Separate release notes by year to reduce page length (#1171)

* Break release notes into years to reduce page length

* Missed edit in the previous commit

* Remove hidden "old release notes" page

content/develop/quick-references/_index.md

@@ -15,9 +15,9 @@ A dense list of Streamlit commands with example syntax.
 
 </RefCard>
 
-<RefCard href="/develop/quick-reference/changelog">
+<RefCard href="/develop/quick-reference/release-notes">
 
-<h5>Changelog</h5>
+<h5>Release notes</h5>
 
 See how Streamlit has changed with each new version.
 

content/develop/quick-references/release-notes/2019.md

@@ -0,0 +1,294 @@
+---
+title: 2019 release notes
+slug: /develop/quick-reference/release-notes/2019
+description: A changelog of highlights and fixes for each version of Streamlit.
+keywords: changelog, release notes, version history
+---
+
+# 2019 release notes
+
+This page contains release notes for Streamlit versions released in 2019. For the latest version of Streamlit, see [Release notes](/develop/quick-reference/release-notes).
+
+## Version 0.52.0
+
+_Release date: December 20, 2019_
+
+**Highlights:**
+
+- 📤 Preview release of the file uploader widget. To try it out just call
+  [`st.file_uploader`](https://docs.streamlit.io/en/latest/api.html#streamlit.file_uploader)!
+
+  _Note that as a **preview release** things may change in the near future.
+  Looking forward to hearing input from the community before we stabilize the
+  API!_
+
+- 👋 Support for [emoji codes](https://www.webfx.com/tools/emoji-cheat-sheet/) in
+  `st.write` and `st.markdown`! Try it out with `st.write("Hello :wave:")`.
+
+**Breaking changes:**
+
+- 🧹 `st.pyplot` now clears figures by default, since that's what you want 99% of
+  the time. This allows you to create two or more Matplotlib charts without
+  having to call
+  [`pyplot.clf`](https://matplotlib.org/3.1.1/api/_as_gen/matplotlib.pyplot.clf.html)
+  every time. If you want to turn this behavior off, use
+  [`st.pyplot(clear_figure=False)`](https://docs.streamlit.io/en/latest/api.html#streamlit.pyplot)
+- 📣 `st.cache` no longer checks for input mutations. This is the first change
+  of our ongoing effort to simplify the caching system and prepare Streamlit
+  for the launch of other caching primitives like Session State!
+
+## Version 0.51.0
+
+_Release date: November 30, 2019_
+
+**Highlights:**
+
+- 🐕 You can now tweak the behavior of the file watcher with the config option `server.fileWatcherType`. Use it to switch between:
+  - `auto` (default) : Streamlit will attempt to use the watchdog module, and
+    falls back to polling if watchdog is not available.
+  - `watchdog` : Force Streamlit to use the watchdog module.
+  - `poll` : Force Streamlit to always use polling.
+  - `none` : Streamlit will not watch files.
+
+**Notable bug fixes:**
+
+- Fix the "keyPrefix" option in static report sharing [#724](https://github.com/streamlit/streamlit/pull/724)
+- Add support for getColorX and getTargetColorX to DeckGL Chart [#718](https://github.com/streamlit/streamlit/pull/718)
+- Fixing Tornado on Windows + Python 3.8 [#682](https://github.com/streamlit/streamlit/pull/682)
+- Fall back on webbrowser if xdg-open is not installed on Linux [#701](https://github.com/streamlit/streamlit/pull/701)
+- Fixing number input spin buttons for Firefox [#683](https://github.com/streamlit/streamlit/pull/683)
+- Fixing CTRL+ENTER on Windows [#699](https://github.com/streamlit/streamlit/pull/699)
+- Do not automatically create credential file when in headless mode [#467](https://github.com/streamlit/streamlit/pull/467)
+
+## Version 0.50.1
+
+_Release date: November 10, 2019_
+
+**Highlights:**
+
+- 👩‍🎓 SymPy support and ability to draw mathematical expressions using LaTeX! See
+  [`st.latex`](/develop/api-reference/text/st.latex),
+  [`st.markdown`](/develop/api-reference/text/st.markdown),
+  and
+  [`st.write`](/develop/api-reference/write-magic/st.write).
+- 🌄 You can now set config options using environment variables. For example,
+  `export STREAMLIT_SERVER_PORT=9876`.
+- 🐱 Ability to call `streamlit run` directly with Github and Gist URLs. No
+  need to grab the "raw" URL first!
+- 📃 Cleaner exception stack traces. We now remove all Streamlit-specific code
+  from stack traces originating from the user's app.
+
