feat: multipart, etc.. (denoland/deno_std#180)

Original: https://github.com/denoland/deno_std/commit/fda9c98d055091fa886fa444ebd1adcd2ecd21bc

1 files changed, 492 insertions, 0 deletions

diff --git a/multipart/multipart.ts b/multipart/multipart.ts
new file mode 100644
index 000000000..f0caa2160
--- /dev/null
+++ b/multipart/multipart.ts
@@ -0,0 +1,492 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+import { Buffer, Closer, copy, Reader, ReadResult, remove, Writer } from "deno";
+
+import { FormFile } from "./formfile.ts";
+import {
+  bytesFindIndex,
+  bytesFindLastIndex,
+  bytesHasPrefix,
+  bytesEqual
+} from "../bytes/bytes.ts";
+import { copyN } from "../io/ioutil.ts";
+import { MultiReader } from "../io/readers.ts";
+import { tempFile } from "../io/util.ts";
+import { BufReader, BufState, BufWriter } from "../io/bufio.ts";
+import { TextProtoReader } from "../textproto/mod.ts";
+import { encoder } from "../strings/strings.ts";
+import * as path from "../fs/path.ts";
+
+function randomBoundary() {
+  let boundary = "--------------------------";
+  for (let i = 0; i < 24; i++) {
+    boundary += Math.floor(Math.random() * 10).toString(16);
+  }
+  return boundary;
+}
+
+/** Reader for parsing multipart/form-data */
+export class MultipartReader {
+  readonly newLine = encoder.encode("\r\n");
+  readonly newLineDashBoundary = encoder.encode(`\r\n--${this.boundary}`);
+  readonly dashBoundaryDash = encoder.encode(`--${this.boundary}--`);
+  readonly dashBoundary = encoder.encode(`--${this.boundary}`);
+  readonly bufReader: BufReader;
+
+  constructor(private reader: Reader, private boundary: string) {
+    this.bufReader = new BufReader(reader);
+  }
+
+  /** Read all form data from stream.
+   * If total size of stored data in memory exceed maxMemory,
+   * overflowed file data will be written to temporal files.
+   * String field values are never written to files */
+  async readForm(
+    maxMemory: number
+  ): Promise<{ [key: string]: string | FormFile }> {
+    const result = Object.create(null);
+    let maxValueBytes = maxMemory + (10 << 20);
+    const buf = new Buffer(new Uint8Array(maxValueBytes));
+    for (;;) {
+      const p = await this.nextPart();
+      if (!p) {
+        break;
+      }
+      if (p.formName === "") {
+        continue;
+      }
+      buf.reset();
+      if (!p.fileName) {
+        // value
+        const n = await copyN(buf, p, maxValueBytes);
+        maxValueBytes -= n;
+        if (maxValueBytes < 0) {
+          throw new RangeError("message too large");
+        }
+        const value = buf.toString();
+        result[p.formName] = value;
+        continue;
+      }
+      // file
+      let formFile: FormFile;
+      const n = await copy(buf, p);
+      if (n > maxMemory) {
+        // too big, write to disk and flush buffer
+        const ext = path.extname(p.fileName);
+        const { file, filepath } = await tempFile(".", {
+          prefix: "multipart-",
+          postfix: ext
+        });
+        try {
+          const size = await copyN(
+            file,
+            new MultiReader(buf, p),
+            maxValueBytes
+          );
+          file.close();
+          formFile = {
+            filename: p.fileName,
+            type: p.headers.get("content-type"),
+            tempfile: filepath,
+            size
+          };
+        } catch (e) {
+          await remove(filepath);
+        }
+      } else {
+        formFile = {
+          filename: p.fileName,
+          type: p.headers.get("content-type"),
+          content: buf.bytes(),
+          size: buf.bytes().byteLength
+        };
+        maxMemory -= n;
+        maxValueBytes -= n;
+      }
+      result[p.formName] = formFile;
+    }
+    return result;
+  }
+
+  private currentPart: PartReader;
+  private partsRead: number;
+
+  private async nextPart(): Promise<PartReader> {
+    if (this.currentPart) {
+      this.currentPart.close();
+    }
+    if (bytesEqual(this.dashBoundary, encoder.encode("--"))) {
+      throw new Error("boundary is empty");
+    }
+    let expectNewPart = false;
+    for (;;) {
+      const [line, state] = await this.bufReader.readSlice("\n".charCodeAt(0));
+      if (state === "EOF" && this.isFinalBoundary(line)) {
+        break;
+      }
+      if (state) {
+        throw new Error("aa" + state.toString());
+      }
+      if (this.isBoundaryDelimiterLine(line)) {
+        this.partsRead++;
+        const r = new TextProtoReader(this.bufReader);
+        const [headers, state] = await r.readMIMEHeader();
+        if (state) {
+          throw state;
+        }
+        const np = new PartReader(this, headers);
+        this.currentPart = np;
