API Stability Long-Term

The createParserV2() GraphQL mutation may be used to create a parser in LogScale.

To update or otherwise change a parser, use the updateParserV2() mutation. You can use testParserV2() to test a parser and deleteParserV2() to delete one.

Similar to this mutation, there is the cloneParser() mutation to copy a parser instead of creating one. You can modify the new ones to your requirements. There's also the createParserFromPackageTemplate() mutation for creating a parser from a package and createParserFromTemplate() for creating one from a template.

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Show Parsers Query

For more information on creating a parser, see the Custom Parsers documentation page. You may also want to look at the Parse Data and Parsing Log Data pages for related information.

Syntax

graphql
createParserV2(
      input: CreateParserInputV2!
   ): Parser!

Example

Below is an example of how this mutation field might be used:

Raw
graphql
mutation {
  createParserV2(input:
      { repositoryName: "humio",
        name: "myKvParser",
        script: "kvParse()",
        testCases: [{
          event: {rawString: "key=value"}, 
          outputAssertions: [{outputEventIndex: 0, assertions: {fieldsHaveValues: [{fieldName: "key", expectedValue: "value"}]}}],
        }],
        fieldsToTag: [],
        fieldsToBeRemovedBeforeParsing: []
      })
  { id }
}
Mac OS or Linux (curl)
shell
curl -v -X POST $YOUR_LOGSCALE_URL/graphql \
    -H "Authorization: Bearer $TOKEN" \
    -H "Content-Type: application/json" \
    -d @- << EOF
{"query" : "mutation {
  createParserV2(input:
      { repositoryName: \"humio\",
        name: \"myKvParser\",
        script: \"kvParse()\",
        testCases: [{
          event: {rawString: \"key=value\"}, 
          outputAssertions: [{outputEventIndex: 0, assertions: {fieldsHaveValues: [{fieldName: \"key\", expectedValue: \"value\"}]}}],
        }],
        fieldsToTag: [],
        fieldsToBeRemovedBeforeParsing: []
      })
  { id }
}"
}
EOF
Mac OS or Linux (curl) One-line
shell
curl -v -X POST $YOUR_LOGSCALE_URL/graphql \
    -H "Authorization: Bearer $TOKEN" \
    -H "Content-Type: application/json" \
    -d @- << EOF
{"query" : "mutation {
  createParserV2(input:
      { repositoryName: \"humio\",
        name: \"myKvParser\",
        script: \"kvParse()\",
        testCases: [{
          event: {rawString: \"key=value\"}, 
          outputAssertions: [{outputEventIndex: 0, assertions: {fieldsHaveValues: [{fieldName: \"key\", expectedValue: \"value\"}]}}],
        }],
        fieldsToTag: [],
        fieldsToBeRemovedBeforeParsing: []
      })
  { id }
}"
}
EOF
Windows Cmd and curl
shell
curl -v -X POST $YOUR_LOGSCALE_URL/graphql ^
    -H "Authorization: Bearer $TOKEN" ^
    -H "Content-Type: application/json" ^
    -d @'{"query" : "mutation { ^
  createParserV2(input: ^
      { repositoryName: \"humio\", ^
        name: \"myKvParser\", ^
        script: \"kvParse()\", ^
        testCases: [{ ^
          event: {rawString: \"key=value\"},  ^
          outputAssertions: [{outputEventIndex: 0, assertions: {fieldsHaveValues: [{fieldName: \"key\", expectedValue: \"value\"}]}}], ^
        }], ^
        fieldsToTag: [], ^
        fieldsToBeRemovedBeforeParsing: [] ^
      }) ^
  { id } ^
}" ^
} '
Windows Powershell and curl
powershell
curl.exe -X POST 
    -H "Authorization: Bearer $TOKEN"
    -H "Content-Type: application/json"
    -d '{"query" : "mutation {
  createParserV2(input:
      { repositoryName: \"humio\",
        name: \"myKvParser\",
        script: \"kvParse()\",
        testCases: [{
          event: {rawString: \"key=value\"}, 
          outputAssertions: [{outputEventIndex: 0, assertions: {fieldsHaveValues: [{fieldName: \"key\", expectedValue: \"value\"}]}}],
        }],
        fieldsToTag: [],
        fieldsToBeRemovedBeforeParsing: []
      })
  { id }
}"
}'
    "$YOUR_LOGSCALE_URL/graphql"
Perl
perl
#!/usr/bin/perl

use HTTP::Request;
use LWP;

my $TOKEN = "TOKEN";

my $uri = '$YOUR_LOGSCALE_URL/graphql';

my $query = "mutation {
  createParserV2(input:
      { repositoryName: \"humio\",
        name: \"myKvParser\",
        script: \"kvParse()\",
        testCases: [{
          event: {rawString: \"key=value\"}, 
          outputAssertions: [{outputEventIndex: 0, assertions: {fieldsHaveValues: [{fieldName: \"key\", expectedValue: \"value\"}]}}],
        }],
        fieldsToTag: [],
        fieldsToBeRemovedBeforeParsing: []
      })
  { id }
}";
$query =~ s/\n/ /g;
my $json = sprintf('{"query" : "%s"}',$query);
my $req = HTTP::Request->new("POST", $uri );

$req->header("Authorization" => "Bearer $TOKEN");
$req->header("Content-Type" => "application/json");

