> ## Documentation Index
> Fetch the complete documentation index at: https://doc.lucidworks.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Legacy Item Recommender Jobs

export const schema = {
  "type": "object",
  "title": "Legacy Item Recommender",
  "description": "Use this job when you want to compute user recommendations based on pre-computed item similarities.",
  "required": ["id", "trainingCollection", "itemSimCollection", "outputRecsCollection", "type"],
  "properties": {
    "id": {
      "type": "string",
      "title": "Spark Job ID",
      "description": "The ID for this Spark job. Used in the API to reference this job. Allowed characters: a-z, A-Z, dash (-) and underscore (_)",
      "maxLength": 128,
      "pattern": "^[A-Za-z0-9_\\-]+$"
    },
    "trainingCollection": {
      "type": "string",
      "title": "Preference Collection",
      "description": "User/Item preference collection (often a signals collection or signals aggregation collection)"
    },
    "itemSimCollection": {
      "type": "string",
      "title": "Item Similarity Collection",
      "description": "Collection containing item-to-item similarity values (computed by any means)"
    },
    "outputRecsCollection": {
      "type": "string",
      "title": "Output Recommendations Collection",
      "description": "Collection containing item-to-item similarity-based recommendations "
    },
    "trainingDataFilterQuery": {
      "type": "string",
      "title": "Preference Collection Filter Query",
      "description": "Solr query to filter user preferences",
      "default": "*:*",
      "hints": ["advanced"]
    },
    "prefUserIdField": {
      "type": "string",
      "title": "Preference Collection User Id Field",
      "description": "Solr field name containing stored user ids in the preference collection",
      "default": "user_id_s",
      "hints": ["advanced"]
    },
    "prefItemIdField": {
      "type": "string",
      "title": "Preference Collection Item Id Field",
      "description": "Solr field name containing stored item ids in the preference collection",
      "default": "item_id_s",
      "hints": ["advanced"]
    },
    "prefWeightField": {
      "type": "string",
      "title": "Preference Collection Preference Weight Field",
      "description": "Solr field name containing preference weight in the preferences collection",
      "default": "weight_d",
      "hints": ["advanced"]
    },
    "itemSimQuery": {
      "type": "string",
      "title": "Item Similarity Collection Filter Query",
      "description": "Solr query to filter item similarities (e.g. to filter by similarity type, or algorithm id)",
      "default": "*:*"
    },
    "simItemIdField": {
      "type": "string",
      "title": "Item-Similarity Collection Item Id Field",
      "description": "Solr field name containing stored item ids in the item-similarity collection",
      "default": "item_id_s",
      "hints": ["advanced"]
    },
    "simOtherItemIdField": {
      "type": "string",
      "title": "Item-Similarity Collection Other Item Id Field",
      "description": "Solr field name containing the ids for the *other* item similar to the main item",
      "default": "other_item_id_s",
      "hints": ["advanced"]
    },
    "simSimField": {
      "type": "string",
      "title": "Item-Similarity Collection Similarity Field",
      "description": "Solr field name containing item-item similarity value in the item-similarity collection",
      "default": "sim_d",
      "hints": ["advanced"]
    },
    "numRecsPerUser": {
      "type": "integer",
      "title": "Number of Recommendations / User",
      "description": "Limit on the maximum number of recommendations to compute per user",
      "default": 10
    },
    "type": {
      "type": "string",
      "title": "Spark Job Type",
      "enum": ["item_similarity_recs"],
      "default": "item_similarity_recs",
      "hints": ["readonly"]
    }
  },
  "additionalProperties": true,
  "category": "Other",
  "categoryPriority": 1,
  "unsafe": false,
  "propertyGroups": [{
    "label": "Input/Output Parameters",
    "properties": ["trainingCollection", "trainingDataFilterQuery", "itemSimCollection", "itemSimQuery", "outputRecsCollection"]
  }, {
    "label": "Field Parameters",
    "properties": ["prefUserIdField", "prefItemIdField", "prefWeightField", "simItemIdField", "simOtherItemIdField", "simSimField"]
  }, {
    "label": "Model Tuning Parameters",
    "properties": ["numRecsPerUser"]
  }]
};

export const SchemaParamFields = ({schema}) => {
  const sanitize = str => {
    if (typeof str !== "string") return str;
    return str.replace(/^"(.*)"$/s, "$1").replace(/\\/g, "").replace(/"/g, "'");
  };
  const formatDescription = str => {
    const s = sanitize(str);
    return (/[.!?]\)*$/).test(s) ? s : `${s}.`;
  };
  const {description, properties = {}, required: requiredProps = []} = schema;
  const visibleProps = useMemo(() => Object.entries(properties).filter(([, prop]) => !prop.hints?.includes("hidden")), [properties]);
  return <div>
      {description && <p>{formatDescription(description)}</p>}

