DB Web Services

    {info} DB Web Services provide methods for storing and searching chemical structures in a persistent database, currently in H2 database. There are methods provided for:

    • creating / deleting tables
    • inserting / deleting / modifying structures and data in the tables
    • executing duplicate, substructure, full fragment and similarity searches

    This documentation describes installation, administration and usage of DB Web Services.

    DB Web Services application is available in two modes:

    1. As part of a microservices system
    2. As standalone web application

    Microservices system mode

    In microservices system mode the DB Web Service runs together with Config service, Discovery service and Gateway service. These three services are mandatory and optionally other services can also be part of the system. All configuration must be done in the Config module.

    The default configuration applies to the microservices system mode.

    The web application runs on host <server-host> and listens on port <gateway-server-port>.

    Standalone web application mode

    In standalone web application mode the DB Web Service runs alone, without the Config service, Discovery service and Gateway service (however the installer installs them, as well).

    The default configuration must be changed according to the standalone web application mode; set

    eureka.client.enabled=false in application.properties file, and

    up to version 22.2.0 spring.cloud.config.failFast=false ,

    spring.cloud.config.enabled=false and

    spring.cloud.config.uri= (so to empty) in bootstrap.properties file

    from version 22.9.0

    set spring.cloud.config.enabled=false and comment out line spring.config.import= in application.properties file.

    All configuration must be done in the DB module.

    The web application runs on host <server-host> and listens on port <server-port>.


    See here.

    Software requirements

    See here


    See here.

    Module is installed into folder: jws/jws-db


    See here.

    Additionally, the IUPAC naming plugin license is required for the usage of name file format.


    Default configuration:

    application.properties description
    spring.config.import=configserver:${CONFIG_SERVER_URI:http\://localhost\:8888}?fail-fast=true&max-attempts=100&max-interval=60000&multiplier=1.2&initial-interval=3000 Added in version 22.6.0.
    eureka.client.enabled=true set eureka.client.enabled=false to switch to standalone DB Web Services application mode
    initOnStart=AUTO initOnStart can be:
    INIT: the existing database is deleted, and a new empty one is created
    AUTO: existing database is started, in case of non-existing database a new empty one is created
    OPEN: existing database is started, in case of non-existing database error is thrown
    OPEN_OR_INIT_ONLY: if OPEN is unsuccessful, then only an INIT step happens, however the service is not run
    updateMode=EXIT updateMode gets in action only if the version number has changed
    updateMode can be
    EXIT: exit if version mode has changed
    DROP: drop old data if version mode has changed
    REINDEX: keep old data and reindex them in order to work with new version
    com.chemaxon.zetor.types[0].version = 1
    com.chemaxon.zetor.types[0].typeName = sample
    com.chemaxon.zetor.types[0].typeId = 1
    com.chemaxon.zetor.types[0].tautomerHandlingMode = OFF
    com.chemaxon.zetor.types[0].standardizerConfig = aromatize

    com.chemaxon.zetor.types[1].version = 1
    com.chemaxon.zetor.types[1].typeName = taumol
    com.chemaxon.zetor.types[1].typeId = 2
    com.chemaxon.zetor.types[1].tautomerHandlingMode = GENERIC
    com.chemaxon.zetor.types[1].standardizerConfig = aromatize
    Here are the molecule types defined.
    You can delete, modify or add new molecules types.
    version must be 1
    typeName must be unique
    typeID must be unique integer tautomerHandlingMode can be OFF or GENERIC or CANONIC_GENERIC_HYBRID (available from version 20.10)
    stereoAssumption can be ABSOLUTE or RELATIVE (available from version 20.12)
    standardizerConfig can be made of action strings
    From version 21.19 the standardizer configuration can be specified also as com.chemaxon.zetor.types[n].standardizerFile but strictly use only one of them, standardizerConfig OR standardizerFile
    Indexing of the types array must always be sequential 0, 1, 2, ...

    All changes take effect only if initOnStart is set to INIT, and the application is re-started. Take care, the existing database will be deleted.

    Performance tuning can be executed by doing some cache related settings. Please use our JChem Engines cache and memory calculator page (take into account that superstructure search is not available) to calculate the appropriate settings.

    All properties calculated by the calculator must be copied into the application.properties file (not into the file specified on the calculator page) like:


    The infix *.runtime* in keys was used in version 19.10 and earlier:

    spring.cloud.config.failFast=true #Removed in version 22.6.0.
    spring.cloud.config.uri=${CONFIG_SERVER_URI:http\://localhost\:8888/} #Removed in version 22.6.0.
    spring.cloud.config.retry.initialInterval=3000 #Removed in version 22.6.0.
    spring.cloud.config.retry.multiplier=1.2 #Removed in version 22.6.0.
    spring.cloud.config.retry.maxInterval=60000 #Removed in version 22.6.0.
    spring.cloud.config.retry.maxAttempts=100 #Removed in version 22.6.0.

    For more settings possibilities see spring documentation page.

    Search logging

    Debug level of search logging can be set in the files configuring the JVM options:

    jws-db-service.vmoptions run-jws-db.vmoptions

    by adding line


    or setting


    in application.properties file.

    High Availability (HA)

    HA and load balancing is provided for DB Web Services, for the only stateful web service in JChem Microservices.

    Running more instances of the db service ensures HA and load balancing.

    In HA mode, Hazelcast is used for distributed caching of the data.

    It can be optionally set that all nodes present in the system have their own cache ('Near' cache). By default, near cache is switched on.