$req->content( $json );

my $lwp = LWP::UserAgent->new;

my $result = $lwp->request( $req );

print $result->{"_content"},"\n";
Python
python
#! /usr/local/bin/python3

import requests

url = '$YOUR_LOGSCALE_URL/graphql'
mydata = r'''{"query" : "mutation {
  createParserV2(input:
      { repositoryName: \"humio\",
        name: \"myKvParser\",
        script: \"kvParse()\",
        testCases: [{
          event: {rawString: \"key=value\"}, 
          outputAssertions: [{outputEventIndex: 0, assertions: {fieldsHaveValues: [{fieldName: \"key\", expectedValue: \"value\"}]}}],
        }],
        fieldsToTag: [],
        fieldsToBeRemovedBeforeParsing: []
      })
  { id }
}"
}'''

resp = requests.post(url,
                     data = mydata,
                     headers = {
   "Authorization" : "Bearer $TOKEN",
   "Content-Type" : "application/json"
}
)

print(resp.text)
Node.js
javascript
const https = require('https');

const data = JSON.stringify(
    {"query" : "mutation {
  createParserV2(input:
      { repositoryName: \"humio\",
        name: \"myKvParser\",
        script: \"kvParse()\",
        testCases: [{
          event: {rawString: \"key=value\"}, 
          outputAssertions: [{outputEventIndex: 0, assertions: {fieldsHaveValues: [{fieldName: \"key\", expectedValue: \"value\"}]}}],
        }],
        fieldsToTag: [],
        fieldsToBeRemovedBeforeParsing: []
      })
  { id }
}"
}
);


const options = {
  hostname: '$YOUR_LOGSCALE_URL',
  path: 'graphql',
  port: 443,
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    'Content-Length': data.length,
    Authorization: 'BEARER ' + process.env.TOKEN,
    'User-Agent': 'Node',
  },
};

const req = https.request(options, (res) => {
  let data = '';
  console.log(`statusCode: ${res.statusCode}`);

  res.on('data', (d) => {
    data += d;
  });
  res.on('end', () => {
    console.log(JSON.parse(data).data);
  });
});

req.on('error', (error) => {
  console.error(error);
});

req.write(data);
req.end();

Given Datatype

For this input datatype, you would provide the name of the repository where the parser will be located, the parser script to execute for each event, any fields not to parse, and some other factors. These are listed and explained, along with other parameters, in the table below:

Table: CreateParserInputV2

ParameterTypeRequiredDefaultStabilityDescription
Some arguments may be required, as indicated in the Required column. For return datatypes, this indicates that you must specify which fields you want returned in the results.
Table last updated: Mar 28, 2025
allowOverwritingExistingParserboolean falseLong-TermAllows saving a parser with a name that is already in use, by overwriting the parser that previously had the name.
fieldsToTag[string]yes Long-TermFields that are used as tags.
fieldsToBeRemovedBeforeParsing[string]yes Long-TermA list of fields that will be removed from the event before it's parsed. These fields will not be included when calculating usage.
languageVersionLanguageVersionInputType {name: ”legacy“}Long-TermA specific language version. See LanguageVersionInputType.
namestringyes Long-TermThe name to use for the parser.
repositoryNameRepoOrViewNameyes Long-TermThe repository where the parser is located. RepoOrViewName is a scalar.
scriptstringyes Long-TermThe parser script that is executed for every incoming event.
testCases[ParserTestCaseInput]yes Long-TermTest cases that can be used to help verify that the parser works as expected. See ParserTestCaseInput.

Returned Datatype

With this returned datatype, you can get the fields that will be removed from events, a template for recreating the parser, and other information. Of course, having just created the parser with this mutation, you may only want the unique identifier assigned to it to use with other mutations and queries.

Table: Parser

ParameterTypeRequiredDefaultStabilityDescription
Some arguments may be required, as indicated in the Required column. For return datatypes, this indicates that you must specify which fields you want returned in the results.
Table last updated: Sep 30, 2025
createdInfoAssetCommitMetadata  Long-TermMetadata related to the creation of the parser. See AssetCommitMetadata.
descriptionstring  Long-TermA description of the parser.
displayNamestringyes Long-TermThe full name of the parser, including package information if part of an application.
fieldsToBeRemovedBeforeParsing[string]yes Long-TermA list of fields that will be removed from the event before it's parsed. These fields will not be included when calculating usage.
fieldsToTag[string]yes Long-TermThe fields that are used as tags.
idstringyes Long-TermThe unique identifier of the parser.
isBuiltInbooleanyes Long-TermTrue if the parser is one of LogScale's built-in parsers.
isOverriddenbooleanyes PreviewTrue if the parser is one of LogScale's built-in parsers, and it is overridden by a custom parser.
languageVersionLanguageVersionyes Long-TermThe language version used by the parser. See LanguageVersion.
modifiedInfoAssetCommitMetadata  Long-TermMetadata related to the latest modification of the parser. See AssetCommitMetadata.
namestringyes Long-TermThe name of the parser.
originDisplayStringstringyes PreviewThe origin of a parser. Can either be "Built in", "Local" or a package.
overridesBuiltInParserbooleanyes PreviewTrue if the parser is overrides one of LogScale's built-in parsers.
packagePackageInstallation  Long-TermThe package associated with the parser, if any. See PackageInstallation.
packageIdVersionedPackageSpecifier  Long-TermThe identifier of the package used, if one. VersionedPackageSpecifier is a scalar.
scriptstringyes Long-TermThe parser script that is executed for every incoming event.
testCases[ParserTestCase]yes Long-TermTest cases that can be used to help verify that the parser works as expected. See ParserTestCase.
yamlTemplateYAMLyes Long-TermA template that can be used to recreate the parser. YAML is a scalar.