+        return np;
+      }
+      if (this.isFinalBoundary(line)) {
+        break;
+      }
+      if (expectNewPart) {
+        throw new Error(`expecting a new Part; got line ${line}`);
+      }
+      if (this.partsRead === 0) {
+        continue;
+      }
+      if (bytesEqual(line, this.newLine)) {
+        expectNewPart = true;
+        continue;
+      }
+      throw new Error(`unexpected line in next(): ${line}`);
+    }
+  }
+
+  private isFinalBoundary(line: Uint8Array) {
+    if (!bytesHasPrefix(line, this.dashBoundaryDash)) {
+      return false;
+    }
+    let rest = line.slice(this.dashBoundaryDash.length, line.length);
+    return rest.length === 0 || bytesEqual(skipLWSPChar(rest), this.newLine);
+  }
+
+  private isBoundaryDelimiterLine(line: Uint8Array) {
+    if (!bytesHasPrefix(line, this.dashBoundary)) {
+      return false;
+    }
+    const rest = line.slice(this.dashBoundary.length);
+    return bytesEqual(skipLWSPChar(rest), this.newLine);
+  }
+}
+
+function skipLWSPChar(u: Uint8Array): Uint8Array {
+  const ret = new Uint8Array(u.length);
+  const sp = " ".charCodeAt(0);
+  const ht = "\t".charCodeAt(0);
+  let j = 0;
+  for (let i = 0; i < u.length; i++) {
+    if (u[i] === sp || u[i] === ht) continue;
+    ret[j++] = u[i];
+  }
+  return ret.slice(0, j);
+}
+
+let i = 0;
+
+class PartReader implements Reader, Closer {
+  n: number = 0;
+  total: number = 0;
+  bufState: BufState = null;
+  index = i++;
+
+  constructor(private mr: MultipartReader, public readonly headers: Headers) {}
+
+  async read(p: Uint8Array): Promise<ReadResult> {
+    const br = this.mr.bufReader;
+    const returnResult = (nread: number, bufState: BufState): ReadResult => {
+      if (bufState && bufState !== "EOF") {
+        throw bufState;
+      }
+      return { nread, eof: bufState === "EOF" };
+    };
+    if (this.n === 0 && !this.bufState) {
+      const [peek] = await br.peek(br.buffered());
+      const [n, state] = scanUntilBoundary(
+        peek,
+        this.mr.dashBoundary,
+        this.mr.newLineDashBoundary,
+        this.total,
+        this.bufState
+      );
+      this.n = n;
+      this.bufState = state;
+      if (this.n === 0 && !this.bufState) {
+        const [_, state] = await br.peek(peek.length + 1);
+        this.bufState = state;
+        if (this.bufState === "EOF") {
+          this.bufState = new RangeError("unexpected eof");
+        }
+      }
+    }
+    if (this.n === 0) {
+      return returnResult(0, this.bufState);
+    }
+
+    let n = 0;
+    if (p.byteLength > this.n) {
+      n = this.n;
+    }
+    const buf = p.slice(0, n);
+    const [nread] = await this.mr.bufReader.readFull(buf);
+    p.set(buf);
+    this.total += nread;
+    this.n -= nread;
+    if (this.n === 0) {
+      return returnResult(n, this.bufState);
+    }
+    return returnResult(n, null);
+  }
+
+  close(): void {}
+
+  private contentDisposition: string;
+  private contentDispositionParams: { [key: string]: string };
+
+  private getContentDispositionParams() {
+    if (this.contentDispositionParams) return this.contentDispositionParams;
+    const cd = this.headers.get("content-disposition");
+    const params = {};
+    const comps = cd.split(";");
+    this.contentDisposition = comps[0];
+    comps
+      .slice(1)
+      .map(v => v.trim())
+      .map(kv => {
+        const [k, v] = kv.split("=");
+        if (v) {
+          const s = v.charAt(0);
+          const e = v.charAt(v.length - 1);
+          if ((s === e && s === '"') || s === "'") {
+            params[k] = v.substr(1, v.length - 2);
+          } else {
+            params[k] = v;
+          }
+        }
+      });
+    return (this.contentDispositionParams = params);
+  }
+
+  get fileName(): string {
+    return this.getContentDispositionParams()["filename"];
+  }
+
+  get formName(): string {
+    const p = this.getContentDispositionParams();
+    if (this.contentDisposition === "form-data") {
+      return p["name"];
+    }
+    return "";
+  }
+}
+
+export function scanUntilBoundary(
+  buf: Uint8Array,
+  dashBoundary: Uint8Array,
+  newLineDashBoundary: Uint8Array,
+  total: number,
+  state: BufState
+): [number, BufState] {
+  if (total === 0) {
+    if (bytesHasPrefix(buf, dashBoundary)) {
+      switch (matchAfterPrefix(buf, dashBoundary, state)) {
+        case -1:
+          return [dashBoundary.length, null];
+        case 0:
+          return [0, null];
+        case 1:
+          return [0, "EOF"];
+      }
+      if (bytesHasPrefix(dashBoundary, buf)) {
+        return [0, state];
+      }
+    }
+  }
+  const i = bytesFindIndex(buf, newLineDashBoundary);
+  if (i >= 0) {
