PeerDB

PeerDB a database software layer which supports different types of collaboration out of the box. Build collaborative applications like you would build traditional applications and leave it to PeerDB to take care of collaboration. Common user interface components are included.

Demos:

• wikipedia.peerdb.org: a search service for English Wikipedia articles, Wikimedia Commons files, and Wikidata data.
• moma.peerdb.org: a search service for The Museum of Modern Art (MoMA) artists and artworks.
• omni.peerdb.org: combination of other demos into one search service.

Components

• PeerDB Store is a key-value store with features enabling collaboration. It supports versioning, forking and merging, transactions at human-scale (i.e., to support merge requests), concurrent different views over the data.
• PeerDB Coordinator provides an append-only log of operations to support synchronizing real-time collaboration sessions.
• PeerDB Storage provides file storage with versioning and interactive uploads.
• PeerDB Search is a search for semantic, structured, and full-text data. It is opinionated open source search system incorporating best practices in search and user interfaces/experience to provide an intuitive, fast, and easy to use search over semantic, structured, and full-text data. Its user interface automatically adapts to data and search results and provides relevant filters. The goal of the user interface is to allow users without technical knowledge to easily find results they want, without having to write queries.

Installation

You can run PeerDB behind a reverse proxy (which should support HTTP2), or simply run it directly (it is safe to do so). PeerDB is compiled into one backend binary which has frontend files embedded and they are served by the backend as well.

The releases page contains a list of stable versions. Each includes:

• A statically compiled binary.
• Docker images.

Static binary

The latest stable statically compiled binary for Linux (amd64) is available at:

https://gitlab.com/peerdb/peerdb/-/releases/permalink/latest/downloads/linux-amd64/peerdb

You can also download older versions on the releases page.

The latest successfully built development (main branch) binary is available at:

https://gitlab.com/peerdb/peerdb/-/jobs/artifacts/main/raw/peerdb-linux-amd64?job=docker

Docker

Docker images for stable versions are available as:

registry.gitlab.com/peerdb/peerdb/tag/<version>:latest

<version> is a version string with . replaced with -. E.g., v0.1.0 becomes v0-1-0.

The docker image contains only PeerDB binary, which is image's entrypoint. If you need a shell as well, then use the debug version of the image:

registry.gitlab.com/peerdb/peerdb/tag/<version>:latest-debug

In that case you have to override the entrypoint (i.e., --entrypoint sh argument to docker run).

The latest successfully built development (main branch) image is available as:

registry.gitlab.com/peerdb/peerdb/branch/main:latest

generated in the current directory as described above:

Usage

PeerDB requires an ElasticSearch instance. To run one locally you can use Docker:

docker network create peerdb
docker run -d --network peerdb --name elasticsearch -p 127.0.0.1:9200:9200 \
 -e network.bind_host=0.0.0.0 -e network.publish_host=elasticsearch -e ES_JAVA_OPTS="-Xmx1000m" \
 -e "discovery.type=single-node" -e "xpack.security.enabled=false" -e "ingest.geoip.downloader.enabled=false" \
 elasticsearch:7.16.3

Feel free to change any of the above parameters (e.g., remove ES_JAVA_OPTS if you have enough memory). The parameters above are primarily meant for development on a local machine.

ElasticSearch instance needs to have an index with documents in PeerDB schema and configured with PeerDB mapping. If you already have such an index, proceed to run PeerDB, otherwise first populate ElasticSearch with data.

Next, to run PeerDB you need a HTTPS TLS certificate (as required by HTTP2). When running locally you can use mkcert, a tool to create a local CA keypair which is then used to create a TLS certificate. Use Go 1.23 or newer.

go install filippo.io/mkcert@latest
mkcert -install
mkcert localhost 127.0.0.1 ::1

This creates two files, localhost+2.pem and localhost+2-key.pem, which you can provide to PeerDB as:

./peerdb -k localhost+2.pem -K localhost+2-key.pem

When running using Docker, you have to provide them to the container through a volume, e.g.:

docker run -d --network peerdb --name peerdb -p 8080:8080 -v "$(pwd):/data" \
 registry.gitlab.com/peerdb/peerdb/branch/main:latest -e http://elasticsearch:9200 \
 -k /data/localhost+2.pem -K /data/localhost+2-key.pem

Open https://localhost:8080/ in your browser to access the web interface.

Temporary accepted self-signed certificates are not recommended because not all browser features work. If you want to use a self-signed certificate instead of mkcert, add the certificate to your browser's certificate store.