+## Version 0.49.0
+
+_Release date: October 23, 2019_
+
+**Highlights:**
+
+- 💯 New input widget for entering numbers with the keyboard: `st.number_input()`
+- 📺 Audio/video improvements: ability to load from a URL, to embed YouTube
+  videos, and to set the start position.
+- 🤝 You can now (once again) share static snapshots of your apps to S3! See
+  the S3 section of `streamlit config show` to set it up. Then share from
+  top-right menu.
+- ⚙️ Use `server.baseUrlPath` config option to set Streamlit's URL to something
+  like `http://domain.com/customPath`.
+
+**Notable bug fixes:**
+
+- Fixes numerous Windows bugs, including [Issues
+  #339](https://github.com/streamlit/streamlit/issues/399) and
+  [#401](https://github.com/streamlit/streamlit/issues/301).
+
+## Version 0.48.0
+
+_Release date: October 12, 2019_
+
+**Highlights:**
+
+- 🔧 Ability to set config options as command line flags or in a local config file.
+- ↕️ You can now maximize charts and images!
+- ⚡ Streamlit is now much faster when writing data in quick succession to your app.
+- ✳️ Ability to blacklist folder globs from "run on save" and `@st.cache` hashing.
+- 🎛️ Improved handling of widget state when Python file is modified.
+- 🙈 Improved HTML support in `st.write` and `st.markdown`. HTML is still unsafe, though!
+
+**Notable bug fixes:**
+
+- Fixes `@st.cache` bug related to having your Python environment on current
+  working directory. [Issue #242](https://github.com/streamlit/streamlit/issues/242)
+- Fixes loading of root url `/` on Windows. [Issue #244](https://github.com/streamlit/streamlit/issues/244)
+
+## Version 0.47.0
+
+_Release date: October 1, 2019_
+
+**Highlights:**
+
+- 🌄 New hello.py showing off 4 glorious Streamlit apps. Try it out!
+- 🔄 Streamlit now automatically selects an unused port when 8501 is already in use.
+- 🎁 Sidebar support is now out of beta! Just start any command with `st.sidebar.` instead of `st.`
+- ⚡ Performance improvements: we added a cache to our websocket layer so we no longer re-send data to the browser when it hasn't changed between runs
+- 📈 Our "native" charts `st.line_chart`, `st.area_chart` and `st.bar_chart` now use Altair behind the scenes
+- 🔫 Improved widgets: custom st.slider labels; default values in multiselect
+- 🕵️‍♀️ The filesystem watcher now ignores hidden folders and virtual environments
+- 💅 Plus lots of polish around caching and widget state management
+
+**Breaking change:**
+
+- 🛡️ We have temporarily disabled support for sharing static "snapshots" of Streamlit apps. Now that we're no longer in a limited-access beta, we need to make sure sharing is well thought through and abides by laws like the DMCA. But we're working on a solution!
+
+## Version 0.46.0
+
+_Release date: September 19, 2019_
+
+**Highlights:**
+
+- ✨ Magic commands! Use `st.write` without typing `st.write`. See
+  [https://docs.streamlit.io/en/latest/api.html#magic-commands](https://docs.streamlit.io/en/latest/api.html#magic-commands)
+- 🎛️ New `st.multiselect` widget.
+- 🐍 Fixed numerous install issues so now you can use `pip install streamlit`
+  even in Conda! We've therefore deactivated our Conda repo.
+- 🐞 Multiple bug fixes and additional polish in preparation for our launch!
+
+**Breaking change:**
+
+- 🛡️ HTML tags are now blacklisted in `st.write`/`st.markdown` by default. More
+  information and a temporary work-around at:
+  [https://github.com/streamlit/streamlit/issues/152](https://github.com/streamlit/streamlit/issues/152)
+
+## Version 0.45.0
+
+_Release date: August 28, 2019_
+
+**Highlights:**
+
+- 😱 Experimental support for _sidebar_! Let us know if you want to be a beta
+  tester.
+- 🎁 Completely redesigned `st.cache`! Much more performant, has a cleaner API,
+  support for caching functions called by `@st.cached` functions,
+  user-friendly error messages, and much more!
+- 🖼️ Lightning fast `st.image`, ability to choose between JPEG and PNG
+  compression, and between RGB and BGR (for OpenCV).
+- 💡 Smarter API for `st.slider`, `st.selectbox`, and `st.radio`.
+- 🤖 Automatically fixes the Matplotlib backend -- no need to edit .matplotlibrc
+
+## Version 0.44.0
+
+_Release date: July 28, 2019_
+
+**Highlights:**
+
+- ⚡ Lightning-fast reconnect when you do a ctrl-c/rerun on your Streamlit code