+    switch (matchAfterPrefix(buf.slice(i), newLineDashBoundary, state)) {
+      case -1:
+        return [i + newLineDashBoundary.length, null];
+      case 0:
+        return [i, null];
+      case 1:
+        return [i, "EOF"];
+    }
+  }
+  if (bytesHasPrefix(newLineDashBoundary, buf)) {
+    return [0, state];
+  }
+  const j = bytesFindLastIndex(buf, newLineDashBoundary.slice(0, 1));
+  if (j >= 0 && bytesHasPrefix(newLineDashBoundary, buf.slice(j))) {
+    return [j, null];
+  }
+  return [buf.length, state];
+}
+
+export function matchAfterPrefix(
+  a: Uint8Array,
+  prefix: Uint8Array,
+  bufState: BufState
+): number {
+  if (a.length === prefix.length) {
+    if (bufState) {
+      return 1;
+    }
+    return 0;
+  }
+  const c = a[prefix.length];
+  if (
+    c === " ".charCodeAt(0) ||
+    c === "\t".charCodeAt(0) ||
+    c === "\r".charCodeAt(0) ||
+    c === "\n".charCodeAt(0) ||
+    c === "-".charCodeAt(0)
+  ) {
+    return 1;
+  }
+  return -1;
+}
+
+class PartWriter implements Writer {
+  closed = false;
+  private readonly partHeader: string;
+  private headersWritten: boolean = false;
+
+  constructor(
+    private writer: Writer,
+    readonly boundary: string,
+    public headers: Headers,
+    isFirstBoundary: boolean
+  ) {
+    let buf = "";
+    if (isFirstBoundary) {
+      buf += `--${boundary}\r\n`;
+    } else {
+      buf += `\r\n--${boundary}\r\n`;
+    }
+    for (const [key, value] of headers.entries()) {
+      buf += `${key}: ${value}\r\n`;
+    }
+    buf += `\r\n`;
+    this.partHeader = buf;
+  }
+
+  close(): void {
+    this.closed = true;
+  }
+
+  async write(p: Uint8Array): Promise<number> {
+    if (this.closed) {
+      throw new Error("part is closed");
+    }
+    if (!this.headersWritten) {
+      await this.writer.write(encoder.encode(this.partHeader));
+      this.headersWritten = true;
+    }
+    return this.writer.write(p);
+  }
+}
+
+function checkBoundary(b: string) {
+  if (b.length < 1 || b.length > 70) {
+    throw new Error("invalid boundary length: " + b.length);
+  }
+  const end = b.length - 1;
+  for (let i = 0; i < end; i++) {
+    const c = b.charAt(i);
+    if (!c.match(/[a-zA-Z0-9'()+_,\-./:=?]/) || (c === " " && i !== end)) {
+      throw new Error("invalid boundary character: " + c);
+    }
+  }
+  return b;
+}
+
+/** Writer for creating multipart/form-data */
+export class MultipartWriter {
+  private readonly _boundary: string;
+
+  get boundary() {
+    return this._boundary;
+  }
+
+  private lastPart: PartWriter;
+  private bufWriter: BufWriter;
+  private isClosed: boolean = false;
+
+  constructor(private readonly writer: Writer, boundary?: string) {
+    if (boundary !== void 0) {
+      this._boundary = checkBoundary(boundary);
+    } else {
+      this._boundary = randomBoundary();
+    }
+    this.bufWriter = new BufWriter(writer);
+  }
+
+  formDataContentType(): string {
+    return `multipart/form-data; boundary=${this.boundary}`;
+  }
+
+  private createPart(headers: Headers): Writer {
+    if (this.isClosed) {
+      throw new Error("multipart: writer is closed");
+    }
+    if (this.lastPart) {
+      this.lastPart.close();
+    }
+    const part = new PartWriter(
+      this.writer,
+      this.boundary,
+      headers,
+      !this.lastPart
+    );
+    this.lastPart = part;
+    return part;
+  }
+
+  createFormFile(field: string, filename: string): Writer {
+    const h = new Headers();
+    h.set(
+      "Content-Disposition",
+      `form-data; name="${field}"; filename="${filename}"`
+    );
+    h.set("Content-Type", "application/octet-stream");
+    return this.createPart(h);
+  }
+
+  createFormField(field: string): Writer {
+    const h = new Headers();
+    h.set("Content-Disposition", `form-data; name="${field}"`);
+    h.set("Content-Type", "application/octet-stream");
+    return this.createPart(h);
+  }
+
+  async writeField(field: string, value: string) {
+    const f = await this.createFormField(field);
+    await f.write(encoder.encode(value));
+  }
+
+  async writeFile(field: string, filename: string, file: Reader) {
+    const f = await this.createFormFile(field, filename);
+    await copy(f, file);
+  }
+
+  private flush(): Promise<BufState> {
+    return this.bufWriter.flush();
+  }
+
+  /** Close writer. No additional data can be writen to stream */
+  async close() {
+    if (this.isClosed) {
+      throw new Error("multipart: writer is closed");
+    }
+    if (this.lastPart) {
+      this.lastPart.close();
+      this.lastPart = void 0;
+    }
+    await this.writer.write(encoder.encode(`\r\n--${this.boundary}--\r\n`));
+    await this.flush();
+    this.isClosed = true;
+  }
+}