When running it directly publicly on the Internet (it is safe to do so), PeerDB is able to obtain a HTTPS TLS certificate from Let's Encrypt automatically:

docker run -d --network peerdb --name peerdb -p 443:8080 -v "$(pwd):/data" \
 registry.gitlab.com/peerdb/peerdb/branch/main:latest -e http://elasticsearch:9200 \
 --domain public.domain.example.com -E name@example.com -C /data/letsencrypt

PeerDB would then be available at https://public.domain.example.com.

When using Let's Encrypt you accept its Terms of Service.

Populating with data

Power of PeerDB Search comes from having data in ElasticSearch index organized into documents in PeerDB schema. The schema is designed to allow describing almost any data. Moreover, data and properties to describe data can be changed at runtime without having to reconfigure PeerDB Search, e.g., it adapts filters automatically. The schema also allows multiple data sources to be used and merged together.

PeerDB schema of documents is fully described in JSON Schema and is available here. But at a high-level look like:

{
  "id": "22 character ID",
  "score": 0.5,
  "claims": {
    "id": [
      {
        "id": "22 character ID",
        "confidence": 1.0,
        "prop": {
          "id": "22 character property ID"
        },
        "id": "external ID value"
      }
    ],
    "ref": [...],
    "text": [...],
    "amount": [...],
    "rel": [...],
    "file": [...],
    "time": [...]
  }
}

Besides core metadata (id and score) all other data is organized in claims (seen under claims claims above) which are then organized based on claim (data) type. For example, there are id claims which are used to store external ID values. prop is a reference to a property document which describes the ID value.

Which properties you use and how you use them to map your data to PeerDB documents is left to you. We do suggest that you first populate the index using core PeerDB properties. You can do that by running:

./peerdb populate

This also creates an ElasticSearch index if it does not yet exist and configures it with PeerDB Search mapping. Otherwise you have to create such index yourself.

Then you populate the index with documents for properties for you data. For example, if you have a blog post like:

{
  "id": 123,
  "title": "Some title",
  "body": "Some <b>blog post</b> body HTML",
  "author": {
    "username": "foobar",
    "displayName": "Foo Bar"
  }
}

To convert the blog post:

• You could create two documents, one for title property and another for body property. But you could also decide to map title to existing NAME core property, and body to existing DESCRIPTION (for shorter HTML contents shown in search results as well) or ARTICLE (for longer HTML contents) core property (and its label HAS_ARTICLE).
• Maybe you also want to record the original blog post ID and author username, so create property documents for them as well.
• Author's displayName can be mapped to NAME core property.
• Another property document is needed for the author property.
• Documents should also have additional claims to describe relations between them. Properties should be marked as properties and which claim type they are meant to be used for. It is useful to create properties for user documents and blog post documents, which can in turn be more general (core) items.

Assuming that the author does not yet have its document, you could convert the above blog post into the following two PeerDB documents:

{
  "id": "LcrxeiU9XjxosmX8kiPCx6",
  "score": 0.5,
  "claims": {
    "text": [
      {
        "id": "YWYAgufBtjegbQc512GFci",
        "confidence": 1.0,
        "prop": {
          "id": "CjZig63YSyvb2KdyCL3XTg" // NAME
        },
        "html": {
          "en": "Foo Bar"
        }
      }
    ],
    "id": [
      {
        "id": "9TfczNe5aa4LrKqWQWfnFF",
        "confidence": 1.0,
        "prop": {
          "id": "Hx5zknvxsmPRiLFbGMPeiZ" // author username
        },
        "id": "foobar"
      }
    ],
    "rel": [
      {
        "id": "sgpzxwxPyn51j5VfH992ZQ",
        "confidence": 1.0,
        "prop": {
          "id": "CAfaL1ZZs6L4uyFdrJZ2wN" // TYPE
        },
        "to": {
          "id": "6asppjBfRGSTt5Df7Zvomb" // user
        }
      }
    ]
  }
}

