如何使用sed编辑json中的值

Question

I have the following json file:

"environment": [
        {
          "name": "DD_AGENT_HOST",
          "value": "somevalue.com"
        },
        {
          "name": "DD_AGENT_PORT",
          "value": "1234"
        },
        {
          "name": "DD_TRACE_SPAN_TAGS",
          "value": "env:test"
        },
        {
          "name": "JAVA_OPTS",
          "value": "-javaagent:/dd-java-agent/dd-java-agent.jar -Xms512m -Xmx2548m -XX:MaxPermSize=512m -Dspring.profiles.active=testapp -Dspring.cloud.config.label=<some value> -Duser.timezone=America/New_York"
        }

I am trying to change a particular parameter in value for key "JAVA_OPTS". This is a part of Jenkins job,

This is what I am trying to achieve, is to be able to change the value for parameter ${Config_Label} -Dspring.cloud.config.label=${Config_Label}

And I have tried this solution which does not seem to work:

sed -i "/value/c\   \"value\" : \"-javaagent:/dd-java-agent/dd-java-agent.jar -Xms512m -Xmx2548m -XX:MaxPermSize=512m -Dspring.profiles.active=testapp -Dencrypt.key=bjb4343knwdc -Dspring.cloud.config.label=${Config_Label} -Duser.timezone=America/New_York"\"," file.json

But the syntax doesn't work and the Jenkins job fails with error

unexpected EOF while looking for matching `"'

Hoping someone could correct me here. Thank you.

Answer 1

When modifying objects in jq, all it takes really is:

1. Find the object you want to update

    # the environment object with the name "JAVA_OPTS" .environment[] | select(.name == "JAVA_OPTS") 

2. Assign a new value to the property you want updated

    # update the value property using (= or |=) .environment[] | select(.name == "JAVA_OPTS").value = ... 

At this point, it's just a question of, updating a string to replace with something else. You can use a regular expression to do the replacement or any other replacement approach you'd like:

sub("(?<k>-Dspring\\.cloud\\.config\\.label)=<some value>"; "\(.k)=${Config_Label}")

Putting that all together:

.environment[] | select(.name == "JAVA_OPTS").value
    |= sub("(?<k>-Dspring\\.cloud\\.config\\.label)=<some value>"; "\(.k)=${Config_Label}")

Answer 2

Use the ' to enclose the sed script, in order to avoid escaping " . Your goal is to search for JAVA_OPTS , and then modify the string in the line after.

I always have this super tutorial open aside in order to help: Sed - An Introduction and Tutorial by Bruce Barnett

N : this sed command reads the next line in the file and happends it to the pattern buffer.

The example below is doing the trick but this is going to break easily when the json data vary; it is recommended to use jq as @Iniam suggested.

If you still want to have something working for the example in your question, give a try to this:

sed -i '/"name"[[:blank:]]*:[[:blank:]]*"JAVA_OPTS"[[:blank:]]*,/ { N ; s/-Dspring.cloud.config.label=\(.*\) -Duser/-Dspring.cloud.config.label=${Config_Label} -Duser/ ; }' file.json

Same version on several lines:

sed -i '/"name"[[:blank:]]*:[[:blank:]]*"JAVA_OPTS"[[:blank:]]*,/ {
    N
    s/-Dspring.cloud.config.label=\(.*\) -Duser/-Dspring.cloud.config.label=${Config_Label} -Duser/
} ' file.json

Answer 3

You could also do this with a simple Node script as well. If the shell environment variable is, say VERSION, you could use the following script for this replacement, as well as other possible manipulations of the file for the build process you might be running:

#!/usr/bin/env node
// replace.js
const chunks = [];

process.stdin.resume();
process.stdin.setEncoding('utf8');

process.stdin.on('data', (chunk) => {
    chunks.push(chunk);
});

process.stdin.on('end', () => {
    const json = JSON.parse(chunks.join(''));

    // Process json.environment array
    json.environment = json.environment.map(obj => {
        if (obj.name == 'JAVA_OPTS') {
                obj.value = obj.value.replace(/(-Dspring.cloud.config.label=)([^\s]+)/, `$1${process.env.VERSION}`);
        }
        return obj;
    });

    process.stdout.write(JSON.stringify(json, null, 2));
    process.stdout.write('\n');
});

You can then run it like:

$ VERSION=v6.7 ./replace.js < YOURFILE.json

Answer 4

If the file contains Dspring.cloud.config.label only once

You can directly use this:

 sed 's/Dspring.cloud.config.label=\S*/Dspring.cloud.config.label=${Config_Label}/g' json

if you want to commit this change into your put -i after sed

but if Dspring.cloud.config.label string comes multiple times please share more details of file.

Answer 5

Since

Dspring.cloud.config.label

was occurring only once in the json file, I have made use of sed function as mentioned by one of the users (Mohit Rathore). This may not be an exceptional solution, but it was simple and it worked in this use case.

sed -i "s/Dspring.cloud.config.label=\S*/Dspring.cloud.config.label=${Config_Label}/g" file.json 

Thank you.