/**
* Copyright Microsoft Corporation
*
* 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.
*/
package com.microsoft.azure.storage;
import java.net.HttpURLConnection;
import java.util.Date;
import com.microsoft.azure.storage.core.BaseRequest;
import com.microsoft.azure.storage.core.Utility;
/**
* Represents a set of access conditions to be used for operations against the storage services.
*/
public final class AccessCondition {
/**
* Generates a new empty AccessCondition.
* <p>
* For more information, see <a href= 'http://go.microsoft.com/fwlink/?LinkID=224642'>Specifying Conditional Headers
* for Blob Service Operations</a>.
*
* @return An <code>AccessCondition</code> object that has no conditions set.
*/
public static AccessCondition generateEmptyCondition() {
return new AccessCondition();
}
/**
* Returns an access condition such that an operation will be performed only if the resource's ETag value matches
* the specified ETag value.
* <p>
* Setting this access condition modifies the request to include the HTTP <i>If-Match</i> conditional header. If
* this access condition is set, the operation is performed only if the ETag of the resource matches the specified
* ETag.
* <p>
* For more information, see <a href= 'http://go.microsoft.com/fwlink/?LinkID=224642'>Specifying Conditional Headers
* for Blob Service Operations</a>.
*
* @param etag
* A <code>String</code> that represents the ETag value to check.
*
* @return An <code>AccessCondition</code> object that represents the <i>If-Match</i> condition.
*/
public static AccessCondition generateIfMatchCondition(final String etag) {
AccessCondition retCondition = new AccessCondition();
retCondition.setIfMatch(etag);
return retCondition;
}
/**
* Returns an access condition such that an operation will be performed only if the resource has been modified since
* the specified time.
* <p>
* Setting this access condition modifies the request to include the HTTP <i>If-Modified-Since</i> conditional
* header. If this access condition is set, the operation is performed only if the resource has been modified since
* the specified time.
* <p>
* For more information, see <a href= 'http://go.microsoft.com/fwlink/?LinkID=224642'>Specifying Conditional Headers
* for Blob Service Operations</a>.
*
* @param lastMotified
* A <code>java.util.Date</code> object that represents the last-modified time to check for the resource.
*
* @return An <code>AccessCondition</code> object that represents the <i>If-Modified-Since</i> condition.
*/
public static AccessCondition generateIfModifiedSinceCondition(final Date lastMotified) {
AccessCondition retCondition = new AccessCondition();
retCondition.ifModifiedSinceDate = lastMotified;
return retCondition;
}
/**
* Returns an access condition such that an operation will be performed only if the resource's ETag value does not
* match the specified ETag value.
* <p>
* Setting this access condition modifies the request to include the HTTP <i>If-None-Match</i> conditional header.
* If this access condition is set, the operation is performed only if the ETag of the resource does not match the
* specified ETag.
* <p>
* For more information, see <a href= 'http://go.microsoft.com/fwlink/?LinkID=224642'>Specifying Conditional Headers
* for Blob Service Operations</a>.
*
* @param etag
* A <code>String</code> that represents the ETag value to check.
*
* @return An <code>AccessCondition</code> object that represents the <i>If-None-Match</i> condition.
*/
public static AccessCondition generateIfNoneMatchCondition(final String etag) {
AccessCondition retCondition = new AccessCondition();
retCondition.setIfNoneMatch(etag);
return retCondition;
}
/**
* Returns an access condition such that an operation will be performed only if the resource has not been modified
* since the specified time.
* <p>
* Setting this access condition modifies the request to include the HTTP <i>If-Unmodified-Since</i> conditional
* header. If this access condition is set, the operation is performed only if the resource has not been modified
* since the specified time.
* <p>
* For more information, see <a href= 'http://go.microsoft.com/fwlink/?LinkID=224642'>Specifying Conditional Headers
* for Blob Service Operations</a>.
*
* @param lastMotified
* A <code>java.util.Date</code> object that represents the last-modified time to check for the resource.
*
* @return An <code>AccessCondition</code> object that represents the <i>If-Unmodified-Since</i> condition.
*/
public static AccessCondition generateIfNotModifiedSinceCondition(final Date lastMotified) {
AccessCondition retCondition = new AccessCondition();
retCondition.ifUnmodifiedSinceDate = lastMotified;
return retCondition;
}
/**
* Returns an access condition such that an operation will be performed only if the resource is accessible under the
* specified lease ID.