{
  "id": "MpGZyd7grTBPYhMhETAuHV",
  "score": 0.5,
  "claims": {
    "text": [
      {
        "id": "KjwGqHqihAQEgNabdNQSNc",
        "confidence": 1.0,
        "prop": {
          "id": "CjZig63YSyvb2KdyCL3XTg" // NAME
        },
        "html": {
          "en": "Some title"
        }
      },
      {
        "id": "VdX1HZm1ETw8K77nLTV6yt",
        "confidence": 1.0,
        "prop": {
          "id": "FJJLydayUgDuqFsRK2ZtbR" // ARTICLE
        },
        "html": {
          "en": "Some <b>blog post</b> body HTML"
        }
      }
    ],
    "id": [
      {
        "id": "Ci3A1tLF6MHZ4y5zBibvGg",
        "confidence": 1.0,
        "prop": {
          "id": "8mu7vrUK7zJ4Me2JwYUG6t" // blog post ID
        },
        "id": "123"
      }
    ],
    "rel": [
      {
        "id": "xbufQEChDXvtg3hh4i1PvT",
        "confidence": 1.0,
        "prop": {
          "id": "fmUeT7JN8qPuFw28Vdredm" // author
        },
        "to": {
          "id": "LcrxeiU9XjxosmX8kiPCx6" // Foo Bar
        }
      },
      {
        "id": "LJNg7QaiMxE1crjMiijpaN",
        "confidence": 1.0,
        "prop": {
          "id": "CAfaL1ZZs6L4uyFdrJZ2wN" // TYPE
        },
        "to": {
          "id": "3APZXnK3uofpdEJV55Po18" // blog post
        }
      },
      {
        "id": "UxhYEJY6mpA147eujZ489B",
        "confidence": 1.0,
        "prop": {
          "id": "5SoFeEFk5aWXUYFC1EZFec" // LABEL
        },
        "to": {
          "id": "MQYs7JmAR3tge25eTPS8XT" // HAS_ARTICLE
        }
      }
    ]
  }
}

Some additional documents need to exist in the index as well. Click to expand to see them.

{
  "id": "Hx5zknvxsmPRiLFbGMPeiZ",
  "score": 0.5,
  "claims": {
    "text": [
      {
        "id": "c4xGoqaYKaFNqy6hD7RgV8",
        "confidence": 1.0,
        "prop": {
          "id": "CjZig63YSyvb2KdyCL3XTg" // NAME
        },
        "html": {
          "en": "author username"
        }
      }
    ],
    "rel": [
      {
        "id": "5zZZ6nJFKuA5oNBu9QbsYY",
        "confidence": 1.0,
        "prop": {
          "id": "CAfaL1ZZs6L4uyFdrJZ2wN" // TYPE
        },
        "to": {
          "id": "HohteEmv2o7gPRnJ5wukVe" // PROPERTY
        }
      },
      {
        "id": "jjcWxq9VoVLhKqV2tnqz1A",
        "confidence": 1.0,
        "prop": {
          "id": "CAfaL1ZZs6L4uyFdrJZ2wN" // TYPE
        },
        "to": {
          "id": "UJEVrqCGa9f3vAWi2mNWc7" // IDENTIFIER_CLAIM_TYPE
        }
      }
    ]
  }
}

{
  "id": "8mu7vrUK7zJ4Me2JwYUG6t",
  "score": 0.5,
  "claims": {
    "text": [
      {
        "id": "Bj3wKeu49j8ncXYpZ7tuZ5",
        "confidence": 1.0,
        "prop": {
          "id": "CjZig63YSyvb2KdyCL3XTg" // NAME
        },
        "html": {
          "en": "blog post ID"
        }
      }
    ],
    "rel": [
      {
        "id": "DWYDFZ2DbasS4Tyehnko2U",
        "confidence": 1.0,
        "prop": {
          "id": "CAfaL1ZZs6L4uyFdrJZ2wN" // TYPE
        },
        "to": {
          "id": "HohteEmv2o7gPRnJ5wukVe" // PROPERTY
        }
      },
      {
        "id": "ivhonZLA2ktDwyMawBLuKV",
        "confidence": 1.0,
        "prop": {
          "id": "CAfaL1ZZs6L4uyFdrJZ2wN" // TYPE
        },
        "to": {
          "id": "UJEVrqCGa9f3vAWi2mNWc7" // IDENTIFIER_CLAIM_TYPE
        }
      }
    ]
  }
}

