com.arrow.acs.ApiRequestSigner.java Source code

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Here is the source code for com.arrow.acs.ApiRequestSigner.java

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/*******************************************************************************
 * Copyright (c) 2017 Arrow Electronics, Inc.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Apache License 2.0
 * which accompanies this distribution, and is available at
 * http://apache.org/licenses/LICENSE-2.0
 *
 * Contributors:
 *     Arrow Electronics, Inc.
 *******************************************************************************/
package com.arrow.acs;

import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import org.apache.commons.codec.digest.DigestUtils;
import org.apache.commons.codec.digest.HmacUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.Validate;

public class ApiRequestSigner extends Loggable {
    private String secretKey;
    private String method;
    private String uri;
    private String apiKey;
    private String timestamp;
    private String payload;
    private List<String> parameters;

    private ApiRequestSigner(String secretKey) {
        this.parameters = new ArrayList<>();
        this.secretKey = secretKey;
        this.payload = "";
    }

    public static ApiRequestSigner create(String secretKey) {
        Validate.notEmpty(secretKey, "secretKey is empty");
        return new ApiRequestSigner(secretKey);
    }

    public ApiRequestSigner payload(String payload) {
        Validate.notNull(payload, "payload is null");
        this.payload = payload;
        return this;
    }

    public ApiRequestSigner method(String method) {
        Validate.notEmpty(method, "method is empty");
        this.method = method.toUpperCase();
        return this;
    }

    public ApiRequestSigner canonicalUri(String uri) {
        Validate.notEmpty(uri, "uri is empty");
        this.uri = uri;
        return this;
    }

    public ApiRequestSigner parameter(String name, String value) {
        Validate.notEmpty(name, "name is empty");
        try {
            parameters.add(
                    String.format("%s=%s", URLEncoder.encode(name.toLowerCase(), StandardCharsets.UTF_8.toString()),
                            StringUtils.trimToEmpty(value)));
        } catch (Exception e) {
            throw new AcsSystemException("system error", e);
        }
        return this;
    }

    public ApiRequestSigner apiKey(String apiKey) {
        Validate.notEmpty(apiKey, "apiKey is empty");
        this.apiKey = apiKey;
        return this;
    }

    public ApiRequestSigner timestamp(String timestamp) {
        Validate.notEmpty(timestamp, "timestamp is empty");
        this.timestamp = timestamp;
        return this;
    }

    public String signV0() {
        String method = "signV0";
        validateRequired();
        StringBuilder builder = buildCanonicalRequest();
        builder.append(String.format("%s=%s\n", ApiHeaders.X_ARROW_APIKEY, apiKey));
        builder.append(String.format("%s=%s", ApiHeaders.X_ARROW_DATE, timestamp));

        String stringToSign = builder.toString();
        logDebug(method, "stringToSign: %s\n", stringToSign);
        return HmacUtils.hmacSha256Hex(secretKey, stringToSign);
    }

    public String signV1() {
        String method = "signV1";
        validateRequired();

        StringBuilder builder = buildCanonicalRequest();
        builder.append(hash(payload));

        StringBuilder stringToSign = new StringBuilder();
        stringToSign.append(hash(builder.toString())).append('\n');
        stringToSign.append(apiKey).append('\n');
        stringToSign.append(timestamp).append('\n');
        stringToSign.append(ApiHeaders.X_ARROW_VERSION_1);
        logDebug(method, "stringToSign: %s\n", stringToSign);

        String signingKey = HmacUtils.hmacSha256Hex(ApiHeaders.X_ARROW_VERSION_1,
                HmacUtils.hmacSha256Hex(timestamp, HmacUtils.hmacSha256Hex(apiKey, secretKey)));

        return HmacUtils.hmacSha256Hex(signingKey, stringToSign.toString());
    }

    private void validateRequired() {
        Validate.notEmpty(apiKey, "apiKey is required");
        Validate.notEmpty(secretKey, "secretKey is required");
        Validate.notEmpty(timestamp, "timestamp is required");
    }

    private StringBuilder buildCanonicalRequest() {

        StringBuilder builder = new StringBuilder();

        // append method
        Validate.notEmpty(method, "method is empty");
        builder.append(method).append('\n');

        // append uri
        Validate.notEmpty(uri);
        builder.append(uri).append('\n');

        // append parameters
        if (parameters.size() > 0) {
            Collections.sort(parameters);
            parameters.forEach(p -> builder.append(p).append('\n'));
        }
        return builder;
    }

    private String hash(String value) {
        return DigestUtils.sha256Hex(value);
    }
}