@langchain/community
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Third-party integrations for LangChain.js
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{"version":3,"file":"cassandra.cjs","names":["BaseListChatMessageHistory","options: CassandraChatMessageHistoryOptions","storedMessages: StoredMessage[]","message: BaseMessage","CassandraTable"],"sources":["../../../src/stores/message/cassandra.ts"],"sourcesContent":["import { BaseListChatMessageHistory } from \"@langchain/core/chat_history\";\nimport {\n BaseMessage,\n StoredMessage,\n mapChatMessagesToStoredMessages,\n mapStoredMessagesToChatMessages,\n} from \"@langchain/core/messages\";\n\nimport {\n Column,\n CassandraTable,\n CassandraClientArgs,\n} from \"../../utils/cassandra.js\";\n\nexport interface CassandraChatMessageHistoryOptions\n extends CassandraClientArgs {\n keyspace: string;\n table: string;\n sessionId: string;\n}\n\n/**\n * Class for storing chat message history within Cassandra. It extends the\n * BaseListChatMessageHistory class and provides methods to get, add, and\n * clear messages.\n * @example\n * ```typescript\n * const chatHistory = new CassandraChatMessageHistory({\n * cloud: {\n * secureConnectBundle: \"<path to your secure bundle>\",\n * },\n * credentials: {\n * username: \"token\",\n * password: \"<your Cassandra access token>\",\n * },\n * keyspace: \"langchain\",\n * table: \"message_history\",\n * sessionId: \"<some unique session identifier>\",\n * });\n *\n * const chain = new ConversationChain({\n * llm: new ChatOpenAI({ model: \"gpt-4o-mini\" }),\n * memory: chatHistory,\n * });\n *\n * const response = await chain.invoke({\n * input: \"What did I just say my name was?\",\n * });\n * console.log({ response });\n * ```\n */\nexport class CassandraChatMessageHistory extends BaseListChatMessageHistory {\n lc_namespace = [\"langchain\", \"stores\", \"message\", \"cassandra\"];\n\n private cassandraTable: CassandraTable;\n\n private sessionId: string;\n\n private options: CassandraChatMessageHistoryOptions;\n\n private colSessionId: Column;\n\n private colMessageTs: Column;\n\n private colMessageType: Column;\n\n private colData: Column;\n\n constructor(options: CassandraChatMessageHistoryOptions) {\n super();\n this.sessionId = options.sessionId;\n this.options = options;\n\n this.colSessionId = { name: \"session_id\", type: \"text\", partition: true };\n this.colMessageTs = { name: \"message_ts\", type: \"timestamp\" };\n this.colMessageType = { name: \"message_type\", type: \"text\" };\n this.colData = { name: \"data\", type: \"text\" };\n }\n\n /**\n * Method to get all the messages stored in the Cassandra database.\n * @returns Array of stored BaseMessage instances.\n */\n public async getMessages(): Promise<BaseMessage[]> {\n await this.ensureTable();\n\n const resultSet = await this.cassandraTable.select(\n [this.colMessageType, this.colData],\n [{ name: \"session_id\", value: this.sessionId }]\n );\n\n const storedMessages: StoredMessage[] = resultSet.rows.map((row) => ({\n type: row.message_type,\n data: JSON.parse(row.data),\n }));\n\n const baseMessages = mapStoredMessagesToChatMessages(storedMessages);\n return baseMessages;\n }\n\n /**\n * Method to add a new message to the Cassandra database.