{
  "id": "fmUeT7JN8qPuFw28Vdredm",
  "score": 0.5,
  "claims": {
    "text": [
      {
        "id": "1NH97QxtHqJS6JAz1hzCxo",
        "confidence": 1.0,
        "prop": {
          "id": "CjZig63YSyvb2KdyCL3XTg" // NAME
        },
        "html": {
          "en": "author"
        }
      }
    ],
    "rel": [
      {
        "id": "gK8nXxJ3AXErTmGPoAVF78",
        "confidence": 1.0,
        "prop": {
          "id": "CAfaL1ZZs6L4uyFdrJZ2wN" // TYPE
        },
        "to": {
          "id": "HohteEmv2o7gPRnJ5wukVe" // PROPERTY
        }
      },
      {
        "id": "pDBnb32Vd2VPd2UjPnd1eS",
        "confidence": 1.0,
        "prop": {
          "id": "CAfaL1ZZs6L4uyFdrJZ2wN" // TYPE
        },
        "to": {
          "id": "HZ41G8fECg4CjfZN4dmYwf" // RELATION_CLAIM_TYPE
        }
      }
    ]
  }
}

{
  "id": "6asppjBfRGSTt5Df7Zvomb",
  "score": 0.5,
  "claims": {
    "text": [
      {
        "id": "cVvsHG2ru2ojRJhV27Zj3E",
        "confidence": 1.0,
        "prop": {
          "id": "CjZig63YSyvb2KdyCL3XTg" // NAME
        },
        "html": {
          "en": "user"
        }
      }
    ],
    "rel": [
      {
        "id": "79m7fNMHy7SRinSmB3WARM",
        "confidence": 1.0,
        "prop": {
          "id": "CAfaL1ZZs6L4uyFdrJZ2wN" // TYPE
        },
        "to": {
          "id": "HohteEmv2o7gPRnJ5wukVe" // PROPERTY
        }
      },
      {
        "id": "EuGC7ZRK7weuHNoZLDC8ah",
        "confidence": 1.0,
        "prop": {
          "id": "CAfaL1ZZs6L4uyFdrJZ2wN" // TYPE
        },
        "to": {
          "id": "6HpkLLj1iSK3XBhgHpc6n3" // ITEM
        }
      }
    ]
  }
}

{
  "id": "3APZXnK3uofpdEJV55Po18",
  "score": 0.5,
  "claims": {
    "text": [
      {
        "id": "961QCaiVomNHjjwRKtNejK",
        "confidence": 1.0,
        "prop": {
          "id": "CjZig63YSyvb2KdyCL3XTg" // NAME
        },
        "html": {
          "en": "blog post"
        }
      }
    ],
    "rel": [
      {
        "id": "c24VwrPEMwZUhRgECzSn1b",
        "confidence": 1.0,
        "prop": {
          "id": "CAfaL1ZZs6L4uyFdrJZ2wN" // TYPE
        },
        "to": {
          "id": "HohteEmv2o7gPRnJ5wukVe" // PROPERTY
        }
      },
      {
        "id": "faByPL18Y1ZH2NAhea4FBy",
        "confidence": 1.0,
        "prop": {
          "id": "CAfaL1ZZs6L4uyFdrJZ2wN" // TYPE
        },
        "to": {
          "id": "6HpkLLj1iSK3XBhgHpc6n3" // ITEM
        }
      }
    ]
  }
}

MoMA search

To populate search with The Museum of Modern Art (MoMA) artists and artworks (from this dataset), clone the repository and run (you need Go 1.23 or newer):

make moma
./moma

Runtime is few minutes. If you also want to add articles (to have more full-text data) and (more) images from MoMA's website, run instead:

./moma --website-data

Fetching data from the website takes time, so runtime is around 12 hours.

Wikipedia search

To populate search with English Wikipedia articles, Wikimedia Commons files, and Wikidata data, clone the repository and run (you need Go 1.23 or newer):

make wikipedia
./wikipedia

This will do multiple passes:

• wikidata downloads Wikidata dump and imports data into search (70 GB download, runtime 2 days).
• commons-files populates search with Wikimedia Commons files from images table SQL dump (10 GB download, runtime 1 day).
• wikipedia-files populates search with Wikipedia files from table SQL dump (100 MB download, runtime 10 minutes).
• commons (20 GB download, runtime 3 days)
• wikipedia-articles downloads Wikipedia articles HTML dump and imports articles (100 GB download, runtime 0.5 days)
• wikipedia-file-descriptions downloads Wikipedia files HTML dump and imports file descriptions (2 GB download, runtime 1 hour)
• wikipedia-categories downloads Wikipedia categories HTML dump and imports their articles as descriptions (2 GB download, runtime 1 hour)
• wikipedia-templates uses API to fetch data about templates Wikipedia (runtime 0.5 days)
• commons-file-descriptions uses API to fetch descriptions of Wikimedia Commons files (runtime 35 days)
• commons-categories uses API to fetch data about categories Wikimedia Commons (runtime 4 days)
• commons-templates uses API to fetch data about templates Wikimedia Commons (runtime 2.5 hours)
• prepare goes over imported documents and process them for PeerDB Search (runtime 6 days).
• optimize forces merging of ElasticSearch segments (runtime few hours).

