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Version: Streamsheets 2.5


Aggregation JSON Aggregation operations process data records and return computed results. Aggregation operations group values from multiple documents together, and can perform a variety of operations on the grouped data to return a single result. Define an aggregation using a JSON cell range.

The Advanced Message Queuing Protocol (AMQP) is an open standard application layer protocol for message-oriented middleware. The defining features of AMQP are message orientation, queuing, routing (including point-to-point and publish and subscribe), reliability and security.

An App contains a set of Streamsheets and provides an outbox. The App executes the Streamsheets, when it runs. The behaviour of an App and the way it processes data streams is defined through its Streamsheets.

Application Properties The application-properties section is a part of the bare message used for structured application data. Intermediaries can use the data within this structure for the purposes of filtering or routing. The keys of this map are restricted to be of type string (which excludes the possibility of a null key) and the values are restricted to be of simple types only, that is, excluding map, list, and array types. Use it to define the Metadata! Click here for a nice overview.

Authentication technology provides access control for systems by checking to see if a user's credentials match the credentials in a database of authorized users or in a data authentication server.

Base Topic The Base Topic of an MQTT Connector sets the highest element in the topic hierarchy. This entry is optional.

Broker refers first of all to the general abstraction concept of a software layer that mediates between heterogeneous application systems and data sources running on different platforms and connected via networks, thus enabling integration into cross-company and cross-organizational applications. In addition, the class of all available software technologies that in any form contribute to the fulfillment of this function is also referred to as broker. Broker can be divided into the different categories according to the underlying paradigm of integration (e.g. Object Request Broker).

Category Labels Specifies if and where the name of the category is given. Its also depends on the the Series Direction.

MongoDB stores documents in collections. Collections are analogous to tables in relational databases. If a collection does not exist, MongoDB creates the collection when you first store data for that collection.

Any command allowed in KSQL table. For further information click here.

Connectors serve the base definition of streams. They contain the information to connect to brokers, servers, clusters and other data spaces. This includes usually addresses and authentication information, such as username and password or certificates.

Consumers are the Stream resource to specify data streams which serve as the input for Streamsheets, thus, they deliver messages to a sheet. You must first choose a Connector and then add the missing information to complete the definition of a data stream.

Data Series Successive data which all belong to one type e.g. names.

Data Point A Data Point is one point out of a whole Data series.

A directory is a location for storing files on your computer. So just write the path to your folder with the required files.

MongoDB stores data records as BSON documents. BSON is a binary representation of JSON documents, though it contains more data types than JSON. Just use the required JSON Range.

Influx InfluxDB is an open-source time series database (TSDB) developed by InfluxData. It is written in Go and optimized for fast, high-availability storage and retrieval of time series data in fields such as operations monitoring, application metrics, Internet of Things sensor data, and real-time analytics. Learn more about it on

Their are a variety of formats used to represent data in a structured and standarized way. JSON is one of them and primarly used in the Streamsheets. It is a text-based data format that is the lightweight alternative to XML widely used on the Web for data interchange. JSON objects are a hierarchy of key-value pairs. This means that any value, e.g. a number or a string, is identified by its key. You could think of the key as the name or the title of its value. In order not to just have a flat list of key-value pairs, these can be ordered and subsumed, e.g. in the Inbox picture the key-value pair “Temperature: 34” is subsumed under the top-element “Data”. See also

Apache Kafka is open source software that enables the storage and processing of data streams over a distributed streaming platform. It provides various interfaces for writing data to Kafka clusters, reading data, importing and exporting data to and from third-party systems.

Line Protocol The InfluxDB line protocol is a text based format for writing points to the database. Points must be in line protocol format for InfluxDB to successfully parse and write points. A single line of text in line protocol format represents one data point in InfluxDB. It informs InfluxDB of the point’s measurement, tag set, field set, and timestamp. Tag set and timestamp are optional. Learn more about it here.

In OPC UA, every entity in the address space is a node. To uniquely identify a Node, each node has a NodeId.

Node Value The Value from the Node you want to write.

The Streamsheet architecture is a loosely coupled Microservice that allows the agile automation of sensors, devices, actuators and applications and its post-processing operations in a spreadsheet manner. This modular architecture allows the parallelization of services and the decomposition of applications into smaller services. Each individual service is independently, continuously deployable and easy to replace without harming the overall service architecture and thus beneficial to scalability.

MongoDB is an open source database that uses a document-oriented data model. Learn more about it on

MQTT (formerly the MQ Telemetry Transport) is a lightweight protocol that’s primarily designed for connecting power-constrained devices over low-bandwidth networks. Though it existed for over a decade, the advent of M2M (machine to machine communications) and Internet of Things made it a popular protocol MQTT (=Message Queuing Telemetry Transport) is a publish and subscribe based messaging protocol. Data is published to a broker. This broker handels all data points in realtime. Every message to the broker is directed to a certain topic. Subscribing to these topics automatically will forward these messages to the subscribers (This is similar to the idea of twitter enabling hashtags to structure information). Topics can be structured in a hierarchy using a “/” to better organise different use cases. (e.g. streamsheets/example/test)

To get the full information go and visit their GitHub Wiki.

