[AVRO-2101] Issue with null default value

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Not A Problem
• Affects Version/s: 1.8.2
• Component/s: java

Environment

Java/IntelliJ/Maven

Docs Text

{
    "namespace": "fr.mediametrie.internet.pame.meter.avro",
    "type": "record",
    "name": "MobtabAvroHit",
    "fields": [
        {
            "name": "time_usec",
            "type": ["null", "string"],
            "default": null
        },
        {
            "name": "mobile_event_type",
            "type": ["null", "string"],
            "default": null
        },
        {
            "name": "panelist_info",
            "type": {
                "type": "record",
                "name": "MobtabAvroPanelistInfo",
                "fields": [
                    {
                        "name": "panel_id",
                        "type": ["null", "string"],
                        "default": null
                    },
                    {
                        "name": "panelist_id",
                        "type": ["null", "string"],
                        "default": null
                    },
                    {
                        "name": "household_id",
                        "type": ["null", "string"],
                        "default": null
                    }
                ]
            }
        },
        {
            "name": "device_info",
            "type": {
                "type": "record",
                "name": "MobtabAvroDeviceInfo",
                "fields": [
                    {
                        "name": "model_name",
                        "type": ["null", "string"],
                        "default": null
                    },
                    {
                        "name": "operating_system_name",
                        "type": ["null", "string"],
                        "default": null
                    },
                    {
                        "name": "operating_system_version",
                        "type": ["null", "string"],
                        "default": null
                    },
                    {
                        "name": "type",
                        "type": ["null", "string"],
                        "default": null
                    },
                    {
                        "name": "ad_id",
                        "type": ["null", "string"],
                        "default": null
                    }
                ]
            }
        },
        {
            "name": "mobile_web_event",
            "type": {
                "type": "record",
                "name": "MobtabAvroMobileWebEvent",
                "fields": [
                    {
                        "name": "url",
                        "type": ["null", "string"],
                        "default": null
                    },
                    {
                        "name": "user_agent",
                        "type": ["null", "string"],
                        "default": null
                    }
                ]
            }
        },
        {
            "name": "mobile_app_activity",
            "type": {
                "type": "record",
                "name": "MobtabAvroMobileAppActivity",
                "fields": [
                    {
                        "name": "app",
                        "type": ["null", "string"],
                        "default": null
                    },
                    {
                        "name": "start_time_usec",
                        "type": ["null", "string"],
                        "default": null
                    },
                    {
                        "name": "end_time_usec",
                        "type": ["null", "string"],
                        "default": null
                    }
                ]
            }
        }
    ]
}

• Assignee: Unassigned
• Reporter: Eddy ALBERT
• Created: 26/Oct/17 12:11
• Updated: 09/Nov/17 09:35
• Resolved: 08/Nov/17 12:08

Description

Hi,

It seems there is a bug in the Avro library when generating the Avro source files from the Avro schema.
As you could see in appendice, my schema is based on a main record and several sub-records.
I work with "unions" for the type definition to allow setting fields to null when the value is not present.

The issue is the following:
First of all, this behavior isn't deterministic!
When the library generates the source file, most of the sub-records are well generated (with null as the default value), but sometime, a single sub-record has its default value set to "null" (String). If I change the default value of the issued sub-record to "foo" and I re-generate the source file, I can see "foo" as the default value. If I rollback that change (back the default value to null) and I re-generate, I finally get null as default value (but not everytime ...).

I think this issue is the source bug of the one I publish on Stackoverflow (directly see my second post):
https://stackoverflow.com/questions/46775649/handle-nested-avro-record-when-the-one-is-null/46786313#46786313

Any suggestions?

Best regards,
EddyA.

Ps: its is always the same sub-record that is issued (mobile_web_event).