The whole process requires substantial amount of disk space (at least 1.5 TB), bandwidth, and time (weeks). Because of this you might want to run only a subset of passes.

To populate only with Wikidata (all references to Wikimedia Commons files will not be available):

./wikipedia wikidata
./wikipedia prepare

To populate with Wikidata and with basic metadata of Wikimedia Commons files:

./wikipedia wikidata
./wikipedia commons-files
./wikipedia prepare

Or maybe you also want English Wikipedia articles:

./wikipedia wikidata
./wikipedia commons-files
./wikipedia wikipedia-articles
./wikipedia prepare

Configuration

PeerDB can be configured through CLI arguments and a config file. CLI arguments have precedence over the config file. Config file is a YAML file with the structure corresponding to the structure of CLI flags and commands. Run ./peerdb --help for list of available flags and commands. If no command is specified, serve command is the default.

Each PeerDB instance can serve multiple sites and Let's Encrypt can be used to obtain HTTPS TLS certificates for them automatically. Example config file for all demos is available in demos.yml. It configures sites, their titles, and ElasticSearch indices for each site. To use the config file with Docker, you could do:

docker run -d --network peerdb --name peerdb -p 443:8080 -v "$(pwd):/data" \
 registry.gitlab.com/peerdb/peerdb/branch/main:latest -e http://elasticsearch:9200 \
 -E name@example.com -C /data/letsencrypt -c /data/demos.yml

Size of documents filter

PeerDB Search can filter on size of documents, but it requires installed mapper-size ElasticSearch plugin and enabled size field in the index. If you use populate command to create the index, you can enable the size field with the --size-field argument:

./peerdb --size-field populate

Alternatively, you can set sizeField in site configuration.

If you use Docker to run ElasticSearch, you can use create a custom Docker image with the plugin installed, or run on your running container:

docker exec -t -i elasticsearch bin/elasticsearch-plugin install mapper-size
docker restart elasticsearch

Use with ElasticSearch alias

If you use an ElasticSearch alias instead of an index, PeerDB Search will provide a filter to filter documents based on which index they come from.

Development

During PeerDB development run backend and frontend as separate processes. During development the backend proxies frontend requests to Vite, which in turn compiles frontend files and serves them, hot-reloading the frontend as necessary.

Backend

The backend is implemented in Go (requires 1.23 or newer) and provides a HTTP2 API. Node 20 or newer is required as well.

Then clone the repository and run:

make peerdb
./peerdb -D -k localhost+2.pem -K localhost+2-key.pem

localhost+2.pem and localhost+2-key.pem are files of a TLS certificate generated as described in the Usage section. Backend listens at https://localhost:8080/.

-D CLI argument makes the backend proxy unknown requests (non-API requests) to the frontend. In this mode any placeholders in HTML files are not rendered.

You can also run make watch to reload the backend on file changes. You have to install CompileDaemon first:

go install github.com/githubnemo/CompileDaemon@latest

Frontend

The frontend is implemented in TypeScript and Vue and during development we use Vite. Vite compiles frontend files and serves them. It also watches for changes in frontend files, recompiles them, and hot-reloads the frontend as necessary. Node 20 or newer is required.

To install all dependencies and run frontend for development:

npm install
npm run serve

Open https://localhost:8080/ in your browser, which will connect you to the backend which then proxies unknown requests (non-API requests) to the frontend.

GitHub mirror

There is also a read-only GitHub mirror available, if you need to fork the project there.

Acknowledgements

This project was funded through the NGI0 Discovery Fund, a fund established by NLnet with financial support from the European Commission's Next Generation Internet programme, under the aegis of DG Communications Networks, Content and Technology under grant agreement No 825322.

The project gratefully acknowledge the HPC RIVR consortium and EuroHPC JU for funding this project by providing computing resources of the HPC system Vega at the Institute of Information Science.

Funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or European Commission. Neither the European Union nor the granting authority can be held responsible for them. Funded within the framework of the NGI Search project under grant agreement No 101069364.