Open Platform Communications Unified Architecture (OPC UA) is a machine to machine communication protocol for industrial automation. The transport of data as well as interfaces, security mechanisms and the semantic structure of the data are specified. OPC UA standardizes industrial connectivity and ensures interoperability between products from different manufacturers. Transmitted machine data can be, for example, measured values, sensor data, controlled variables or control instructions.

The payload is part of the transmitted data within the actual message. The payload contains the actual data of the message and is separated from the metadata, that represents the protocol overhead. Payload can be any sensor, actuator devices or application data sent to or received by the Streamsheet via the corresponding topic. In order to integrate the stream data (payload) into your Streamsheet operations the Streamsheet must subscribe to a feeder. The payload content always uses JSON to structure its content.

All data transmitted over the internet is sent and received using a specific set of commands, also known as a protocol. Each protocol is assigned a specific port number. For example, all website data transferred over HTTP uses port 80. Data sent over HTTPS uses port 443.

In computing, the Post Office Protocol (POP) is an application-layer Internet standard protocol used by e-mail clients to retrieve e-mail from a mail server.

Page Size Number of Documents to return per page.

Producers are very similar to Consumers but instead of defining an input data stream, they define an outgoing data stream.

A provider defines the protocol and technology that is used to access a data source. A provider is needed to define a Connector in order to define the access technology needed to communicate with the data source.

Publish and Subscribe
Publish and Subscribe is a event-driven message pattern where publishers are the senders of messages and subscribers are the receivers. Thereby the message is not programmed to be sent to a specific receiver (subscriber). The message is published in a general pattern without knowing the actual receivers. Moreover, all messages published on a topic can be received by all interested subscribers of a topic. Analogously the subscriber filters its messages of interests without the knowledge of the associated publisher. In contrast to message queues which batch messages until they are retrieved, message topics forward messages with no or little queuing, and immediately publish it to all subscribers. Thus, the Streamsheet architecture uses a topic-based filter method. The subscriber receives all messages addressed to the subscribed topic and filters the total number of messages to the relevant subset of messages. The subscription of a topic within a streamsheet can be configured by selecting a feeder subscribing to a topic. On the other the StreamSheet provides functions to publish data.

The Quality of Service (QoS) level is an agreement between the sender of a message and the receiver of a message that defines the guarantee of delivery for a specific message. It depends on the used protocol.
E.g. there are 3 QoS levels in MQTT: At most once (0) At least once (1) Exactly once (2)

Query stands for a specific query to a database. Use a JSON Range in the sheet to define the Query.

Representational State Transfer (REST) is a software architectural style that defines a set of constraints to be used for creating Web services. Web services that conform to the REST architectural style, called RESTful Web services (RWS), provide interoperability between computer systems on the Internet

Every REST Service has a unique adress, the Uniform Resource Locator (URL). This offeres a consistent adressability.

Result Keys You can filter the query results by using specified JSON Keys.

Simple Authentication and Security Layer (SASL) is a framework for authentication and data security in Internet protocols. It decouples authentication mechanisms from application protocols, in theory allowing any authentication mechanism supported by SASL to be used in any application protocol that uses SASL. Application protocols that support SASL typically also support Transport Layer Security (TLS) to complement the services offered by SASL.

Series Direction Specifies whether the data series is horizontal or vertical (rows or columns).

Series Labels Specifies if and where the name of the data series is given. Its also depends on the the Series Direction.

The Simple Mail Transfer Protocol (SMTP) is a communication protocol for electronic mail transmission. User-level email clients typically use SMTP only for sending messages to a mail server for relaying, typically submit outgoing email to the mail server on port 587 or 465.

Sort query result ascending or descending. Use 1 and -1 to sort by creation time, or use a JSON cell range.

Opportunistic TLS (Transport Layer Security) refers to extensions in plain text communication protocols, which offer a way to upgrade a plain text connection to an encrypted (TLS or SSL) connection instead of using a separate port for encrypted communication. Several protocols use a command named "STARTTLS" for this purpose. It is primarily intended as a countermeasure to passive monitoring.

Status Code REST APIs use the Status-Line part of an HTTP response message to inform clients of their request’s overarching result. HTTP defines forty standard status codes that can be used to convey the results of a client’s request. E.g. Code: 200 = "OK"

A Streamsheet is a spreadsheet extended by capabilities to easily allow real-time data stream processing. It allows to automate and dynamically calculate sensor, actuator, device and application data within a data stream architecture. The streamsheet subscribes a specific data source, receives event data, analyses, processes or forwards this data by publishing new stream data or messages on the same or different data source. Multiple streamsheets within one app can be used to execute a sequential or parallel order of stream processes continuously and in real-time. A streamsheet can be compared to a microservice within a stream based architecture.

The time to wait for an answer.

Transport Layer Security (TLS), and its now-deprecated predecessor, Secure Sockets Layer (SSL), are cryptographic protocols designed to provide communications security over a computer network.

Uniform Resource Locator (URL) identifies and localizes a resource within a network. URLs are a sub group of the Uniform Resource Identifiers (URI) and are the most common.

User Properties User properties on MQTT.PUBLISH are forwarded with the message and are defined by the client applications. They are forwarded by the server to the receiver of the message. Use it to define the Metadata!