+- 📣 Useful error messages when the connection fails
+- 💎 Fixed multiple bugs and improved polish of our newly-released interactive widgets
+
+## Version 0.43.0
+
+_Release date: July 9, 2019_
+
+**Highlights:**
+
+- ⚡ Support for interactive widgets! 🎈🎉
+
+## Version 0.42.0
+
+_Release date: July 1, 2019_
+
+**Highlights:**
+
+- 💾 Ability to save Vega-Lite and Altair charts to SVG or PNG
+- 🐇 We now cache JS files in your browser for faster loading
+- ⛔ Improvements to error-handling inside Streamlit apps
+
+## Version 0.41.0
+
+_Release date: June 24, 2019_
+
+**Highlights:**
+
+- 📈 Greatly improved our support for named datasets in Vega-Lite and Altair
+- 🙄 Added ability to ignore certain folders when watching for file changes. See the `server.folderWatchBlacklist` config option.
+- ☔ More robust against syntax errors on the user's script and imported modules
+
+## Version 0.40.0
+
+_Release date: June 10, 2019_
+
+**Highlights:**
+
+- Streamlit is more than 10x faster. Just save and watch your analyses update instantly.
+- We changed how you run Streamlit apps:
+  `$ streamlit run your_script.py [script args]`
+- Unlike the previous versions of Streamlit, `streamlit run [script] [script args]` creates a server (now you don't need to worry if the proxy is up). To kill the server, all you need to do is hit **Ctrl+c**.
+
+**Why is this so much faster?**
+
+Now, Streamlit keeps a single Python session running until you kill the server. This means that Streamlit can re-run your code without kicking off a new process; imported libraries are cached to memory. An added bonus is that `st.cache` now caches to memory instead of to disk.
+
+**What happens if I run Streamlit the old way?**
+
+If you run `$ python your_script.py` the script will execute from top to bottom, but won't produce a Streamlit app.
+
+**What are the limitations of the new architecture?**
+
+- To switch Streamlit apps, first you have to kill the Streamlit server with **Ctrl-c**. Then, you can use `streamlit run` to generate the next app.
+- Streamlit only works when used inside Python files, not interactively from the Python REPL.
+
+**What else do I need to know?**
+
+- The strings we print to the command line when **liveSave** is on have been cleaned up. You may need to adjust any RegEx that depends on those.
+- A number of config options have been renamed:
+
+  | Old config                 | New config            |
+  | -------------------------- | --------------------- |
+  | proxy.isRemote             | server.headless       |
+  | proxy.liveSave             | server.liveSave       |
+  | proxy.runOnSave            | server.runOnSave      |
+  | proxy.watchFileSystem      | server.runOnSave      |
+  | proxy.enableCORS           | server.enableCORS     |
+  | proxy.port                 | server.port           |
+  | browser.proxyAddress       | browser.serverAddress |
+  | browser.proxyPort          | browser.serverPort    |
+  | client.waitForProxySecs    | _n/a_                 |
+  | client.throttleSecs        | _n/a_                 |
+  | client.tryToOutliveProxy   | _n/a_                 |
+  | client.proxyAddress        | _n/a_                 |
+  | client.proxyPort           | _n/a_                 |
+  | proxy.autoCloseDelaySecs   | _n/a_                 |
+  | proxy.reportExpirationSecs | _n/a_                 |
+
+**What if something breaks?**
+
+If the new Streamlit isn't working, please let us know by Slack or email. You can downgrade at any time with these commands:
+
+```bash
+pip install --upgrade streamlit==0.37
+```
+
+```bash
+conda install streamlit=0.37
+```
+
+**What's next?**
+
+Thank you for staying with us on this journey! This version of Streamlit lays the foundation for interactive widgets, a new feature of Streamlit we're really excited to share with you in the next few months.
+
+## Version 0.36.0
+
+_Release date: May 03, 2019_
+
+**Highlights**
+
+- 🚣‍♀️ `st.progress()` now also accepts floats from 0.0–1.0
+- 🤯 Improved rendering of long headers in DataFrames
+- 🔐 Shared apps now default to HTTPS
+
+## Version 0.35.0
+
+_Release date: April 26, 2019_
+
+**Highlights**
+
+- 📷 Bokeh support! Check out docs for `st.bokeh_chart`
+- ⚡️ Improved the size and load time of saved apps
+- ⚾️ Implemented better error-catching throughout the codebase