我parsing通过日志文件并获得结果行（使用grep），如下所示：
2017-01-26 17:19:40 +0000 docker: {"source":"stdout","log":"I, [2017-01-26T17:19:40.703988 #24] INFO -- : {\"tags\":\"structured_log\",\"payload\":{\"results\":[{\"baserate\":\"-1\"}]},\"commit_stamp\":1485451180,\"resource\":\"google_price_result_metric\",\"object_id\":\"20170126171940700\"}","container_id":"6ecbf7f64e4c9557e9dd1efbc6666a3c6c53f9cd5c18414ed5633cad8c302e","container_name":"/test-container-b49c8188c3ebe4b93300"} 2017-01-26 17:19:40 +0000 docker: {"container_id":"6ecbf7f64e4c9557e9dd1efbc6666a3c6c53f9cd5c18414ed5633cad8c302e","container_name":"/test-container-b49c8188c3ebe4b93300","source":"stdout","log":"I, [2017-01-26T17:19:40.704364 #24] INFO -- : method=POST path=/prices.xml format=xml controller=TestController action=prices status=200 duration=1686.51 view=0.08 db=0.62"} 然后使用以下命令提取JSON对象：
... | grep -o -E "\{.*$"
我知道我可以用python -mjson.toolparsing一行python -mjson.tool如下所示：
... | grep -o -E "\{.*$" | tail -n1 | python -mjson.tool
但是我想parsing两行（或者n行）。 我怎样才能在bash中做到这一点？ （我认为xargs应该让我这样做，但是我对这个工具很陌生，无法弄清楚）
jq可以被告知接受纯文本作为输入，并尝试将提取的子集解析为JSON。 考虑下面的例子，用jq 1.5进行测试：
jq -R 'capture("docker: (?<json>[{].*[}])$") | .json? | select(.) | fromjson' <<'EOF' 2017-01-26 17:19:40 +0000 docker: {"source":"stdout","log":"I, [2017-01-26T17:19:40.703988 #24] INFO -- : {\"tags\":\"structured_log\",\"payload\":{\"results\":[{\"baserate\":\"-1\"}]},\"commit_stamp\":1485451180,\"resource\":\"google_price_result_metric\",\"object_id\":\"20170126171940700\"}","container_id":"6ecbf7f64e4c9557e9dd1efbc6666a3c6c53f9cd5c18414ed5633cad8c302e","container_name":"/test-container-b49c8188c3ebe4b93300"} 2017-01-26 17:19:40 +0000 docker: {"container_id":"6ecbf7f64e4c9557e9dd1efbc6666a3c6c53f9cd5c18414ed5633cad8c302e","container_name":"/test-container-b49c8188c3ebe4b93300","source":"stdout","log":"I, [2017-01-26T17:19:40.704364 #24] INFO -- : method=POST path=/prices.xml format=xml controller=TestController action=prices status=200 duration=1686.51 view=0.08 db=0.62"} EOF
…适当地产生：
{ "source": "stdout", "log": "I, [2017-01-26T17:19:40.703988 #24] INFO -- : {\"tags\":\"structured_log\",\"payload\":{\"results\":[{\"baserate\":\"-1\"}]},\"commit_stamp\":1485451180,\"resource\":\"google_price_result_metric\",\"object_id\":\"20170126171940700\"}", "container_id": "6ecbf7f64e4c9557e9dd1efbc6666a3c6c53f9cd5c18414ed5633cad8c302e", "container_name": "/test-container-b49c8188c3ebe4b93300" } { "container_id": "6ecbf7f64e4c9557e9dd1efbc6666a3c6c53f9cd5c18414ed5633cad8c302e", "container_name": "/test-container-b49c8188c3ebe4b93300", "source": "stdout", "log": "I, [2017-01-26T17:19:40.704364 #24] INFO -- : method=POST path=/prices.xml format=xml controller=TestController action=prices status=200 duration=1686.51 view=0.08 db=0.62" }