsWith(domain)) { - recipients.add(address); - } - }); - } - } - return recipients; - } -} - -class MailSimpleParsedSections { - header: string; - body: string; - eol: string; - sep: string; - - constructor(raw: string) { - const twoEolMatch = raw.match(/(\r?\n)(\r?\n)/); - if (twoEolMatch == null) { - throw new MailSimpleParseError( - "No header/body section separator (2 successive EOLs) found.", - ); - } - - const [eol, sep] = [twoEolMatch[1], twoEolMatch[2]]; - - if (eol !== sep) { - console.warn("Different EOLs (\\r\\n, \\n) found."); - } - - this.header = raw.slice(0, twoEolMatch.index!); - this.body = raw.slice(twoEolMatch.index! + eol.length + sep.length); - this.eol = eol; - this.sep = sep; - } - - headers(): MailSimpleParsedHeaders { - const headers = [] as [key: string, value: string][]; - - let field: string | null = null; - let lineNumber = 1; - - const handleField = () => { - if (field == null) return; - const sepPos = field.indexOf(":"); - if (sepPos === -1) { - throw new MailSimpleParseError(`No ':' in the header line: ${field}`); - } - headers.push([field.slice(0, sepPos).trim(), field.slice(sepPos + 1)]); - field = null; - }; - - for (const line of this.header.trimEnd().split(/\r?\n|\r/)) { - if (line.match(/^\s/)) { - if (field == null) { - throw new MailSimpleParseError("Header section starts with a space."); - } - field += line; - } else { - handleField(); - field = line; - } - lineNumber += 1; - } - - handleField(); - - return new MailSimpleParsedHeaders(headers); - } -} - -export class Mail { - constructor(public raw: string) {} - - toUtf8Bytes(): Uint8Array { - const utf8Encoder = new TextEncoder(); - return utf8Encoder.encode(this.raw); - } - - toBase64(): string { - return encodeBase64(this.raw); - } - - startSimpleParse() { - return { sections: () => new MailSimpleParsedSections(this.raw) }; - } - - simpleFindAllAddresses(): string[] { - const re = /,?\<?([a-z0-9_'+\-\.]+\@[a-z0-9_'+\-\.]+)\>?,?/gi; - return [...this.raw.matchAll(re)].map((m) => m[1]); - } -} - -export type MailDeliverResultKind = "done" | "fail"; - -export interface MailDeliverRecipientResult { - kind: MailDeliverResultKind; - message: string; - cause?: unknown; -} - -export class MailDeliverResult { - message: string = ""; - recipients: Map<string, MailDeliverRecipientResult> = new Map(); - - constructor(public mail: Mail) {} - - hasError(): boolean { - return ( - this.recipients.size === 0 || - this.recipients.values().some((r) => r.kind !== "done") - ); - } - - [Symbol.for("Deno.customInspect")]() { - return [ - `message: ${this.message}`, - ...this.recipients - .entries() - .map( - ([recipient, result]) => - `${recipient} [${result.kind}]: ${result.message}`, - ), - ].join("\n"); - } -} - -export class MailDeliverContext { - readonly recipients: Set<string> = new Set(); - readonly result; - - constructor(public mail: Mail) { - this.result = new MailDeliverResult(this.mail); - } -} - -export interface MailDeliverHook { - callback(context: MailDeliverContext): Promise<void>; -} - -export abstract class MailDeliverer { - abstract readonly name: string; - preHooks: MailDeliverHook[] = []; - postHooks: MailDeliverHook[] = []; - - protected abstract doDeliver( - mail: Mail, - context: MailDeliverContext, - ): Promise<void>; - - async deliverRaw(rawMail: string) { - return await this.deliver({ mail: new Mail(rawMail) }); - } - - async deliver(options: { - mail: Mail; - recipients?: string[]; - }): Promise<MailDeliverResult> { - console.info(`Begin to deliver mail via ${this.name}...`); - - const context = new MailDeliverContext(options.mail); - options.recipients?.forEach((r) => context.recipients.add(r)); - - for (const hook of this.preHooks) { - await hook.callback(context); - } - - await this.doDeliver(context.mail, context); - - for (const hook of this.postHooks) { - await hook.callback(context); - } - - console.info("Deliver result:"); - console.info(context.result); - - if (context.result.hasError()) { - throw new Error("Mail failed to deliver."); - } - - return context.result; - } -} - -export abstract class SyncMailDeliverer extends MailDeliverer { - #last: Promise<void> = Promise.resolve(); - - override async deliver(options: { - mail: Mail; - recipients?: string[]; - }): Promise<MailDeliverResult> { - console.info( - "The mail deliverer is sync. Wait for last delivering done...", - ); - await this.#last; - const result = super.deliver(options); - this.#last = result.then( - () => {}, - () => {}, - ); - return result; - } -} - -export class RecipientFromHeadersHook implements MailDeliverHook { - constructor(public mailDomain: string) {} - - callback(context: MailDeliverContext) { - if (context.recipients.size !== 0) { - console.warn( - "Recipients are already filled. Won't set them with ones in headers.", - ); - } else { - context.mail - .startSimpleParse() - .sections() - .headers() - .recipients({ - domain: this.mailDomain, - }) - .forEach((r) => context.recipients.add(r)); - - console.info( - "Recipients found from mail headers: " + - [...context.recipients].join(", "), - ); - } - return Promise.resolve(); - } -} - -export class FallbackRecipientHook implements MailDeliverHook { - constructor(public fallback: Set<string> = new Set()) {} - - callback(context: MailDeliverContext) { - if (context.recipients.size === 0) { - console.info( - "No recipients, fill with fallback: " + [...this.fallback].join(", "), - ); - this.fallback.forEach((a) => context.recipients.add(a)); - } - return Promise.resolve(); - } -} - -export class AliasRecipientMailHook implements MailDeliverHook { - #aliasFile; - - constructor(aliasFile: string) { - this.#aliasFile = aliasFile; - } - - async #parseAliasFile(): Promise<Map<string, string>> { - const result = new Map(); - if ((await Deno.stat(this.#aliasFile)).isFile) { - console.info(`Found recipients alias file: ${this.#aliasFile}.`); - const text = await Deno.readTextFile(this.#aliasFile); - const csv = parse(text); - for (const [real, ...aliases] of csv) { - aliases.forEach((a) => result.set(a, real)); - } - } - return result; - } - - async callback(context: MailDeliverContext) { - const aliases = await this.#parseAliasFile(); - for (const recipient of [...context.recipients]) { - const realRecipients = aliases.get(recipient); - if (realRecipients != null) { - console.info( - `Recipient alias resolved: ${recipient} => ${realRecipients}.`, - ); - context.recipients.delete(recipient); - context.recipients.add(realRecipients); - } - } - } -} |
