Hi,

Just in case this helps somebody! It tooks quite a bit of time to track this issue down.

We've had an issue with the sfdx force:data:tree:import command failing with a MALFORMED_ID message when trying to resolve references during data imports.   It turns out the issue was realated to our namespace, which has numbers in it, which the sfdx tool didn't handle.  
 
An example is :-

plan.json
 

[
    {
        "sobject": "i42as__testParent",
        "saveRefs": true,
        "files": [
            "parent.json"
        ]
    },
    {
        "sobject": "i42as__testChild",
        "resolveRefs": true,
        "files": [
            "child.json"
        ]
    }
]

parent.json 
 

{
    "records": [
        {
            "attributes": {
                "type": "i42as__testParent__c",
                "referenceId": "parentRef1"
            },
            "i42as__Message": "Hello"
        }
    ]
}

child.json

{
    "records": [{
        "attributes": {
            "type": "i42as__testChild__c",
            "referenceId": "testChildRef1"
        },
        "i42as__parent__c": "@parentRef1"
    }]
}

When run with the following command, this returns an error.  
 

sfdx  force:data:tree:import --plan plan.json

STATUSCODE    MESSAGE                                                                    FIELDS
────────────  ─────────────────────────────────────────────────────────────────────────  ───────────────────────────
MALFORMED_ID  Object: id value of incorrect type: @parentRef1  i42as__parent__c
=== testChildRef1 [1]

In turns out this was an error in the salesforce-alm library, the regex used to look for the @parentRef1 replacement was not expecting a number in the namespace.  I've managed to work around the issue by changing the file .local/share/sfdx/client/node_modules/salesforce-alm/dist/lib/data/dataImportApi.js as follows;-
 

const jsonRefRegex = /[.]*["|'][A-Z_]*["|'][ ]*:[ ]*["|']@([A-Z0-9_]*)["|'][.]*/igm;
const jsonRefRegex = /[.]*["|'][0-9A-Z_]*["|'][ ]*:[ ]*["|']@([A-Z0-9_]*)["|'][.]*/igm;

 

Hi,

Just in case this helps somebody! It tooks quite a bit of time to track this issue down.

We've had an issue with the sfdx force:data:tree:import command failing with a MALFORMED_ID message when trying to resolve references during data imports.   It turns out the issue was realated to our namespace, which has numbers in it, which the sfdx tool didn't handle.  
 
An example is :-

plan.json
 

[
    {
        "sobject": "i42as__testParent",
        "saveRefs": true,
        "files": [
            "parent.json"
        ]
    },
    {
        "sobject": "i42as__testChild",
        "resolveRefs": true,
        "files": [
            "child.json"
        ]
    }
]

parent.json 
 

{
    "records": [
        {
            "attributes": {
                "type": "i42as__testParent__c",
                "referenceId": "parentRef1"
            },
            "i42as__Message": "Hello"
        }
    ]
}

child.json

{
    "records": [{
        "attributes": {
            "type": "i42as__testChild__c",
            "referenceId": "testChildRef1"
        },
        "i42as__parent__c": "@parentRef1"
    }]
}

When run with the following command, this returns an error.  
 

sfdx  force:data:tree:import --plan plan.json

STATUSCODE    MESSAGE                                                                    FIELDS
────────────  ─────────────────────────────────────────────────────────────────────────  ───────────────────────────
MALFORMED_ID  Object: id value of incorrect type: @parentRef1  i42as__parent__c
=== testChildRef1 [1]

In turns out this was an error in the salesforce-alm library, the regex used to look for the @parentRef1 replacement was not expecting a number in the namespace.  I've managed to work around the issue by changing the file .local/share/sfdx/client/node_modules/salesforce-alm/dist/lib/data/dataImportApi.js as follows;-
 

const jsonRefRegex = /[.]*["|'][A-Z_]*["|'][ ]*:[ ]*["|']@([A-Z0-9_]*)["|'][.]*/igm;
const jsonRefRegex = /[.]*["|'][0-9A-Z_]*["|'][ ]*:[ ]*["|']@([A-Z0-9_]*)["|'][.]*/igm;