dynamodb-utils.js

export const dynamodbUtils = {
  toDynamoDB: function(value) {
    if (typeof (value) === "number") {
      return this.toNumber(value);
    } else if (typeof (value) === "string") {
      return this.toString(value);
    } else if (typeof (value) === "boolean") {
      return this.toBoolean(value);
    } else if (typeof (value) === "object") {
      if (value.length !== undefined) {
        return this.toList(value);
      } else {
        return this.toMap(value);
      }
    } else {
      throw new Error(`Not implemented for ${value}`);
    }
  },

  toString: function(value) {
    if (value === null) { return null; };

    return { S: value };
  },

  toStringSet: function(value) {
    if (value === null) { return null; };

    return { SS: value };
  },

  toNumber: function(value) {
    if (value === null) { return null; };

    return { N: value };
  },

  toNumberSet: function(value) {
    if (value === null) { return null; };

    return { NS: value };
  },

  toBinary: function(value) {
    if (value === null) { return null; };

    return { B: value };
  },

  toBinarySet: function(value) {
    if (value === null) { return null; };

    return { BS: value };
  },

  toBoolean: function(value) {
    if (value === null) { return null; };

    return { BOOL: value };
  },

  toNull: function() {
    return { NULL: null };
  },

  toList: function(values) {
    let out = [];
    for (const value of values) {
      out.push(this.toDynamoDB(value));
    }
    return { L: out }
  },

  toMap: function(mapping) {
    return { M: this.toMapValues(mapping) };
  },

  toMapValues: function(mapping) {
    let out = {};
    for (const [k, v] of Object.entries(mapping)) {
      out[k] = this.toDynamoDB(v);
    }
    return out;
  },

  toS3Object: function(key, bucket, region, version) {
    let payload;
    if (version === undefined) {
      payload = {
        s3: {
          key,
          bucket,
          region,
        }
      };
    } else {
      payload = {
        s3: {
          key,
          bucket,
          region,
          version,
        }
      };
    };
    return this.toString(JSON.stringify(payload));
  },

  fromS3ObjectJson: function(value) {
    throw new Error("not implemented");
  },
}