      {visibleProps.map(([name, prop]) => {
    const isRequired = requiredProps.includes(name);
    const hasDefault = prop.default !== undefined;
    const rawDefault = prop.default;
    const isComplexDefault = hasDefault && (typeof rawDefault === "object" || typeof rawDefault === "string" && (rawDefault.length > 20 || rawDefault.includes('"')));
    const fieldProps = {
      key: name,
      body: prop.title || name,
      type: prop.type,
      ...prop.title && ({
        post: [<><span className="text-stone-400 dark:text-stone-500">API property: </span>{name}</>]
      }),
      ...isRequired && ({
        required: true
      }),
      ...!isComplexDefault && hasDefault ? {
        default: sanitize(String(rawDefault))
      } : {}
    };
    const isObject = prop.type === "object" && prop.properties;
    const isArrayOfObjects = prop.type === "array" && prop.items?.type === "object" && prop.items.properties;
    return <ParamField {...fieldProps}>
            {prop.description && <p>{formatDescription(prop.description)}</p>}

            {isComplexDefault && <div className="flex">
                <p>
                  <strong>Default:</strong>
                </p>
                <pre className="!my-0">
                  <code>
                    {JSON.stringify(rawDefault, null, 2)}
                  </code>
                </pre>
              </div>}

            {isArrayOfObjects && <div className="flex">
              <p>
                <strong>Object attributes:</strong>
              </p>
              <pre className="!my-0">
                <code>
                  {'{\n'}
                  {Object.entries(prop.items.properties).map(([iname, iprop]) => <>
                      {`  ${iname}`}
                      {prop.items?.required?.includes(iname) && <span style={{
      color: 'red'
    }}> required</span>}
                      {`: {\n    display name: ${sanitize(iprop.title || '')}\n    type: ${iprop.type}\n  }\n`}
                    </>)}
                  {'}'}
                </code>
              </pre>
              </div>}

            {isObject && <Expandable title="properties">
                <SchemaParamFields schema={{
      properties: prop.properties,
      required: prop.required
    }} />
              </Expandable>}
          </ParamField>;
  })}
    </div>;
};

export const LwTemplate = ({title = "Key questions to get you started", icon = "sparkles", cta = "Powered by Agent Studio", linkHref = "https://lucidworks.com/demo/?utm_source=docs&utm_medium=referral&utm_campaign=docs_cta_ai"}) => {
  const [isLoaded, setIsLoaded] = useState(false);
  useEffect(() => {
    const timer = setTimeout(() => {
      setIsLoaded(true);
    }, 500);
    return () => clearTimeout(timer);
  }, []);
  return <div className="lw-template-container">
      <Card title={title} icon={icon}>
        {isLoaded && <span dangerouslySetInnerHTML={{
    __html: `<lw-template id="a029c1a9-28be-427e-b0e1-5d918920246a"></lw-template
            >`
  }} />}
        <Link href={linkHref} className="agent-studio-link text-left text-gray-600 gap-2 dark:text-gray-400 text-sm font-medium flex flex-row items-center hover:text-primary dark:hover:text-primary-light group-hover:text-primary group-hover:dark:text-primary-light">Powered by Lucidworks Agent Studio</Link>
      </Card>
    </div>;
};

[localhost link]: http://localhost:3000/docs/4/fusion-ai/reference/jobs/legacy-item-recommender

[mintlify link]: https://doc.lucidworks.com/docs/4/fusion-ai/reference/jobs/legacy-item-recommender

[old doc.lw link]: https://doc.lucidworks.com/fusion-ai/4.2/562

Compute user recommendations based on a pre-computed item similarity model.

<LwTemplate />

<SchemaParamFields schema={schema} />