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Google HTTP クライアント ライブラリ v1.14.1 を使用して、Box API でこの特定のメソッドhttp://developers.box.com/docs/#files-upload-a-fileを呼び出そうとしています。現在、これを行う方法はありません。

http://hc.apache.org/httpclient-3.x/methods/multipartpost.htmlを使用していた場合、StringPart の 2 つのアイテムと FilePart の 1 つのアイテムを追加します。

Google HTTP クライアント ライブラリでは、上記で参照されている StringPart のように、純粋な名前と値のペアを処理できないと思われる MultipartContent および Part クラスのみが表示されます。

以下は、Apache HTTP クライアントの例からの抜粋です。

HttpPost httppost = new HttpPost("http://localhost:8080" +
                "/servlets-examples/servlet/RequestInfoExample");

FileBody bin = new FileBody(new File(args[0]));
StringBody comment = new StringBody("A binary file of some kind");

MultipartEntity reqEntity = new MultipartEntity();
reqEntity.addPart("bin", bin);
reqEntity.addPart("comment", comment);

httppost.setEntity(reqEntity);

同様のことを達成したいのですが、Google HTTP クライアントを使用しています。どんな提案でも大歓迎です!

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2 に答える 2

6

調査の結果、Box API には Content-Type: multipart/form-data が必要であることがわかり、リクエストを適切に作成しました。私が使用していた Google HTTP Client のバージョンでは不可能だったので、自分で MultipartFormDataContent クラスを実装したところ、ライブラリに完全に適合しました。これがクラスの完全なリストです。ライブラリに含まれる可能性があります。

/*
 * Copyright (c) 2013 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */
/**
 * This is a modification of com.google.api.client.http.MultipartContent from
 * Google HTTP Client library to support multipart/form-data requests.
 *
 * The original author is Yaniv Inbar.
 */
public class MultipartFormDataContent extends AbstractHttpContent {
    private static final String NEWLINE = "\r\n";
    private static final String TWO_DASHES = "--";
    private ArrayList<Part> parts = new ArrayList<Part>();

    public MultipartFormDataContent() {
        super(new HttpMediaType("multipart/form-data").setParameter("boundary", "__END_OF_PART__"));
    }

    @Override
    public void writeTo(OutputStream out) throws IOException {
        Writer writer = new OutputStreamWriter(out, getCharset());
        String boundary = getBoundary();
        for (Part part : parts) {
            HttpHeaders headers = new HttpHeaders().setAcceptEncoding(null);
            if (part.headers != null) {
                headers.fromHttpHeaders(part.headers);
            }
            headers.setContentEncoding(null)
                   .setUserAgent(null)
                   .setContentType(null)
                   .setContentLength(null);
            // analyze the content
            HttpContent content = part.content;
            StreamingContent streamingContent = null;
            String contentDisposition = String.format("form-data; name=\"%s\"", part.name);
            if (part.filename != null) {
                headers.setContentType(content.getType());
                contentDisposition += String.format("; filename=\"%s\"", part.filename);
            }
            headers.set("Content-Disposition", contentDisposition);
            HttpEncoding encoding = part.encoding;
            if (encoding == null) {
                streamingContent = content;
            } else {
                headers.setContentEncoding(encoding.getName());
                streamingContent = new HttpEncodingStreamingContent(content, encoding);
            }
            // write separator
            writer.write(TWO_DASHES);
            writer.write(boundary);
            writer.write(NEWLINE);
            // write headers
            HttpHeaders.serializeHeadersForMultipartRequests(headers, null, null, writer);
            // write content
            if (streamingContent != null) {
                writer.write(NEWLINE);
                writer.flush();
                streamingContent.writeTo(out);
                writer.write(NEWLINE);
            }
        }
        // write end separator
        writer.write(TWO_DASHES);
        writer.write(boundary);
        writer.write(TWO_DASHES);
        writer.write(NEWLINE);
        writer.flush();
    }

    @Override
    public boolean retrySupported() {
        for (Part part : parts) {
            if (!part.content.retrySupported()) {
                return false;
            }
        }
        return true;
    }

    @Override
    public MultipartFormDataContent setMediaType(HttpMediaType mediaType) {
        super.setMediaType(mediaType);
        return this;
    }

    /**
     * Adds an HTTP multipart part.
     *
     * <p>
     * Overriding is only supported for the purpose of calling the super
     * implementation and changing the return type, but nothing else.
     * </p>
     */
    public MultipartFormDataContent addPart(Part part) {
        parts.add(Preconditions.checkNotNull(part));
        return this;
    }

    /**
     * Sets the boundary string to use.
     *
     * <p>
     * Defaults to {@code "END_OF_PART"}.
     * </p>
     *
     * <p>
     * Overriding is only supported for the purpose of calling the super
     * implementation and changing the return type, but nothing else.
     * </p>
     */
    public MultipartFormDataContent setBoundary(String boundary) {
        getMediaType().setParameter("boundary", Preconditions.checkNotNull(boundary));
        return this;
    }

    /**
     * Single part of a multi-part request.
     *
     * <p>
     * Implementation is not thread-safe.
     * </p>
     */
    public static final class Part {
        private String name;
        private String filename;
        private HttpContent content;
        private HttpHeaders headers;
        private HttpEncoding encoding;

        public Part setContent(HttpContent content) {
            this.content = content;
            return this;
        }

        public Part setHeaders(HttpHeaders headers) {
            this.headers = headers;
            return this;
        }

        public Part setEncoding(HttpEncoding encoding) {
            this.encoding = encoding;
            return this;
        }

        public Part setName(String name) {
            this.name = name;
            return this;
        }

        public Part setFilename(String filename) {
            this.filename = filename;
            return this;
        }
    }
}
于 2013-04-14T14:54:23.130 に答える