Pydantic v2 (#19071)

Co-authored-by: Andrew Morgan <1342360+anoadragon453@users.noreply.github.com>
Co-authored-by: Andrew Morgan <andrew@amorgan.xyz>

Author: V02460

.github/workflows/tests.yml

@@ -207,26 +207,6 @@ jobs:
         env:
           PULL_REQUEST_NUMBER: ${{ github.event.number }}
 
-  lint-pydantic:
-    runs-on: ubuntu-latest
-    needs: changes
-    if: ${{ needs.changes.outputs.linting == 'true' }}
-
-    steps:
-      - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
-        with:
-          ref: ${{ github.event.pull_request.head.sha }}
-      - name: Install Rust
-        uses: dtolnay/rust-toolchain@e97e2d8cc328f1b50210efc529dca0028893a2d9 # master
-        with:
-          toolchain: ${{ env.RUST_VERSION }}
-      - uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # v2.8.1
-      - uses: matrix-org/setup-python-poetry@5bbf6603c5c930615ec8a29f1b5d7d258d905aa4 # v2.0.0
-        with:
-          poetry-version: "2.1.1"
-          extras: "all"
-      - run: poetry run scripts-dev/check_pydantic_models.py
-
   lint-clippy:
     runs-on: ubuntu-latest
     needs: changes
@@ -341,7 +321,6 @@ jobs:
       - lint-mypy
       - lint-crlf
       - lint-newsfile
-      - lint-pydantic
       - check-sampleconfig
       - check-schema-delta
       - check-lockfile
@@ -363,7 +342,6 @@ jobs:
             lint
             lint-mypy
             lint-newsfile
-            lint-pydantic
             lint-clippy
             lint-clippy-nightly
             lint-rust

changelog.d/19071.misc

@@ -0,0 +1 @@
+Update pydantic to v2.

poetry.lock

@@ -220,8 +220,8 @@ netaddr = ">=0.7.18"
 Jinja2 = ">=3.0"
 # 3.2.0 updates collections.abc imports to avoid Python 3.10 incompatibility.
 bleach = ">=3.2.0"
-# We use `assert_never`, which were added in `typing-extensions` 4.1.
-typing-extensions = ">=4.1"
+# pydantic 2.12 depends on typing-extensions>=4.14.1
+typing-extensions = ">=4.14.1"
 # We enforce that we have a `cryptography` version that bundles an `openssl`
 # with the latest security patches.
 cryptography = ">=3.4.7"
@@ -230,9 +230,10 @@ ijson = ">=3.1.4"
 matrix-common = "^1.3.0"
 # We need packaging.verison.Version(...).major added in 20.0.
 packaging = ">=20.0"
-# We support pydantic v1 and pydantic v2 via the pydantic.v1 compat module.
-# See https://github.com/matrix-org/synapse/issues/15858
-pydantic = ">=1.7.4, <3"
+pydantic = [
+    { version = "~=2.8", python = "<3.14" },
+    { version = "~=2.12", python = ">=3.14" },
+]
 
 # This is for building the rust components during "poetry install", which
 # currently ignores the `build-system.requires` directive (c.f.
@@ -335,8 +336,6 @@ all = [
 # can bump versions without having to update the content-hash in the lockfile.
 # This helps prevents merge conflicts when running a batch of dependabot updates.
 ruff = "0.12.10"
-# Type checking only works with the pydantic.v1 compat module from pydantic v2
-pydantic = "^2"
 
 # Typechecking
 lxml-stubs = ">=0.4.0"