* <p>
* For more information, see <a href= 'http://go.microsoft.com/fwlink/?LinkID=224642'>Specifying Conditional Headers
* for Blob Service Operations</a>.
*
* @param leaseID
* The lease ID to specify.
*
*/
public static AccessCondition generateLeaseCondition(final String leaseID) {
AccessCondition retCondition = new AccessCondition();
retCondition.leaseID = leaseID;
return retCondition;
}
private String leaseID = null;
/**
* Represents the ETag of the resource for if [none] match conditions
*/
private String etag = null;
/**
* Represents the date for ifModifiedSinceDate conditions.
*/
private Date ifModifiedSinceDate = null;
/**
* Represents the date for ifUnmodifiedSinceDate conditions.
*/
private Date ifUnmodifiedSinceDate = null;
/**
* Represents the ifMatchHeaderType type.
*/
private String ifMatchHeaderType = null;
/**
* Creates an instance of the <code>AccessCondition</code> class.
*/
public AccessCondition() {
// Empty default constructor.
}
/**
* RESERVED FOR INTERNAL USE. Applies the access condition to the request.
*
* @param request
* A <code>java.net.HttpURLConnection</code> object that represents the request to which the condition is
* being applied.
*
* @throws StorageException
* If there is an error parsing the date value of the access condition.
*/
public void applyConditionToRequest(final HttpURLConnection request) {
applyConditionToRequest(request, false);
}
/**
* RESERVED FOR INTERNAL USE. Applies the access condition to the request.
*
* @param request
* A <code>java.net.HttpURLConnection</code> object that represents the request to which the condition is
* being applied.
* @param useSourceAccessHeaders
* If true will use the Source_ headers for the conditions, otherwise standard headers are used.
* @throws StorageException
* If there is an error parsing the date value of the access condition.
*/
public void applyConditionToRequest(final HttpURLConnection request, boolean useSourceAccessHeaders) {
// When used as a source access condition
if (useSourceAccessHeaders) {
if (!Utility.isNullOrEmpty(this.leaseID)) {
request.setRequestProperty(Constants.HeaderConstants.SOURCE_LEASE_ID_HEADER, this.leaseID);
}
if (this.ifModifiedSinceDate != null) {
request.setRequestProperty(Constants.HeaderConstants.SOURCE_IF_MODIFIED_SINCE_HEADER,
Utility.getGMTTime(this.ifModifiedSinceDate));
}
if (this.ifUnmodifiedSinceDate != null) {
request.setRequestProperty(Constants.HeaderConstants.SOURCE_IF_UNMODIFIED_SINCE_HEADER,
Utility.getGMTTime(this.ifUnmodifiedSinceDate));
}
if (!Utility.isNullOrEmpty(this.etag)) {
if (this.ifMatchHeaderType.equals(Constants.HeaderConstants.IF_MATCH)) {
request.setRequestProperty(Constants.HeaderConstants.SOURCE_IF_MATCH_HEADER, this.etag);
}
// test
else if (this.ifMatchHeaderType.equals(Constants.HeaderConstants.IF_NONE_MATCH)) {
request.setRequestProperty(Constants.HeaderConstants.SOURCE_IF_NONE_MATCH_HEADER, this.etag);
}
}
}
else {
if (!Utility.isNullOrEmpty(this.leaseID)) {
BaseRequest.addLeaseId(request, this.leaseID);
}
if (this.ifModifiedSinceDate != null) {
request.setRequestProperty(Constants.HeaderConstants.IF_MODIFIED_SINCE,
Utility.getGMTTime(this.ifModifiedSinceDate));
}
if (this.ifUnmodifiedSinceDate != null) {
request.setRequestProperty(Constants.HeaderConstants.IF_UNMODIFIED_SINCE,
Utility.getGMTTime(this.ifUnmodifiedSinceDate));
}
if (!Utility.isNullOrEmpty(this.etag)) {
request.setRequestProperty(this.ifMatchHeaderType, this.etag);
}
}
}
/**
* Gets the ETag when the <i>If-Match</i> condition is set.
*
* @return The ETag when the <i>If-Match</i> condition is set; otherwise, null.
*/
public String getIfMatch() {
return this.ifMatchHeaderType.equals(Constants.HeaderConstants.IF_MATCH) ? this.etag : null;
}
/**
* Gets the <i>If-Modified-Since</i> date.
