原文网址：https://www.youyong.top/article/1158e723d9120
AliyunCLI支持使用filter参数对指令返回的结果进行过滤输出。从开放API调用返回数据, 默认采用Json格式，所以用户在使用AliyunCLI时, 可以根据Json的特点, 使用过滤功能直接获取所需子节点数据。
下面举例说明：
原文网址：https://www.youyong.top/article/1158e723d9120
原始数据：
# aliyuncli ecs DescribeImages --ImageOwnerAlias system --output json --PageSize 1 --PageNumber 1 { "PageSize": 1, "RegionId": "cn-hangzhou", "TotalCount": 39, "PageNumber": 1, "RequestId": "A0F91B21-BD8D-48D9-9EC8-36FB7E1D387E", "Images": { "Image": [ { "Status": "Available", "ProductCode": "", "Platform": "Freebsd", "Description": "freebsd1001_64_20G_aliaegis_20150527.vhd", "IsCopied": false, "Tags": { "Tag": [] }, "IsSubscribed": false, "IsSelfShared": "", "CreationTime": "2015-06-19T10:45:56Z", "OSName": "FreeBSD 10.1 64\u4f4d", "DiskDeviceMappings": { "DiskDeviceMapping": [ { "Format": "", "ImportOSSBucket": "", "Device": "/dev/xvda", "SnapshotId": "", "ImportOSSObject": "", "Size": "20" } ] }, "ImageId": "freebsd1001_64_20G_aliaegis_20150527.vhd", "Usage": "instance", "ImageName": "freebsd1001_64_20G_aliaegis_20150527.vhd", "Architecture": "x86_64", "ImageOwnerAlias": "system", "OSType": "linux", "Progress": "100%", "ImageVersion": "1.0.0", "Size": 20 } ] } } |
用法示例：
示例1：指定key值进行过滤，获取对应value
如果通过filter传入的key值是最末节点，则会返回其对应的value。
过滤方法示例
只过滤输出返回结果中的TotalCount字段对应值：
# aliyuncli ecs DescribeImages --ImageOwnerAlias system --output json --PageSize 1 --PageNumber 1 --filter TotalCount 39 |
示例2：指定key值进行过滤，获取所有子节点数据
如果通过filter传入的key值非最末节点，则会返回其下所有子节点数据。
过滤方法示例
过滤输出返回结果中所有Image相关信息：
# aliyuncli ecs DescribeImages --ImageOwnerAlias system --output json --PageSize 1 --PageNumber 1 --filter Images { "Image": [ { "Status": "Available", "ProductCode": "", "Platform": "Freebsd", "Description": "freebsd1001_64_20G_aliaegis_20150527.vhd", "IsCopied": false, "Tags": { "Tag": [] }, "IsSubscribed": false, "IsSelfShared": "", "CreationTime": "2015-06-19T10:45:56Z", "OSName": "FreeBSD 10.1 64\u4f4d", "DiskDeviceMappings": { "DiskDeviceMapping": [ { "Format": "", "ImportOSSBucket": "", "Device": "/dev/xvda", "SnapshotId": "", "ImportOSSObject": "", "Size": "20" } ] }, "ImageId": "freebsd1001_64_20G_aliaegis_20150527.vhd", "Usage": "instance", "ImageName": "freebsd1001_64_20G_aliaegis_20150527.vhd", "Architecture": "x86_64", "ImageOwnerAlias": "system", "OSType": "linux", "Progress": "100%", "ImageVersion": "1.0.0", "Size": 20 } ] } |
示例3：通过数组下标获取返回数组（array）中指定子项值
如果返回结果中包含数组（array）数据，则可以通过filter传入指定序列编号获取相应子项值。
注意：数组下标从0开始计数。
过滤方法示例
过滤输出返回结果中第1个Image的所有相关信息：
# aliyuncli ecs DescribeImages --ImageOwnerAlias system --output json --PageSize 1 --PageNumber 1 --filter Images.Image[0] { "Status": "Available", "ProductCode": "", "Platform": "Freebsd", "Description": "freebsd1001_64_20G_aliaegis_20150527.vhd", "IsCopied": false, "Tags": { "Tag": [] }, "IsSubscribed": false, "IsSelfShared": "", "CreationTime": "2015-06-19T10:45:56Z", "OSName": "FreeBSD 10.1 64\u4f4d", "DiskDeviceMappings": { "DiskDeviceMapping": [ { "Format": "", "ImportOSSBucket": "", "Device": "/dev/xvda", "SnapshotId": "", "ImportOSSObject": "", "Size": "20" } ] }, "ImageId": "freebsd1001_64_20G_aliaegis_20150527.vhd", "Usage": "instance", "ImageName": "freebsd1001_64_20G_aliaegis_20150527.vhd", "Architecture": "x86_64", "ImageOwnerAlias": "system", "OSType": "linux", "Progress": "100%", "ImageVersion": "1.0.0", "Size": 20 } |
示例4：通过数组下标获取返回数组（array）子项下指定字段对应值
如果返回结果中包含数组（array）数据，则可以通过filter传入指定序列编号和所需字段，获取相应子项下所需字段值。
注意：数组下标从0开始计数。
过滤方法示例
过滤输出返回结果中第1个Image的ImageId值：
# aliyuncli ecs DescribeImages --ImageOwnerAlias system --output json --PageSize 1 --PageNumber 1 --filter Images.Image[0].ImageId "freebsd1001_64_20G_aliaegis_20150527.vhd" |
示例5：通过*号获取返回数组（array）中所有子项下指定字段对应值
如果返回结果中包含数组（array）数据，则可以通过filter传入*号和所需字段，获取所有子项下所需字段值。
过滤方法示例
过滤输出返回结果中所有ImageId值：
# aliyuncli ecs DescribeImages --ImageOwnerAlias system --output json --PageSize 1 --PageNumber 1 --filter Images.Image[*].ImageId [ "freebsd1001_64_20G_aliaegis_20150527.vhd" ] |
示例6：嵌套过滤
如果返回结果中包含的数组（array）数据的子节点也是数组，则可以通过嵌套过滤获取所需子项下的所需字段值。
过滤方法示例
过滤输出返回结果中指定编号Image的所生成磁盘的Device信息：
# aliyuncli ecs DescribeImages --ImageOwnerAlias system --output json --PageSize 1 --PageNumber 1 --filter Images.Image[0].DiskDeviceMappings.DiskDeviceMapping[0].Device "/dev/xvda" |