\n * @param message The BaseMessage instance to add.\n * @returns A promise that resolves when the message has been added.\n */\n public async addMessage(message: BaseMessage): Promise<void> {\n await this.ensureTable();\n const messages = mapChatMessagesToStoredMessages([message]);\n const { type, data } = messages[0];\n\n return this.cassandraTable\n .upsert(\n [[this.sessionId, type, Date.now(), JSON.stringify(data)]],\n [\n this.colSessionId,\n this.colMessageType,\n this.colMessageTs,\n this.colData,\n ]\n )\n .then(() => {});\n }\n\n /**\n * Method to clear all the messages from the Cassandra database.\n * @returns A promise that resolves when all messages have been cleared.\n */\n public async clear(): Promise<void> {\n await this.ensureTable();\n return this.cassandraTable\n .delete({ name: this.colSessionId.name, value: this.sessionId })\n .then(() => {});\n }\n\n /**\n * Method to initialize the Cassandra database.\n * @returns Promise that resolves when the database has been initialized.\n */\n private async ensureTable(): Promise<void> {\n if (this.cassandraTable) {\n return;\n }\n\n const tableConfig = {\n ...this.options,\n primaryKey: [this.colSessionId, this.colMessageTs],\n nonKeyColumns: [this.colMessageType, this.colData],\n };\n\n this.cassandraTable = await new CassandraTable(tableConfig);\n }\n}\n"],"mappings":";;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;AAmDA,IAAa,8BAAb,cAAiDA,yDAA2B;CAC1E,eAAe;EAAC;EAAa;EAAU;EAAW;CAAY;CAE9D,AAAQ;CAER,AAAQ;CAER,AAAQ;CAER,AAAQ;CAER,AAAQ;CAER,AAAQ;CAER,AAAQ;CAER,YAAYC,SAA6C;EACvD,OAAO;EACP,KAAK,YAAY,QAAQ;EACzB,KAAK,UAAU;EAEf,KAAK,eAAe;GAAE,MAAM;GAAc,MAAM;GAAQ,WAAW;EAAM;EACzE,KAAK,eAAe;GAAE,MAAM;GAAc,MAAM;EAAa;EAC7D,KAAK,iBAAiB;GAAE,MAAM;GAAgB,MAAM;EAAQ;EAC5D,KAAK,UAAU;GAAE,MAAM;GAAQ,MAAM;EAAQ;CAC9C;;;;;CAMD,MAAa,cAAsC;EACjD,MAAM,KAAK,aAAa;EAExB,MAAM,YAAY,MAAM,KAAK,eAAe,OAC1C,CAAC,KAAK,gBAAgB,KAAK,OAAQ,GACnC,CAAC;GAAE,MAAM;GAAc,OAAO,KAAK;EAAW,CAAC,EAChD;EAED,MAAMC,iBAAkC,UAAU,KAAK,IAAI,CAAC,SAAS;GACnE,MAAM,IAAI;GACV,MAAM,KAAK,MAAM,IAAI,KAAK;EAC3B,GAAE;EAEH,MAAM,8EAA+C,eAAe;AACpE,SAAO;CACR;;;;;;CAOD,MAAa,WAAWC,SAAqC;EAC3D,MAAM,KAAK,aAAa;EACxB,MAAM,0EAA2C,CAAC,OAAQ,EAAC;EAC3D,MAAM,EAAE,MAAM,MAAM,GAAG,SAAS;AAEhC,SAAO,KAAK,eACT,OACC,CAAC;GAAC,KAAK;GAAW;GAAM,KAAK,KAAK;GAAE,KAAK,UAAU,KAAK;EAAC,CAAC,GAC1D;GACE,KAAK;GACL,KAAK;GACL,KAAK;GACL,KAAK;EACN,EACF,CACA,KAAK,MAAM,CAAE,EAAC;CAClB;;;;;CAMD,MAAa,QAAuB;EAClC,MAAM,KAAK,aAAa;AACxB,SAAO,KAAK,eACT,OAAO;GAAE,MAAM,KAAK,aAAa;GAAM,OAAO,KAAK;EAAW,EAAC,CAC/D,KAAK,MAAM,CAAE,EAAC;CAClB;;;;;CAMD,MAAc,cAA6B;AACzC,MAAI,KAAK,eACP;EAGF,MAAM,cAAc;GAClB,GAAG,KAAK;GACR,YAAY,CAAC,KAAK,cAAc,KAAK,YAAa;GAClD,eAAe,CAAC,KAAK,gBAAgB,KAAK,OAAQ;EACnD;EAED,KAAK,iBAAiB,MAAM,IAAIC,uCAAe;CAChD;AACF"}