*
* @return A <code>java.util.Date</code> object that represents the <i>If-Modified-Since</i> date.
*/
public Date getIfModifiedSinceDate() {
return this.ifModifiedSinceDate;
}
/**
* Gets the ETag when the If-None-Match condition is set.
*
* @return The ETag when the If-None-Match condition is set; otherwise, null.
*/
public String getIfNoneMatch() {
return this.ifMatchHeaderType.equals(Constants.HeaderConstants.IF_NONE_MATCH) ? this.etag : null;
}
/**
* Gets the <i>If-Unmodified-Since</i> date.
*
* @return A <code>java.util.Date</code> object that represents the <i>If-Unmodified-Since</i> date.
*/
public Date getIfUnmodifiedSinceDate() {
return this.ifUnmodifiedSinceDate;
}
/**
* Gets the lease ID.
*
* @return The lease ID.
*/
public String getLeaseID() {
return this.leaseID;
}
/**
* Sets the ETag for the <i>If-Match</i> condition.
*
* @param etag
* The ETag to set for the <i>If-Match</i> condition.
*/
public void setIfMatch(String etag) {
this.etag = normalizeEtag(etag);
this.ifMatchHeaderType = Constants.HeaderConstants.IF_MATCH;
}
/**
* Sets the <i>If-Modified-Since</i> date.
*
* @param ifModifiedSinceDate
* A <code>java.util.Date</code> object that represents the <i>If-Modified-Since</i> to set.
*/
public void setIfModifiedSinceDate(Date ifModifiedSinceDate) {
this.ifModifiedSinceDate = ifModifiedSinceDate;
}
/**
* Sets the ETag for the <i>If-None-Match</i> condition.
*
* @param etag
* The ETag to set for the <i>If-None-Match</i> condition.
*/
public void setIfNoneMatch(String etag) {
this.etag = normalizeEtag(etag);
this.ifMatchHeaderType = Constants.HeaderConstants.IF_NONE_MATCH;
}
/**
* Sets the <i>If-Unmodified-Since</i> date.
*
* @param ifUnmodifiedSinceDate
* A <code>java.util.Date</code> object that represents the <i>If-Unmodified-Since</i> to set.
*/
public void setIfUnmodifiedSinceDate(Date ifUnmodifiedSinceDate) {
this.ifUnmodifiedSinceDate = ifUnmodifiedSinceDate;
}
/**
* Gets the lease ID.
*
* @param leaseID
* The lease ID to set.
*/
public void setLeaseID(String leaseID) {
this.leaseID = leaseID;
}
/**
* Reserved for internal use. Verifies the condition is satisfied.
*
* @param etag
* A <code>String</code> that represents the ETag to check.
* @param lastModified
* A <code>java.util.Date</code> object that represents the last modified date/time.
*
* @return <code>true</code> if the condition is satisfied; otherwise, <code>false</code>.
*
*/
public boolean verifyConditional(final String etag, final Date lastModified) {
if (this.ifModifiedSinceDate != null) {
// The IfModifiedSince has a special helper in HttpURLConnection, use it instead of manually setting the
// header.
if (!lastModified.after(this.ifModifiedSinceDate)) {
return false;
}
}
if (this.ifUnmodifiedSinceDate != null) {
if (lastModified.after(this.ifUnmodifiedSinceDate)) {
return false;
}
}
if (!Utility.isNullOrEmpty(this.etag)) {
if (this.ifMatchHeaderType.equals(Constants.HeaderConstants.IF_MATCH)) {
if (!this.etag.equals(etag) && !this.etag.equals("*")) {
return false;
}
}
else if (this.ifMatchHeaderType.equals(Constants.HeaderConstants.IF_NONE_MATCH)) {
if (this.etag.equals(etag)) {
return false;
}
}
}
return true;
}
/**
* Normalizes an ETag to be quoted, unless it is *.
*
* @param inTag
* The ETag to normalize.
* @return The quoted ETag.
*/
private static String normalizeEtag(String inTag) {
if (Utility.isNullOrEmpty(inTag) || inTag.equals("*")) {
return inTag;
}
else if (inTag.startsWith("\"") && inTag.endsWith("\"")) {
return inTag;
}
else {
return String.format("\"%s\"", inTag);
}
}
}