    Features when near cache is switched on:

    • quicker structure search

    • increased memory usage

    • in the case of data update, the system eventually becomes inconsistent; it can take a few seconds to get back again consistent.


    HA mode needs PostgreSQL database installed, user and database created

    Configure HA mode

    HA mode must be configure in /jws-config/common-config/application.properties file

    Example configuration:


    Load balanced example

    Here you find a load balanced example application on GitHub.

    Running the server

    Prerequisites in case of microservices system mode:

    1. Config service is running
    2. Discovery service is running
    3. Gateway service is running

    Run the service in command line in folder jws/jws-db/ :

    jws-db-service --start (on Windows) jws-db-service start (on Linux)


    run-jws-db.exe (on Windows) run-jws-db (on Linux)

    API Documentation

    Find and try out the API on the Swagger UI.

    Mode URL of Swagger UI default URL of Swagger UI
    microservices system <serverhost>:<gateway-port>/jwsdb/API/ localhost:8080/jwsdb/API/
    standalone web application mode <serverhost>:<server-port>/API/ localhost:8062/API/

    Demo site

    For detailed description check out the JWS DB demo site:



    The guidelines, examples on the Demo site or on the Swagger UI API documentation of your installed module display the methods and syntax implemented for reaching the essential chemical searching functionalities of JChem Base.

    Molecule type information

    DB Web Services provides method for getting the available molecule types.

    Every table has a Molecule type: this is a descriptor that is used by the search engine. It contains information about how structures are handled during search. The application has two very simple built in types called: sample (search with aromatization) and taumol (tautomer search). See the type definitions in the application.properties file.

    Store and search molecules and non-chemical data

    Table operations

    Structure Insert/Delete methods

    Duplicate search methods

    Substructure search methods

    Similarity search methods

    {primary} Timeout From version 19.25 the default timeout ( hystrix.command.default.execution.isolation.thread.timeoutInMilliseconds ) is taken into account during indexing. If an indexing job is started already and timeout occurs, then in the background the indexing continues. and the user is informed in the message of the error response about it: "this process has started already will finish in the background" . If the process was only waiting for other indexing processes to finish, then "this process was cancelled" message appears in the error message. The default timeout is 25000 milliseconds. We stop the process slightly before the end of the timeout (default: 300 milliseconds, can be set with zetor.indexing.timeoutDifferenceInMilliseconds property) so we have a chance to provide the answer correctly.

    Data recovery

    The data apparently stored in tables (collections) are stored in the file system under jws-db/data/ folder. The content of that folder must be stored as backup. Furthermore, the application.properties file(s) also should be saved.

    Import/export tables using S3 bucket

    It is possible to use S3 buckets to import / export database tables. For this we use Spring AWS support. Our default settings are different than Spring's defaults so users who are not using this feature can run their services without AWS issues. The current constants are the following:

          auto: false
          static: eu-central-1
          auto: false

    cloud.aws.region.auto is responsible to decide if region should be discovered automatically, or not. If you are running inside AWS infrastructure you want to set this to true. cloud.aws.region.static must be set if can not be determined automatically (the previous setting is responsible for that). Spring's default is us-west-1. cloud.aws.stack.auto is responsible to find AWS stack services automatically by reading standard AWS resources. If you are running your instances on AWS you want to to enable this feature by setting to true.

    Please be aware the following settings are not using Spring Relaxed Binding rules, they must be set exactly like this from properties/yaml file:

    • Use cloud.aws.credentials.useDefaultAwsCredentialsChain=true if you want to use the default AWS chain to discover your credentials. The default chain is searching the following sources in this exact order (and uses the first hit):
    1. reads environment variables
    2. reads JVM system properties
    3. reads profile specific credentials (default profile is called default)
    4. uses EC2 credential provider if available

    If you are using any other method to determine the credentials, this should be switched to false, which is the default value.

    • Use cloud.aws.credentials.accessKey and cloud.aws.credentials.secretKey to manually set a static access key and secret key value.
    • Use cloud.aws.credentials.profilePath to specify your custom profile path URL and use cloud.aws.credentials.profileName to use a different profile from AWS credentials file.

    You can setup S3 import/export the following settings:

    # Specifies whether use FILE based import/export or S3 based import/export. Default is: `FILE`
    # Specifies which S3 bucket to use. Default value: s3://export-bucket/ . The URL should follow the S3 URL scheme, like in the default value.

    AWS Fargate setup

    When running DB Web Services on AWS Fargate, it is recommended to use a persistent data storage (e.g. Amazon RDS) and if upgrading in REINDEX mode, the export/import strategy should be set to S3:

    # Specifies whether use FILE based import/export or S3 based import/export. Default is: FILE
    # Specifies which S3 bucket to use. Default value: s3://export-bucket/ . The URL should follow the S3 URL scheme, like in the default value.

    Because in REINDEX mode the service reimports the tables at startup, the timeout and startPeriod of the AWS Fargate service should be set accordingly so it would give enough time for the reimport. (AWS API Reference - ECS HealthCheck)

    The above import/export settings for S3 should also be set if using /rest-v1/db/additional/{tableName}/importFromFile/{fileName} and /rest-v1/db/additional/{tableName}/exportToFile endpoints on AWS Fargate.

    Setting up backend suitable for AWS Fargate

    DB Web Services use a backend where index data is stored through a JDBC connection. As default this JDBC connection is a file based H2 connection. On AWS Fargate systems persisting data on the file system of the AWS Fargate container is not advised as after deleting the container data gets lost. Therefore we suggest using a database outside the AWS Fargate container.

    An example for setting a PostgreSQL Amazon RDS instance: